Thursday, September 13, 2007

Waging War on Lung Cancer

by Ellen BrownFive years ago, when Ken Giddes was vacationing with his wife in Vancouver, British Columbia, the 61-year-old resident of Atlanta began feeling short of breath. But since he was "running around quite a bit," Giddes chalked up his problem to being an overachieving tourist. When he returned home, though, his shortness of breath persisted. The cause--uncovered by an x-ray--was a collapsed lung.But it wasn't until he underwent surgery to repair his lung, that the cause of the collapse was clear: lung cancer had eaten a hole in the air sack of his lung. After surgeons removed his lung in an effort to contain the cancer, they checked Giddes for any traces of cancer every three months. Within a year there was more bad news: a CT scan revealed 13 spots on his remaining lung.Surgery revealed the cancer had spread throughout his remaining lung. Giddes recalled that he was given less than a 30 percent chance of living another two years. But he decided to battle the cancer "with all the energy, hope and positive attitude I could muster." After 30 weeks of chemotherapy, he was told his cancer was in remission.Today, he's glad he didn't give up because he's beaten the odds, surviving five years since his cancer was diagnosed. And as the head of the Caring Ambassador Program, sponsored by Republic Financial Corporation, he's helping other cancer survivors wage war on lung cancer, too.Survival and DetectionLung cancer is the leading cause of cancer deaths among both men and women, according to the American Cancer Society. Since 1987, more women have died each year of lung cancer than of breast cancer.Detecting lung cancer in its early stages is difficult in some cases because the disease spreads very quickly and symptoms often don't appear until the disease is advanced. Only about 15 percent of lung cancers are found before the cells have spread to lymph nodes or distant organs.Still, the survival rate for the disease has improved over the years. The one-year survival rate for patients is about 40 percent today compared with 32 percent in 1973. And five-year survival is up from 8 percent in the 1960s to 14 percent today. Improvement in survival rates can be attributed, at least partially, to diagnostics and new drugs that the Food and Drug Administration has approved.Lung cancer can be diagnosed by:a chest x-ray or CT scan to check for spots on the lungsa microscopic analysis of phlegm cellsa bronchoscopy, which involves passing a lighted tube through the tubes that carry air to the lungs to see if tumors or blockages exist.If suspicious tissue or spots are detected, a needle biopsy is typically performed, so that a sample of the tumor can be obtained to confirm the diagnosis of lung cancer.There also are two other diagnostic tools that may be used in place of a biopsy.The Xillix LIFE-Lung Fluorescence Endoscopy System is a medical device FDA approved in 1996 for detecting bronchial tissue abnormalities in patients with previous, current or suspected lung cancer. A tube inserted through a patient's mouth into the bronchi (tubes leading from the trachea to the lungs) delivers a blue laser light to the bronchial tissue. The image the laser reveals is projected onto a video monitor. While normal tissue appears green, abnormal tissue will appear reddish brown. Suspicious areas can then be biopsied. The system was approved for use in conjunction with conventional white light bronchoscopy. While the illumination provided by the white light helps doctors identify tissue that looks abnormal, the new blue laser system detects more tissue changes than can be seen with the white light alone.The approval of this device is significant, says Harry Sauberman, chief of the ear, nose and throat devices branch in FDA's Center for Devices and Radiological Health. It can spot moderate to severe dysplasia (irregular tissue), "some of which may turn out to be malignant and you'll have a case of lung cancer," he explains. Patients with dysplasia can then be closely monitored, and if cancer appears, it can be treated in its earliest stages.The second diagnostic tool is an imaging agent called Nofetumomab (verluma). Approved by FDA in 1996, it can determine the extent of disease in patients already diagnosed with small cell lung cancer through a biopsy but who have not yet been treated. Nofetumomab is a fragment of a monoclonal (synthetic) antibody that, when tagged with a radioisotope, can detect a protein found on the surface of most small cell lung cancers. The antibody collects in tumor sites and other areas of the body where protein is detected and, using special cameras, doctors can see the areas as "hotspots." This information helps physicians see how far the cancer has spread without exploratory surgery or other diagnostic tests and allows them to develop a more effective treatment plan.According to Patricia Keegan, M.D., deputy director for the division of clinical trials design and analysis in FDA's Center for Biologics Evaluation and Research, the major advantage of using the imaging agent is that it allows doctors to do a full body scan of a patient. "The disadvantage is that it isn't as sensitive in any one area as other scans," she says. "It's not as good as a CT scan for picking up every liver metastasis. And it isn't as good as an MRI or CT scan of the head to pick up brain metastasis. But if all you want is a quick and dirty answer about whether the cancer is widely disseminated or not, it's a relatively simple test to do."TreatmentAbout 75 percent of lung cancer cases are categorized as non-small cell lung cancer, and the other 25 percent are small cell lung cancer. Lung cancer can multiply quickly and form large tumors, which sometimes spread to lymph nodes and other organs.Once lung cancer is detected, a treatment plan is developed based on the patient's physical health, whether the lung cancer is small cell or non-small cell and how extensively the cancer has spread. (See "Stages of Lung Cancer.") Treatment may include surgery, chemotherapy, radiation, or a combination of two or more of these therapies.FDA recently approved three therapies to treat non-small cell lung cancer: Photofrin (porfimer sodium), Taxol (paclitaxel) in combination with the commonly used cancer drug cisplatin, and Gemzar (gemcitabine hydrochloride) in combination with cisplatin.Photofrin, a light-activated drug, was approved in January 1998 for patients with early stage, non-small cell lung cancer who cannot undergo surgery or radiotherapy due to other medical conditions. Administered intravenously, Photofrin accumulates in the tumor cells. A laser, directed toward the cancerous tissue, then activates the drug. A significant side effect is extreme photosensitivity, making it necessary for patients to stay out of the sun "almost completely for about a month," says Grant Williams, M.D., a medical team leader in the division of oncology drug products in FDA's Center for Drug Evaluation and Research.Williams admits that the number of patients with early stage lung cancer who will be helped by Photofrin will be quite limited. "We're talking about a very small number of patients compared to the number of lung cancer patients who have extensive cancers that can't be operated on," he says.Williams notes, however, that Photofrin may also be able to relieve symptoms in some patients with advanced non-small cell lung cancer. He explains that Photofrin has been demonstrated to be helpful in relieving breathing difficulties caused by tumors that are obstructing the flow of air through patients' bronchial tubes. Approval for this use was recommended by an FDA advisory committee in September 1998. Final FDA action is pending.Taxol (paclitaxel), already approved to treat other cancers, was approved last year for use in combination with cisplatin for the first-line treatment of non-small cell lung cancer in patients who are not candidates for surgery or radiation therapy.Gemzar (gemcitabine hydrochloride), another already approved cancer drug, received an additional approval in August for use in combination with cisplatin for the first-line treatment of patients with inoperable, locally advanced or metastatic non-small cell lung cancer.Although results of some studies have shown that new treatments may only give patients an additional month or two to live, "there are not a lot of effective treatments for advanced stage non-small cell lung cancer," says Isagani Chico, M.D., a medical officer in FDA's division of oncology drug products.Because small cell lung cancer has typically spread by the time it's detected, it generally cannot be cured by surgery. Treatment usually begins with a combination of two or more drugs to kill cancer cells throughout the body. Later, treatment with more drugs combined with radiation therapy or radiation alone, is often prescribed. Chemotherapy (drugs) and radiation therapy shrink tumors in most patients, and sometimes the disease goes into remission. But in many cases the cancer begins to grow again when it becomes resistant to treatment.The Road AheadThe future and course of lung cancer research seems to vary tremendously depending on who you talk to. Some experts believe prevention and early detection are the best bet. Others insist that improved treatments and gene therapy will be the answer. Paul Bunn Jr., M.D., believes that more research needs to be conducted to see if it's feasible to use x-rays to screen cigarette smokers and people exposed to asbestos, who are at highest risk of developing the disease. Bunn, the director of the University of Colorado Cancer Center and past chairman of FDA's Oncologic Drugs Advisory Committee, believes that the increased use of tobacco among teenagers and adults must be curtailed and that one of the best weapons against lung cancer is prevention.As for lung cancer patient Ron Norgord, he's banking on a drug that's intended to cut off the blood supply to tumors using molecular technology. The 63-year-old resident of Pasadena, Calif., who has been on a variety of chemotherapy and radiotherapy treatments since he was diagnosed about a year and a half ago, was accepted in September into a clinical trial of a drug that inhibits the growth of tumor blood vessels at UCLA's Cancer Center. "I'm quite encouraged by the results so far," Norgord says. "It's too early to see yet, but I see some positive things coming out of the treatment." One positive sign came after his first treatment, when his chances for fighting infections improved because his white blood cell count finally came up into the normal range.Researchers are currently studying a variety of drugs and drug combinations designed to extend patients' lives and improve their quality of life. They are also studying various aspects of the disease in the hope of someday developing more effective treatments. Here are just a few of the recent findings, studies and developments related to lung cancer:Researchers at the Dana-Farber Cancer Institute and the Brigham and Women's Hospital in Boston have identified six factors that place patients with early-stage lung cancer at risk for recurrence. These factors include: large tumor size, a specific tumor subtype of adenocarcinoma (a type of lung cancer), evidence that the cancer has entered the channels of the lymph system, and the presence of certain proteins commonly associated with cancers. Patients with two or more of these risk factors have an increased chance of their cancers recurring. This knowledge may help doctors decide which patients would benefit most from chemotherapy after surgery.The Radiation Therapy Oncology Group, a federally funded cancer clinical trials cooperative group, which carries out multi-disciplinary research nationwide, recently began a randomized clinical trial that will evaluate whether amifostine, a radio-protective agent, can effectively reduce some side effects in certain lung cancer patients treated with combined radiation therapy and chemotherapy. The trial, which will study patients with inoperable non-small cell lung cancer, is important because lung cancer patients who are treated with radiation and chemotherapy sometimes develop inflammation of the esophagus, making it difficult for them to swallow.At an American Association for Cancer research meeting in March, E. Premkumar Reddy, Ph.D., director of the Fels Institute for Cancer Research at Temple University School of Medicine in Philadelphia, reported that discovery of a new pathway for tumor growth may help researchers develop new types of diagnostic tests and anti-cancer agents. The new pathway, Src-Stat-3, is believed to play a critical role in the proliferation of cancer cells in the lung, breast, prostate, and ovary.Meanwhile, lung cancer survivor Ken Giddes, who is also a voting patient representative on FDA's Oncology Drug Advisory Committee, continues to spread a message of hope to people throughout the country. "I want people to know that the diagnosis of cancer is not an automatic death sentence and to inform people of the many options available to them," he says. "I also want people to know that just because they have lung cancer they shouldn't be written off or forgotten. People try to make you feel bad, especially if you smoked, like it's your own fault. But I see plenty of people who have lung cancer and haven't smoked. And even if they did smoke, they didn't plan to get lung cancer."Ellen Brown is a writer in Lakewood, Ohio.

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