Oral administration of BCG as a local immunotherapy of gastrointestinal cancer.

Antitumor effect of oral bacille Calmette Guérin (BCG) administration was investigated by both animal experimentation and clinical trials. In animal experiments, orally administered BCG inhibited metastasis of syngeneic tumor from the initial site in caecum to mesenteric lymph nodes. Measurement of chemiluminescent intensity of adherent cells obtained from mesenteric lymph nodes of treated hosts revealed elevated activities of these cells. In the clinical trials it was found that marked histiocytosis occurred in mesenteric lymph nodes of stomach and colorectal cancer patients treated by the oral BCG. The 2-year survival rate of treated patients with stage IV stomach cancer (44.4%) was significantly higher than that of the untreated patients (6.3%). The results of the present study indicate that the oral BCG administration would be an effective local adjuvant therapy following radical surgery to treat patients with gastrointestinal cancer.