Breast cancer is the most common of all cancers in women in both developed and developing countries. Worldwide incidence has increased by more than 20 percent since 2008; and in India this rate of increase is 27 percent (in 2012), overtaking that of cervical cancer. It is evidenced that the sex hormones and, therefore, the genes involved in the development mammary glands are also responsible for differential development of the 2nd and the 4th digit of the hands, in early fetal life. Hence, a relationship between the ratio, 2D:4D and breast cancer has been speculated. In the case of any positive relationship, the 2D:4D ratio in early life can be taken as a proxy-indicator for the risk of breast cancer in later life.

Many studies around the world, including one in India, established an association between 2D:4D and Breast cancer. The present study had been conducted on a sample of Breast cancer patients, with a control of nearly equal number, among Bengali Hindu population of West Bengal, India. The analysis does not indicate any relationship between 2D:4D and breast cancer.