We sought to identify p16 positive, HPV negative SCCs from a large cohort of oropharyngeal SCC patients, to study their clinical and pathologic features, and to specifically compare their outcomes with tumors that are both p16 and HPV positive.

p16 (also known as p16 INK4a, cyclin-dependent kinase inhibitor 2A, CDKN2A, multiple tumor suppressor 1 and numerous other synonyms), is a protein that slows cell division by slowing the progression of the cell cycle from the G1 phase to the S phase, thereby acting as a …

Oropharyngeal cancers that contain HPV DNA (called p16-positive) tend to have a better outlook than those without HPV (p16-negative). Because p16-positive cancers have a better prognosis than p16-negative oropharyngeal cancers, separate staging systems are used. Both systems are described below.

Mar 20, 2025 · Human papillomavirus (HPV)-mediated oropharyngeal (p16+) cancer staging refers to TNM staging of squamous cell carcinomas of the oropharynx that test positive for p16, an immunohistochemical proxy for HPV infection. Nodal metastases of p16+ squamous cell carcinoma without an identified primary tumor are also staged under this system.

p16 (CDKN2A) is a member of the INK4 class of cell cycle inhibitors, which is often dysregulated in cancer. However, the prevalence of p16 expression in different cancer types is controversial. 15,783 samples from 124 different tumor types and 76 ...

Jan 25, 2024 · Strong and diffuse block staining for p16 supports a categorization of precancerous disease. Any identified p16 positive area must meet H&E morphologic criteria for a high grade lesion to reinterpreted as such. (Arch Pathol Lab Med 2012;136:1266)

P16 INK4A (also known as P16 and MTS1), a protein consisting exclusively of four ankyrin repeats, is recognized as a tumor suppressor mainly due to the prevalence of genetic inactivation of the p16INK4A (or CDKN2A) gene in virtually all types of human cancers.

Most locally advanced oropharyngeal cancers (p16/HPV-positive or p16/HPV-negative) are treated with chemoradiation. Surgery might also be an option if the surgeon thinks that the cancer can be removed safely.

Since its discovery as a CDKI (cyclin-dependent kinase inhibitor) in 1993, the tumor suppressor p16 (INK4A/MTS-1/CDKN2A) has gained widespread importance in cancer. The frequent mutations and deletions of p16 in human cancer cell lines first suggested an important role for p16 in carcinogenesis.

Mar 19, 2025 · Assessing p16 expression in SCC relies on immunohistochemistry (IHC), which detects p16 protein levels in tumor tissue. A strong, diffuse nuclear and cytoplasmic staining pattern in more than 70% of tumor cells is typically considered positive.