Comparison between Early and Late Onset Breast Cancer in Pakistani Women Undergoing Breast Conservative Therapy: is There any Difference?

Background: Early onset breast cancer is associated with poor outcomes but variable results have been reported. It is a significant problem in Pakistani women but remains under reported. Breast conservation plays an important role in surgical management of this younger patient group. The objective of this study was to determine the outcome of breast conservative therapy in patients with early onset breast cancer in our population and compare it with their older counterparts. Materials and Methods: A review of patients with invasive breast cancer who underwent breast conservation surgery at Shaukat Khanum Cancer Hospital from 1997 to 2009 was performed. Patients were divided into two groups i.e. Group I age <= 40 and Group II >40 years. A total of 401 patients with breast cancer were identified in Group I and 405 patients in Group II. Demographics, histopathological findings and receptor status of the two groups were compared. The Chi square test was used for categorical variables. Outcome was assessed on basis of 10 year locoregional recurrence free survival (LRRFS), disease free survival (DFS) and overall survival (OS). For survival analysis Kaplan Meier curves were used and significance was determined using the Log rank test. Cox regression was applied for multivariate analysis. Results: Median follow up was 4.31 (0.1-15.5) years. Median age at presentation was 34.6 years (17-40) and 51.9 years (41-82) for the two groups. Groups were significantly different from each other with respect to grade, receptor status, tumor stage and use of neoadjuvant therapy. No significant difference was present between the two groups for estimated 10 year LRRFS (86% vs 95%) (p=0.1), DFS (70% vs 70%) (p=0.5) and OS (75% vs 63%) (p=0.1). On multivariate analysis, tumor stage was an independent predictor of LRRFS, DFS and OS. Conclusions: Early onset breast cancer is associated with a distinct biology but does not lead to poorer outcomes in our population.