Objective response of malignant carcinoid to radiation therapy

In a retrospective review, we were able to identify records for 18 patients who were treated for malignant carcinoid in our Departments of Radiation Oncology from 1974-1985. At postmortem examination, one was found not to have malignant carcinoid. In 4 cases irradiation was administered postoperatively to patients whose subsequent courses did not permit assessment of objective response. Using standard criteria for objective response, an objective response rate of 54% was observed in the 13 cases whose records were adequate to make this assessment. Of the 7 responses, 3 were complete within the treated field as judged by clinical findings (2 patients) or postmortem examination (1 patient). Of the 6 nonresponders, 2 interrupted treatment prematurely, 2 were treated to a planned dose of only 2000 and 2500 cGy, and 2 were treated palliatively to limited ports which included only partial volumes of tumor. We conclude that radiation therapy is an effective treatment modality with a high rate of objective response in the management of those patients with malignant carcinoid tumors who require non-surgical, anti-neoplastic therapy.