[Local recurrence of rectal cancers. Multidimensional analysis by anatomoclinical factors and role of irradiation].

Pre- or postoperative radiation therapy reduces the incidence of local recurrence after surgical treatment of rectal carcinoma. Factors related to local recurrence were analyzed retrospectively by uni- and multivariate analysis. One hundred and fifty-five patients (mean age: 65 years) were operated on with curative intent between 1967 and 1984. Ninety-four patients (46 patients having abdominoperineal resections (APR), and 48 having anterior resections) did not receive radiation therapy. Sixty-one patients had preoperative radiation therapy followed by APR in 59 cases. Univariate analysis showed that the risk of local recurrence increased significantly with male sex (p less than 0.006), positive lymph nodes (p less than 0.01), vascular invasion (p less than 0.02), and Astler-Coller classification (p less than 0.05). Tumor located at less than 5 cm from the anal verge was significantly related to recurrence only in patients not receiving radiation therapy (p less than 0.02). Multivariate analysis including therapeutic modalities showed that local recurrence was significantly related with male sex (p less than 0.02), positive lymph nodes (p less than 0.01), and distance to anal verge (p less than 0.01). The beneficial role of radiation therapy appeared only for tumors located 5 cm or less from the anal verge. Prognostic scores were established using these variables and the effect of irradiation was evaluated according to these scores. Radiation therapy significatively reduced the risk of local recurrence in low-risk patients, i.e., female with low-lying tumor and with negative lymph nodes (p less than 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)