NUMERO: #20260014

Título: p16 immunohistochemistry evaluation as a surrogate marker of HPV-positive OPSCC in the Western Cape ,South Africa

Nome do Apresentador: Haly Holmes

Categoria do Trabalho: Pôster - Investigação Original (IO)

Área Temática: Patologia Oral

Resumo: Objective:
The positive predictive value of p16 immunohistochemistry (IHC) as a surrogate marker for HPV-associated OPSCC has been shown to be suboptimal in low High-Risk HPV (HR-HPV) prevalence populations, necessitating additional HPV-specific testing. The present study evaluates the diagnostic accuracy of p16 IHC, in comparison to the gold standard of mRNA in-situ hybridisation (RNAscope® ), in a large cohort of OPSCC patients from the Western Cape region of South Africa.

Study Design:
170 OPSCC FFPE specimens were analysed for HR-HPV using p16 IHC. p16-negative and positive OPSCC were further evaluated for the expression of HPV-16 and HPV-18 mRNA transcripts using mRNA in situ hybridisation (RNAscope®), to confirm transcriptionally active HPV. Diagnostic accuracy of p16 IHC was analysed using STATA 19.

Results:
p16 was positive in 90% (n=152) and negative in 10% (n=18) of the OPSCC specimens. 48% (n=81) of the cases were positive for mRNA ISH. One p16-negative case was mRNA ISH positive. p16 IHC showed high sensitivity (98.8%;95%CI, 93.4%-100.0%) and low specificity (19.3%;95%CI, 11.4%-99.1%).

Conclusion:
A negative p16 result reliably excludes transcriptionally active HPV infection (NPV, 94%; 95%CI, 72.7%-99.9%), while a p16 positive result is unreliable to confirm HPV-positive OPSCC (PPV, 53%; 95%CI, 45.0%-61.4%) in this region.

Autor 1:  Haly Holmes

E-mail 1:  [email protected]

Autor 2:   Siren Fromreide

E-mail 2:  [email protected]

Autor 3 :  Fabio Crabbia

E-mail 3:  [email protected]

Autor 4:  Mark E Engel

E-mail 4:  [email protected]

Autor 5:  Daniela Costea

E-mail 5:  [email protected]

Autor 6:  Amir Afrogheh

E-mail 6:  [email protected]