title: Detection of human papilloma virus and p16 expression in high-grade adenoid cystic carcinoma of the head and neck.
abstract: Squamous cell carcinoma of the head and neck, particularly basaloid squamous cell carcinoma, may be difficult to distinguish from high-grade adenoid cystic carcinoma. Evidence of human papilloma virus (HPV) infection, particularly HPV 16, is frequently found in non-keratinizing oropharyngeal squamous cell carcinoma. Immunoreactivity for p16, a surrogate marker for HPV infection, often parallels the HPV infection status in oropharyngeal squamous cell carcinoma. However, the incidence and correlation between p16 expression and HPV infection in high-grade adenoid cystic carcinoma is unknown. Sixteen cases of high-grade adenoid cystic carcinoma, three cases of dedifferentiated adenoid cystic carcinoma and eight cases of low-/intermediate-grade adenoid cystic carcinoma were identified for inclusion in the study. All cases were tested by immunohistochemistry for p16 expression and in situ hybridization for high- and low-risk HPV. Eight cases (100%) of low-to-intermediate-grade adenoid cystic carcinoma were focally positive for p16, all of which were negative for HPV. In all, 14 of 16 cases (88%) of high-grade adenoid cystic carcinoma and three cases (100%) of dedifferentiated adenoid cystic carcinoma were positive for p16; strong and diffuse staining was noted in three cases (3 of 19, 16%). Two cases (11%) of high-grade adenoid cystic carcinoma, which were also diffusely positive for p16, showed the presence of high-risk HPV. These findings suggest that the presence of HPV infection in high-grade adenoid cystic carcinoma is infrequent, even in the presence of p16 immunostaining. Nevertheless, HPV positivity should not be used to exclude the possibility of high-grade adenoid cystic carcinoma when the differential diagnosis includes squamous cell carcinoma. Moreover, although p16 overexpression is often used as a surrogate marker for HPV in squamous cell carcinoma, it cannot be used in this manner in high-grade adenoid cystic carcinoma.
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Boland
authors.forename: Ellen D
authors.initials: ED
authors.lastname: McPhail
authors.forename: Joaquín J
authors.initials: JJ
authors.lastname: García
authors.forename: Jean E
authors.initials: JE
authors.lastname: Lewis
authors.forename: David J
authors.initials: DJ
authors.lastname: Schembri-Wismayer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D003528:Carcinoma, Adenoid Cystic / Q000737:chemistry* / Q000401:mortality / Q000473:pathology / Q000821:virology*; D002454:Cell Differentiation; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000032:analysis*; D004279:DNA, Viral / Q000302:isolation & purification; D005260:Female; D006258:Head and Neck Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology / Q000821:virology*; D052162:Human papillomavirus 16 / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D008875:Middle Aged; D008910:Minnesota; D060787:Neoplasm Grading; D030361:Papillomavirus Infections / Q000150:complications / Q000401:mortality / Q000821:virology*; D011237:Predictive Value of Tests; D011379:Prognosis; D013997:Time Factors; D015854:Up-Regulation
chemical_list: D014408:Biomarkers, Tumor; D019941:Cyclin-Dependent Kinase Inhibitor p16; D004279:DNA, Viral