Abstract 7661: Integrating radiomic features from primary tumor and lymph node for survival prediction of HPV-associated oropharyngeal squamous cell carcinoma
Authors: Song Bolin , Leroy Amaury , Yang Kailin , Liu Qiyun , Li Xiao , Lee Jonathan , Stock Sarah , Saba Nabil F. , Lewis James S. , Deutsch Eric , Bilen Mehmet Asim , Koyfman Shlomo A. , Madabhushi Anant 
Published: March 2024

Abstract
Background: HPV-associated oropharyngeal squamous cell carcinoma (OPSCC) is a unique disease with improved prognosis which could benefit from treatment de-escalation. Current radiographic-based biomarkers mainly focus on primary tumor (PT) alone, neglecting the potential prognostic value from the lymph node (LN). In this work, we constructed a radiomic model integrating texture features from both PT and LN to predict overall survival (OS) in HPV-associated OPSCC patients.
Methods: Pretreatment CT scans for 647 OPSCC patients treated with definitive radiation with or without chemotherapy were acquired from The Cancer Imaging Archive (TCIA) and the Cleveland Clinic (CCF), which were divided into training set D1 (n=294) and test set D2 (n=353). PT and LN contours were annotated by three. 2045 texture radiomic features were extracted from both PT and LN and were concatenated as input to a LASSO Cox model to predict OS. We used the harrell’s concordance index (C-index) and hazard ratio (HR) to evaluate the prognostic performance. We also performed the multivariable cox proportional hazard analysis adjusting for clinicopathological variables to validate the independent prognostic significance.
Results: Among the 647 patients, median follow-up time was 70.23 months, with 155 patients (24%) experienced death. 22.6%, 38.8%, 23.2% and 15.4% had T stage I, II, III and IV tumors, respectively. 203 patients (31.4%) were treated with radiation alone. The model integrating PT and LN (M_PTLN) yielded higher C-index compared to PT alone (M_PT) on D1 (0.74 vs 0.66) and on D2 (0.64 vs 0.61). In univariate analysis on D2, M_PTLN is prognostic of OS (HR, 2.26; 95% CI, 1.32 - 3.87; log rank p = 0.003). In multivariable analysis, M_PTLN is still statistically significant (p = 0.04) accounting for clinicopathologic factors (age, gender, smoking pack-year [PY], T stage, N stage and treatment modality).
Conclusions: We developed and validated a CT-based survival prediction model for HPV-associated OPSCC patients with significant prognostic values, accounting for both primary tumor and lymph node. If prospectively validated, the model has the potential to inform trial eligibility and treatment-related decision making.
Citation Format: Bolin Song, Amaury Leroy, Kailin Yang, Qiyun Liu, Xiao Li, Jonathan Lee, Sarah Stock, Nabil F. Saba, James S. Lewis, Eric Deutsch, Mehmet Asim Bilen, Shlomo A. Koyfman, Anant Madabhushi. Integrating radiomic features from primary tumor and lymph node for survival prediction of HPV-associated oropharyngeal squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7661.