Effect of surgery on BCNU chemotherapy in a rat brain tumor model.

In Fischer 344 rats, 9L tumors were implanted in the left cerebral hemisphere. Compared with control animals not operated on, rats treated with an LD10 dose of BCNU 1 hour before or 1 or 12 hours after surgery on Day 16 postimplant had an increased life span of over 200% (greater than a 6 log cell kill). Minimal effect on survival was found when BCNU was administered during surgery. On the other hand, BCNU administered 12 hours before or 24 or 72 hours after surgery did not show any additive effect of surgery on BCNU treatment. These results suggest that in a clinical setting, a bolus of BCNU administered to tumor patients within 12 hours of surgery might increase substantially the total tumor cell kill compared with surgical resection alone.