Salvage whole abdomen radiation therapy: its role in ovarian cancer

In spite of high initial response rates, many patients with epithelial ovarian carcinoma eventually fail their primary treatment. Further treatment with second-line regimens has been ineffective in producing durable responses. Thus, whole abdomen radiation therapy was evaluated as a salvage therapeutic modality as to its feasibility, efficacy, and toxicity.

Between June 1983 and June 1990, 44 patients who failed one or more chemotherapeutic regimens were treated with whole abdomen radiation therapy. Forty patients had epithelial carcinoma of the ovary and the remaining had primary adenocarcinoma of the peritoneal cavity. Radiation was delivered with an open-field technique and 2500 cGy were planned to the whole abdomen, with a boost when indicated. Prior to radiation, the amount of residual disease after debulking was noted to be microscopic in one-half of the patients and macroscopic in the other half. Pelvis alone was the site of residual disease in 14 patients, and upper abdominal involvement was found in 30.

Five patients (11%) were unable to complete the planned therapy secondary to acute toxicity. The 4-year actuarial survival and recurrence-free survival rates for the entire group were 23% and 22%, respectively. The survival and recurrence-free survival rates for the group with microscopic residual disease at 37% and 42% were significantly better than those for the patients with macroscopic residual disease at 9% and 5% (p < 0.005; p < 0.001) at 4 years, respectively. Patients with disease limited to pelvis only had a recurrence-free survival of 56% compared to 0% when the upper abdomen was involved (p < 0.005). The abdomino-pelvic cavity was the first site of recurrence in 28 of 31 patients in whom the site of recurrence could be determined. Eight patients (18%) experienced bowel complications, of whom five needed surgical intervention.

Whole abdomen radiation therapy with a pelvic boost is feasible with acceptable acute and late toxicity. It is effective in patients with minimal residual disease.