Aim: Analysis of a pilot study including 29 consecutive patients with high surgical risk or refusal of colostomy treated with radiation therapy alone with curative intent.
Patients: Between 1986 and 1992, 29 patients were treated for infiltrating adenocarcinoma of the rectum. Median age was 72 years. Transrectal ultrasound staging was used in 24 patients (T1, 2; T2, 14; T3, 13; N0, 23; N1, 6). In 20 patients the lower border of the tumor was at 5 cm or less from the anal verge and in 19 patients the diameter exceeded 3 cm. CEA was elevated in seven cases.
Treatment: Contact X-ray (50 kV) was given first (70 Gy/3 fractions). External beam radiation therapy used a three-field technique in the prone position. Accelerated schedule (39 Gy/13 fractions/17 days) with a concomitant boost "field within the field' (4 Gy/4 fractions). Six weeks later an iridium-192 implant was performed in 21 (20 Gy/22 h).
Results: Median follow-up time was 46 months. Overall and specific survival at 5 years was 68% (SE = 0.09) and 76% (SE = 0.08). Local control was obtained in 21/29 patients (72%). There was one grade 2 rectal bleeding and five grade 2 rectal necroses. The overall tolerance was good in these frail patients.
Discussion: For T2. T3 or T1 > 3 cm diameter rectal adenocarcinoma, where contact X-ray alone is not recommended, a combined treatment with radiation therapy alone is able to give good local control with acceptable toxicity. This treatment should be restricted to inoperable patients.