The clinical and histopathological effect of combined preoperative radiation and intratumoral injections in rectal cancer

: Twenty-one Surgical patients with carcinoma of the rectum (Group 3) were treated with preoperative radiotherapy and intratumoral injections of Pepleomycin and BUdR (5-bromo-2'-deoxyuridine). On the other hand, 25 patients (Group 1) were treated by surgery alone and 7 patients (Group 2) were treated with preoperative radiotherapy alone. The difference in the background factors of the patients for three groups was not significant. The total dose of preoperative radiation was 42.6 Gy., e.i., 30.6 Gy. (1.8 Gy./fr. X 5/wk) delivered to the entire pelvis plus an additional 12 Gy./fr. X 4/wk) to the primary tumor. The reduction rates in tumor regression on roentgenogram for Groups 2 and 3 were 30.5% and 46.5%, respectively. The extent of cancer cell invasion in rectal wall of the surgical specimens was examined histopathologically. In the preoperative radiation group, especially in Group 3, it was indicated that the stage of the lesion had been reduced. The rates of patients with an "ew" of less than 2mm were 64.0% in Group 1, 28.6% in Group 2 and 14.3% in Group 3 (Group 1-3): p = 0.02). The incidence of positive lymph nodes was higher in Group 1 than in Groups 2 and 3. In a histopathological investigation of the patients in Group 3, the degenerative changes were heavier than in Group 2. Scattered mucocele transformation from the submucosal layer through to the adventitial tissue was noted in Group 3. This study suggests that the clinical and pathological effect of this combination therapy is able to increase the local control and survival rate.