Surgical treatment choices for breast cancer in Newfoundland and Labrador: A retrospective cohort study

Abstract

Background: Mastectomy is often chosen by women for treatment of breast cancer, even when breast-conserving surgery (BCS) is an option. Newfoundland and Labrador has a high mastectomy rate. We documented the number of breast cancers over a given period in the province and their related surgical treatments, and explored the impact of several variables on surgical choice. Methods: A retrospective cohort design linked diagnosis data from the Newfoundland and Labrador tumour registry to surgery data from the Canadian Institute for Health Information Discharge Abstract Database. Data were extracted for all women aged 19 years or more in whom breast cancer was diagnosed in 2009-2014. Results: A total of 2346 cases of breast cancer with a linked surgical procedure were included. Most operations (1605 [68.4%]) were mastectomy procedures, with the remainder being BCS. Logistic regression analysis revealed that women were 1.82 times (95% confidence interval [CI] 1.64-2.02) more likely to have mastectomy for each unit of stage increase from 0 to IV and 1.15 times (95% CI 1.11-1.21) more likely for each unit of driving time increase. Conclusion: Tumour stage and driving time to a radiation facility significantly predicted Newfoundland and Labrador women's surgical treatment choices for breast cancer. Notably, mastectomy was the favoured choice across all age groups, tumour stages and geographical regions of the province. We hope that these results will galvanize efforts to better understand local surgical practices and assist in improving the quality of surgical care of women with breast cancer.