Intraoperative radiation therapy with the photon radiosurgery system in locally advanced and recurrent rectal cancer: retrospective review of the Cleveland clinic experience

Susan Guo,David W Dietz,F Christopher Deibel,Feza H Remzi,Matthew Kolar,Arul Mahadevan,Chandana A Reddy,Neil Woody,John H Suh

doi:10.1186/1748-717x-7-110

Abstract

BackgroundPatients with locally advanced or recurrent rectal cancer often require multimodality treatment. Intraoperative radiation therapy (IORT) is a focal approach which aims to improve local control.MethodsWe retrospectively reviewed 42 patients treated with IORT following definitive resection of a locally advanced or recurrent rectal cancer from 2000–2009. All patients were treated with the Intrabeam® Photon Radiosurgery System (PRS). A dose of 5 Gy was prescribed to a depth of 1 cm (surface dose range: 13.4-23.1, median: 14.4 Gy). Median survival times were calculated using Kaplan-Meier analysis.ResultsOf 42 patients, 32 had recurrent disease (76%) while 10 had locally advanced disease (24%). Eighteen patients (43%) had tumors fixed to the sidewall. Margins were positive in 19 patients (45%). Median follow-up after IORT was 22 months (range 0.2-101). Median survival time after IORT was 34 months. The 3-year overall survival rate was 49% (43% for recurrent and 65% for locally advanced patients). Local recurrence was evaluable in 34 patients, of whom 32% failed. The 1-year local recurrence rate was 16%. Distant metastasis was evaluable in 30 patients, of whom 60% failed. The 1-year distant metastasis rate was 32%. No intraoperative complications were attributed to IORT. Median duration of IORT was 35 minutes (range: 14–39). Median discharge time after surgery was 7 days (range: 2–59). Hydronephrosis after IORT occurred in 10 patients (24%), 7 of whom had documented concomitant disease recurrence.ConclusionsThe Intrabeam® PRS appears to be a safe technique for delivering IORT in rectal cancer patients. IORT with PRS marginally increased operative time, and did not appear to prolong hospitalization. Our rates of long-term toxicity, local recurrence, and survival rates compare favorably with published reports of IORT delivery with other methods.

Highlights

Treatment for locally advanced rectal cancer consists of multiple modalities including surgery, radiation, and chemotherapy
A majority of these patients have been previously treated with external beam radiation therapy (EBRT), which may preclude the delivery of additional pelvic radiation
Using a single institutional database of patients treated with Intraoperative radiation therapy (IORT) for rectal cancer, we retrospectively reviewed our experience with the photon radiosurgery system (PRS) in the delivery of IORT for locally advanced and recurrent rectal cancer patients

Summary

Introduction

Treatment for locally advanced rectal cancer consists of multiple modalities including surgery, radiation, and chemotherapy. Many locally advanced lesions can be rendered resectable with preoperative chemotherapy and radiation, and modern recurrence rates range from 6-10 % after neoadjuvant therapy [1,2,3,4]. Intraoperative radiation therapy (IORT) has been used as part of a multimodality approach in an attempt to improve local control in this patient population. A majority of these patients have been previously treated with external beam radiation therapy (EBRT), which may preclude the delivery of additional pelvic radiation. IORT has been used in an attempt to increase local control in these patients. Patients with locally advanced or recurrent rectal cancer often require multimodality treatment. Intraoperative radiation therapy (IORT) is a focal approach which aims to improve local control

Methods

Results

Conclusion