<unk>  accounts for approximately 15–20% of all breast<unk>  cases. The overall proportion of<unk>  is very similar in all age groups. Younger women have a higher rate of basal or BRCA related<unk> , while older women have a higher proportion of apocrine, normal-like and rare subtypes including neuroendocrine<unk> . A study in the US has shown that, among younger women, African American and Hispanic women have a higher risk of<unk> , with African Americans facing worse prognosis than other ethnic groups. One known risk factor for<unk>  is germline mutations. These are alterations within the heritable lineage that is being passed down to the offspring. Due to their high disposition for<unk> s of the breast, ovaries, pancreas, and prostate, the BRCA1 and BRCA2 genes were identified as high risk for<unk><unk> . Changes or mutations in 19p13.1 and MDM4 loci have also been associated with<unk> , but not other forms of breast<unk> . Thus,<unk><unk>  tumors may be distinguished from other breast<unk>  subtypes by a unique pattern of common and rare germline alterations. In 2009, a case-control study of 187<unk>  patients described a 2.5 increased risk for<unk>  in women who used oral contraceptives (OCs) for more than one year, compared to women who used OCs for less than one year or never. The increased risk for<unk>  was 4.2 among women 40 years of age or younger who used OCs for more than one year, while there was no increased risk for women between the ages of 41 and 45. Also, as duration of OC use increased,<unk>  risk increased.
Triple-negative breast cancer
Hereditary lobular breast cancer
Hormone receptor positive breast tumor
Paget's disease of the breast
Mucinous carcinoma of the breast
Medullary breast carcinoma
Inflammatory breast cancer
Hormone-sensitive cancer