← Back to List

Program Number: B253
Session Name: Poster Session

18F-FDG PET CT-Derived Features as Predictors of Tumor Staging and Recurrence-Free Survival in HPV-Associated Oropharyngeal Squamous Cell Carcinoma

Raksha Kulkarni, MD; Megan Tang, BA; Peter Cooke, MD; Susmita Chennareddy, BA; Joseph Correa, BA; Daniel Kraft, MD; Raymond Chai, MD; Scott Roof, MD; Nasrin Ghesani, MD; Icahn School of Medicine at Mount Sinai

Background: Data suggests that volumetric parameters derived from ¹⁸F-FDG PET CT scans can augment prognostication of HPV-driven oropharyngeal squamous cell carcinoma (OPSCC). We aim to assess whether pretreatment PET features are associated with tumor staging and recurrence-free survival (RFS) in HPV+ OPSCC patients.

Methods: This retrospective cohort study analyzed patients with HPV+ OPSCC treated between April 2020 and September 2024 at a single institution. To assess baseline PET features, voxels of interest (VOIs) were drawn around lesions on pretreatment PET CT images. Parameters for the primary tumor, nodes, and overall tumor burden were then derived using MIM™ software. Our ¹⁸F-FDG PET CT-derived parameters included the mean and maximum standardized uptake values (SUVmean and SUVmax, respectively), representing FDG uptake; total metabolic tumor volume (TMTV), which quantifies disease burden; and tumor lesion glycolysis (TLG), a measure of the extent of tumor metabolic activity.

Kendall’s tau associations between PET metrics and tumor, nodal, and overall staging (AJCC 8th Edition) were identified. Univariate analyses and Cox proportional hazard models were performed to examine PET predictors of RFS, defined as the number of months from treatment completion to any first detection of recurrence. Statistical significance was defined as p-value<0.05.

Results: Our study included 191 patients with a median 26.7 months of follow-up after treatment completion. Overall cancer staging was associated with higher SUVmax, TLG, and TMTV of the primary tumor, as well as higher SUVmean of the total tumor burden (p<0.01 for all). Within the overall staging, primary tumor staging was associated with higher SUVmean, SUVmax, TLG, and TMTV for the primary and total tumor burden (p<0.01). Nodal staging was also associated with higher TLG and TMTV of the primary tumor and nodes (p<0.01).

29 (15.2%) of patients developed recurrent HPV+ OPSCC after a median 6.7 months following treatment completion (Figure 1). Higher baseline primary tumor SUVmax was associated with decreased time to recurrence (Pearson’s r = -0.42, p=0.02). When including overall cancer staging as a covariate, primary tumor SUVmax demonstrated a hazard ratio of 1.1 (95% CI 1.05-1.27; p<0.01) in predicting recurrence. After dividing patients into two groups (n=86 each) relative to the median primary tumor SUVmax value, recurrence was seen in 19 (22.1%) patients with above-median SUVmax and 10 (11.6%) patients with below-median SUVmax values. Patients with an above-median primary tumor SUVmax showed decreased RFS, though this difference was not statistically significant (p=0.06; Figure 2). Wilcoxon rank-sum tests demonstrated that primary tumor TLG and TMTV (p<0.01 for both) and total tumor SUVmean (p=0.04), SUVmax (p<0.01), TLG (p<0.01), and TMTV (p<0.01) were significantly higher in patients with recurrence than in those without recurrence.

Conclusions: The association of SUV, TLG, and TMTV with tumor stage, and the association of primary tumor SUVmax with recurrence, suggests a strong prognostic value for ¹⁸F-FDG PET CT at initial staging and surveillance of HPV+ OPSCC.

Figure 1. Recurrence-free survival for the full patient cohort. Two patients experienced recurrence prior to treatment completion. 

Figure 2. Recurrence-free survival for patients with primary tumor SUVmax above vs. below the median value.

 

 

← Back to List