Immunotherapy: its possible application in the management of large-bowel cancer

A follow-up study on chemoimmunotherapy (5-fluorouracil and BCG) in advanced gastric cancer

Two hundred and seventeen patients with advanced gastric cancer were classified according to the resectability of the tumour into two groups: I, resectable (non-radical surgery), 99 patients, and II, non-resectable carcinoma, 118 patients. Within each group patients were randomly assigned to receive 5-fluorouracil (5-FU) + BCG, 5-FU, or no further treatment (surgery only). BCG was given by scarification. A 2-year follow-up is reported. The group of patients with resectable tumours and receiving chemoimmunotherapy had a statistically significant prolongation of survival compared with the 5-FU and surgery only groups. No differences in survival were observed between these treatment modalities in patients with non-resectable tumour. These observations indicate that chemoimmunotherapy may be of benefit for a selected group of patients with gastric cancer.

Immunotherapy with BCG administered by scarification: standardization of reactions and management of side effects

The method of administering BCG by scarification is described in detail. A system of classifying the intensity of local reactions is proposed to standardize administration. The experience of the M.D. Anderson Hospital involving over 2700 patients is reviewed. Administration of BCG by scarification has been accomplished with safety and has been well tolerated and accepted. The most commonly observed side effects are discussed as well as their management.

Treatment of liver cancer with regional intraarterial 5-FU infusion

The results of a retrospective three year study of forty-six patients with cancer of the liver treated with regional intraarterial infusion of 5-FU are reported. No primary mortality was noted. Oblective overall remission rate was 43 per cent. Overall median survival from onset of treatment was six months. The one year survival rate was 33 per cent and the two year survival rate 11 per cent. Patients with an objective response had a significantly prolonged survival as compared with nonresponders, especially in the colorectal group: sixteen months versus four months. Survival was not related to tumor size and involvement of the liver. During treatment 42 per cent of the patients developed extrahepatic metastases. Quality of life was improved in 63 per cent of the patients. The results indicate that infusion therapy induces reasonable response and palliation but is inadequate for the control of extrahepatic tumor growth.

Prolongation of postoperative disease-free interval and survival in human colorectal cancer by B.C.G. or B.C.G. plus 5-fluorouracil

83 patients with colorectal carcinoma of the Dukes' C class were randomised to receive postoperative adjuvant therapy with B.C.G. alone or in combination with oral doses of 5-fluorouracil (5-F.U.), and have been followed for up to thirty months. Results were compared with carefully selected historical controls who were treated by surgery alone. A statistically significant prolongation of both disease-free interval and overall survival was observed in 50 patients receiving the combination of B.C.G. and 5-F.U. (P=0.03, P=0.01 respectively) as well as in 33 patients receiving B.C.G. alone (P=0.03, P=0.05 respectively). The efficacy of B.C.G.+5-F.U. was independent of the number of tumour-involved lymph-nodes in the surgical specimen. In contrast, B.C.G. given alone appears to be highly effective among 10 patients with 6 or more positive lymph-nodes (P less than 0.04) and ineffective (as yet) among 23 patients with 5 or less positive lymph-nodes. These results suggest that adjuvant immunotherapy, with or without chemotherapy, can improve the prognosis of surgically treated patients with colorectal carcinoma of the Dukes' C class.

Adjuvant immunotherapy and chemoimmunotherapy in colorectal cancer of the Dukes' C classification. Preliminary clinical results

Fifty-eight patients with Dukes' C classification of carcinoma of the large bowel were placed on adjuvant immuno- or chemoimmunotherapy with Bacillus calmette guerin (BCG) or combination of 5-fluorouracil (5-FU) plus BCG following primary and definitive surgery, and were followed for up to 21 months. Of twenty-six patients receiving BCG alone by scarification, five have relapsed with 75% of freedom from disease estimated at 15.1 months compared with 10.1 months in a group of carefully selected historical controls who had surgery alone (p = 0.12). The survival of all patients receiving BCG alone has not reached the 75 percentile yet, and the difference from controls is currently estimated at the 18% level. The combination of 5-FU plus BCG (studied in 32 patients) may be superior to BCG alone at this time, in that it appears to more effectively protect against tumor recurrence (75 percentile not yet reached compared to control, (p = 0.08). The survival of patients on 5-FU plus BCG also appears to be improved (p = 0.09). No patients have expired compared to a 75 percentile survival of 16.6 months in the control. Serial determination of plasma CEA was crucial in the clinical follow-up of these patients. Frequent CEA detetminations have led to early detection of clinical relapse. In the elevation of CEA suggests tumor recurrence with a high degree of probability in patients with past history of cancer of the large bowel.

Tumour immunology and the gut

This review set out to answer several questions related to tumour immunology and the gut. It is evident that in patients with gastrointestinal cancer there is a general depression of the immune response and this seems to be correlated with the stage of the disease. Paradoxically a specific immune response against definable tumour antigens can be demonstrated, both cellular and humoral mechanisms being involved although the complexities of this paradox require further analysis. Immunotherapy has been employed in gastrointestinal tumours in a sporadic way. The results suggest that gastrointestinal neoplasms may respond at least as well as other tumours. A firm conclusion awaits the results of controlled trials in which the bulk of the tumour has been effectively dealt with by other means or where combined immunochemotherapy is being used.