Discrepancy in p16 expression in patients with HPV-associated head and neck squamous cell carcinoma in Thailand: clinical characteristics and survival outcomes
Lalida Arsa,
Teerada Siripoon,
Narumol Trachu,
Sasithorn Foyhirun,
Duangjai Pangpunyakulchai,
Suda Sanpapant,
Natini Jinawath,
Poompis Pattaranutaporn,
Artit Jinawath,
Nuttapong Ngamphaiboon
Affiliations
Lalida Arsa
Molecular Histopathology Laboratory, Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University
Teerada Siripoon
Division of Medical Oncology, Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University
Narumol Trachu
Research center, Faculty of Medicine Ramathibodi Hospital, Mahidol University
Sasithorn Foyhirun
Immunohistopathology and Special Laboratory, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University
Duangjai Pangpunyakulchai
Immunohistopathology and Special Laboratory, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University
Suda Sanpapant
Immunohistopathology and Special Laboratory, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University
Natini Jinawath
Ramathibodi Comprehensive Cancer Center, Faculty of Medicine Ramathibodi Hospital, Mahidol University
Poompis Pattaranutaporn
Division of Radiation Oncology, Department of Radiology, Faculty of Medicine Ramathibodi Hospital, Mahidol University
Artit Jinawath
Molecular Histopathology Laboratory, Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University
Nuttapong Ngamphaiboon
Division of Medical Oncology, Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University
Abstract Background Lower prevalence HPV infection has been previously reported in Thai population when compared with Western countries. p16 expression indicates HPV-associated oropharyngeal squamous cell carcinoma (OPSCC), but not non-OPSCC. We therefore evaluated the characteristic and association of p16 and HPV in Thai patients with HNSCC. Methods We used immunohistochemistry and qPCR, respectively, to detect p16 and HPV DNA in archrival formalin-fixed paraffin-embedded HNSCC tissues. Patient characteristics and survival were analyzed. Results p16 expression was detected in tumors of 72 of 662 (10.9%) patients with HNSCC and was significantly associated with higher-grade histology, advanced nodal stage, and oropharynx. p16 was expressed in 28 and 6.5% of patients with OPSCC or non-OPSCC, respectively, and HPV DNA was detected in 15.6 and 1% of patients, respectively. Using p16 as a surrogate for HPV status, sensitivities were 80 and 25% in OPSCC and non-OPSCC, respectively. Positive and negative predictive rates of OPSCC were 38 and 95%. Discordance rates between HPV and p16 were 23 and 7% in OPSCC and non-OPSCC, respectively. Overall survival (OS) were significantly longer in both p16-positive OPSCC (p = 0.049), and non-OPSCC (p = 0.003). Conclusions Low prevalence of p16 and HPV associated OPSCC and non-OPSCC were confirmed in Thai patients. High discordance and low positive predictive rates of p16 were observed in HPV-associated OPSCC. p16 was a significant prognostic factor for OS for patients with OPSCC or non-OPSCC. Therefore, HPV testing should be performed to assess the association of HPV with HNSCC regardless of p16 expression.
