Chemoimmunotherapy of metastatic large bowel cancer: nonspecific stimulation with BCG and levamisole

The administration of two chemoimmunotherapy programs to 103 consecutive patients with metastatic colorectal cancer resulted in improved survival for patients who achieved either objective tumor regressions or disease stabilization for more than 8 weeks. Objective tumor regression was observed in 47% of patients treated with the Ftorafur-methyl-CCNU-methotrexate-Bacillus Calmette-Guerin (FTOR-MeM-BCG) program and in 34% of patients treated with the 5-fluorouracil-methotrexate-Baker's antifol (FU-M-BAF) +/- Levamisole program. The combinated median duration of survival for patients who achieved objective tumor regression and disease stabilization with FTOR-MeM-BCG was 13 months compared with 6 months for patients who had progression of disease (p = 0.001). The corresponding values for patients treated with FU-M-BAF +/- levamisole were 11 months and seven months, respectively (p = 0.001). While the role of BCG immunotherapy in these results remains speculative, the administration of levamisole immunotherapy did not appear to have influenced results significantly. Patients who presented at diagnosis with Dukes A, B and C lesions, and therefore had longer disease-free intervals, responded more frequently to chemoimmunotherapy and survived longer than patients who presented at diagnosis with Dukes D lesions. Similarly, greater antitumor effect was observed in patients with lower pretreatment plasma CEA levels evaluation of these pretreatment characteristics may have insignificant implications for the design of future clinical trials.