2801 - Comparative Analysis of Radiation-Induced Proctitis in Hypofractionated vs. Conventional Pelvic Radiotherapy for Cervical Cancer: Evaluating Incidence, Risk and Mitigation Strategies
Presenter(s)
A. Mallum1, M. Tendwa2, W. Ngwa3, S. M. Avery4, S. Huq5, T. A. Ngoma6, H. Li7, J. Akudugu8, W. Swanson9, S. Seppo10, E. C. Oboh11, D. Myagmarsuren12, E. O. Olatunji13, and N. Ndlovu14; 1Walter Susilu University, Mthatha, South Africa, 2Global Health Catalyst, Boston, MA, 3John Hopkins University, Baltimore, MD, 4University of Pennsylvania, Philadelphia, PA, 5UPMC Hillman Cancer Center, Pittsburgh, PA, 6Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania, United Republic of, 7Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, 8University of Stellenbosch, Cape Town, South Africa, 9Weill Cornell Medicine, New York City, NY, 10Henry Ford Cancer Institute,, Detroit, MI, 11George Washington University School of Medicine, Washington, DC, United States, 12Virginia Tech Carilion School of Medicine, Roanoke, VA, 13Johns Hopkins Medicine, Baltimore, MD, 14University of Zimbabwe, Harare, Zimbabwe
Purpose/Objective(s): Radiation-induced proctitis (RIP), a complication of pelvic radiotherapy, poses significant challenges in cervical cancer treatment. Radiation-induced proctitis (RIP) is a significant complication arising from cervical cancer treatment. Hypofractionated radiation (HFRT), delivering larger doses in fewer sessions offers advantages such as reduced treatment duration and improved patient convenience compared to conventional fractionation (CFRT). However, the effect of HFRT on RIP incidence remains unclear. This study investigates RIP occurrence in patients receiving HFRT versus CFRT to improve risk understanding and inform mitigation strategies.
Materials/Methods: This prospective cohort study included 107 patients with histologically confirmed cervical carcinoma treated at Inkosi Albert Luthuli Central Hospital (IALCH) in South Africa between March 2022 and March 2023. Patients were randomly assigned to receive either external beam radiotherapy (EBRT) HFRT (n = 53; 42.72 Gy in 16 fractions) or CFRT (n = 54; 50.50 Gy in 25 fractions) with weekly chemotherapy, followed by booster-dose-rate intracavitary brachytherapy (HDR). The incidences of radiation proctitis and associated factors were recorded. Statistical analyses were conducted using R Statistical Computing Software (version 3.6.3). Descriptive statistics were employed to summarize numerical variables, while categorical variables were compared using chi-squared or Fisher's exact tests, as appropriate. A p-value of < 0.05 was considered statistically significant.
Results: The study cohort (median age at diagnosis: 36.4 years [range: 28.2–62.9]) comprised predominantly younger patients, with 85.0% aged <40 years and 86.0% testing positive for HIV. Most patients presented with grade II (moderately differentiated) tumors and stage IIB disease. Treatment duration differed markedly between groups: HFRT was completed in a median of 35 days versus 62 days for CFRT (p < 0.001). Comorbidities were more prevalent in the HFRT group (15.7%) than in the CFRT group (3.7%) (p = 0.001). RIP occurred in 30.8% of all patients, with significantly higher incidence in the CFRT cohort (46.2%) compared to HFRT (18.9%) (p = 0.004). Notably, proctitis incidence showed no correlation with age or comorbidity status in either group (p > 0.05).
Conclusion: These findings indicate that CFRT patients are at a higher risk of developing RIP compared to those receiving HFRT. However, further analysis of additional data is required to confirm these observations.