Validation of p16 immunocytochemical staining on alcohol-fixed aspirate smears: A single-institutional study with review of the literature.

Background: Determining human papillomavirus (HPV) status in oropharyngeal squamous cell carcinoma can have a significant impact on treatment and clinical outcomes. Because fine-needle aspiration (FNA) is typically an initial diagnostic modality in a patient workup for primary or suspected metastatic disease, immunostaining for p16 on FNA material is a promising option to determine HPV tumor status, possibly avoiding biopsies or excisions. In this study, the authors investigated the possibility of using alcohol-fixed smears as a reliable alternative for reporting p16 status.

NKX2.2, PDX-1 and CDX-2 as potential biomarkers to differentiate well-differentiated neuroendocrine tumors.

Background: Well-differentiated neuroendocrine tumors (NET) most frequently arise from the gastrointestinal tract (GI), pancreas, and lung. Patients often present as metastasis with an unknown primary, and the clinical management and outcome depend on multiple factors, including the accurate diagnosis with the tumor primary site. Determining the site of the NET with unknown primary remains challenging.