[The outcome of the postoperative radiotherapy of autonomic nerve preserving operation for lower rectal cancer].

PURPOSE

It is unclear whether adjuvant radiotherapy before or after surgery is effective for locally advanced, resectable lower rectal cancer. This study consists of a prospective randomized trial of postoperative radiotherapy for locally advanced curatively resected lower rectal carcinoma.

METHODS

We divided patients into two groups, one with postoperative 50 Gy radiation therapy to pelvic wall (N = 64), and the other with no radiation therapy (N = 46).

RESULTS

The 5 year disease-free rate was 61.8% in the radiation group and 70.6% in the no radiation group. There was statistically no significant difference between these two groups. The local recurrence rate was 2.7% (radiation therapy group: 1.6%, no radiation therapy group: 4.3%). This local recurrence rate was very low. These results made us suspect that postoperative radiation therapy was not always necessary to prevent local recurrence. Postoperative complications had a higher incidence in the radiation therapy group than in the no-radiation therapy group. In the radiation therapy group, 35.5% of the patients suffered from diarrhea or frequent defecation, and 10.8% from severe abdominal pain. We operated on 4 cases of radiation-induced ileal stenosis and ileus.

CONCLUSION

Postoperative radiation therapy did not help prevent local recurrence even though many complications resulted.