Purpose: In a pilot-study patients with primarily non-resectable rectal cancer received a pre-operative radiochemotherapy to assess the tolerance and efficacy of this treatment protocol.
Patients and method: Twenty patients with non-resectable rectal cancer (Mason CS III-IV) have been irradiated from September 1989 through February 1994. The total dose, calculated at the isocenter, was 50.4 Gy with 5 fractions of 1.8 Gy per week with a small volume boost in selected cases. Chemotherapy was administered on 5 consecutive days in week 1 and 5 with 1000 mg/m2 5-FU per day as continuous infusion over 120 hours.
Results: The treatment was well tolerated. Acute toxicity included 1 grade III-dermatitis, 7 grade II-enteritis, 1 grade III- and 3 grade II-leucopenia. Seventeen out of 20 patients were resected 6 weeks after radiochemotherapy, 3 patients had no surgery (1 toxic death due to septicemia, 1 refusal of surgery after complete remission, 1 thrombocytopenia due to liver cirrhosis), all 3 had at least partial remission of their tumors. Fourteen out of 17 (82%) resections were curative (R0) with 1 additional R1- and 2 R2-resections. Ten out of 14 (71%) curative resected patients had no lymph node metastasis. A detailed histological examination showed regression in 15/16 tumors with fibrosis and vascular wall changes. Nine out of 16 patients had only minimal residual tumor.
Conclusions: In this pilot study, pre-operative radiochemotherapy was well tolerated. The relatively high rate of curative resections and marked histological tumor regressions of this approach requires further investigations in a randomized trial.