NEUROENDOCRINE DIFFERENTIATION AND CELL PROLIFERATION IN ORAL AND OROPHARYNGEAL SQUAMOUS CELL CARCINOMA

Abstract

Objective Squamous cell carcinoma (SCC) of the head and neck region with neuroendocrine differentiation are rare neoplasms. These tumors can be poorly differentiated and usually have tendency for aggressive clinical behavior and propensity for both regional and distant metastasis. Their diagnosis is based on morphology and confirmation of origin by immunohistochemistry. The purpose of this study was to investigate the neuroendocrine differentiation profile in oral SSC (OSCC) and oropharyngeal SCC (OPSCC). Study Design One hundred thirteen cases (male, n = 95; female, n = 18; mean age, 60.4 years) diagnosed with OSCC (n = 85) and OPSCC (n = 28) were selected. Immunohistochemistry was performed using the tissue microarray technique to evaluate the immunomarkers chromogranin-A, synaptophysin, CD56, CD57, CD99, Ki-67, and cyclin D1. Results Our results showed positivity for chromogranin-A (8.3% OSCC; 0% OPSCC), synaptophysin (9.5% OSCC; 0% OPSCC), CD99 (28.8% OSCC; 3.8% OPSCC) and CD56 (1.2% OSCC; 11.1% OPSCC). CD57 was negative. The Ki-67 was 43.6% and 42.0% and cyclin D1 was 33.7% and 26.6% in OSCC and OPSCC, respectively. Conclusions Our results show similar proliferation index in both OSCC and OPSCC, and that neuroendocrine differentiation can be detected in some cases of OSCC and OPSCC and should be reclassified as such. FAPESP grant: 2016/11419-0.