Abstracts
1997 Digestive Disease Week

Endocavitary radiation therapy as primary therapy for rectal cancer: a ten-year experience.

CO Finne III, KI Deen, D Johnson, WD Wong, RD Madoff. Division of Colon and Rectal Surgery, Department of Surgery, University of Minnesota Medical School, Minneapolis, MN.

Endocavitary radiation therapy (ECR) offers a non-operative treatment option for selected patients with rectal cancers. PATIENTS AND METHODS: 96 patients with carcinoma of the rectum were treated and followed prospectively from 1986 to 1996. 82 patients completed therapy, of whom 63 were treated with curative intent and form the basis for this analysis. There were 36 men and 27 women with a mean age of 68 years (37 to 104 years). Follow-up was available on all patients with a mean follow-up of 41 months (5 to 120 months). 35 patients received 9,000 cGy in three fractions, and 24 patients 12,000 cGy in four fractions. Four patients received 15,000 cGy or more. Endorectal ultrasound (ERUS) staging was performed in 52 patients; there were 28 uT1, 19 uT2, and 5 uT3 lesions. Seven lesions were greater than 3 cm in diameter. Mean distance from the anal verge was 8 cm (range 1 to 13 cm); 3 tumors were 3 cm or less from the anal verge. RESULTS: 16 of 63 (25%) tumors treated for cure recurred. Mean time to recurrence was 15 months. 13 of 16 patients underwent salvage operations, 9 for cure and 4 for palliation. 53 patients (84%) were disease free at follow-up or died of other causes; 3 patients (5%) are living with disease, and 7 patients (11%) are dead from cancer. Recurrence was seen in one uT1 patient (4%), seven uT2 patients (37%), and five uT3 patients (100%). Three of seven tumors (43%) larger than 3 cm recurred compared with 13 of 56 (23%) tumors 3 cm or smaller. All lesions within 3 cm of the anal verge recurred. CONCLUSIONS: ECR is an attractive treatment option for patients with early rectal cancer. High recurrence rates are seen in uT2 and uT3 lesions, lesions greater than 3 cm in diameter, and 3 cm or less from the anal verge, although salvage surgery with curative intent is possible in most cases. Preoperative ERUS optimizes patient selection for this therapy.