[1231] Carcinoma In Situ and p16 Status of Head and Neck Squamous Cell Carcinomas

VY Jo, SM O'Connor, MH Stoler, EB Stelow. University of Virginia, Charlottesville, VA

Background: The etiologic relationship of Human Papillomavirus (HPV) and squamous cell carcinoma (SCC) in the upper aerodigestive tract (UADT) is well-established. The majority of HPV-associated SCCs are non-keratinizing and located in the oropharynx (base of tongue and palatine tonsil), and are known to have a better prognosis than non-HPV-associated SCCs. Here, we report the presence of either immature or maturing / keratinizing carcinoma in situ (CIS) in a case-controlled series of p16-immunoreactive and nonreactive UADT SCCs.
Design: Consecutive biopsies of SCC in the UADT with available p16 immunohistochemistry that were diagnosed between 2007-2009 were reviewed. All cases were examined for the presence of immature CIS (non-keratinizing and similar in appearance to cervical CIS) or maturing / keratinizing CIS. Immunohistochemistry had been performed using an antibody to p16INK4 (CINtec, MTM Laboratories), and cases interpreted as positive demonstrated nuclear and cytoplasmic staining in greater than 60% of tumor cells.
Results: 132 biopsy cases of SCC were identified (104 men and 28 women; average age 57.9 years). 57 cases were p16-immunoreactive. These were distributed as follows: hypopharynx (1), larynx (12), nasal cavity (1), nasopharynx (1), oral cavity (4), oropharynx (37), and sinonasal (1). Of the p16-immunoreactive SCCs, 35 cases were associated with immature CIS and 16 tumors were associated with maturing / keratinizing CIS. 75 biopsy cases were p16-nonreactive. These were distributed as follows: hypopharynx (5), larynx (31), oral cavity (22), oropharynx (15), and sinonasal (2). Of the p16-nonreative SCCs, 10 cases were associated with immature CIS and 46 tumors were associated with maturing / keratinizing CIS. Immature CIS was more frequently seen in the p16-immunoreactive SCCs (p<0.01).
Conclusions: This biopsy series of SCCs in the UADT shows the expected location distribution of p16-immunoreactive UADT SCCs, which occur more frequently in the oropharynx. Furthermore, immature CIS is observed significantly more frequently in association with p16-immunoreactive tumors. This feature may be used to help triage cases of UADT SCC toward p16 and HPV testing.
Category: Head & Neck

Tuesday, March 23, 2010 1:00 PM

Poster Session IV # 156, Tuesday Afternoon

 

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