Abstract
Introduction: The association of HPV infection with oropharyngeal squamous cell carcinoma (SCC) is well-established and portends better survival when compared to patients with HPV-negative ones. We had previously shown that p16 expression by immunohistochemistry (IHC), a surrogate for HPV oncoprotein function, is quite prevalent in mesenchymal tumors as well as sarcomatoid carcinoma of the head and neck. The goal of this study is to evaluate head and neck mesenchymal tumors and sarcomatoid carcinomas for HPV using HPV chromogenic in-situ hybridization (CISH). Design: Previously identified 50 cases with P16 testing (21 sarcomatoid carcinoma, 28 mesenchymal tumors and one poorly differentiated malignant neoplasm), were tested using CISH probes for HPV (HPV 16, 18 and 33). The mesenchymal group included embryonal rhabdomyosarcoma, epithelioid sarcoma, osteosarcoma, chondrosarcoma, malignant peripheral nerve sheet tumor, Ewings sarcoma, dedifferentiated liposarcoma, synovial sarcoma, Fibrosarcoma and Pleomorphic undifferentiated sarcoma. Slides were evaluated using bright field microscopy and the proportion of staining cells was recorded. Results:HPV CISH was negative (<1% of cells) in all mesenchymal tumors as well as all sarcomatoid carcinomas. This is in comparison to our previously reported rates of P16 positivity; 17/28 (61%) of mesenchymal tumors and 5/21 (24%) sarcomatoid carcinomas. Conclusion:HPV is not associated with sarcomatoid carcinoma nor with mesenchymal tumors of the head and neck, which suggests that P16 is not a reflection of HPV status in this cohort of tumors. The prognostic significance of P16 in these tumors should be further evaluated.
Financial Disclosure:
No current or relevant financial relationships exist.
