Abstract

Purpose

Breast cancer is a multi-factorial disease with marked geographical and ethnic variation in epidemiology and risk factors. However most of the literature that defines screening and management guidelines of breast cancer is derived from large prospective trials on western population, the applicability of which to other ethnic groups with possibly different disease biology is questionable. The purpose of this study is to analyze the applicability of the Gail model to Indian females.

Methods

The case records of 688 patients, ≥40 years old diagnosed at our institute with invasive breast cancer in 2012-2013 were retrospectively analyzed. Breast cancer risk estimates of these patients in the 5-year period prior to their diagnosis were calculated using the Breast Cancer Risk Assessment Tool (BCRAT).

Results

The median estimated 5-year risk using BCRAT was 0.7%. Since all these patients were diagnosed in 2012-2013, a significant proportion (at least 95%, assuming significance at p < 0.05) of them were supposed to be in the high-risk group in the 5- year period prior to their diagnosis. However, only 2.9% of the studied population was in the high-risk group as calculated using the BCRAT (p < 0.0001). Even after

including the other factors defined by the NCCN that categorize the patients as high risk, only 4.1 % of the population fell into this group.

Conclusion

Gail model does not accurately predict the risk of breast cancer in Indian females. This study highlights the need for development of independent databases for each ethnic group rather than universally adopting protocols designed from western databases.