Abstract LB-445: Human papillomavirus (HPV) status is a long-term survival indicator for patients with oropharyngeal cancers in British Columbia

Abstract

Abstract The incidence of oropharyngeal squamous cell carcinoma (OpSCC) is increasing worldwide. In British Columbia, similar trend is observed. High-risk HPV and p16 have been used as prognostic markers in OpSCC; however, due to the difference in HPV detection methods, the results have been indeterminate. In BC, we do not routinely stain for p16 or investigate tumoral HPV status. This is the first time to link these data with treatment and outcome information. Objectives: To determine HPV status and expression of cyclin D1, p16 and EGFR of OpSCC and their impact on survival. Methods: Patients (N = 151) with primary OpSCC and treated with intent-to-cure at the Vancouver Centre from 2001 to 2007 were retrospectively identified from Pathology database. Outcome data was collected through electronic chart review. Among these patients, 100 (66 %) patients had no recurrence or died without disease at last follow-up (better outcome, Group1) and 50 (33%) patients had persistent disease or died of disease (poorer outcome, Group 2). The high-risk HPV status was determined using Chromogenic in situ hybridization (CISH) (DAKO, Denmark) and expression of p16, EGFR, and cyclin D1 were analyzed using immunohistochemistry. Results: There was no difference in gender, smoking habit, and tumor staging between Groups 1 and 2. However, Group 1 had a significant longer follow-up time comparing to those of Group 2 (50 ± 20 vs. 29 ± 21 months; P < 0.0001). Group1 was 5 years younger than Group 2 (55.5 ± 9.4 vs. 60.1 ± 9.7 years, P= 0.001). HR-HPV had been found in 70% of all cases (N = 105). Group 1 showed significantly higher HR-HPV infection (77% vs. 54%, P = 0.005), more p16 overexpression (80% vs. 64%, P = 0.05), and less cyclin D1 overexpression (16% vs. 36%, P = 0.007). There was no difference observed in EGFR expression. Using Cox Proportional Hazard model for age, sex, treatment type (Surgery and/or radiation, radiation only, combined chemo and radiation therapy), tumor staging (early and late), HPV status, p16, cyclin D1, and EGFR expression, only HPV status (p = 0.0003) and age (p = 0.011) were found to be significant predictors of 5- year survival. After adjusting the age variable, HPV positive patients were 65% less likely to die compared to those HPV negative patients. Those patients with cyclinD1 positive tumors have a 2.8 time elevated risk to die of disease. Conclusion: High frequency of high-risk HPV is identified in OpSCC in British Columbia. Presence of HPV and younger ages have better outcome. The presence of high-risk HPV is an independent factor to long-term survival. (Canadian Cancer Society CCSRI-20336 and BC Cancer Foundation) Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr LB-445. doi:1538-7445.AM2012-LB-445