2018-19 Section 7-Neoplastic and Inflammatory Diseases of the Head and Neck eBook

Reprinted by permission of Oral Oncol. 2017; 73:152-159.

Oral Oncology 73 (2017) 152–159

Contents lists available at ScienceDirect

Oral Oncology

journal homepage: www.elsevier.com/locate/oraloncology

Appraisal of the AJCC 8th edition pathologic staging modi fi cations for HPV − positive oropharyngeal cancer, a study of the National Cancer Data Base Kevin Y. Zhan a , 1 , Antoine Eskander b , 1 , Stephen Y. Kang a , Matthew O. Old a , Enver Ozer a , Amit A. Agrawal a , Ricardo L. Carrau a , James W. Rocco a , Theodoros N. Teknos a , ⁎ a Department of Otolaryngology – Head & Neck Surgery, Division of Head & Neck Oncology, The Ohio State University, James Cancer Center and Solove Research Institute, Columbus, OH, USA b Department of Otolaryngology – Head & Neck Surgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada

MARK

A R T I C L E I N F O

A B S T R A C T

Background: The American Joint Commission on Cancer (AJCC) recently created new staging for human pa- pillomavirus associated oropharyngeal cancer (HPV+ OPSCC) for its 8th edition. These proposals have not yet been validated in a national registry. Methods: Review of National Cancer Database (NCDB) for surgically-treated HPV+ OPSCC for years 2010 – 2014 to validate the new staging system using the Kaplan Meier method to explore survival outcomes. Results: 3745 cases were analyzed. Median follow-up was 31.3 months. Most patients were Caucasian males with tonsillar cancer. Distribution of stage I disease increased from 3.7% to 80.2% in AJCC 8th. pN1 disease shifted from 17.3% to 75.9%. Treatment and distribution of T-stage varied by pathologic nodal (pN) staging. Extranodal extension (ENE) was positive in 41% cases. Four-year overall survival (OS) for AJCC 8th stages I (92%), II (81%), and stage III (62%) showed excellent hazard discrimination (all pairwise p < 0.001). Only 4- year OS by pN staging showed signi fi cantly di ff erent curves when comparing pN2 (79%) with others (pN0 88%; pN1 91%, p = 0.01 and <0.001 respectively). Presence of ENE confers a negative e ff ect on overall survival (92% ENE − vs. 85% ENE+, p < 0.001). Conclusion: The NCDB shows improved hazard discrimination and outcome prediction in the AJCC 8th edition staging for HPV+ OPSCC. While overall staging had excellent hazard discrimination, this accounted for poorer discrimination between pN0 and pN1. The majority of patients are reclassi fi ed as overall stage I. Presence of extranodal extension demonstrated a statistically signi fi cant but modest negative e ff ect on overall survival. Condensed abstract (2 sentences): Using NCDB data for validation, the AJCC 8th ed. pathologic staging system o ff ers much improved hazard discrimination and prognostication in HPV oropharyngeal cancer, with the ma- jority of cases reclassi fi ed as pStage I. Of note, only pN2 o ff ered hazard discrimination within nodal staging and presence of pathologic extranodal extension has a modest negative e ff ect on survival.

Keywords: Staging AJCC Oropharynx cancer HPV p16 Tonsil cancer Base of tongue cancer Head and neck cancer Extranodal extension NCDB

Introduction

disease. Moreover, recent studies have demonstrated its prognostic in- adequacy [2 – 5] . Fears of HPV+ OPSCC overtreatment from advanced stage classi fi cation in the 7th edition have lead to treatment de-esca- lation clinical trials and further need for HPV speci fi c staging [6] . The new 8th edition of the AJCC staging manual introduced two distinct clinical and pathologic staging paradigms speci fi c to HPV+ OPSCC, to be implemented starting January 2018 [7] . Recent literature contributing to these changes are multicenter, multinational studies with patients managed primarily with either surgery or radiation

The American Joint Commission on Cancer (AJCC) 7th edition staging manual for oropharyngeal cancer was designed before high-risk human papillomavirus positive oropharyngeal cancer (HPV+ OPSCC) became preeminent, an entity that ’ s now expected to surpass incidence of HPV cervical cancer by 2020 [1] . As such, the 7th edition staging paradigm progressively lost its prognostic ability as HPV+ OPSCC boasts far better survival and treatment sensitivity than HPV − negative

⁎ Corresponding author at: Department of Otolaryngology – Head & Neck Surgery, James Cancer Hospital and Solove Research Institute, 456 West 10th Avenue, Room #4a, Columbus, OH 43210, USA.

1 These two authors are co- fi rst authors having contributed equally to this work. E-mail address: ted.teknos@osumc.edu (T.N. Teknos).

http://dx.doi.org/10.1016/j.oraloncology.2017.08.020 Received 18 May 2017; Received in revised form 29 August 2017; Accepted 31 August 2017

Available online 07 September 2017 1368-8375/ © 2017 Published by Elsevier Ltd.

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