Gender disparities in salivary malignancies: Is gender impacting oncological outcomes?

Presentation: AHNS-041
Topic: Salivary
Type: Oral
Date: Thursday, May 2, 2019
Session: 6:00 AM - 7:00 AM Scientific Session 5 - Value I
Authors: Ximena Mimica, MD, Marlena McGill, BS, Ashley Hay, MD, Daniella K Zanoni, MD, Jatin P Shah, MD, Richard J Wong, Marc A Cohen, MD, Snehal G Patel, MD, Ian Ganly, MD, PhD
Institution(s): Memorial Sloan Kettering Cancer Center

Introduction: Previous population-based studies in salivary gland carcinomas have described a relationship between female gender and superior oncological outcome. The aim of this study was to evaluate the prognostic impact of gender in patients with salivary gland malignancies.  

Materials/methods: After Institutional Review Board approval,we conducted a retrospective chart review of 886 patients that underwent primary surgery for salivary gland carcinoma at Memorial Sloan Kettering Cancer Center between 1985 and 2015. Pediatric patients were excluded. Patient, tumor and treatment characteristics were recorded. Histologies were classified in three risk groups: low, intermediate and high. Survival outcomes were determined using the Kaplan-Meier method. Unadjusted and adjusted hazard ratios for male gender were determined using the Cox proportional hazards model.

Results: Of the 867 patients identified, 52% had minor and 48% major salivary gland cancer.  The most frequent histologies were mucoepidermoid carcinoma (34%), adenoid cystic carcinoma (22%) and carcinoma ex- pleomorphic adenoma (9%).  Female patients were younger (58 versus 60 years; p<0.046) and had significantly lower rates of tobacco consumption (44% versus 64%; p<0.001). Female patients had a lower incidence of high-risk histologies (25% versus 40%, p<0.001) and stage III/IV disease (30% versus 45%, p<0.001).  With a median follow-up of 57 months (range 1-364 months), female patients had a superior 5- and 10-year disease-specific survival (DSS) (5 yr DSS 90% vs 79%; 10 yr DSS 81% vs 65%). The unadjusted hazard ratio showed male patients had a 2.17 fold increased risk of death (HR 2.17; 95% CI, 1.52-3.09, p<0.001).  However, after adjusting for age, histological risk group and overall pathological stage male gender was no longer a significant predictor of poor DSS (HR 1.37;95% CI, 0.95-1.98, p=0.094). Subgroup analysis showed DSS for male and female patients were similar for patients with low risk histology and for intermediate risk histology. However, there was a significant poorer DSS for male patients with high risk histology (HR 1.84; 95% CI, 1.19-2.84, p=0.005). 

Conclusion: Male gender with high risk histology is associated with poorer survival outcome.