A Population Description of Young Women with Breast Cancer in Newfoundland and Labrador.

It has been well established in the literature that young women tend to carry more aggressive subtypes of breast cancer than their older-aged counterparts. The objective of this study was to describe the characteristics and outcomes of young women with breast cancer. In this retrospective analysis, data were collected for women under the age of 40 years who were diagnosed with breast cancer between 2008 and 2018 in the province of Newfoundland and Labrador. Specifically, data were collected on demographics, staging, pathological characteristics, treatment, and survival outcomes for young women with this disease. Results demonstrate that most of these women were diagnosed between the age of 35 and 39 years (91.2%). Most women presented with early-stage disease (stage I and II-66.4%), while 24% were stage III and 9.6% presented with stage IV metastatic disease. The prevalence of hormone-receptor-positive disease represented 41.9% of the cohort, with triple-negative and HER2+ measuring 27.7% and 30.4%, respectively. Five-year disease-free survival was 80.5% and overall survival was 82.7%. These findings provoke discussion regarding the intersecting roles of genetics, environment, and lifestyle in a region with some of the highest rates of malignancy in the country.