A multi-institutional acute gastrointestinal toxicity analysis of anal cancer patients treated with concurrent intensity-modulated radiation therapy (IMRT) and chemotherapy

Using previous dosimetric analysis methods, we identified the volume of bowel receiving 30 Gy (V30) correlated with acute gastrointestinal (GI) toxicity in anal cancer patients treated with intensity-modulated radiation therapy and concurrent chemotherapy. For V30 > 450 cc and ⩽450 cc, acute GI toxicity was 33% and 8%, respectively (p = 0.003).