Surgical placement of biologic mesh spacers to displace bowel away from unresectable liver tumors followed by delivery of dose-intense radiation therapy

Purpose: Delivery of radiation therapy (RT) to unresectable liver tumors is sometimes limited by proximity of radiosensitive bowel. We sought to determine if biologic mesh spacers (BMS) could be used in this situation. Methods and materials: BMS composed of acellular human dermis were placed via a laparoscopic or open approach to displace bowel away from unresectable liver tumors in patients previously unable to receive radiation therapy (RT) due to risk of bowel toxicity. Results: In 1 year, 14 patients were treated. Median age was 64 years. Diagnoses included intrahepatic cholangiocarcinoma (n = 6), hepatocellular carcinoma (n = 3), and metastases (n = 5). A solitary lesion was present in 8 patients, while 4 patients had 2 lesions and 2 patients had 3 lesions. Median largest tumor size was 6.3 cm (range, 1.6-17.5 cm). Limited extrahepatic disease was present in 5 patients. The surgical approach was laparoscopic in 10 patients and open in 4 patients. Median length of stay was 2.5 days (1-8), and 3 patients developed low-grade complications. Folded, extra thick (2.3-3.3 mm) BMS, with a median area of 384 cm(2) (256-640 cm2), were used to displace stomach (n = 9), duodenum (7), colon (6), and small bowel (2). The mean displacement of these organs on postprocedure imaging was 23 mm, 23 mm, 24 mm, and 20 mm, respectively. Two patients did not receive RT due to extrahepatic disease progression. The remaining patients had 3-dimensional conformal proton RT (n = 5), stereotactic body RT (4), or intensity modulated RT (3). Median dose delivered was 54 Gy (40-58.5) in 5-15 fractions with only 1 patient with grade 3-4 toxicity. At short-term follow-up of at least 10 months, local disease control was obtained in 11 of 12 patients. Conclusions: Initial dual institution experience with this novel strategy demonstrates feasibility, allowing previously untreatable liver tumor patients to receive high-dose RT. (C) 2014 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.