Faculty Collaboration Database

Intermediate-grade carcinoma of the parotid and the impact of adjuvant radiation. Am J Otolaryngol 2019;40(6):102282

Date

09/15/2019

Pubmed ID

31519432

DOI

10.1016/j.amjoto.2019.102282

Scopus ID

2-s2.0-85071985153 (requires institutional sign-in at Scopus site)   10 Citations

Abstract

PURPOSE: To determine the influence of adjuvant radiotherapy on survival in surgically-managed early stage intermediate-grade mucoepidermoid and acinic cell carcinoma of the parotid.

MATERIALS AND METHODS: The National Cancer Database was reviewed between 2004 and 2015 to identify patients with intermediate-grade, early T-stage, node-negative parotid carcinoma who underwent parotidectomy ± radiotherapy.

RESULTS: There were 744 patients identified of which 81% had mucoepidermoid carcinoma and 19% had acinic cell carcinoma. Positive surgical margins were identified in 21% and adjuvant radiotherapy was administered in 38% of cases. Of the 159 patients with positive margins, 113 (71%) received adjuvant radiotherapy. Of the 585 patients with negative margins, 173 (30%) underwent adjuvant radiotherapy. In multivariable analysis, age (over 52 years: HR 5.19, 95%CI 2.33-11.57), insurance status (private insurance: HR 0.24 95%CI 0.13-0.43), and extent of parotidectomy (total parotidectomy: HR 2.02 95%CI 1.23-3.31) were significantly associated with overall survival, while adjuvant radiotherapy was not a significant predictive factor (HR 0.81, 95%CI 0.49-1.36). In patients with positive margin resections, however, adjuvant radiation was an independent predictor of improved survival when adjusted for age, insurance status, and extent of parotidectomy (HR 0.34, 95%CI 0.13-0.88). Conversely, in patients with negative margin resections, adjuvant radiation did not influence survival outcomes when adjusted for these covariates (HR 1.02, 95%CI 0.53-1.93).

CONCLUSIONS AND RELEVANCE: In patients with early stage intermediate-grade parotid carcinoma, adjuvant radiotherapy significantly and independently improves survival in those with post-operative positive margins. Adjuvant therapy, however, does not appear to improve survival outcomes in those with negative margin resections.

Author List

North L, Stadler M, Massey B, Campbell B, Shukla M, Awan M, Schultz CJ, Shreenivas A, Wong S, Graboyes E, Pipkorn P, Zenga J

Authors

Becky Massey MD Associate Professor in the Otolaryngology department at Medical College of Wisconsin
Lauren North MD Assistant Professor in the Otolaryngology department at Medical College of Wisconsin
Christopher J. Schultz MD Chair, Professor in the Radiation Oncology department at Medical College of Wisconsin
Michael Stadler MD Associate Dean, Chief Medical Officer, Associate P in the Medical College Physicians Administration department at Medical College of Wisconsin
Stuart J. Wong MD Center Director, Professor in the Medicine department at Medical College of Wisconsin
Joseph Zenga MD Assistant Professor in the Otolaryngology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adolescent
Adult
Aged
Aged, 80 and over
Carcinoma, Acinar Cell
Carcinoma, Mucoepidermoid
Female
Humans
Male
Middle Aged
Neoplasm Grading
Neoplasm Staging
Parotid Neoplasms
Radiotherapy, Adjuvant
Retrospective Studies
Survival Rate
Young Adult