Intraoperative and external beam radiotherapy in advanced resectable gastric cancer: technical description and preliminary results.

Twenty-two patients with resectable gastric cancer treated with intraoperative radiotherapy and external beam irradiation, in a Phase I-II oriented study, were analyzed. Tumor Stages were III & IV in 18 cases (82%). Tumor histology was described as diffuse undifferentiated type in 14 cases (63%). Following surgical resection of the primary tumor, IORT 15 Gy was delivered in the celiac axis area, using high energy electron beams ranging from 9 to 20 MeV. External beam irradiation fields covered the draining nodal areas of the upper abdomen and the gastric bed. There were no postoperative deaths. Reversible postoperative complications were recorded in 14 patients (63%). Long term complications observed were vertebral collapse and liver hemangiomas. First sites of recurrence have been: hepatic hilum (three cases), peritoneum combined with central axis nodes (two cases), liver metastasis (one case), and lung metastasis (one case). Survival data shows a follow-up period ranging from 1+ to 33+ months, with a median survival time for the entire group of 13+ months. At the time of this report, 16 patients (72%) are still alive and six have died (four from progressive malignant disease and two from intercurrent disease). From this preliminary data, it can be concluded that a combined approach with surgical resection, intraoperative radiotherapy, and external beam irradiation is feasible in advanced gastric carcinoma, and is not limited by toxicity or any complications observed. Despite this intense loco-regional therapeutic approach, the upper abdominal failure rate has been demonstrated in 22% of the cases.