Colon Cancer
(6/11/08)-If your parent or sibling has had colon cancer, the odds are about one-in-ten that you too will develop the disease. The odds are about 1-in-twenty if you do not have this type of family history for the disease. There were an estimated 153,000 cases of colon and rectal cancer diagnosed in the United States in 2007, according to the American Cancer Society, and about 50,000 people will die from it.
In a recent study of the disease conducted by researchers at the Dana-Farber Cancer Institute, the results of which were published in a recent edition of the American Medical Association it was determined that patients who had a family history of the disease, had a better chance of surviving than did patients with no family history of the disease.
The study followed 1,087 patients being treated for Stage 3 colon cancer, which means that the cancer had spread to nearby lymph nodes but not to other organs. Of those patients, 195 or about 18% had a parent or a sibling with the disease. Of those who had a least one close relative with the disease, 25% were less likely to die of the disease during the 5.6 years of patient follow-up than those with none.
The risk of dying was even lower for those with two or more relatives with the disease. Those patients had a 51% lower risk of cancer recurrence or death. Researchers have hot been able to determine why this is proving to be the case.
(3/15/08)- The American Cancer Society and other leading health groups are recommending two more tests for colon cancer detection or prevention that they had not previously endorsed.
One test is virtual colonoscopy, which uses a CT scan to look for abnormal growths and, unlike the standard colonoscopy, does not require inserting a camera-tipped tube rectally. The other test involves an examination of stool samples to find abnormal DNA associated with cancer, and requires an entire bowel movement to be packed in a kit and sent to a laboratory.
There are now 7 tests that are on the accepted list of options available to test for colon cancer. Colorectal cancer is the second leading cause of cancer death in the U.S., accounting for 49,960 deaths and with148,810 new cases expected in 2008.
The new guidelines organize the tests in two groups and specify the intervals to perform them.
The first group consists of tests that can detect cancer or prevent it by finding pre-cancerous growths. They include:
The second group detects cancer, rather than preventing it. Two of the tests look for blood in the stool, and the third is the stool DNA test. Blood in the stool does not necessarily indicate cancer, since an illness like hemorrhoids can cause blood to appear in the stool.
(1/4/08)- Aetna, the health-insurance company with over 16.6 million members sent a letter to all doctors in its plan that it no longer would cover the anesthetic drug Propofol when used during colonoscopy procedures, except in rare cases. The policy will go into effect as of April 1, 2008. The company therefore joins WellPoint Health and Humana in calling the drug "medically unnecessary" for the procedure. United HealthCare will however continue to coverage usage of the drug during colonoscopies.
The anesthetic eliminates a good deal of the discomfort in undergoing the procedure in which doctors explore the lower intestine to identify, and if necessary remove, developing polyps or tumors before they become dangerous.
Popofol was originally marketed as Diprivan, and is now relatively cheap because its patent has expired and a generic version is available. It is however a tricky drug since it acts rapidly and no rescue drug is available to counteract its effects if a patient begins to have trouble breathing. The FDA has recommended that trained specialists who are not otherwise involved in the procedure administer it.
In using an anesthesiologist the cost of the procedure can increase by anywhere from $300 to $1,000. Aetna asserted that its billing records showed that 77% if colonoscopy patients in the New York metropolitan area receive Propofol, compared with 10% or less in other regions.
(2/5/05)-For the first time, cancer has replaced heart disease as the number one killer of Americans younger than 85 years of age according to a statistical report that was issued from the American Cancer Society. In 2002, the most recent year for which this data is available, 476,009 Americans in that age category died from cancer, compared with 450,637 who died from heart disease.
According to Dr. Eric Feuer, chief of statistical research for the National Cancer Institute, people younger than 85 account for 98.4 percent of the population. Dr. Feuer was the head statistician for the project. The report found that one of the biggest reasons for the drop in deaths from both causes was that fewer people were smokers.
Between 1965 and 2000, the number of Americans who were smokers dropped from 42% to 22%. The report went on to state that one third of all cancers were related to smoking. Another one third of cancers are related to obesity, poor diet and lack of exercise. Incidentally these same factors contribute to heart disease also.
There is some good news in connection with the battle against cancer. Cancer deaths have declined about 1 percent each year since 1996. With that said, there will be estimated 1,372,910 new cancer cases discovered this year. Of that number, it is estimated that there will be 570,260 cancer deaths. The five-year survival rate has risen to 74 percent from the 50 percent mark of the 1970's.
Lung cancer is the number one killer among cancer victims, with it claiming about 163,500 victims this year. Prostate cancer will be diagnosed in about 232,000 men this year, and it will kill about 30,350 of them. Breast cancer will be diagnosed in about 211,200 women, and it will kill about 40,410 in 2005.
(2/20/04)-The FDA has approved Erbitux for sale in connection with the treatment for colon cancer. Even though it is supposed to be used only in cases involving terminal cancer for those who have not been helped by chemotherapy, doctors will have the legal right to prescribe it for other uses also. Erbitux targets a "growth factor" protein that plays a role in the uncontrollable spread of tumor cells. Even though Erbitux has not been shown to prolong life, trials have shown that it does shrink tumors for a few months.
Although the exact pricing for Erbitux has not been established, cancer experts have estimated that it will cost about $30,000 a year, which is roughly the same price that Genentech's Avastin is expected to cost. Eventually the drug may be used in combination with other cancer fighting drugs in the form of a "cocktail drug" similar to that used in connection with the fight against AIDS.
Genetech's cancer fighting drug Avistan is expected to gain approval from the FDA shortly in the fight against colon cancer. The results of the late-stage clinical trial for its drug Avastin were impressive. To the surprise of many it appears that the drug starves tumors of oxygen and nutrients and has prolonged the lives of patients with colorectal cancer. The results came as a surprise since previous trials to starve tumors of oxygen and nutrients had failed. Avastin had previously failed in clinical trials aimed at halting breast cancer. The process of starving a tumor of its oxygen and nutrients is known as angiogenesis inhibition.
According to Genetech, patients given Avastin along with conventional chemotherapy lived significantly longer that those who were given the chemotherapy alone. "This is to my knowledge the first major randomized study that validates the concept" behind Avastin and similar drugs, said Dr. Leonard Saltz of Memorial Sloan Kettering Hospital in New York. Thus once approved for sale by the FDA, it is expected that Avastin will be used in conjunction with chemotherapy in the battle against colon cancer. The drug did cause some adverse side effects such as high blood pressure.
In the trial of 800 colon cancer patients, those who received Avastin plus chemotherapy lived an average of 20.3 months, compared with 15.6 months for those on chemotherapy alone. About 45% of the patients who were on Avastin saw their tumors shrink by a least half, compared with 35% who only received the chemotherapy.
At the same ASCA meeting in Chicago wherein the data for Avastin was presented, Imclone announced that its colon cancer drug Erbitux also provided substantial benefits to the patients who were given the drug. Erbitux is a genetically engineered antibody that blocks a growth factor on the surface of many cancer cells. In conjunction with chemotherapy, it extended survival by 1.7 months. In the trial group of 329-patients the drug shrunk the tumors of 50% or more of the patients while those on Erbitux alone had only an 11% shrinkage rate.
There are now 5 targeted cancer therapies on the market, which is up from 3 just two months ago which have been approved by the FDA. Two other drugs, AstraZeneca PLC's Iressa and Millenium Pharmaceuticals Inc.'s Velcade received FDA approval in May.
In 2000, Medicare paid for 2,2211, 925 colonoscopies; by 2002 the figure had risen to 3,135,738. Most medical professionals feel that a colonoscopy is the most effective test for determining the presence of cancer in the colon. On the other hand there has been a sharp decrease in some of the other testing methodologies for determining the presence of colon cancer.
A sigmoidoscopy procedure, which looks only at the lower part of the colon, where most cancers occur, was used in 236,139 Medicare beneficiary's tests in 2002, down from 543,502 in 2000. In 2000 Medicare paid for 1,759,880 fecal occult blood tests, while in 2002 that number dropped to 1,609,39. The fecal test screens for blood in the stool, which can be a sign of polyps in the colon.
Heart disease was the leading cause of death in the U.S. last year, followed by cancer in the number two slot. Lung cancer will cause an estimated 157,000 deaths in the U.S. this year, followed by colon cancer (57,000), breast cancer (40,000) and prostate cancer (29,000). According to a report from the National Cancer Institute, the Centers for Disease Control and Prevention, the American Cancer Society and the North American Association of Central Cancer Registries, the death rate has declined for all four of these types of cancers since 1990.
Colon cancer is the 2nd leading cause of death from cancer in this country, exceeded only by lung cancer. It is the 3rd leading diagnosed life threatening cancer in this country exceeded only by lung and breast cancer. It is estimated that 147, 500 will be diagnosed with the disease this year, of whom death will claim 57,100. But colon cancer is the most curable of the major cancers when treated while it still is localized.
According to the latest statistics, 90% of patients whose cancers are discovered before they have spread are alive and well five-year later. The rate is 100% among those who have pre-cancerous polyps detected and removed. It can be detected early and cured because it arises slowly in benign growths called adenomatous polyps that are easily detected and removed. Only 5 in 2,000 of these polyps become cancerous, which is a transformation that occurs on average over a 10-year period of time.
Despite all of the above, fewer than 40% of Americans who should be tested undergo any screening tests for colon cancer. Everyone who is over 50 years of age is, by definition, at risk, along with younger people with hereditary or other conditions that increase their risk. Colonoscopy is the most accurate and most expensive screening exam. It should be repeated every 10 years (some medical professionals would use a 5-year period of time as the guideline) after attaining the age of 50.
Arie E. Kaufman, a professor and chairman of computer sciences at the State University of New York, at Stony Brook, and a team of four researchers at the school have won a patent for a new way to scan for colon polyps. The new method does away with the need to drink a gallon of cleansing liquid before taking the exam. No sedative needs to be taken to administer the test.
Patients who undergo the test receive a box of food to eat the day before the exam. The food consists of a mix of apples, crackers and soup. At the beginning of the exam, a half-inch-long tube is inserted at the opening of the rectum, and the colon is inflated with carbon dioxide so that there are no collapsed areas where polyps might be hidden.
CT scans are taken of the patient lying on his stomach and then on his back. This procedure is then followed by two more back and front scans taken while the patient holds his breath for as long as possible. This procedure takes no more than 15 minutes. The data gathered from this procedure is then entered into the computer. The computer will then separate images of the colon from the rest of the pictures from the CT scan.
The computer than uses the data to build a 3-D model of the colon. A doctor uses another computer to "navigate" through the 3-D model, and this procedure can be done in about 15 more minutes. The technology is licensed to Viatronix Inc., a company that makes medical imaging products. According to Professor Kaufman "three or four Army hospitals are doing very extensive clinical studies comparing virtual colonoscopy to the conventional method."
Researchers in two separate studies have shown that aspirin can reduce the risk of developing colon and rectal polyps, the precursors of almost all colon cancer. The studies involved high-risk patients and did not deal with the issue of whether or not aspirin was helpful for people who are at average risk in developing colon cancer. Although few polyps actually do turn into cancer, it is impossible to ascertain which ones of them will become cancerous, so therefore it is necessary to have them removed whenever they are found in the colon. Please also see our article on Aspirin as a Preventive against Cardiovascular Events and its possible beneficial and preventive effects.
Dr. Robert Sandler of the University of North Carolina led one of the studies, and Dr. John Baron of Dartmouth-Hitchcock Medical Center in Lebananon, N.H, directed the other study. The North Carolina study involved 635 patients who had colon or rectal cancer. Half took a regular, 325-milligram aspirin each day, and the others took a placebo. Of the group that was taking the aspirin, 17% had grown new polyps after 31 months, while 27% of the placebo group had developed polyps in the same time frame.
In the Dartmouth study 1,121 patients who had already had polyps which had been removed were randomly divided into one of three groups. One group was given a placebo, the other group was given a regular aspirin and the third group was given an 81-milligram aspirin. Three years later, 38% of the group taking the baby aspirin had new polyps, as opposed to 47% of the group taking the placebo and 45% of those taking the regular aspirin. On the down side is the fact that aspirin can inhibit blood clotting and also can irritate the stomach lining, leading to ulcers.
The FDA approved a new drug, Eloxatin, for last-ditch use by patients with colorectal cancer. The drug is manufactured by Sanofi-Synthelabo, and the FDA review was done on an expedited basis so that the approval was completed after only a seven-week period of time. Eloxatin is already in use in 55 countries, but it is not a miracle drug that can cure colorectal cancer. Colorectal cancer is the second greatest cause of cancer deaths in this country only surpassed by lung cancer. Last year it resulted in the deaths of over 56,000 people.
Eloxatin was approved for use in combination with 5-FU in patients who failed to respond to the combination of 5-FU and irintecan now used for initial cancer therapy. The trial of the drug involved 463 patients and was used in combination with and compared to 5-FU alone. In the trial the combination of the drugs shrank tumors by at least 30 % in 9 % of patients, while either 5-FU or Eloxatin alone shrank the tumors in virtually none of the patients. The combination of Eloxatin and 5-FU also kept tumors from starting to grow again for 4.6 months, or 2 months longer than for 5-FU alone.
According to a study done under the leadership of Dr. David A. Lieberman, chief of gastroenterology at the Portland Veterans Affairs Medical Center in Oregon, colonoscopy proved far superior to the fecal occult-blood test and the sigmoidoscopy test in detecting colon cancer. Even when used together the fecal occult-blood test and the sigmoidoscopy test missed almost one-quarter of the tumors and precancerous growths detected by colonoscopy.
Dr. Lieberman and colleagues at 13 Veterans Affairs medical centers studied 2,885 veterans from 50 to 75 years of age, who volunteered for the colonoscopy. Results from the entire colon were compared with what was seen in just the lower third of the colon, the equivalent of a sigmoidoscopy, and with testing of patients stool samples for traces of blood.The colonoscopy detected cancer in 24 patients and serious precancerous growths in 282 others. The fecal blood test was positive in only 24 % of those cases, the sigmoidoscopy identified 70 % of the tumors and growths, and the two together identified 76 % of them. Colonoscopy is considered the " gold standard" test for colon cancer since it is considered to be 95% accurate. For a family with no history of colon cancer it is recommended that the test be given every 10 years starting with the age of 60. For those with a family history of colon cancer it is recommended that it be given every 5 years starting with the age of 50.
Data from a long time study seems to indicate that even the
fecal occult blood screening test reduces the colon cancer death
rate by about 20%. The study group was led by Dr. Jack S. Mandel,
a vice president of Exponent, a Menlo Park, Cal., research
company, and his colleagues, most of whom are at the University
of Minnesota. Dr. Ernest Hawk, chief of the gastrointestinal
cancer group at the National Cancer Institute's division of
cancer prevention, said that the test does reduce the colon
cancer death rate.
The study was first begun in 1975, and when the first results
were published in 1993 it showed that the test resulted in up to
a 33% reduction in the colon cancer death rate. In the latest
published results of the study 415 cases of the cancer were found
among 15,532 people who were offered annual fecal blood tests:
435 cancer cases were found among 15,550 people offered the test
every 2 years: and 507 cases among the 15,363 cases of people who
did not have the test. According to Dr. Steven Wolf, a professor
of family medicine at Virginia Commonwealth University "But
early detection presumes the cancer already exists. This takes us
to a new level".
The screening fecal-occult blood test should be taken once every 12 months for those 50 and older. It is one of the free preventive screening tests recommended for Medicare beneficiaries. Normally it costs about $10-$25, while a sigmoidoscopy costs $150 to $300 and a colonoscopy costs from $1,000 to $1,500.
The Food and Drug Administration has approved Camptosar as a new first-line treatment for advanced colorectal cancer, saying that the drug prolongs patient's survival time. Camptosar had already been approved as a second-line treatment for the disease. The drug is used in conjunction with traditional radiation therapy (5-fluorouracil and leucovorin).
The drug, which is a topoisomerase I inhibitor, which attacks an enzyme essential for cancer-cell growth. Generically the drug is known as irinotecan. Pharmacia Corp. of Peapack, N.J, manufactures Camptosar. A 6-month treatment with the drug costs about $15,000. The FDA's approval was based on two clinical trials involving about 800 patients that compared Camptosar in combination with 5-FU/LV to 5-FU/LV used alone. In one of the studies the median survival time increased to 17.4 from 14.1 months, while in the other study the median survival time increased from 12.6 months to 14.8 months.
Please also see our article on Can COX-2 Inhibitors Prevent Colon Cancer and Treat Rheumatoid Arthritis at the Same Time?
Supreme Court Justice Ruth Bader Ginsburg had undergone chemotherapy and radiation treatment for her colon cancer. Her sigmoid colon was removed on September 11, 1999 for what had been classified as stage-2 cancer. About 75% of stage-2 colon cancer patients are cured. The treatments began in October, 1999 and ended in June of 2000. The classification system rates the cancers up to stage-4. The sigmoid colon makes up the lower third of the large intestine. It now turns out that the original diagnosis of diverticulitis may also have been correct. The operating surgeon, Dr. Lee Smith discovered a perforation in her upper bowel that was non-malignant. It has been estimated that most patients in Justice Ginsburg's condition need at least 4 to 6 weeks to recuperate from this type of surgery.
Justice Ginsburg who is 69 years of age had been taken ill while teaching this summer on the island of Crete. Her ailment was originally misdiagnosed as acute diverticulitis. This type of misdiagnosis happens fairly often because extensive testing is required to enable the medical professionals to distinguish between the two ailments. In diverticulitis, a disorder of the large intestine occurs when the pouches that form on the outside of the colon become infected. Another famous individual who has been in the limelight in connection with colon cancer is the former New York Yankee and New York Met baseball player Daryl Strawberry. Pathologists perform follow up testing to determine how far the cancer has spread in the tubular bowel system. They also perform tests on the lymph nodes to determine the extent of the spreading of the cancer.
According to statistics from the American Cancer Society colon and rectal cancer is the 3rd leading type of cancer discovered among women. It ranks 2nd behind lung cancer in terms of causing death for both women and men. Cancer of the colon and rectum caused about 65,000 deaths in 1999 or about 11 % of all cancer deaths in the U.S. If detected early colon and rectal cancer has a cure rate of over 90 %, which the best cure rates among all types of cancers if discovered early. It is estimated about 130,000 Americans will be diagnosed with colon cancer this year. In its early stages it begins in the inner lining of the colon or rectum, spreads to the surrounding tissue and lymph nodes, then moves to the liver or lungs.
The simplest and cheapest test for colon cancer is a digital rectal exam by the doctor combined with a fecal occult blood-screening test. The occult blood test helps detect the problem because colorectal cancers and precancerous polyps often bleed slightly, and thus will leave tiny traces of blood on the stool. The Hemoccult II test involves smearing feces on test cards from 3 consecutive bowel movements. The cards are then mailed to a lab for chemical analysis. For the 2 days prior to and for the 3 days of the testing you are advised to avoid certain foods and drugs. Colon cancers usually begin as harmless polyps that can be found and removed fairly easily.
There are 2 other fecal tests on the market EZ Detect and Colocare that have few dietary restrictions and do not require direct handling of feces. The exact accuracy of these tests has not been fully determined.
All other tests require a thorough cleansing of the bowel beforehand via enemas and laxatives. A sigmoidoscope allows the doctor to examine the bottom third of the colon but not the top two-thirds. A colonoscopy uses a lighted scope to examine the entire length of the colon. The doctor can remove suspicious lesions or polyps during the exam. In the double-contrast barium enema test an x-ray examination is performed after the colon is filled with barium and air.
The following symptoms should be checked out more thoroughly if they continually reappear:
The American Cancer Society recommends that women and men over 50 undergo any one of the following cancer testing exams:
High risk individuals should begin a stricter examination routine once they reach the age of 40.
For prostate cancer articles see the following:
Basic Information on Prostate
Cancer-Part I
Predicting Survival after
Prostate Surgery-Part II
Prostate Specific Antigen (PSA) - Part III
Prostatitis-Part IV
FOR AN INFORMATIVE AND PERSONAL ARTICLE ON PRACTICAL SUGGESTIONS WHEN SELECTING A NURSING HOME SEE OUR ARTICLE "Selecting a Nursing Home"
By Allan Rubin
Updated June 11, 2008
http://www.therubins.com
To e-mail: hrubin12@nyc.rr.com or rubin@brainlink.com