MEMORANDUM FOR: Science Writers and Editors on the Journal Press List

Adding Radiotherapy to Chemotherapy Does Not Improve Disease-Free or Overall Survival of Rectal Cancer Patients

February 24, 2000 (EMBARGOED FOR RELEASE 4 P.M. EST February 29)

Katherine Arnold, Deputy News Editor, Dan Eckstein, (301) 986-1891, ext. 112

Rectal cancer patients treated after surgery with both chemotherapy and radiotherapy had no better disease-free survival or overall survival than patients who received chemotherapy alone, but a decrease in local recurrence was seen with the combined therapies.

These findings, from a study conducted by the National Surgical Adjuvant Breast and Bowel Project (NSABP), are presented by Dr. Norman Wolmark, M.D., and colleagues, in the March 1 issue of the Journal of the National Cancer Institute.

In the United States, rectal cancer patients are commonly treated with both chemotherapy and radiotherapy after surgery. This practice evolved in the absence of data from clinical trials designed to determine whether the addition of radiotherapy results in improved disease-free survival and overall survival. The NSABP study addresses this issue.

In the study, patients with Dukes’ B or C carcinoma of the rectum were randomly assigned to receive either postoperative chemotherapy (348 patients) or chemotherapy and radiotherapy (346 patients). Patients entered this study from September 1987 through December 1992. Female patients received leucovorin-modulated 5-fluorouracil (5-FU plus LV) as their chemotherapy; male patients received either 5-FU plus LV or a combination of 5-FU, semustine, and vincristine (a combination called MOF). Chemotherapy was started between 21 and 42 days following surgery. Radiation therapy, if used, was started between 3 and 5 weeks following completion of the first cycle of chemotherapy. As of September 30, 1998, the average follow-up time for surviving patients has been 93 months.

Postoperative radiotherapy resulted in no beneficial effect on disease-free survival (P = .90) or overall survival (P = .89), regardless of which chemotherapy was used. Radiotherapy did reduce the incidence of cancer recurrence in the region of the original tumor from 13% to 8% at 5 years of follow-up. Men receiving the 5-FU plus LV had a statistically significant benefit in disease-free survival at 5 years compared with those who received MOF, but no statistically significant benefit was seen regarding 5-year overall survival.

The authors conclude that the study findings have potential relevance to the commonly accepted standard of care for rectal cancer. Whether the 5% absolute decrease in locoregional relapse is sufficient to justify use of radiotherapy is a decision that must be made by the treating physician, they say.

In an editorial, Daniel Haller, M.D., says that, for physicians trained in the United States, postoperative combined modality therapy has become the accepted standard for patients with rectal cancer who are at high risk for locoregional and distant recurrence. However, there is not universal agreement that such patients require both chemotherapy and radiation therapy after surgery. Haller said that the evidence presented by Wolmark et al. permits consideration of deletion of radiation therapy in clinical practice, particularly in patients considered to be at low risk for local recurrence or when the morbidity of postoperative radiation therapy is considered to be high. If radiation therapy reduces local recurrence, then perhaps its use should be limited to those patients with particularly high risk for this pattern of failure, he says.

Dr. Haller notes that wholesale elimination of postoperative radiation therapy may be premature. However, he adds that any uncertainties introduced by the NSABP trial should prompt the evolution of innovative clinical trials to establish optimal therapies for patients with curatively resected rectal cancer.

Contact: Lori Garvey, NSABP, (412) 330-4621; fax: (412) 330-4661. Editorial, Sue Montgomery, University of Pennsylvania Cancer Center, (215) 349-5657; fax: (215) 349-8312.

Note: This memo to reporters is from the Journal staff and is not an official release of the National Cancer Institute (NCI) or Oxford University Press (OUP) nor does it reflect NCI or OUP policy. In addition, unless otherwise stated, all articles and items published in the Journal reflect the individual views of the authors and not necessarily the official points of view held by NCI, any other component of the U.S. government, OUP, or the organizations with which the authors are affiliated. Neither NCI nor any other component of the U.S. government nor OUP assumes any responsibility for the completeness of the articles or other items or the accuracy of the conclusions reached therein.



             
Copyright © 2000 Oxford University Press (unless otherwise stated)
Oxford University Press Privacy Policy and Legal Statement