Abstract 84P
Background
Salivary gland–like tumors represent 2% of primary breast carcinomas. They are histologically triple negative (-ve for ER, PR, and HER2). Salivary and mammary gland tumors show morphological similarities, and it is evident the same neoplasms can arise at both sites but differ in the incidence and clinical behavior according to the primary site. There are numerous studies describing salivary gland tumors but few studies have described this rare subtype of the breast. So the aim of this study was to describe the clinicopathological features of salivary gland tumor of the breast and chemotherapy as a treatment modality.
Methods
We used Surveillance, Epidemiology and End Results (SEER) software to extract the data of 808 patients diagnosed with microscopically confirmed salivary gland tumor of the breast from 2000-2019. We divided them into two subgroups according to the chemotherapy received. We extracted the demographic and clinicopathologic data including: age, race, year of diagnosis, stage, grade, histological subtypes and surgery. We used SPSS version 23 for data analysis. Kaplan-Meier curve, Log-rank test for survival analysis.
Results
Age-standardized relative 5-year survival was 97.1% and cause-specific 5-year survival was 93.5%. The group who had no chemotherapy had survival benefit of only 11% compared to those who received chemotherapy (98.0% and 87.0%, respectively; P=0.24). Performing COX-regression model, age, stage, grade and surgical management were associated with survival outcome (P>0.05) while histological subtypes, year of diagnosis, race and chemotherapy showed no statistical significance (P<0.05).
Conclusions
Salivary gland tumor of the breast has good overall survival. Chemotherapy is the gold standard for triple-negative breast cancer, either primary or combined regimens. However, there was no significant improvement in survival for salivary gland tumor of the breast. These results discourage the use of chemotherapy in this subtype to avoid unnecessary complications.
Legal entity responsible for the study
The author.
Funding
Has not received any funding.
Disclosure
The author has declared no conflicts of interest.