2857 - Outcome of Partial Laryngeal vs. Whole Laryngeal Radiation for Early Stage T1-2N0 Laryngeal Carcinoma
Presenter(s)
T. Treechairusame1,2, E. C. Dee1, Y. Yu1, D. Gelblum1, N. Riaz1, S. McBride1, L. Chen1, A. Shamseddine1, K. Zakeri1, C. J. Tsai3, J. J. Kang4, I. Ganly5, J. Cracchiolo5, S. Patel5, M. Cohen5, R. J. Wong5, and N. Y. Lee1; 1Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, 2Division of Radiation Oncology, Department of Radiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, 3Princess Margaret Cancer Centre, Toronto, ON, Canada, 4Yale University Department of Radiation Oncology, New Haven, CT, 5Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY
Purpose/Objective(s): To compare the efficacy and toxicity of partial (PLRT) and whole laryngeal radiation (WLRT) in a large cohort of early-stage laryngeal carcinoma.
Materials/Methods: A total of 233 consecutive early-stage T1-2N0M0 squamous cell carcinoma of the larynx underwent intensity modulated radiation (176 treated with WLRT vs 57 treated with PLRT) between 2013 and 2024. The main outcomes were the long-term locoregional control, laryngectomy-free, distant metastasis, and overall toxicities outcomes. Acute and late radiation toxicity were graded using Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Patient-reported swallowing-related quality of life (MD Anderson Dysphagia Inventory; MDADI) were collected at baseline, 3 months, 6 months, 12 months, and 18 months post-radiation.
Results: The median follow-up time was 58 months (IQR 24-85 months). The median follow-up in the WLRT group was 60 months (IQR 28-87 months) and in the PLRT group was 31 months (IQR 16-64 months). There was a higher proportion of T1b (WLRT 24.4% vs PLRT 0%) and T2 (WLRT 25% vs PLRT 12.3%) in the WLRT group than the PLRT group with P <0.001. There were no differences between the WLRT group and the PLRT group in terms of anterior commissure involvement (0.24), supraglottic involvement (P=0.65), subglottic involvement (P=0.12), and impaired vocal mobility (P=0.42), respectively. There were no statistically significant differences between PLRT and WLRT in 3-year local-regional control rates (90.8% vs. 85.4%, P=0.41), 3-year laryngectomy free survival (93.2% vs. 94%, P=0.74), 3-year distant metastasis-free survival (100% vs. 97.6%, P=0.29), and 3-year overall survival (91.4% vs. 88.9%, P=0.42). There was no contralateral vocal fold failure in the PLRT group. The incidence of acute dysphagia and late subcutaneous fibrosis is lower in the PLRT group than in the WLRT group (73.7% vs. 92.6%, P = 0.002, 3.8% vs 9.8%, P=0.039, respectively). Mean MDADI composite scores at 3 months and 6 months post-radiation were higher in PLRT (85.3 vs. 76.8, P=0.013, and 90.2 vs. 82.7, P =0.028, respectively).
Conclusion: PLRT is associated with lower incidence of toxicities compared to WLRT without compromising local regional control and overall survival outcomes. However, the median follow-up time in the PLRT group was relatively short, which may lead to an overestimation of the tumor control outcomes. These results warrant further prospective evaluation of PLRT for early stage glottic larynx cancer.