Calculator can help estimate odds of survival from colorectal cancer.

Researchers at the Mayo Clinic have developed a calculator, available online, that can help doctors estimate an individual's risk for five year survival after diagnosis of colon or rectal cancer.

The calculator takes into account 4 factors that indicate outcomes for both survival and cancer-free survival: the number of lymph nodes that contain cancer, how far the tumor extends into the colon wall, the tumor grade, and the patient's age.

Data from seven trials of comparing chemotherapy after surgery to surgery alone for Stage II and III disease were pooled to develop the calculations.

Dr. Charles L. Loprinzi and his colleagues published the results of their analysis in The Journal of Clinical Oncology on April 5, 2004.

Read an article about the study on Medscape.

Read the study abstract in The Journal of Clinical Oncology.

Alcohol consumption may increase risk of colorectal cancer.

Pooling data from 8 studies including nearly 500,000 people, researchers found a moderate increase in the risk of colorectal cancer in those who drank more than 2-3 drinks daily (30 gms of alcohol). The risk increased with more daily alcohol use with those drinking more than 45 grams a day having one and a half times the risk of occasional or non-drinkers.

There was no difference in risk for men or women or for the location of the tumor -- proximal or distal colon or rectum. It also made no difference if the drink was beer, wine, or liquor.

The study authors caution that the results are based on a single determination of use and do not take into account younger drinking or lifetime consumption.

About 4% of women and 13% of men reported 2-3 daily drinks at the beginning of the studies. None of the participants had been diagnosed with colorectal cancer at the time alcohol consumption measurements were made. Over the 6 to 16 years of follow up, 4,687 people got colon or rectal cancer.

Read an article in Reuters Health on Medscape.

Read the abstract in The Annals of Internal Medicine.

United Kingdom doctors demonstrate value of CT scans and CEA testing after treatment for colorectal cancer.

People with resected colorectal cancer were randomly assigned to receive either bolus 5FU with leucovorin or continuous infusion 5FU. After treatment ended, they were seen regularly in clinic. CEA ( carcino-embryonic antigen) was measured at each visit and CT scans of thorax, abdomen, and pelvis were done 12 and 24 months after the beginning of therapy.

Of 530 study participants, 154 (29%) had a recurrence. Of those, 65 were detected by symptoms, 31 by raised CEA, 35 by CT scan, and 14 by both CT and CEA. Another 9 were found some other way.

Overall, those whose recurrence was discovered by CT scan had better survival than those whose symptoms led to diagnosis of relapse.

Thirty-three patients were able to have potentially curable liver metatases removed. Thirteen (13) of those cases were found by CT scan, 8 by CEA, and only 2 by symptoms.

David Cunningham, Ian Chau, Mark J. Allen published their results in Journal of Clinical Oncology, Vol 22, No 8 (April 15, 2004).

The authors concluded, " Surveillance CT and CEA are valuable components of postoperative follow-up in stage II and III colorectal cancer."

Read the abstract in The Journal of Clinical Oncology.

Virtual Colonoscopy Less Successful than Previously Reported

Previous studies compared virtual colonoscopy (VC) favorably with traditional procedures using an optical colonoscope (OC). These studies were limited to single, specialized centers. However, a new study done in hospital medical centers with less experience and fewer specialists was disappointing.

People referred for routine, clinically indicated colonoscopy were examined with both virtual and optical colonoscopies within a two hours. There were 615 individuals in the study and 9 centers.

Virtual colonoscopy found only 39% of small adenomas or polyps less than 6 mm in size. It uncovered 55% of larger, potentially cancerous, lesions greater than 10 mm. VC also missed 2 of 8 cancers.

Accuracy varied greatly from center to center, and didn't improve as centers gained additional experience. Radiologists were required to have done at least 10 previous virtual colonoscopies prior to beginning the study.

Peter Cotton MD and his associates reported their findings in the April 14, 2004 Journal of the American Medical Association.

Read a Reuters Health article on Medscape.

Read the study abstract in The Journal of the American Medical Association.

Read an article in The LA Times.(Requires free registration)

Recurrence of peritoneal carcinomatosis can be treated successfully in some cases.

About 80% of colorectal cancer patients with peritoneal metatases who undergo surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) will have a recurrence.

Surgeons in the Netherlands studied median times to recurrence and the effectiveness of additional treatment after recurrence in 106 such patients. Sixty-nine (69) had recurrence during the study period.

If surgeons were not able to remove all signs of tumor in the abdomen, recurrence occurred much sooner at 3.7 months. Those patients whose cancers were resected completely went for a median 11.1 months before their cancer recurred. The shorter the period between initial treatment and recurrence, the shorter was survival after a second treatment.

After successful initial treatment, an additional surgical removal of tumor resulted in an additional median survival of 10.3 months. If patients were treated with chemotherapy when their cancer recurred, median survival time was 8.5 months. Treatment with radiology meant additional survival of 11.3 months. Those who received no more therapy after recurrence lived a median 1.9 months.

The authors conclude that "Treatment of recurrence after cytoreduction and HIPEC is often feasible and seems worthwhile in selected patients. Selection should be based mainly on the completeness of initial cytoreduction and the interval between HIPEC and recurrence."

Vic J. Verwaal, MD and his colleagues published their study in The Annals of Surgical Oncology 11:375-379 (2004).

Read an abstract in The Annals of Surgical Oncology.

Laparoscopic surgery for colon cancer is safe and effective.

Surgeons who removed colon cancer via laparoscopic surgery found patients survived as long as patients who were treated with traditional open abdomen techniques. The surgery was safe, with no difference in surgical mortality.

Patients recovered faster, requiring less time in the hospital and having bowel function return sooner. They also had less overall pain.

Five-year survival for laparoscopic patients was 76.1%, compared to 72.9 percent for those in the traditional group. Although higher, the researchers said that this was not statistically significant. At the end of five-years was 75.3% for the laparoscopic group and 78.3 percent for conventional surgery.

Dr. Ka Lau Leung, from the Chinese University of Hong Kong and his colleagues randomly assigned 400 patients to receive either laparoscopic or conventional surgery. Their research was published in the April 10, 2004 issue of The Lancet.

Read the study abstract in The Lancet.

Read a Reuters article about the research.

Tumors with microsatellite instability have a poor response to 5-flourouracil (5FU) therapy.

Overall, adjuvant treatment with 5-flourouracil improves survival in Stage III colorectal cancer patients. However, it has not been clear whether microsatellite instability (MSI) affects how successful 5FU treatment will be.

Researchers from the University of California at San Diego reviewed records of more than 200 stage II and III colon cancer patients treated at the University of California and Veterans Administration hospitals in San Diego between 1992 and 1999. In addition, DNA was extracted from preserved tumors and studied for microsatellite instability.

Thirty-six patients had high levels of microsatellite instability (17.6%). The rest were classified as non-high for MSI.

Patients who did not receive adjuvant 5FU chemotherapy had a higher risk of death than those who did receive 5FU. This held true for those with non-MSI tumors, but not for those whose tumors exhibited high microsatellite instability. For MSI positive patients, there was no survival benefit to receiving chemotherapy.

The authors believe that tumors with high levels of MSI may not be sensitive to 5-fluorouracil.

John M. Carethers MD and his colleagues report their findings in the February 2004 issue of Gastroenterology.

A similar study at multiple centers in the United States and Canada identified 95 tumors with high MSI (16.7%) among 520 patients participating in randomized trials of adjuvant chemotherapy. The MSI positive patients had a better five-year survival rate, but survival was not improved if they received chemotherapy.

Chemotherapy did improve survival in those with microsatellite stable (MSS) tumors.

Steven Gallinger MD and his colleagues concluded in JAMA, "Fluorouracil-based adjuvant chemotherapy benefited patients with stage II or stage III colon cancer with microsatellite-stable tumors or tumors exhibiting low-frequency microsatellite instability but not those with tumors exhibiting high-frequency microsatellite instability."

Read the abstract of the San Diego study in Gastroenterology.

Read the abstract of the multi-center study in the July 17, 2003 issue of The New England Journal of Medicine.

Young women with colorectal cancer often have anemia and advanced disease.

Researchers reviewed all cases of colorectal cancer from 1982 through 1999 in two hospitals in New York City. Of more than 3,500 patients, 1.6% (61) were younger than 40. Thirty-two of these young patients were women.

Nearly all of the women had anemia (87.5%) and 68% were diagnosed at a late stage. Seventy-nine percent had left-sided tumors.

Men had more left-sided tumors (86%) and less anemia (69%). Fifity-five percent of men had their colorectal cancer discovered at a late stage.

The authors urge that doctors question women with anemia about gastrointestinal symptoms and rule out colorectal cancer as a possible diagnosis.

Olusola Olofinlade MD and colleagues from the Gastroenterology Section at St. Vincent's Hospital in New York report their findings in Southern Medical Journal: Volume 97(3) March 2004 pp 231-235

Read the abstract from Southern Medical Journal.

Can sedatives prevent the development of colon cancer?

Using mice, researchers at MD Anderson Cancer Center and the University of Texas have shown the the sedative drug Nembutal can inhibit colon cancer in these animals.

Eight out of ten mice who did not receive the sedative drug developed colon cancer, while only 4 of 10 mice given Nembutal developed the disease. Later, only 20% of cancers spread to the liver in treated mice compared to 80% of the control group.

Colon cancer cells have receptors for the neurotransmitter gamma-aminobutyric acid (GABA) on their surfaces. In the brain GABA stops messages sent by other neurotransmitters to nerve cells. Scientists theorize that GABA may have a similar action on chemical signals of colon cancer cells.

Nembutal may interfere with GABA receptors to reduce the initial development of colon cancer and its spread.

Premal Thaker, M.D., a clinical fellow at the University of Texas, reported his laboratory findings at the 2004 annual meeting of the American Association for Cancer Research.

While he believes this may provide a new direction for colon cancer therapy, he warns that additional studies are needed before testing can begin in humans.

Read the story on Ivanhoe Newswire.