LEVAMISOLE/5-FLUOROURACIL ADJUVANT THERAPY SHOULD BE GIVEN TO ALL

LEVAMISOLE/5-FLUOROURACIL ADJUVANT THERAPY SHOULD BE GIVEN TO ALL Stage III colon cancer patients after surgery, a National Institutes of Health consensus panel concluded in a draft report on adjuvant therapy for colon and rectal cancer released April 18. The 5-fluorouracil and levamisole adjuvent treatment was recommended for patients both in and outside of clinical trials. Patients with Stage II or III rectal cancer are also at high risk for recurrence and should receive adjuvant therapy with a combination of chemotherapy and radiotherapy, but only in clinical trials, the panel maintained. The 13-member consensus panel, chaired by Glenn Steele, MD/PhD, New England Deaconess Hospital, met at the NIH campus April 16-18 to discuss the merit of post-operative, adjuvant treatments for colon and rectal cancer. The National Cancer Institute released a clinical update in October 1989 notifying physicians that the combination of levamisole and 5-fluorouracil had been found to extend the post-surgery survival rates for patients with Duke's Stage C colon cancer by 49%. The update was based on a trial conducted by the North Central Cancer Treatment Group and the Mayo Clinic involving 408 patients. The consensus panel based its conclusions on that trial and a second trial, the 1,296 patient Intergroup study, which was conducted by three NCI cooperative groups. * FDA's Oncologic Drugs Advisory Committee recommended in February that the combination be approved as an adjuvant therapy ("The Pink Sheet" Feb. 5, T&G-3). Levamisole will be marketed by Johnson & Johnson's Janssen unit under the trade name Ergamisol. An NCI staffer reported at the conference that he expected Ergamisol to be on the market by June. The panel report states that "a dramatic effect of 5-FU and levamisole relative to surgery alone on disease-free survival and overall survival was demonstrated for Stage III patients. Therapy with 5-FU and levamisole reduced the risk of cancer recurrence by 41% and the overall death rate by 33%. Overall survival percentages at three-and-a-half years were estimated to be 71% v. 51% for the control group." Regarding rectal cancer, the panel reported that "the best current adjuvant therapy involves both postoperative treatment with both chemotherapy and radiotherapy." The panel, however, cautions against using the therapy outside of a clinical trial setting. "At the present time, the most effective combined modality regimen appears to be 5-FU plus methyl-CCNU, and high-dose pelvic irradiation (45 to 55 Gy) but chronic toxicity considerations of methl-CCNU mitigate against using this regimen outside ongoing clinical trials." Stage I colon and rectal cancer patients have a five-year survival rate of 80% to 90% with surgery alone, and "should not receive adjuvant treatment," the panel maintained. Future trials in rectal cancer "must define the relative merits of combination chemotherapy, including 5-FU/levamisole; 5-FU, methyl-CCNU, and vincristine; and also introduce newer combinations of promise including 5-FU/leucovorin and other biochemical techniques for 5-FU modulation," the panel notes.