P27-12FREQUENCY AND CLINICAL OUTCOME OF HPV-DRIVEN OROPHARYNGEAL CARCINOMA IN NORTH-EAST ITALY

27. HPV and oropharynx / Head and neck cancer
A. Del Mistro 1, L. Baboci 1, H. Frayle 1, M. Mantovani 2, A. Menegaldo 2, G. Tirelli 3, S. Romeo 3, M.C. Da Mosto 2, P. Boscolo Rizzo 2.
1Veneto Institute of Oncology IOV - IRCCS, Immunolgy and Molecular Oncology Unit, Padova (Italy), 2Department of Neurosciences, ENT Unit, University of Padova, Treviso (Italy), 3Head and Neck Department Hospital of Cattinara, University of Trieste, Trieste (Italy)

Background / Objectives

HPV-driven oropharyngeal carcinoma (OPSCC) is on the rise in many European countries. Our objective is the assessment of frequency over time of HPV-driven OPSCC in our area and the clinical outcome in comparison to HPV-unrelated cases.


Methods

Fresh/frozen or formalin-fixed paraffin-embedded tumor specimens obtained at OPSCC diagnosis from consecutive patients (period evaluated 2003-2016) were analyzed by PCR with MY09/MY11 primers and restriction fragment length polymorphism analysis for search and typing of HPV-DNA sequences; HPV16 viral load (E6 copies/cell) was determined by real-time PCR; p16 expression was evaluated by immunohistochemistry. Presence of HPV-DNA, HPV16 viral load >1 E6 copy/cell, and p16 overexpression defined an OPSCC as HPV-driven. Frequency of HPV-driven OPSCC was calculated overall and by time periods (2003-2007; 2008-2012; 2013-2016). Overall Survival (OS) and Progression Free Survival (PFS) were calculated by Kaplan-Meier method and Cox-regression and compared among patients with HPV-driven and HPV-unrelated OPSCC.


Results

Overall, 101 cases of newly diagnosed OPSCC were included; data on 63 of them have been previously published (1-3). HPV-DNA sequences were detected in 31 of them; HPV16 was present in 29, and HPV58 and HPV33 in 1 case each. Up to now, the causal role of HPV has been proven in 28 cases (26 HPV16, 1 HPV58 and 1 HPV33). The prevalence of HPV-driven OPSCC in the three time periods was 17.4% (4/23), 25.6% (10/39) and 35.9% (14/39), respectively (P=.109). Patients with HPV-driven tumors had both improved OS (HR = 0.25, 95% CI = 0.10 to 0.62; P=.003) and PFS (HR = 0.23, 95% CI = 0.10 to 0.55; P=.001).


Conclusion

The frequency of HPV-driven OPSCC is on the rise also in North-East Italy, an area with known low prevalence. Our data confirm the good prognosis of patients with HPV-driven OPSCC.


References

1) Boscolo-Rizzo P, Da Mosto MC, Fuson R, Frayle-Salamanca H, Trevisan R, Del Mistro A. HPV-16 E6 L83V variant in squamous cell carcinomas of the upper aerodigestive tract. J Cancer Res Clin Oncol 2009;135:559-566.

2) Baboci L, Boscolo-Rizzo P, Holzinger D, Bertorelle R, Biasini L, Michel A, Schmitt M, Spinato G, Bussani R, Alemany L, Tirelli G, Da Mosto MC, Del Mistro A, Pawlita M. Evidence of the causal role of human papilloma virus type 58 in an oropharyngeal carcinoma. Virol J 2013;10:334.

3) Baboci L, Holzinger D, Boscolo-Rizzo P, Tirelli G, Spinato R, Lupato V, Fuson R, Schmitt M, Michel A, Halec G, Da Mosto MC, Pawlita M, Del Mistro A. Low prevalence of HPV-driven head and neck squamous cell carcinoma in North-East Italy. Papillomavirus Res 2016;2:133-140.