Whole abdomen radiotherapy for patients with peritoneal dissemination of endometrial adenocarcinoma

Abstract

Purpose No standard, universally accepted therapy exists for patients with adenocarcinoma of the endometrium with peritoneal dissemination. We report mature outcomes of selected patients with this uncommon pattern of spread treated with whole abdomen radiotherapy (RT). Methods and materials A retrospective review was undertaken of all patients with a diagnosis of endometrial cancer referred to the Radiologic Associates of Sacramento Medical Group between January 1, 1988 and October 1, 1999. Eleven patients were identified who had surgically proven peritoneal dissemination (peritoneal seeding) treated with whole abdomen RT as the sole cytotoxic therapy after operative cytoreduction. Ten patients had International Federation of Obstetrics and Gynecology (1988) Stage IV disease at diagnosis, and one had peritoneal dissemination at the time of initial recurrence after hysterectomy for Stage I disease. RT was administered to the whole abdomen using 10-MV photons in fractions of 1.0 or 1.5 Gy. A cumulative dose of 30 Gy was given in all patients, with shielding used to reduce the dose to the liver and kidneys. Partial abdominal volumes (pelvis plus paraaortic nodes) received supplementary dose at 1.5–1.8 Gy/fraction to bring the cumulative dose within the limited volumes to 46.2–54 Gy. Results Four patients developed progressive cancer within 13 months of completion of whole abdomen RT. One additional patient died of hepatic venoocclusive disease (radiation hepatitis) 15 months after RT without evidence of cancer recurrence. Five patients were alive and clinically cancer free 55, 129, 131, 134, and 178 months after RT completion. One patient died of unrelated causes 79 months after treatment completion. Conclusion Abdominal RT, in doses compatible with the acute and late tolerance of normal tissues, can eradicate small deposits of disseminated, intraperitoneal endometrial cancer. Currently, our patient selection criteria include limited peritoneal dissemination at diagnosis permitting complete surgical clearance (<1 mm residual) of visible and palpable disease, Grade 1 or 2 histologic features, lack of demonstrable extraabdominal metastasis, and absence of major medical contraindications.