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| Sunday, April 22, 2007 |
| What Is Cancer? |
Cancer develops when cells in a part of the body begin to grow out of control. Although there are many kinds of cancer, they all start because of out-of-control growth of abnormal cells.
Normal body cells grow, divide, and die in an orderly fashion. During the early years of a person's life, normal cells divide more rapidly until the person becomes an adult. After that, cells in most parts of the body divide only to replace worn-out or dying cells and to repair injuries......
Because cancer cells continue to grow and divide, they are different from normal cells. Instead of dying, they outlive normal cells and continue to form new abnormal cells.
Cancer cells develop because of damage to DNA. This substance is in every cell and directs all activities. Most of the time when DNA becomes damaged the body is able to repair it. In cancer cells, the damaged DNA is not repaired. People can inherit damaged DNA, which accounts for inherited cancers. More often, though, a person's DNA becomes damaged by exposure to something in the environment, like smoking.
Cancer usually forms as a tumor. Some cancers, like leukemia, do not form tumors. Instead, these cancer cells involve the blood and blood-forming organs and circulate through other tissues where they grow.
Often, cancer cells travel to other parts of the body where they begin to grow and replace normal tissue. This process is called metastasis. Regardless of where a cancer may spread, however, it is always named for the place it began. For instance, breast cancer that spreads to the liver is still called breast cancer, not liver cancer.
Not all tumors are cancerous. Benign (noncancerous) tumors do not spread (metastasize) to other parts of the body and, with very rare exceptions, are not life threatening.
Different types of cancer can behave very differently. For example, lung cancer and breast cancer are very different diseases. They grow at different rates and respond to different treatments. That is why people with cancer need treatment that is aimed at their particular kind of cancer.
Cancer is the second leading cause of death in the United States. Half of all men and one third of all women in the United States will develop cancer during their lifetimes. Today, millions of people are living with cancer or have had cancer. The risk of developing most types of cancer can be reduced by changes in a person's lifestyle, for example, by quitting smoking and eating a better diet. The sooner a cancer is found and treatment begins, the better are the chances for living for many years.
Revised 02/06/2006
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posted by proletar @ 8:35 AM  |
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| Scientists Find One Reason Why Bladder Cancer Hits More Men |
Scientists have discovered one of the reasons why bladder cancer is so much more prevalent in men than women: A molecular receptor or protein that is much more active in men than women plays a role in the development of the disease. The finding could open the door to new types of treatment with the disease.
In an article in the April 4 issue of the Journal of the National Cancer Institute, Chawnshang Chang, Ph.D., of the University of Rochester Medical Center and colleagues show that the androgen receptor, which is central to the action of testosterone and other hormones that are much more plentiful in men than women, appears to play a key role in the disease.....
In experiments reported in the journal, mice without the receptor had dramatically lower rates of bladder cancer compared to normal mice with the receptor, and human cancer cells with the receptor were much more aggressive than those without it. Mice develop bladder cancer for many of the same reasons people do, and the molecular signals that control cancer development in mice mirror those in humans.
The disease hits about three times as many men as women, including estimates of 50,000 men and 17,000 women in the United States in 2007, according to the American Cancer Society. Some scientists have suspected that male hormones working in concert with the androgen receptor might play a role, but hard evidence has been minimal until now, said Edward Messing, M.D., a bladder cancer expert and chair of Urology. Instead, scientists have suspected that factors like greater exposure of men to cigarettes and industrial chemicals has been responsible.
“For many years, people have recognized that men are more likely than women to get bladder cancer,” said Messing, one of the authors of the paper. “More and more women are smoking and working with chemicals in the workplace, yet their bladder cancer rates have not really changed much. There is no longer any question that the androgen receptor is playing a role in bladder cancer.”
The work by a team of collaborators from Rochester and from Yokohama City University Graduate School of Medicine in Japan was led by Chang, director of the George Whipple Laboratory for Cancer Research at the University of Rochester Medical Center and a faculty member in the departments of Urology and Pathology and the James P. Wilmot Cancer Center.
Chang is an expert on the androgen receptor, which is central to many diseases and conditions, most notably prostate cancer. For that disease, hormone therapy to block the supply of hormones that turn on the receptor is a staple of treatment for men with advanced disease. The new findings open the possibility that perhaps someday, drugs that target male hormones, like those used against prostate cancer, might help men with bladder cancer.
The strongest evidence for the involvement of male hormones in bladder cancer was what happened when Chang’s team disabled the androgen receptor in mice. While their normal counterparts with the androgen receptor got significant levels of bladder cancer when exposed to a carcinogen – 92 percent of the males and 42 percent of the females – not a single mouse whose androgen receptor was knocked out developed bladder cancer. The mice without the receptor also had significantly fewer premalignant changes in their bladder.
Besides opening the door to possible new treatments, Chang says the findings could help doctors decide which cases of bladder cancer are most likely to re-occur. His team found a correlation between the frequency of the androgen receptor in tumor cells and the recurrence of the tumor – tumors more likely to re-appear had more of the protein. If the finding holds up in wider testing in human tumors, it would help doctors know which patients to treat aggressively right from the start.
The JNCI paper is the latest installment in a body of research Chang has compiled that shows that the story of the androgen receptor and male hormones like testosterone is much more complex than was once thought. For years it’s been widely thought by doctors and scientists that all male hormones, and only male hormones, work through the androgen receptor.
But he felt there was more to the story. If anyone would know, it would be Chang, who in 1988 was the first person to clone the androgen receptor, and was the first to discover that the protein needs molecular allies called co-factors to accomplish many of its tasks. Now more than 80 co-factors are known, offering many new targets to stop conditions like male-pattern baldness and diseases like prostate cancer.
Nearly a decade ago, Chang showed that molecules other than male hormones like testosterone are able to activate the androgen receptor. That finding isn’t simply gathering dust in textbooks; it likely explains why hormone therapy for men in the advanced stages of prostate cancer ultimately fails. His work explained a long-baffling phenomenon in these patients, where drugs that work well for a few years suddenly make the cancer grow again late in the course of the disease.
In the recent paper, Chang continued this line of work, only in bladder cancer instead of prostate cancer. He took a closer look at the nearly disease-free male mice that didn’t get bladder cancer despite exposure to a carcinogen. Some of those mice then received a drug known as DHT, a male hormone. In theory, such a drug only works if the androgen receptor is present, so the drug should not have had an effect. But 25 percent of these mice then got bladder cancer, clear evidence that the hormone is able to somehow side-step the traditional, receptor-mediated, pathway and still have an effect.
The work shows starkly that simply cutting off the supply of hormones like testosterone will have only a limited effect. The androgen receptor can still play a crucial role in the development of cancer, even without the hormones. The team has shown in other studies that even female hormones such as estrogen can turn on the androgen receptor.
“The activity of the androgen receptor is different from the activity of hormones that target the receptor,” said Chang. “We’ve shown very clearly that even without these hormones, the receptor is still active in the development of cancer. This is crucial information as doctors seek to develop treatments for diseases like prostate or bladder cancer in men.”
To knock out the androgen receptor, the team used a compound known as ASC-J9, a synthetic chemical compound that is loosely based on a compound found in curcumin. Chang’s laboratory, in collaboration with San Diego-based AndroScience Corp., has screened hundreds of compounds for their activity involving the androgen receptor. Just last month, the team showed that ASC-J9 offers promise against a rare neuromuscular disease known as Kennedy’s disease.
The compound is now being tested as a cream to treat acne in a clinical trial run by AndroScience, a biotech company founded by Chang, Charles C-Y Shih, and Por-Hsiung Lai in 2000. The University owns a stake in the company, which has licensed several of Chang’s research findings.
The first author of the paper is Hiroshi Miyamoto, M.D., Ph.D., who was a post-doctoral researcher in Chang’s laboratory and is now a medical resident in the Department of Pathology and Laboratory Medicine. Miyamoto was joined by several of his former colleagues at Yokohama City University Graduate School of Medicine in Yokohama, Japan, who did much of the work with the human bladder cancer cell lines and analyzed levels of the androgen receptors. Collaborators there include Hitoshi Ishiguro, Hiroji Uemura, Yoshinobu Kubota, and Yoji Nagashima.
Other authors of the paper, in addition to Chang and Messing, are Zhiming Yang, a former graduate student now at Zhejang University and 2nd Hospital in Hangzhou, China; Yei-Tsung Chen and Yueh-Chiang Hu, former graduate students and now researchers at Harvard; Yu-Jia Chang, formerly a post-doctoral researcher with Chang, now an assistant professor at Taipei Medical University and Hospital in Taipei, Taiwan; former graduate student Meng-Yin Tsai, now at Chang Gung Memorial Hospital in Kaohsiung, Taiwan; and Shuyuan Yeh, associate professor of Urology.
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| posted by proletar @ 8:29 AM |
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| Cancer Treatment Information |
Information about cancer treatment, including surgery, chemotherapy, radiation therapy, clinical trials, proton therapy, complementary medicine, and cutting edge technologies.
Biologic Therapy
The Basics learn about this exciting treatment which works by helping the immune system to function better by using substances that occur naturally in your body to fight cancer.
Bone Marrow Transplants
Support and information for bone marrow, peripheral blood stem cell, and cord blood transplant patients.
Chemotherapy
Information about chemotherapy treatment, drugs and side effects. Includes an overview of the treatment process and OncoLink Rx, a list of teaching sheets about chemotherapy drugs.
Clinical Trials
Tools to help empower cancer patients to evaluate research studies for which they may be eligible. Includes the OncoLink/EmergingMed Clinical Trials Matching Service, which encourages patients to seek out and consider clinical trials for the treatment of their cancer.
Complementary Medicine
A guide to help you navigate the realm of complementary and alternative medicine with tips and warnings on treatments such as herbals, vitamins, chemicals, diet, meditation, massage, acupuncture, and body-mind therapy.
Gene Therapy
Find out how researchers are trying to use this cutting edge therapy in an attempt to boost the immune system and improve the body's natural ability to fight cancer.
General Treatment Concerns
Tips from physicians on how to communicate with your cancer care team and make informed decisions about your care.
Hormone Therapy
Support and information about the various hormonal therapies used to treat many types of cancer.
PDT Center
Introductory information concerning photodynamic therapy (PDT) a novel cancer treatment which works by exposing a photosensitizing drug to specific wavelengths of light to kill cancer cells.
Proton Therapy
A down to earth explanation of this cutting edge treatment.
Radiation Oncology
Information about radiation therapy and treatment side effects. Includes an overview of the treatment process.
Surgical Oncology
Support and information about the various surgical procedures used to treat many types of cancer.
Targeted Therapies
A cutting edge technology that deals with drugs which target specific pathways in the growth and development of tumors.
Vaccine Therapies
One of the more complex topics in cancer treatment and one of the most rapidly changing fields of cancer research.
More Information
www.oncolin.com
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| posted by proletar @ 8:23 AM |
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| Online Cancer Decision Guide |
Today, you can make a life-changing decision-a conscious choice to step back from your current situation and determine what steps you need to take to give yourself the best chance to fight cancer and live a fuller, richer life. If you're determined to fight, we're determined to help you make the most important decision of your life. The Decision Guide gives you control over this decision process by helping you understand the key points in the decision-making process that you can influence. The future is in your hands.....
Our Oncology Information Specialists and physicians constantly look for a better way to help you learn what questions to ask when selecting a hospital and a physician. Use the Decision Guide to highlight the steps you need to take to make your treatment goals a reality. To simplify this process, we broke the Decision Guide into five basic steps:
Step One asks you to take a moment to help us better understand your situation. If you've registered for a Web Cast seminar, MyCancerCompass or any of CTCA's on-line programs in the past, your information will automatically populate the registration fields.
Step Two helps you review your treatment history, asks you to identify key decision-shapers who influence your decisions and points to any additional roadblocks you may encounter during your search for the best cancer care available.
Step Three asks you to develop a list of criteria you will use to assess treatment facilities and physicians.
Step Four is your opportunity to list the treatment facilities and the physicians upon which you wish to focus your search.
Step Five walks you through an analysis of both treatment facilities and physicians you plan to visit, and will provide you with an opportunity to review the facility where you currently receive care.
How Do I Use The Decision Guide?
There is no right or wrong way to use the Decision Guide, so it's helpful if you do not judge the answers to your questions this way! The Decision Guide simply asks you to begin organizing your thoughts and experiences dealing with cancer. We do this by presenting you with a series of questions designed to draw out some very honest responses.
As you work through the Decision Guide, you'll notice we left plenty of space for you to detail your responses to the questions. Your responses will be personal windows into all of the elements that shape the way you make decisions—your current treatment regimen, your emotions, your family members and your physicians play a central role in this decision. That's why it's important for you to understand how each of these areas weighs on the treatment decisions you make.
At the end of this exercise, you'll have the knowledge you need to measure your treatment facilities and physicians against a set of criteria you develop. You may not have the time or the energy to complete the Decision Guide in one sitting. Don't worry about it-we made this tool flexible to support your needs. If you're tired or you feel like you need to take a break, simply save your work and come back later when you're refreshed. Your answers will be waiting for you!
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| posted by proletar @ 8:19 AM |
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| Cancer: Medical Vocabulary |
The following are terms that you might hear during you or your loved one's diagnosis and treatment of cancer:
Adjuvant or neoadjuvant therapy: chemotherapy, radiotherapy or hormone therapy used to kill remaining cancer cells left behind after surgery.
Advance directive: instructions on what kind of care you would like to have if you become unable to make medical decisions.
Benign: any tumor, growth or cell abnormality that is not cancerous. The growth will not spread to deeper tissues or other parts of the body.
Biological therapy: therapy that uses the body's own immune system to attack cancer cells. Biological therapy is sometimes called immunotherapy, biotherapy or biological response therapy.
Biopsy: removal of a small portion of tissue to see whether it is cancerous.
Carcinoma in situ (CIS): cancer that involves only the cells in which it started and has not spread to deeper tissues or other parts of the body.
Chemotherapy: therapy that uses drugs to damage cancer cells and make it difficult for them to grow in number.
Clinical breast exam: examination done by a health-care professional who has training in breast health.
Clinical trials: research studies that involve actual patients. They are designed to find better ways to manage cancer from prevention and detection to diagnosis and treatment.
Colonoscopy: insertion of a long, flexible, lighted tube through the rectum and into the colon. This allows the physician to check the lining of the colon for abnormalities.
Colposcopy: procedure where a lighted, magnifying instrument (colposcope) is used to examine vaginal and cervical abnormalities.
Complementary and alternative medicine (CAM): therapy used during or after cancer treatment that may help relieve the symptoms of cancer and/or standard cancer treatments. Some examples of CAM include meditation, yoga, spiritual counseling, acupuncture and acupressure, and transcutaneous electrical nerve stimulation (TENS).
Digital rectal exam: exam where the doctor feels inside the rectum with his or her finger and checks for abnormalities.
Family history/genetic risk factor: increased risk of cancer because a close relative, like a mother or a sister, had or has had the disease.
Family physician: a doctor who specializes in treating every part and disorder of the human body. He or she may manage all or part of your cancer treatment.
Fecal occult blood test: test that checks for the presence of blood in the stool. This test can be used to help diagnose colorectal cancer.
Fibroid: a benign tumor usually found in the uterus.
Flexible sigmoidoscopy: insertion of a flexible, lighted tube into the rectum. This tube is shorter than the tube used in a colonoscopy. It allows the physician to check the rectum and part of the colon for abnormalities.
Follow-up: an appointment with your doctor after treatment to check the status of your cancer and overall health.
Invasive cancer: cancer that starts in one area of the body and then spreads to the deeper tissues of that same area.
Localized: cancer affecting only the cells of a certain area.
Lumpectomy: surgery that removes abnormal or cancerous tissue and sometimes part of the surrounding healthy tissue.
Malignant: indicates that cancer cells are present and may be able to spread to other parts of the body.
Mammogram: an x-ray taken of the breast in order to check for abnormalities.
Mastectomy: surgical procedure that removes all or part of a diseased (cancerous) breast.
Melanoma: a type of skin cancer where the cancerous cells are found in the melanocytes (cells that make the skin darker after being exposed to natural or artificial sunlight).
Nonmelanoma: a type of skin cancer where the cancerous cells are found in places other than the melanocytes.
Metastasis: the spread of cancer from one area of the body to another. For example, breast cancer may spread to the lymph nodes and lung cancer may spread to the brain.
Neoadjuvant therapy: chemotherapy given before surgery or radiotherapy.
Oncologist: a physician who specializes in cancer.
Palliative care: therapy that focuses on improving one's quality of life rather than curing his or her cancer.
Polyp: Usually a benign growth. Some polyps on the wall of the colon or rectum can contain cancer or become cancerous over time.
Pap smear: a test that involves the scraping and study of cells that line the cervix. Pap smears (also called pap tests) are used to detect precancerous and cancerous cells, as well as other noncancerous conditions.
Pathologist: a doctor who identifies diseases (such as cancer) by studying cells under a microscope.
Prognosis: the expected outcome of a disease and chances for recovery.
Prosthesis: an artificial replacement for a body part such as a breast or leg.
Prostate Specific Antigen (PSA) test: a test that measures the amount of a substance created by the prostate gland in the blood. An elevated amount could be the result of infection, prostate cancer or an enlarged prostate.
Radiation therapy (also called radiotherapy): therapy that uses high-energy rays (beams of light) or radioactive materials to damage cancer cells, making it more difficult for them to grow in number.
Reconstructive surgery: operation preformed to repair skin and muscles after surgery to treat cancer has been performed. Often used to reconstruct a breast after a mastectomy.
Recurrence: the development of cancerous cells in the same area or another area of the body after cancer treatment.
Risk factors: behaviors (such as smoking) or other circumstances (family or genetic history) that may increase your risk of cancer.
Side effects (of therapy): problems caused by the damage of healthy cells along with cancerous cells during treatment. Some common side effects of cancer therapy include being tired, feeling sick to your stomach (nausea), throwing up, hair loss and mouth sores.
Stages of cancer: the progression of cancer from mild to severe. Usually indicates whether it has spread to deeper tissues or other parts of the body. One method used by doctors to stage different types of cancer is the TNM classification system. In this system, doctors determine the presence and size of the tumor (T), how many (if any) lymph nodes are involved (N) and whether or not the cancer has metastasized (M). A number (usually 0-4) is assigned to each of the three categories to indicate its severity.
Surgery: a procedure that removes, repairs or allows for the further study of a specific body part.
Tumor: an abnormal mass of tissue that can be benign or malignant.
Source
American Academy of Family Physicians
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| posted by proletar @ 8:03 AM |
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