Comparative Study to Evaluate Irradiated Small Bowel Volume with or Without Using Belly Board During Treating Pelvic Malignancy in 3dcrt Technique

Gastrointestinal (GI) toxicity is the most frequently encountered complication of pelvic radiotherapy with clinically significant acute and late toxicity occurring in up to 60% and 20% of patients, respectively. The current study was conducted to assess and compare irradiated small bowel volume and dose between prone position using belly board and supine position without belly board in pelvic radiotherapy. Methods: It was a quasi-experimental study conducted at the department of Radiation Oncology of NICRH. Sixty patients of rectal and cervical malignancy were included in the study. They were enrolled in either arm A or arm B to receive radiotherapy to pelvis in supine position or prone position with belly board, respectively by 3DCRT technique. Results: There were no statistically significant differences in distributions of the patients across the two arms regarding age and other various demographic data, abdominal girth etc. Irradiated volume was significantly low in arm-B (5189cm3 vs. 3485cm3, <i>p-value</i><0.001). Small bowel volume which received 45Gy was also significantly low in arm-B (351cm3 vs. 191cm3, <i>p-value</i><0.001). Radiation dose to 195cm3 of small bowel volume was 53Gy vs. 36Gy in arm-A and arm-B respectively (<i>p-value</i><0.001). Conclusion: Using belly board in prone position is comfortable, inexpensive, highly reproducible, and permits maximal bowel displacement from standard pelvic radiotherapy fields.