Regional radiotherapy (RT), hyperthermia (HT) and chemotherapy in primary inoperable or recurrent rectal carcinoma: feasibility and operability

Full text: Patients with primarily inoperable rectal carcinomas without distant metastases, and some with local recurrence, are surgically curable if tumor shrinkage after preoperative treatment is achieved. The effect of preoperative RT alone or combined with chemotherapy is not satisfactory in many patients. In a previous pilot study, excellent local control was achieved with radiotherapy, oxaliplatin, continuous 5FU, and weekly hyperthermia before surgery. However, acute toxicity, mainly diarrhoea, was a problem, and the continuous administration of 5FU via a central venous line was cumbersome in an outpatient setting. In the present study 5FU was replaced with oral capecitabine, all the radiotherapy was customized by conformal techniques, and the radiotherapy dose was moderately reduced. Patients were included from August -03. Based on clinical and MR evaluation, all were considered inoperable or with high risk of pelvic failure after surgery alone. 23 patients (M15, F8) have completed preoperative treatment. Their stage were T4 (8), T3 (9) and local pelvic recurrence, all without distant metastases. Mean age was 58 years (range 21 - 74). The treatment schedule was: RT (2 Gy x 23 to primary tumor, mesorectum and regional nodes with margins, attempting to minimize dose to the ileum, and 2 Gy x 4-5 boost to the tumor, average total tumor dose 54.3 Gy), weekly HT just after RT, weekly oxaliplatin (50 mg/m2 simultaneous with HT), and capecitabine (825 mg/m2) the evening and morning before each RT fraction. Hyperthermia was given with BSD 2000 (Sigma-60 or Sigma Eye applicator) and use of invasive thermometry with Bowman probes. Therapeutic time was 60 min. at tolerable output. Trimodality treatment with conformal RT, HT, oxaliplatin and capecitabine is tolerable. In the present setting, the toxicity is less pronounced than in the first pilot study, and the treatment is easier in an outpatient setting. (author)