The Midwest Surgical Association Clinical results of intraoperative radiation therapy for patients with locally recurrent and advanced tumors having colorectal involvement Christina P. Williams, M.D. a , Harry L. Reynolds, M.D. a, *, Conor P. Delaney, M.D., Ph.D. a , Brad Champagne, M.D. a , Vincent Obias, M.D. a , Yong-Geul Joh, M.D. a , Jim Merlino, M.D. b , Timothy J. Kinsella, M.D. c a Department of Surgery, Case Western Reserve University, University Hospitals, Case Medical Center, Cleveland, OH, USA b Department of Surgery, Case Western Reserve University School of Medicine, Metro Health Medical Center, Cleveland, OH, USA c Radiation Oncology Department, Case Western Reserve University, University Hospitals, Case Medical Center, Cleveland, OH, USA Manuscript received December 4, 2007; revised manuscript December 4, 2007 Abstract Background: Intraoperative radiation therapy (IORT) may be useful in the treatment of patients who have a locally advanced primary and recurrent abdominopelvic neoplasm with colorectal involvement. Methods: A retrospective review of colorectal cancer patients treated since 1999 with IORT using the Mobetron device. Results: Forty patients underwent colectomy or proctectomy with IORT. All patients had evidence of local extension to contiguous structures and based on preoperative staging were deemed by the operating surgeon as being likely to have incomplete resection. IORT was selected as an alternative to sacrectomy or exenteration for an expected close margin in 10 patients. Mean survival was 35  26 months, and 1 patient had local recurrence. Conclusions: The introduction of IORT has allowed a selective treatment approach to locally advanced primary and recurrent neoplasms, which traditionally would have been deemed unresectable. Using IORT, extended resections may be avoided in selected high-risk patients with low risk of local recurrence and minimal morbidity. © 2008 Elsevier Inc. All rights reserved. Keywords: Colorectal cancer; Radiation; Intraoperative; Recurrence; Sacrectomy Surgery remains the primary management modality for patients with early-stage colorectal cancer. Neoadjuvant chemotherapy and radiation have become the standard of care for patients with stages II and III rectal cancer. Patients who present with locally advanced primary or recurrent colon and rectal cancers, particularly those with adjacent organ, pelvic sidewall, or sacral involvement, present a significant management dilemma. Although surgery plays a pivotal role in the treatment of these patients, a multimodality team approach is necessary to optimize outcomes. Preoperative chemotherapy and radiation therapy is fre- quently appropriate in these patients in an attempt to min- imize tumor burden before what will often be a challenging pelvic dissection. Surgical decision making regarding the extent of resection presents another clinical dilemma. In the reoperated abdomen and pelvis, standard planes do not exist, and it can be impossible to differentiate clinically scarring, radiation change, and tumor. Frozen-section eval- uation of margins is difficult and often unhelpful, secondary to the large surface area, which must be evaluated. With expected microscopic or gross involvement, resection of the adjacent organs, the pelvic sidewall, or the sacrum is pref- erable but not always feasible. In the patient who is medi- cally unfit, or who has unresectable disease at a margin, several studies have shown that intraoperative radiation therapy (IORT) is a useful adjunct and may provide a satisfactory means of local control and potential cure with acceptable morbidity [1–7]. This article outlines a single institution’s experience with IORT using a mobile electron- beam radiation device (Mobetron) as an adjunct to surgical resection. * Corresponding author. Tel.: +1-216-844-5798; fax: +1-216-844-5957. E-mail address: harry.reynolds@uhhospitals.org The American Journal of Surgery 195 (2008) 405– 409 0002-9610/08/$ – see front matter © 2008 Elsevier Inc. All rights reserved. doi:10.1016/j.amjsurg.2007.12.002