Lung Cancer, Maintainance Therapy

Lung Cancer Background Research How You Can Help All About Lung Cancer Background cancertypelungLung cancer is the leading killer among all types of cancer in the United States. It is estimated that lung cancer accounts for about 14% of all new cancer cases in 2012, but will cause nearly 28% of all cancer deaths. Over the past three decades, little improvement has been achieved in extending the lives of lung cancer patients. In the late 1970's, about 37% of people survived one year or longer after initial diagnosis; three decades later, this number had only improved to 43%. But there is hope. NFCR funds numerous leading researchers who are committed to finding more effective strategies for preventing, diagnosing and treating lung cancer. Through their dedicated efforts to build risk prediction models, identify cancer genes in early-stage lung cancer, design cutting-edge devices for monitoring drug response, and seek new strategies to overcome tumor drug resistance, NFCR scientists are leading the battle against the deadliest cancer. Building risk prediction models for smoking-related lung cancer NFCR Fellow Waun Ki Hong, M.D., M.D. Anderson Cancer Center NFCR scientist Waun Ki Hong, M.D., a world-renowned cancer researcher from the M.D. Anderson Cancer Center, has long been studying the role of smoking in lung cancer development. His research in this area is near completion and has provided insights into why only a subgroup of smokers are prone to have their DNA damaged by smoking and consequently develop lung cancer. By building risk models to predict the development of smoking-related lung cancer, Dr. Hong hopes that those who are deemed to be at high risk could take proactive measures early on that might prevent or delay lung cancer development. Dr. Hong's team has also initiated clinical research on the natural Indian curry spice, curcumin, to determine its potential in lung cancer chemoprevention (using drugs to prevent cancer). Dr. Hong's initial results on this agent are promising and further research may confirm its usefulness in cancer chemoprevention. Tailoring new anti-cancer drugs to the right patients NFCR Project Director Alan C. Sartorelli, Ph.D., Yale University laromustine is a promising new anti-cancer drug for patients with small cell lung cancer (SCLC) and several other types of cancer. Earlier clinical tests of laromustine in leukemia patients showed that the drug only works well in 30% of those patients, and this may very well be the case for patients with lung cancer. In the era of personalized medicine, NFCR scientist Alan Sartorelli, Ph.D., the discoverer of laromustine, is working to ensure that the right patients are selected for this new drug. Dr. Sartorelli knows that laromustine has a unique molecular mechanism: only tumor cells with low levels of a protein called AGT are likely to respond to it. Dr. Sartorelli's team at Yale University School of Medicine will use a two-pronged research plan to determine tumor types that will respond to laromustine. First, in a wide variety of tumor samples and matched control tissues, his team will accurately measure the AGT protein using a reliable and simple AGT method developed in his laboratory. Then the scientists will analyze the AGT gene in the tumor samples to assess how often certain cancers "turn off" the gene, causing these tumor types to be exceptionally responsive to laromustine. Dr. Sartorelli's research will determine a set of the tumor types sensitive to the drug-and this will assist clinical investigators to select and treat patients with lung and other types of cancer with a high likelihood of responding well to laromustine. Detecting one cancer cell in a billion NFCR Project Director Daniel A. Haber, M.D., Ph.D., Massachusetts General Hospital Cancer Center Cancer cells in the blood are very rare - as few as 10 among eight billion normal blood cells. While the existence of these circulating tumor cells (CTCs) has been known for roughly 140 years, CTCs have eluded researchers because there has not been technology sensitive enough to efficiently capture them -- until now. NFCR scientist Daniel A. Haber, M.D., Ph.D., and colleagues at Massachusetts General Hospital Cancer Center have designed a new microchip-based device called the CTC-chip, which can trap and isolate even a minute number of CTCs from a spoonful of blood running through the business-card sized chip. There are three important potential benefits to this discovery. First, it may help physicians do a better job of monitoring how effective a patient's treatment is in real-time. An initial clinical trial showed that a lowering in the amount of CTCs in the blood correlated well with treatment effectiveness. Secondly, the use of the CTC-chip may help physicians make more timely treatment adjustments, and improve patient outcomes. A clinical trial involving patients with non-small cell lung cancer revealed that new genetic mutations can appear within 3 to 4 months following initial treatment, causing tumor resistance to the current therapy. Continuous tracking of such genetic changes in individual patients is essential for doctors to make timely treatment adjustments, but it would be almost unthinkable as a treatment modality if this had to be done through repeated, painful, and invasive tumor biopsy. The CTC-chip offers a very practical alternative through non-invasive blood testing. Finally, the latest research with the CTC-chip suggests it may potentially be used to screen CTCs in the blood stream to detect cancer at an earlier stage, long before it actually metastasizes to distant organs, opening a new door for cancer early detection and screening. Dr. Haber is currently optimizing the CTC-chip for large scale clinical application. His breakthrough technology may soon become a treatment option, dramatically changing the face of clinical care for patients. Determining which patients will respond to Taxol, one of the most widely used chemotherapy drugs in the world NFCR Fellow Susan Band Horwitz, Ph.D., Albert Einstein College of Medicine Taxol, a natural product from the yew tree, has been used to treat over a million cancer patients with lung, breast, and ovarian cancer. In fact, internationally known NFCR scientist, Susan Band Horwitz, Ph.D., at the Albert Einstein College of Medicine, discovered the molecular mechanism of Taxol-that it binds and inhibits tubulin, a protein crucial to cell growth. However, lung cancer cells alter the type of tubulin protein expressed and Taxol may inhibit these different proteins less effectively. Dr. Horwitz reasoned that various types of tubulin proteins expressed by cancer cells may cause the resistance to Taxol observed in many patients. To focus on this very important problem, she has recently developed new techniques that enable her team to isolate and identify the different types of tubulin expressed in lung cancer cells as compared to normal cells. Importantly, the scientists will be able to learn if different types of tubulin proteins have varying sensitivity to Taxol. Dr. Horwitz's research is of high impact as it may be possible, by analyzing the type of tubulin expressed in a patient's cancer cells, to determine if they will respond effectively to Taxol even before the onset of treatment. How You Can Help These NFCR-supported research projects hold great promise for improving the treatment and survival of lung cancer patients, or possibly preventing lung cancer in the first place. What our scientists need is research funding. NFCR is committed to providing at least $300,000 per year to these outstanding scientists in order to keep their very promising research moving forward. When you donate to NFCR, your gift will help our scientists take vital next steps in this promising research and bring us closer to a cure for lung cancer. The table below illustrates what your contribution can do to advance these important NFCR-supported research initiatives (actual expense for each purpose may vary). Click here to learn more. All About Lung Cancer Lung-Cancer-Stages Surgery for Lung Cancer Overview The role of surgery in the management of lung cancer consists of obtaining a biopsy to make a correct diagnosis, determining the correct stage of the cancer in order to ensure optimal treatment and treating the cancer by surgical removal in selected situations. The decision to treat lung cancer surgically depends on the type of lung cancer, as well as several prognostic factors. Surgery is a common form of treatment for non-small cell lung cancer (NSCLC), whereas, it is not as commonly used with small cell lung cancer (SCLC). Types of Surgical Procedures for Diagnosing Lung Cancer In order to accurately diagnose a lung cancer, a biopsy, or small piece of tissue, must be obtained and examined under a microscope. Because of the use of computed tomography (CT) screening, the detection of small abnormal areas in the lung that may or may not be cancer has become more common. There are several procedures that can be used to perform a biopsy. CT Guided Fine Needle Aspiration Biopsy: CT guided fine needle aspiration biopsy is the most common way to evaluate possible cancers. A CT scan takes a very detailed picture of a patient’s suspected cancer, allowing the insertion of a thin needle to remove a sample of the tissue. This gives doctors the most information without resorting to a more invasive surgery (thoracotomy) and direct biopsy. Thoracotomy: During a thoracotomy, a surgeon makes a large incision in a patient’s chest in order to directly access the mass and directly remove part or all of the suspicious area. In some patients with a peripheral lung mass and no evidence of mediastinal or systemic cancer, a wedge resection of the lesion is sometimes performed and diagnosis made on a frozen-section of tissue. If lung cancer is confirmed, a formal cancer resection is then performed. Endoscopic Ultrasound Guided Fine Needle Aspiration Biopsy: The mediastinum is the area behind the breast bone and consists of blood vessels, lymph nodes and other structures. Because lung cancer frequently spreads to lymph nodes in the mediastinum, biopsies to this area are often necessary. An endoscopic ultrasound guided fine needle aspiration biopsy is often used to evaluate the mediastinum. This technique is performed in order to avoid the more invasive procedures of mediastinoscopy or thoracotomy. Using this technique, more invasive methods of diagnosis can be avoided in approximately 50% of patients. An ultrasound machine is used to take pictures of the mediastinum, allowing a small biopsy needle to be directly inserted into the suspicious area without making an incision in the chest. Cervical Mediastinoscopy: Mediastinoscopy is another diagnostic procedure used to determine whether mediastinal lymph nodes contain cancer. This procedure is used in cases where endoscopic ultrasound guided fine needle aspiration biopsy is not indicated or was not successful. Medianstinoscopy requires general anesthesia, a small anterior neck incision and insertion of an endoscope, which is a thin, lighted tube. A complete procedure includes extensive sampling of lymph nodes in the upper and lower mediastinum. Bronchoscopy: During a bronchoscopy, a physician inserts a bronchoscope (thin, lighted tube) through the nose or mouth into the trachea (windpipe) and bronchi (air passages that lead to the lung). Through this tube, the surgeon can examine the inside of the trachea, bronchi and lung and collect cells or small tissue samples. Thorascopy: During this procedure, an endoscope called a thorascope is inserted through a small incision in the chest wall. Thorascopy is a limited surgical procedure that allows the lining of the chest wall and the lungs to be examined and biopsied to determine if cancer is present. Treatment Procedures Small cell lung cancer is not typically treated with surgery because the disease is usually widespread at the time of diagnosis. Once a diagnosis of SCLC is made and the amount of disease is characterized as either limited or extensive, patients typically receive treatment with chemotherapy and possibly radiotherapy. However, good results from surgery alone have been reported in a small subgroup of patients that have a small primary cancer and no lymph node involvement. Sometimes surgery is used in conjunction with chemotherapy and/or radiation therapy, but the contribution of surgery to overall outcome is not clear in this setting. Approximately 45% of all patients with NSCLC have cancer that is limited to the chest. For these patients, surgical resection is not only an important therapeutic modality, but in many cases, the most effective method of controlling the disease. Patients with stages I-II localized cancer without spread to lymph nodes are considered to have early stage lung cancer and are almost always treated with surgery. Patients with stage III cancer may be treated with either neoadjuvant chemotherapy followed by surgery or combined treatment with chemotherapy and radiation therapy. The following are the types of surgical procedures that may be performed in patients with stage I-III NSCLC. For patients with stage IV disease, surgery is usually not indicated. For more information about stage specific treatment strategies and results, refer to the treatment sections designed for each specific stage. Thoracotomy: Thoracotomy is a surgical procedure to open the chest and remove cancerous lung tissue. This surgical procedure is performed under general anesthesia. During a thoracotomy the surgeon may remove part or all of a lung. There are two operations to remove a small part of the lung. A wedge resection removes a very small part of the lung and segmentectomy removes a slightly larger part of lung based on anatomical segments. These types of operation are used when the cancer has been diagnosed early and is only in one very small area. A lobectomy is the removal of one lobe of the lung and is the most frequent operation performed for early stage NSCLC. A pneumonectomy is the removal of the entire lung. This procedure is performed when the cancer is found to involve more than one lobe. Pneumonectomy is associated with more than twice the mortality rate of lobectomy, as well as more long-term pulmonary side effects. Video-Assisted Thorascopic Surgery (VATS): This is a form of minimally invasive surgery that utilizes a television camera. The advantages of the camera-aided procedures are that smaller incisions can be used and there is no need to cut through a rib, which is necessary for conventional thoracotomy. This results in quicker, less intrusive surgery, with a much smaller scar. However, using these new procedures requires significant skill and a great deal of training. There is less, or at least different, visibility with VATS. If a serious problem arises, VATS can be converted to an open or traditional procedure, creating a small additional risk. Chest Tube Thoracostomy: This is a procedure performed to drain fluid, blood or air from the space around the lungs (pleural space). Copyright © 2012 Omni Health Media Lung Cancer Information Center. All Rights Reserved. Stage IIIB Non-Small Cell Lung Cancer Stage IIIB Non-Small Cell Lung Cancer OVERVIEW A stage IIIB non-small cell lung cancer (NSCLC) involves lymph nodes on the opposite side of the chest or above the collar bone, or is extensive (involves organs such as the heart or trachea) and also involves lymph nodes in the center of the chest (mediastinum) or near where the windpipe divides. A variety of factors ultimately influence a patient’s decision to receive treatment of cancer. The purpose of receiving cancer treatment may be to improve symptoms through local control of the cancer, increase a patient’s chance of cure, or prolong a patient’s survival. The potential benefits of receiving cancer treatment must be carefully balanced with the potential risks of receiving cancer treatment. The following is a general overview of the treatment of stage IIIB non-small cell lung cancer. Circumstances unique to your situation and prognostic factors of your cancer may ultimately influence how these general treatment principles are applied. The information on this Web site is intended to help educate you about your treatment options and to facilitate a mutual or shared decision-making process with your treating cancer physician. Most new treatments are developed in clinical trials. Clinical trials are studies that evaluate the effectiveness of new drugs or treatment strategies. The development of more effective cancer treatments requires that new and innovative therapies be evaluated with cancer patients. Participation in a clinical trial may offer access to better treatments and advance the existing knowledge about treatment of this cancer. Clinical trials are available for most stages of cancer. Patients who are interested in participating in a clinical trial should discuss the risks and benefits of clinical trials with their physician. To ensure that you are receiving the optimal treatment of your cancer, it is important to stay informed and follow the cancer news in order to learn about new treatments and the results of clinical trials. Optimal treatment of patients with stage IIIB lung cancer often requires more than one therapeutic approach. Thus, it may be important for patients to be treated at a medical center that can offer multi-modality treatment involving medical oncologists, radiation oncologists, surgeons and specialists in pulmonary medicine. COMBINED MODALITY TREATMENT Stage IIIB NSCLC often cannot be effectively removed with surgery. Historically, most patients with stage IIIB cancers were treated with radiation or with chemotherapy and less than 10% of patients survived 5 years with either treatment approach. Doctors have more recently learned that combining chemotherapy with radiation therapy may improve a patient’s survival. The results of a clinical trial comparing sequential chemotherapy and radiation therapy to radiation therapy alone was reported in the early 1990s and demonstrated that patients treated with the sequential approach were almost three times more likely to be alive 5 years from treatment when compared to patients treated with radiation alone. More recently, clinical studies suggest that the concurrent use of chemotherapy and radiation therapy also improves survival compared to radiation alone. These and other clinical trials have established combined modality therapy utilizing both chemotherapy and radiation therapy as a standard treatment approach for patients with stage IIIB cancers. CHEMOTHERAPY AS PRIMARY TREATMENT Patients with stage IIIB NSCLC who are unable or unwilling to receive radiation therapy can be treated with chemotherapy alone to alleviate the symptoms of their disease and prolong survival time. Over the past several years, chemotherapy has commonly consisted of a two-drug combination containing a platinum-containing compound (Platinol® or Paraplatin®), combined with a second chemotherapy agent. TARGETED THERAPY A targeted therapy is one that is designed to treat only the cancer cells and minimize damage to normal, healthy cells. Cancer treatments that “target” cancer cells may offer the advantage of reduced treatment-related side effects and improved outcomes. Avastin® (bevacizumab): Avastin is a type of targeted therapy that slows or stops the growth of blood vessels that deliver blood to the cancer, effectively starving the cancer of the oxygen and nutrients it requires to survive and grow. Avastin, in combination with the chemotherapy drugs paclitaxel and carboplatin, is FDA-approved for the treatment of advanced, non-squamous non-small cell lung cancer. Xalkori™ (crizotinib): Up to 7% of non-small cell lung cancers have an abnormal version of the ALK gene that contributes to the growth and development of cancer cells. Xalkori is an oral medication that blocks certain proteins, including the protein produced by this abnormal gene. For advanced non-small cell lung cancers that test positive for the ALK gene mutation, Xalkori has produced very promising rates of response.1 MAINTENANCE THERAPY Maintenance therapy refers to treatment that is given after initial treatment but before cancer progression. It is a relatively new approach to lung cancer treatment. Drugs that have been approved for maintenance therapy in selected patients include Alimta® (pemetrexed) and Tarceva® (erlotinib). For patients who are candidates for maintenance therapy, the approach has been shown to delay cancer progression and improve overall survival.2 3 TREATMENT OF ELDERLY PATIENTS Many NSCLC cases occur in people over the age of 70, but there is limited information about how best to treat older patients. As a result of the limited information and concern that elderly patients will not be able to tolerate aggressive treatment, older patients may be treated with single-agent chemotherapy rather than the combination chemotherapy that is commonly used in younger patients. Studies have suggested, however, that although combination chemotherapy increases side effects, it also improves survival among elderly patients.4 Because relatively few studies have focused on older lung cancer patients, additional research on this issue is warranted. STRATEGIES TO IMPROVE TREATMENT While some progress has been made in the treatment of stage IIIB NSCLC, the majority of patients still experience disease recurrence and better treatment strategies are needed. The progress that has been made in the treatment of NSCLC has resulted from improved pre-treatment staging of the cancer, development of multi-modality treatments and participation in clinical trials. Future progress in the treatment of NSCLC will result from continued participation in appropriate clinical trials. Currently, there are several areas of active exploration aimed at improving the treatment of stage IIIB NSCLC. New Approaches to Targeted Therapy: Researchers are continuing to evaluate new targeted therapies for the treatment of NSCLC. Tarceva, for example, which already plays a role in lung cancer maintenance therapy and second- and third-line lung cancer treatment, also appears to improve outcomes among newly diagnosed patients. Patient selection is important, however: studies in newly diagnosed patients suggest that the benefit of Tarceva is largely restricted to patients whose cancer has a mutation in the EGFR gene.5 Erbitux® (cetuximab) is another targeted therapy that has produced promising results in selected patients with NSCLC.6 Improved Approaches to Radiation Therapy: New radiation therapy technology is allowing physicians to more precisely target the cancer. This allows higher doses of radiation to be delivered to the cancer while reducing damage to normal tissue. For example, by using a special computer and CT scan, radiation therapy can be delivered more precisely to the cancer in the lungs. This technique is called 3-dimensional conformal radiation therapy. REFERENCES: 1 Kwak EL, Bang Y-J, Camidge DR et al. Anaplastic lymphoma kinase inhibition in non-small-cell lung cancer. New England Journal of Medicine. 2010;363:1693-1703. 2 Ciuleanu T, Brodowicz T, Zielinski C et al. Maintenance pemetrexed plus best supportive care versus placebo plus best supportive care for non-small-cell lung cancer: a randomised, double-blind, phase 3 study. Lancet. 2009;374:1432-40 3 Cappuzzo F, Ciuleanu T, Stelmakh L et al. Erlotinib as maintenance treatment in advanced non-small-cell lung cancer: a multicentre, randomised, placebo-controlled phase 3 study. Lancet Oncology. 2010;11:521-529. 4 Quoix E, Zalcman G, Oster J-P et al. Carboplatin and weekly paclitaxel doublet chemotherapy compared with monotherapy in elderly patients with advanced non-small-cell lung cancer: IFCT-0501 randomised, phase 3 trial. The Lancet. Early online publication August 9, 2011. 5 Zhou C, Wu Y-L, Chen G et al. Erlotinib versus chemotherapy as first-line treatment for patients with advanced EGFR mutation-positive non-small-cell lung cancer (OPTIMAL, CTONG-0802): A multicentre, open-label, randomized, phase 3 study. Lancet Oncology. Early online publication July 22, 2011. 6 Pirker R, Pereira JR, Szczesna A et al. Cetuximab plus chemotherapy in patients with advanced non-small-cell lung cancer (FLEX): an open-label randomised phase III trial. Lancet. 2009;373:1525-1531. Copyright © 2012 Omni Health Media Lung Cancer Information Center. All Rights Reserved. Small Cell Lung Cancer Overview Small cell lung cancers account for 20-25% of all lung cancers and are primarily diagnosed in smokers or former smokers. They differ from other types of lung cancer in that they spread very quickly throughout the body via the blood and lymphatic system. Accurate staging of small cell lung cancer is essential before definitive therapy can begin. A simple staging system is used to separate small cell lung cancer into 2 stages, referred to as limited and extensive. Limited and extensive disease are treated differently; therefore, your primary cancer doctor will perform a variety of tests to determine the stage of the disease and thus, the optimal treatment strategy. The tests will evaluate whether you have evidence of cancer in your bones, abdomen, brain and bone marrow. If these staging tests reveal no evidence of your cancer having spread outside a well-defined area in your lungs, then you will be diagnosed with limited stage small cell lung cancer. Otherwise, you will be diagnosed with extensive disease. However, it is important to understand that nearly all patients with small cell lung cancer already have cancer that has spread outside the chest, but cannot be detected with currently available diagnostic tests. Select from the following general stages of cancer in order to learn more about treatment options. Limited Small Cell Lung Cancer: Cancer is confined to a single side of the chest Extensive Small Cell Lung Cancer: The cancer cannot be well defined in the chest or has spread to other locations in the body. Recurrent/Relapsed: The lung cancer has been detected or returned (recurred/relapsed) following an initial treatment. Copyright © 2012 Omni Health Media Lung Cancer Information Center. All Rights Reserved. Non-Small Cell Lung Cancer Overview Accurate staging of non-small cell lung (NSCLC) cancer is essential before definitive therapy can begin. Staging is performed according to the tumor, node, metastasis (TNM) staging system. Select the following general stage of cancer in order to learn more about treatment. Stage I: The cancer measures 5 centimeters or smaller and does not involve the lymph nodes. Stage II: The cancer has not spread to the lymph nodes but is larger than 5 centimeters or involves structures near the lung such as the chest wall or diaphragm. NSCLC is also considered to be Stage II if it measures 7 centimeters or less and involves the lymph nodes within the lung or near the bronchus. Stage IIIA: The cancer involves lymph nodes in the space between the lungs (mediastinum) or near where the windpipe divides; is large or extensive but the only lymph node involvement is within the lung or near the bronchus; or there is no lymph node involvement but the cancer extends to other organs or tissues such as the heart, great vessels, trachea, or other lobes of the lung. Stage IIIB: The cancer involves lymph nodes on the opposite side of the chest or above the collar bone, or is extensive (involves organs such as the heart or trachea) and also involves lymph nodes in the center of the chest (mediastinum) or near where the windpipe divides. Stage IV: Cancer is found in both lungs, in the fluid that surrounds the lungs or heart, or has spread to other parts of the body such as the liver, brain, or bones. Recurrent/Relapsed: Cancer has progressed or returned (recurred/relapsed) following an initial treatment with surgery, radiation therapy and/or chemotherapy. Copyright © 2012 Omni Health Media Lung Cancer Information Center. All Rights Reserved. Lung Cancer Screening & Prevention Overview Information about the prevention of cancer and the science of screening appropriate individuals at high-risk of developing cancer is gaining interest. Physicians and individuals alike recognize that the best “treatment” of cancer is preventing its occurrence in the first place or detecting it early when it may be most treatable. Lung cancer is the most common cancer in the world and is the leading cause of cancer death, with 160,000 deaths in the U.S. annually. There are three main types of lung cancer. The most common are non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC), which together account for over 90% of all lung cancers. Malignant mesothelioma is a rare cancer that develops in the tissues that comprise the lining of the lung. The chance of an individual developing cancer depends on both genetic and non-genetic factors. A genetic factor is an inherited, unchangeable trait, while a non-genetic factor is a variable in a person’s environment, which can often be changed. Non-genetic factors may include diet, exercise, or exposure to other substances present in our surroundings. These non-genetic factors are often referred to as environmental factors. Some non-genetic factors play a role in facilitating the process of healthy cells turning cancerous (i.e. the correlation between smoking and lung cancer) while other cancers have no known environmental correlation but are known to have a genetic predisposition. A genetic predisposition means that a person may be at higher risk for a certain cancer if a family member has that type of cancer. Heredity or Genetic Factors While lung cancer has mainly been associated with environmental factors, there is emerging evidence that indicates that some individuals have a genetic predisposition for the disease. For example, individuals with chronic obstructive pulmonary disease appear to have an increased risk of developing lung cancer regardless of whether or not they smoke. Research is ongoing to further define the genetic factors associated with lung cancer. Environmental or Non-Genetic Factors Lung cancer is primarily associated with environmental factors, especially smoking. Several environmental agents have been associated with the development of lung cancer. Some are more easily avoidable than others. Cigarettes: There is a large body of research that indicates that individuals who smoke are at a significantly increased risk of developing lung cancer. Approximately 85% of the lung cancer cases diagnosed each year can be associated with smoking. Over time, carcinogens in cigarettes damage the cells in the lungs and eventually, these damaged cells may become cancerous. Several factors contribute to a smoker’s risk of developing lung cancer, such as the age at initiation of smoking, the number of years smoked, the depth of inhalation, and the number of cigarettes smoked daily. Cigars and Pipes: Individuals who smoke cigars or pipes appear to be at an increased risk of developing lung cancer, although this risk appears lower than that of cigarette smokers. Again, the number of years smoked, the amount smoked and the depth of inhalation all play a role in whether or not lung cancer will develop. Researchers have speculated that the reason for the decreased risk among cigar and pipe smokers when compared with cigarette smokers may be that cigar and pipe smokers do not inhale as deeply as cigarette smokers because cigar smoke tends to be more irritating. Cigar smokers also tend to smoke less each day, as it takes about 1-2 hours to completely smoke a cigar, whereas it takes less than 10 minutes to smoke a cigarette. Environmental Tobacco Smoke (ETS): Exposure to environmental tobacco smoke (also called secondhand smoke) is often referred to as involuntary or passive smoking. Prolonged exposure to ETS has been associated with an increased risk for developing lung cancer. Like smokers, nonsmokers who are exposed to ETS absorb nicotine and other carcinogens, however these carcinogens are less concentrated than if they were directly inhaled. Still, the carcinogens from ETS pose health risks for nonsmokers. Researchers have estimated that ETS is responsible for approximately 3,000 lung cancer deaths per year among nonsmokers in the U.S. In addition, children of smokers appear to have reduced lung function and more respiratory tract infections than children of nonsmokers. Lung Diseases: Some lung diseases, including tuberculosis (TB), have been associated with an increased risk of developing lung cancer. Lung diseases leave scarred tissue on the lungs that appear to increase susceptibility to lung cancer. Air Pollution: Although the relationship between lung cancer and air pollution has not been clearly defined, some research indicates that exposure to certain air pollutants may be associated with lung cancer. These air pollutants include by-products of fossil fuel combustion, exhaust from motor vehicles and diesel engines, and emissions from power plants and industrial centers. Asbestos: Asbestos is the general name applied to a group of naturally occurring minerals that form fibers. These asbestos fibers have been used in a variety of applications such as textiles, cement, paper, wicks, ropes, floor and roofing tiles, water pipes, wallboard, fireproof clothing, gaskets and brake linings. Asbestos fibers easily break into particles. When inhaled, these dust particles can lodge in the lungs and cause damage that leads to an increased risk of lung cancer. It is estimated that since the beginning of World War II, approximately 8 million people have been exposed to asbestos in the workplace. Approximately 5% of the lung cancer cases diagnosed each year are caused by asbestos. Clinical studies have demonstrated that individuals who are exposed to large amounts of asbestos have a 5 times greater risk of developing lung cancer than individuals who have not been exposed. In addition, individuals who smoke and are exposed to asbestos have an even greater risk. Studies show that smokers who are exposed to asbestos are 90 times more likely to develop lung cancer than individuals who do not smoke and have not been exposed to asbestos. Asbestos also increases the risk of developing mesothelioma, a rare type of lung cancer that develops in the lining of the lung. Mesothelioma can result from neighborhood or environmental exposure to asbestos, occupational exposure, and household contact with asbestos dust. The rates of mesothelioma peaked for individuals born around 1910 and have steadily declined over time. Currently, there are about 2,000 cases of mesothelioma each year. This is primarily an asbestos-related cancer; only a fraction of mesothelioma cases are unrelated to asbestos exposure. Individuals involved in shipbuilding during World War II have an increased risk of mesothelioma. In fact, several shipbuilding areas such as Virginia, England, Wales and Japan, have higher rates of mesothelioma. In addition, workers who are heavily exposed to asbestos bring the dust into their homes on their clothing, hair and skin, thus exposing their family members and placing them at a higher risk of developing mesothelioma. Smoking does not appear to increase the risk of developing mesothelioma. Radon: Radon is a carcinogen that can cause damage to the lungs that may eventually lead to lung cancer. It is estimated that radon is responsible for about 10% of the lung cancer cases diagnosed each year. Individuals who smoke and are exposed to radon are at an even higher increased risk of developing lung cancer. Most of the cancer deaths associated with radon occur among smokers. Radon is a naturally occurring, invisible radioactive gas. It is present in soil and rocks and can seep into homes and other buildings. In situations where ventilation is restricted, radon can accumulate in the atmosphere and lead to higher levels of exposure. Individuals who work in mines are often exposed to higher concentrations of radon than the general population. However, radon can also be present in many homes. Some geographic areas have higher concentrations of radon, but radon can also seep into homes in geographic areas that are not considered high risk. When ventilation is restricted in basements in order to conserve energy, radon can seep from the soil into the basement and accumulate in the poorly ventilated area. Prevention Cancer is largely a preventable illness. Two-thirds of cancer deaths in the U.S. can be linked to tobacco use, poor diet, obesity, and lack of exercise. All of these factors can be modified. Nevertheless, an awareness of the opportunity to prevent cancer through changes in lifestyle is still under-appreciated. Research is ongoing to determine the causes of lung cancer and find ways to prevent it. Avoiding the environmental risk factors may help to prevent lung cancer. In particular, refraining from smoking is an important factor in the prevention of lung cancer. Radon: The only way to determine if a home has elevated radon levels is to perform a test. Homeowners can purchase kits designed to test the radon levels in their homes. Geographic location is not a good indicator of radon levels. Homes that are located in the same area often have different indoor radon levels. Several factors contribute to increased radon levels including soil composition under and around the house and ventilation conditions. In addition, barometric pressure and precipitation can cause radon levels to vary over time. Because of the variances in radon levels, homeowners can utilize both short and long term tests to measure the radon levels in their homes. The tests are simple and inexpensive. Usually, a local or state radon official can assist homeowners in choosing the appropriate test. If elevated radon levels are detected in a home, the homeowner will need to take steps to reduce the radon levels. Once a radon problem is addressed and corrected, the risk is permanently eliminated. Asbestos: Nearly everyone has been exposed to asbestos at some point. Asbestos is widely used and small amounts may be found in a variety of products. In addition, the breakdown of asbestos products as well as natural deposits of the fiber can cause the release of asbestos particles into the environment. Three agencies are responsible for regulating the use of asbestos products and the exposure caused to the general public. The Environmental Protection Agency (EPA) regulates asbestos in buildings, drinking water and the environment. The Consumer Product Safety Commission (CPSC) regulates asbestos in consumer products. The Food and Drug Administration (FDA) monitors asbestos contamination in food, drugs and cosmetics. Still, individuals may be exposed to asbestos at work or in other environments. The Occupational Safety and Health Administration (OSHA) has issued regulations for employers regarding the treatment of asbestos exposure in the workplace. In addition, the Mine Safety and Health Administration (MSHA) regulates mine safety. Often, workers are provided with protective equipment and instructions regarding work practices and safety procedures. Individuals concerned about asbestos exposure at work may wish to discuss safety precautions with their employers or request information from OSHA.Individuals who are or have been exposed to asbestos should refrain from smoking. Diet: Diet is a fertile area for immediate individual and societal intervention to decrease the risk of developing certain cancers. Numerous studies have provided a wealth of often-contradictory information about the detrimental and protective factors of different foods. There is convincing evidence that excess body fat substantially increases the risk for many types of cancer. While much of the cancer-related nutrition information cautions against a high-fat diet, the real culprit may be an excess of calories. Studies indicate that there is little, if any, relationship between body fat and fat composition of the diet. These studies show that excessive caloric intake from both fats and carbohydrates lead to the same result of excess body fat. The ideal way to avoid excess body fat is to limit caloric intake and/or balance caloric intake with ample exercise. It is still important, however, to limit fat intake, as evidence still supports a relationship between cancer and polyunsaturated, saturated and animal fats. Specifically, studies show that high consumption of red meat and dairy products can increase the risk of certain cancers. One strategy for positive dietary change is to replace red meat with chicken, fish, nuts and legumes. High fruit and vegetable consumption has been associated with a reduced risk for developing at least 10 different cancers. This may be a result of potentially protective factors such as carotenoids, folic acid, vitamin C, flavonoids, phytoestrogens and isothiocyanates. These are often referred to as antioxidants. There is strong evidence that moderate to high alcohol consumption also increases the risk of certain cancers. One reason for this relationship may be that alcohol interferes with the availability of folic acid. Alcohol in combination with tobacco creates an even greater risk of certain types of cancer. Exercise: Higher levels of physical activity may reduce the incidence of some cancers. According to researchers at Harvard, if the entire population increased their level of physical activity by 30 minutes of brisk walking per day (or the equivalent energy expenditure in other activities), we would observe a 15% reduction in the incidence of colon cancer. Screening and Early Detection For many types of cancer, progress in the areas of cancer screening and treatment has offered promise for earlier detection and higher cure rates. The term screening refers to the regular use of certain examinations or tests in persons who do not have any symptoms of a cancer but are at high risk for that cancer. When individuals are at high risk for a type of cancer, this means that they have certain characteristics or exposures, called risk factors that make them more likely to develop that type of cancer than those who do not have these risk factors. The risk factors are different for different types of cancer. An awareness of these risk factors is important because 1) some risk factors can be changed (such as smoking or dietary intake), thus decreasing the risk for developing the associated cancer; and 2) persons who are at high risk for developing a cancer can often undergo regular screening measures that are recommended for that cancer type. Researchers continue to study which characteristics or exposures are associated with an increased risk for various cancers, allowing for the use of more effective prevention, early detection, and treatment strategies. No screening procedure for lung cancer has been proven to decrease the number of lung cancer deaths. For this reason, routine screening for lung cancer is not cost-effective. However, despite the fact that they do not reduce the number of lung cancer deaths, some screening procedures are effective at detecting lung cancer at earlier stages. Early detection of lung cancer leads to a better chance of a cure. Therefore, while screening for lung cancer is generally not considered cost-effective, individuals who smoke and/or are at a high risk of developing lung cancer may wish to undergo screening. There is currently no consensus as to the best way to screen for lung cancer. Historically, physicians have used imaging tests and sputum cytology to detect lung cancer. Although new screening procedures are being evaluated and refined, these methods are still widely used. Chest X-rays: Historically, chest x-rays have been used as a preliminary method to detect lung cancer. Japanese researchers have had some success improving lung cancer survival rates with the mass use of annual chest x-rays in high-risk populations. Some research indicates that chest x-rays combined with sputum cytology are effective in detecting early lung cancer. Although the tests appear effective in detecting lung cancer, there is not a large body of research that supports the routine use of these procedures, as they do not appear to reduce the lung cancer death rate. Computed Topography or CT Scan: A CT scan is a technique for imaging body tissues and organs, during which X-ray transmissions are converted to detailed images, using a computer to synthesize X-ray data. A CT scan is conducted with a large machine positioned outside the body that can rotate to capture detailed images of the oranges and tissues inside the body. This method is more sensitive and precise than the chest x-ray. Sputum Cytology: Sputum cytology is a procedure used to examine mucus that is coughed up from the lungs or breathing tubes. The mucus is examined under a microscope in order to detect cancer cells. Strategies to Improve Screening and Prevention Researchers continue to search for effective screening procedures for lung cancer. The potential for earlier detection and higher cure rates increases with the advent of more refined screening techniques. In an effort to provide more screening options and perhaps more effective prevention strategies, researchers continue to explore new techniques for the screening and early detection of cancer. Spiral CT Scan: A spiral CT scan is a new and better version of the old CT scan. During a spiral CT scan, the patient lies on a table that passes through the CT machine, which rotates around the patient. A computer then combines the images to create a 3D model of the lungs. This allows the physicians to view any potential areas of concern from infinite angles and to detect subtle changes in shape and contour. In recent studies, spiral CT scans have proven effective in detecting tumors as small as 1-2 millimeters. Research has shown that there is a decrease in cure rate for every millimeter increase in tumor size. Therefore, the use of spiral CT scans to focus on finding lung cancers below 1 centimeter holds promise for diagnosing early stage lung cancer. In addition, spiral CT scans can detect early emphysema. In a recent clinical study, the Early Lung Cancer Action Program (ELCAP) evaluated the benefits of using low-dose spiral CT scans. The results indicated that spiral CT scans could detect early lung cancer and early emphysema. One unexpected result of these early emphysema diagnoses was that many smokers in the study quit smoking after learning that they had emphysema. Thus far, low-dose spiral CT scans show potential for the early detection of lung cancer in high-risk people and offer the promise that more people could be cured. Further study will determine the validity of these results. In the meantime, individuals at a high risk of developing lung cancer may wish to undergo spiral CT scans despite the fact that this test is not yet routinely covered by insurance. Copyright © 2012 Omni Health Media Lung Cancer Information Center. All Rights Reserved.