The impact of boost radiation therapy after hysterectomy on cervical cancer patients with close or positive resection margins

Purpose: We investigated the effect of boost radiation therapy (RT) in addition to whole pelvis RT (WPRT) on treatment outcome and safety of cervical cancer patients following hysterectomy with close/positive resection margins (RM). Methods: We retrospectively analyzed 51 patients with cervical cancer who received WPRT with or without boost-RT as adjuvant treatment between July 2006 and June 2022. Twenty patients (39.2%) were treated with WPRT-alone, and 31 (60.8%) received boost-RT after WPRT using brachytherapy or intensity-modulated RT. Results: The median follow-up period was 41 months. According to RT modality, the 4-year local control (LC) and locoregional control (LRC) rates of patients treated with WPRT-alone were 61% and 61%, respectively, whereas those in LC and LRC rates in patients who underwent WPRT with boost-RT were 93.2% and 75.3%, with p-values equal to 0.005 and 0.090, respectively. Seven patients (35.0%) had local recurrence in the WPRT-treated group compared to only two out of the 31 patients (6.5%) in the WPRT with boost-RT-treated counterparts (p = 0.025). Boost-RT was a significantly good prognostic factor for LC (p = 0.013) and LRC (p = 0.013). Boost-RT did not result in statistically-significant improvements in progression-free survival or overall survival. The acute and late toxicity rates were not significantly different between groups. Conclusion: Boost RT following WPRT is a safe and effective treatment strategy to improve LC without increasing toxicity in patients with cervical cancer with close/positive RM after hysterectomy.