Original Articles: GastrointestinalUse of the Toxicity Index in Evaluating Adverse Events in Anal Cancer Trials Analysis of RTOG 9811 and RTOG 0529Kharofa, Jordan R. MD*; Yothers, Greg PhD†; Kachnic, Lisa A. MD‡; Ajani, Jaffer MD§; Meyer, Joshua E. MD∥; Augspurger, Mark E. MD¶; Okawara, Gordon S. MD#; Garg, Madhur K. MD**; Schefter, Tracey E. MD††; Swanson, Todd A. MD‡‡; Doncals, Desiree E. MD§§; Kim, Hyun MD∥∥; Zaki, Bassem I. MD¶¶; Narayan, Samir MD##; Lee, R. Jeffery MD***; Mamon, Harvey J. MD, PhD†††; Schwartz, Michael A. MD‡‡‡; Moughan, Jennifer MS†; Crane, Christopher H. MD§§§ Author Information *University of Cincinnati Cancer Center, Cincinnati §§Summa Health System—Akron Campus, Akron, OH †NRG Oncology Statistics and Data Management Center ∥Fox Chase Cancer Center, Philadelphia, PA ‡Columbia University Medical Center §§§Memorial Sloan Kettering Cancer Center, New York, NY §M D Anderson Cancer Center, Houston ‡‡University of Texas Medical Branch, Galveston, TX ¶Baptist Medical Center South, Jacksonville, FL #Juravinski Cancer Centre at Hamilton Health Sciences, Hamilton, ON **Montefiore Medical Center—Moses Campus, Bronx NY ††University of Colorado Denver, Aurora, CO ∥∥Washington University School of Medicine, Saint Louis, MO ¶¶Dartmouth-Hitchcock Medical Center, Lebanon, NH ##Saint Joseph Mercy Hospital, Ann Arbor, MI ***Intermountain Medical Center, Murray, UT †††Brigham and Women’s Hospital, Boston MA ‡‡‡Mount Sinai Medical Center, New York, NY This project was supported by grants U10CA180868 (NRG Oncology Operations), U10CA180822 (NRG Oncology SDMC), UG1CA189867 (NCORP) from the National Cancer Institute (NCI). The authors declare no conflicts of interest. Correspondence: Jordan R. Kharofa, MD, University of Cincinnati Cancer Center, 234 Goodman Street, ML 0757, Cincinnati, OH 45267. E-mail: [email protected]. Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's website, www.amjclinicaloncology.com. American Journal of Clinical Oncology: December 2022 - Volume 45 - Issue 12 - p 534-536 doi: 10.1097/COC.0000000000000955 Buy SDC Metrics Abstract Novel toxicity metrics that account for all adverse event (AE) grades and the frequency of may enhance toxicity reporting in clinical trials. The Toxicity Index (TI) accounts for all AE grades and frequencies for categories of interest. We evaluate the feasibility of using the TI methodology in 2 prospective anal cancer trials and to evaluate whether more conformal radiation (using Intensity Modulated Radiation Therapy) results in improved toxicity as measured by the TI. Patients enrolled on NRG/RTOG 0529 or nonconformal RT enrolled on the 5-Fluorouracil/Mitomycin arm of NRG/RTOG 9811 were compared using the TI. Patients treated on NRG/RTOG 0529 had lower median TI compared with patients treated with nonconformal RT on NRG/RTOG 9811 for combined GI/GU/Heme/Derm events (3.935 vs 3.996, P=0.014). The TI methodology is a feasible method to assess all AEs of interest and may be useful as a composite metric for future efforts aimed at treatment de-escalation or escalation Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.