Abstract:
Background: Breast cancer continues to be a major cause of morbidity among women in Sri Lanka. Possible
effects of etiological risk factors on breast cancer specific survival (BCSS) of the disease is not clear.This study was
designed to explore the impact of breast cancer risk factors on the BCSS of patients in Southern Sri Lanka. Method:
This retro-prospective study included all breast cancer patients who had sought immunohistochemistry services at
our unit from May 2006 to December 2012. A pre-tested, interviewer-administered questionnaire was used to gather
information on risk factors. BCSS was estimated using the Kaplan-Meier model. Univariate Cox-regression analysis
was performed with 95% confidence intervals using the SPSS statistical package. Results: A total of 944 breast cancer
patients were included. Five year BCSS was 78.8%. There was a statistically significant difference between the patients
who had a family history of breast cancer and no family history of any cancer in terms of the presence/absence of lymph
node metastasis (p=0.011) and pathological stage (p=0.042). The majority of the premenopausal patients had associated
DCIS (p<0.001) and large tumours (p=0.015) with positive lymph nodes (p=0.016). There was no statistically significant
association between hormone receptor subtypes and hormone related risk factors. Univariate analysis revealed that
breast cancer risk factors had no significant effect on the BCSS. Conclusion: Even though family history of breast
cancer and premenopausal status are associated with poor prognostic features, they, in line with the other breast cancer
risk factors, appear to have no significant effect on the BCSS of patients in Southern Sri Lanka.