(138) Diagnostic Dilemma of FNAs in p16+ OPSCC Unknown Primary Work-Up

Monday, October 2, 2023

2:45 PM – 3:45 PM East Coast USA Time

Presenting Author(s)

DL

Doreen W. Lam, BA

Medical Student
Perelman School of Medicine, University of Pennsylvania
Philadelphia, PA, United States

Co-Author(s)

DB

Devraj Basu, MD, PhD

Department of Otorhinolaryngology – Head & Neck Surgery, University of Pennsylvania, USA
SC

Steven B. Cannady, MD

Assistant Professor of Otorhinolaryngology: Head and Neck Surgery
Department of Otorhinolaryngology – Head & Neck Surgery, University of Pennsylvania
Philadelphia, PA, United States
AC

Ara A. Chalian, MD

Professor, ORL/HNS, Hospital Patient Safety Officer
Department of Otorhinolaryngology – Head & Neck Surgery, University of Pennsylvania
philadelphia, Pennsylvania, USA
Karthik Rajasekaran, MD

Assistant Professor, Head and Neck Oncologic & Reconstructive Surgeon, Director of QI
Department of Otorhinolaryngology – Head & Neck Surgery, University of Pennsylvania
Philadelphia, Pennsylvania, United States
GW

Gregory S. Weinstein, MD

Professor
Department of Otorhinolaryngology – Head & Neck Surgery, University of Pennsylvania
Philadelphia, Pennsylvania, USA

Senior Author(s)

RB

Robert M. Brody, MD

Assistant Professor
Department of Otorhinolaryngology – Head & Neck Surgery, University of Pennsylvania
Philadelphia, Pennsylvania, United States

Disclosure(s):

Steven B. Cannady, MD: No relevant relationships to disclose.

Karthik Rajasekaran, MD: No relevant relationships to disclose.

Robert M. Brody, MD: No relevant relationships to disclose.

Introduction: Fine needle aspiration (FNA) is commonly utilized for the initial work-up of oropharyngeal squamous cell carcinoma (OPSCC) of unknown primaries but is frequently nondiagnostic. In this study, we characterize sensitivity of FNAs in SCC diagnosis, review diagnostic methods after nondiagnostic results and assess impact on time to treatment.

Methods: A retrospective cross-sectional study was performed on p16+ OPSCC of unknown primary patients treated with primary transoral robotic surgery (TORS) between October 2011 and June 2022 at a single institution. Demographics, diagnostic work-up, surgical management and pathology results were abstracted via chart review. Analysis was performed in R Studio.

Results: 137 patients met inclusion criteria. 121 (88%) underwent initial FNA. Of those, 70 (58%) were positive for SCC, 34 (28%) suspicious but inconclusive, and 17 (14%) nondiagnostic. 41 (34%) underwent p16 staining.

SCC diagnosis after nondiagnostic or suspicious FNAs were made via excisional lymph node biopsy (49%), repeat FNA (29%) or core needle biopsy (10%). 10% underwent unknown primary TORS after suspicious FNA and PET findings without further biopsies. 2% were diagnosed with presumed HPV-associated OPSCC via positive ctHPVDNA assay by NavDx test after nondiagnostic FNA and benign excisional biopsy.

Kruskal-Wallis rank sum test showed nondiagnostic FNAs led to delayed first head and neck surgical oncologist (H&N) appointment when compared to definitive or suspicious results (median = 58 vs 15, 19 days; p = < 0.001) and TORS (98 vs 38, 60; p = < 0.001), with no difference in time between H&N consultation and definitive surgery.

Conclusions: Obtaining definitive SCC diagnosis via FNA can be challenging with 58% sensitivity. Excisional biopsy was the most common diagnostic method following nondiagnostic and suspicious FNAs. We found nondiagnostic FNAs led to significant delays in H&N referral and TORS by an additional 39 and 38 days compared to suspicious FNAs.

Further studies are warranted to define evidence-based pathways for timely p16+ OPSCC diagnosis after nondiagnostic FNAs to reduce treatment delays.