Evaluation of a Simple Belly-Board Device for Reduction of Small Bowel Inside Rectal Cancer Radiotherapy Fields

Abstract

Background: We evaluated the efficacy of a simple belly-board device (BBD) designed and made in our department for reduction of small bowel inside the post-operative pelvic radiotherapy fields of rectal carcinomas.Methods: A very simple BBD was designed and manufactured in our department. It was made of acrylic glass, and was 128 cm long, 40 cm wide, and 9 cm high, with a 25x25 cm square opening, the lower border of which was set to be positioned about 3 cm above patients’ iliac crest. Patients to be treated post-operatively for rectal cancers were simulated using oral contrast with and without the BBD for postero-anterior (PA) and lateral fields. The small bowel surface area (SBSA) inside the fields was measured and compared in the films with and without the BBD.Results: Twenty-one patients, mean age 56 years, male-to-female ratio 2:1, 12 abdominoperineal (APR) and 9 low anterior resection (LAR), gave consent for this study. The mean SBSA were 7 and 13 cm2 in the lateral fields and 29 and 60 cm2 in the PA fields with and without the BBD, respectively (p = 0.001). The mean reduction in SBSA was 61% in the lateral fields, 53% in the PA fields, and 57% in both lateral and PA fields (p<0.001). The mean reduction in SBSA in lateral fields was 77% after LAR and 49% after APR (p=0.08). This difference was not significant for PA fields. The only factor with a significant effect was operation type (LAR versus APR) for reduction of SBSA in lateral fields (p=0.05). Gender, age, body mass index, and field sizes did not have a significant effect.Conclusion: The simple BBD could significantly reduce the SBSA inside the pelvic radiotherapy fields of rectal cancers. This reduction seems more pronounced after LAR in the lateral fields, compared to APR.