Colon cancer drugs should not be stopped early

NEW YORK, May 12 (Reuters) Elderly patients who undergo removal of an advanced colon cancer should complete at least 5 months of fluorouracil-based chemotherapy, new research suggests. Stopping these drugs any earlier raises the risk of recurrence, and the results are no better than having no chemotherapy at all.

While colon cancer patients must undergo surgery for a cure, to reduce the risk that the disease will return, chemotherapy is often given.

Dr Alfred I. Neugut and colleagues, at Columbia University in New York, note that 6 months of fluorouracil-based chemotherapy is the standard of care for treating colon cancer that has invaded nearby lymph nodes.

However, previous studies suggest that about half of the patients 65 years of age or older do not receive chemotherapy. The researchers primary goal was to analsye outcomes according to length of treatment with chemotherapy.

The study, which is reported in the Journal of Clinical Oncology, involved 3,733 patients in the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) cancer registry whose records were linked with their Medicare claims filed between 1995 and 1999.

In this group, 613 patients received no more than 4 months of chemotherapy. Their death rates were similar to those of 2011 patients who received no chemotherapy.

However, chemotherapy for 5 to 7 months reduced the risk of death from colon cancer by about 50 per cent.

Neugut and his associates point out that earlier cessation of treatment did not necessarily cause the decreased survival. They suggest that patients may be at high risk because of the same factors that lead to their discontinuing treatment.

Meanwhile, west coast researchers identified physical frailty, treatment complications, and lack of social and psychological support as factors associated with an incomplete course of chemotherapy, according to their paper in the Journal of the National Cancer Institute.

Dr Sharon B Dobie, from the University of Washington in Seattle, and associates also evaluated data from the SEER registry from 1992 to 1996 linked to Medicare claims for patients age 66 or older with surgically removed colon cancer.

Included were 2,162 patients who received no chemotherapy, 569 who received a less than complete course, and 1,980 who received a complete course, defined as 5 months or more.

The strongest predictors of an incomplete course were rehospitalization during the time chemotherapy was being given, age younger than 75 years, female gender and widowed status.

Dobie and her associates recommend interventions to improve social and physical support during treatment, as well as studies of patient preferences to more fully understand factors involved in chemotherapy completion.

REUTERS SI RK0920