Rectal Dose Is the Other Dosimetric Factor in Addition to Small Bowel for Prediction of Acute Diarrhea during Postoperative Whole-Pelvic Intensity-Modulated Radiotherapy in Gynecologic Patients.
Eng-Yen HuangYu-Ming WangShih-Chen ChangShu-Yu LiuMing-Chung ChouPublished in: Cancers (2021)
We studied the association of rectal dose with acute diarrhea in patients with gynecologic malignancies undergoing whole-pelvic (WP) intensity-modulated radiotherapy (IMRT). From June 2006 to April 2019, 108 patients with previous hysterectomy who underwent WP IMRT were enrolled in this cohort study. WP irradiation of 39.6-45 Gy/22-25 fractions was initially delivered to the patients. Common Terminology Criteria for Adverse Events (CTCAE) version 3 was used to evaluate acute diarrhea during radiotherapy. Small bowel volume at different levels of isodose curves (Vn%) and mean rectal dose (MRD) were measured for statistical analysis. The multivariate analysis showed that the MRD ≥ 32.75 Gy (p = 0.005) and small bowel volume of 100% prescribed (V100%) ≥ 60 mL (p = 0.008) were independent factors of Grade 2 or higher diarrhea. The cumulative incidence of Grade 2 or higher diarrhea at 39.6 Gy were 70.5%, 42.2%, and 15.0% (p < 0.001) in patients with both high (V100% ≥ 60 mL and MRD ≥ 32.75 Gy), either high, and both low volume-dose factors, respectively. Strict constraints for the rectum/small bowel or image-guided radiotherapy to reduce these doses are suggested.
Keyphrases
- small bowel
- end stage renal disease
- rectal cancer
- early stage
- liver failure
- radiation therapy
- locally advanced
- chronic kidney disease
- irritable bowel syndrome
- ejection fraction
- newly diagnosed
- radiation induced
- peritoneal dialysis
- respiratory failure
- clostridium difficile
- drug induced
- prognostic factors
- risk factors
- aortic dissection
- acute respiratory distress syndrome
- hepatitis b virus
- intensive care unit
- mechanical ventilation
- extracorporeal membrane oxygenation
- patient reported