Diagnostic Accuracy of HPV Circulating Tumor DNA Following Non-Diagnostic FNA of a Cystic Lateral Neck Mass.

Abstract

Cystic lateral neck masses in adults commonly represent nodal metastases from HPV-associated oropharyngeal squamous cell carcinoma (OPSCC) or benign lesions. Because cystic lesions are relatively acellular, fine-needle aspiration (FNA) is often non-diagnostic. HPV circulating tumor DNA (ct-DNA) may aid diagnosis in these cases. We conducted a two-institution retrospective review of patients with cystic neck masses and non-diagnostic FNA who underwent pre-treatment HPV ct-DNA testing. Sensitivity, specificity, and predictive values were calculated based on final pathology. Thirty-two patients were included. HPV ct-DNA was positive in 20/32 (62.5%) cases, all of which were HPV-associated OPSCC. Four patients with negative HPV ct-DNA were ultimately diagnosed with HPV-associated OPSCC (sensitivity: 83%, specificity: 100%, PPV: 100%, NPV: 67%). HPV ct-DNA demonstrated high specificity and may complement standard workup in adult cystic neck masses with non-diagnostic FNA. Positive HPV ct-DNA results should prompt further evaluation for HPV-associated OPSCC.