Affiliation:
1. National Cancer Center, National Clincial Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences (CAMS) and Peking Union Medical College (PUMC)
2. Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University
3. National Cancer Center, Chinese Academy of Medical Sciences (CAMS) and Peking Union Medical College (PUMC)
Abstract
Abstract
Purpose: To evaluate prognosis for reducing postoperative radiotherapy (PORT) dose to lymph node levels of supraglottic cancer (SC) on real-word data.Method and materials: Patients were derived from two cancer centers. In center 1, the involved nodal levels (high-risk levels, HRL) and the next level received a dose of 60.06Gy/1.82Gy per fraction, while the other uninvolved levels (low-risk levels, LRL) received 50.96Gy/1.82Gy per fraction. In center 2, all received 50Gy/2Gy per fraction. The rates of high-risk levels control (HRC), regional control (RC), overall survival (OS), progression-free survival (PFS) and distant metastasis-free survival (DMFS) were calculated by Kaplan-Meier method. Result: Totally, 124 patients were included (62 in center 1, 62 in center 2). Most patients (106, 85.5%) had a stage T3/N+ tumor. The median follow-up was 45 months (range 1-163 months). There were no significant differences in terms of OS (p=0.126), RC (p=0.514), PFS (p=0.195) and DMFS (p=0.834). Most regional recurrences (4, 80%) occurred within three years of treatment, and all occurred within the target volumes. No regional failure occurred in HRL in center 1, while three (3/4) failures occurred in center 2. Dose reduction prescription to HRL led to a lower HRC rate (100% vs. 90.6%, p=0.009). While the rates of LRL control (98.4%) were equal between the two centers.Conclusion: Compared with a standard dose, the reduced dose to involved nodal levels showed inferior regional control for PORT, while uninvolved nodal levels showed equal outcomes. A dose of 50Gy for HRL may be an unfavorable treatment option for SC.
Publisher
Research Square Platform LLC