title: Duodenal and other gastrointestinal toxicity in cervical and endometrial cancer treated with extended-field intensity modulated radiation therapy to paraaortic lymph nodes.
abstract: OBJECTIVE
  To characterize the rates of acute and late duodenal and other gastrointestinal (GI) toxicities among patients treated for cervical and endometrial cancers with extended-field intensity modulated radiation therapy (EF-IMRT) to the paraaortic nodes and to analyze dose-volume relationships of GI toxicities.
  
  
  METHODS
  Fifty-three patients with endometrial or cervical cancer underwent EF-IMRT to the paraaortic nodes, of whom 46 met the inclusion criteria for GI toxicity and 45 for duodenal toxicity analysis. The median prescribed dose to the paraaortic nodes was 54 Gy (range, 41.4-65 Gy). The 4 duodenal segments, whole duodenum, small bowel loops, peritoneum, and peritoneum plus retroperitoneal segments of colon were contoured retrospectively, and dosimetric analysis was performed to identify dose-volume relationships to grade ≥3 acute (<90 day) and late (≥90 day) GI toxicity.
  
  
  RESULTS
  Only 3/46 patients (6.5%) experienced acute grade ≥3 GI toxicity and 3/46 patients (6.5%) experienced late grade ≥3 GI toxicity. The median dose administered to these 6 patients was 50.4 Gy. One of 12 patients who received 63 to 65 Gy at the level of the renal hilum experienced grade 3 GI toxicity. Dosimetric analysis of patients with and without toxicity revealed no differences between the mean absolute or fractional volumes at any 5-Gy interval between 5 Gy and the maximum dose. None of the patients experienced duodenal toxicity.
  
  
  CONCLUSIONS
  Treatment of paraaortic nodes with IMRT is associated with low rates of GI toxicities and no duodenal-specific toxicity, including patients treated with concurrent chemotherapy. This technique may allow sufficient dose sparing of the bowel to enable safe dose escalation to at least 65 Gy.
authors.affiliation: Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Philip D
authors.initials: PD
authors.lastname: Poorvu
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Sadow
authors.forename: Kanokpis
authors.initials: K
authors.lastname: Townamchai
authors.forename: Antonio L
authors.initials: AL
authors.lastname: Damato
authors.forename: Akila N
authors.initials: AN
authors.lastname: Viswanathan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001011:Aorta; D002945:Cisplatin / Q000009:adverse effects / Q000627:therapeutic use; D003106:Colon / Q000528:radiation effects; D003131:Combined Modality Therapy / Q000009:adverse effects / Q000379:methods; D004307:Dose-Response Relationship, Radiation; D004386:Duodenum / Q000528:radiation effects; D016889:Endometrial Neoplasms / Q000188:drug therapy / Q000532:radiotherapy*; D005260:Female; D041981:Gastrointestinal Tract / Q000528:radiation effects*; D006801:Humans; D007421:Intestine, Small / Q000528:radiation effects; D015182:Lymphatic Irradiation; D008875:Middle Aged; D058958:Organs at Risk / Q000528:radiation effects*; D011832:Radiation Injuries / Q000473:pathology*; D011838:Radiation-Sensitizing Agents / Q000009:adverse effects / Q000627:therapeutic use; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects* / Q000379:methods; D012189:Retrospective Studies; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy / Q000532:radiotherapy*
chemical_list: D011838:Radiation-Sensitizing Agents; D002945:Cisplatin