(A584) Neuroendocrine Changes in HPV+ Oropharyngeal Squamous Cell Carcinoma: A Case Series

Introduction: Patients with HPV-positive oropharyngeal squamous cell carcinoma (OPSCC) tend to have a favorable prognosis compared to HPV-negative disease. We identified a subset of patients with HPV-positive OPSCC who died from disease and re-reviewed the pathology to investigate the potential aggressive features.

Methods: Retrospective case review of patients with a history of HPV-positive OPSCC from August 2013 to July 2022 at a single institution was performed. Patient demographic criteria was collected from the chart and those who had aggressive locoregional recurrence, metastatic disease, or died from disease were selected for re-review.

Results: Nine patients met inclusion criteria and neuroendocrine features were identified in four patients (one female, three male). Neuroendocrine features were defined as a nested growth of basaloid neoplastic cells without keratinization, accompanied by the expression of neuroendocrine markers in greater than 10% of tumor cells. The mean age was 63.5 years old (range: 56-67). All patients were former smokers with metastatic disease to the bone (n=2) or lungs (n=2).

Conclusions: About 50% of patients with aggressive HPV-positive OPSCC had neuroendocrine features on review of their pathology slides. This bears significant implications in both treatment and prognosis. Further studies with larger sample sizes are needed to better understand this phenomenon and its impact on treatment strategies.