Does Margin Distance Impact Recurrence in the De-escalation Era of Oropharyngeal Squamous Cell Carcinoma?

Saturday, September 28, 2024

9:36 AM – 9:42 AM EDT

Location: MBCC, 208

Disclosure(s):

Gabriela A. Calcano, BS:

faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Katelyn S. Rourk, BS:

faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Kathryn M. Van Abel, MD:

faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Introduction: Margin distance is a significant prognosticator in oral cavity cancer. In HPV-related oropharyngeal cancer (HPV(+)OPSCC), margin distance has been considered an intermediate risk factor in surgical de-escalation trials, but its prognostic value remains unclear. Here, we investigate the impact of margin distance on locoregional recurrence in HPV(+)OPSCC treated with standard and de-escalated adjuvant radiotherapy.

Methods: This is a retrospective cohort study of HPV(+)OPSCC patients treated at a single tertiary care institution with primary surgical therapy. De-escalated adjuvant radiotherapy was delivered at 30-36Gy with concurrent docetaxel, on and off clinical trial. Margin distance was measured in mm, from the primary specimen alone or in combination with separately submitted margins. Kaplan-Meier survival analysis was performed using locoregional and local recurrence as the primary outcome. Univariate and multivariable Cox regression analysis was conducted to determine the impact of margin distance and degree of adjuvant treatment on risk of recurrence.

Results: Of 361 patients, 335 (92.7%) had negative margins. Margin distance was >3mm in 71.6%, 1-3mm in 25.7%, and <1mm in 2.7% of patients. 37 locoregional recurrences occurred over a median follow-up of 3.5 years, 21 of which were local. The 5-year locoregional recurrence rate was 12%. Patients who received adjuvant radiotherapy (HR:0.20, 95%CI: 0.07-0.57x, p=.003) or adjuvant chemoradiation (HR: 0.23, 95%CI: 0.12-0.47, p<.0001) were less likely to develop locoregional recurrence compared to those who received surgery alone. Close surgical margins of 1-3mm and <1m had no significant impact on locoregional or local recurrence alone compared to margins of >3mm. In multivariable modeling, close surgical margins <3mm did not significantly impact locoregional recurrence even after adjusting for de-escalated adjuvant therapy (p=.64).

Conclusions: Close surgical margins <3mm are not a significant driver of locoregional recurrence in HPV(+)OPSCC, even in the era of de-escalated adjuvant therapy.

Presenting Author(s)

Gabriela A. Calcano, BS

Medical Student
Icahn School of Medicine at Mount Sinai
Rochester, Minnesota, United States

Disclosure(s):
faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Co-Author(s)

Katelyn S. Rourk, BS

Medical Student
Mayo Clinic Alix School of Medicine
Rochester, Minnesota, United States

Disclosure(s):
faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.
KV

Kathryn M. Van Abel, MD

Associate Professor
Mayo Clinic Department of Otolaryngology-Head and Neck Surgery
ROCHESTER, MN, United States

Disclosure(s):
faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.
DR

David M. Routman, MD

Mayo Clinic Department of Radiation Oncology, United States

Disclosure information not submitted.
JO

Jamie J. O'Byrne, MS

Biostatistician
Mayo Clinic Department of Quantitative Health Sciences
Rochester, MN, United States

Disclosure information not submitted.
Aaron W. Bogan, MA

Senior Biostatistician
Mayo Clinic Department of Health Sciences Research, Division of Biostatistics
Scottsdale, AZ, United States

Disclosure information not submitted.

Senior Author(s)

Linda X. Yin, MD

Resident Physician
Mayo Clinic Department of Otolaryngology-Head and Neck Surgery
Rochester, Minnesota, United States

Disclosure information not submitted.