Are breast cancer and leukemia hereditary?

Some : Some cases of breast cancer genetic mutations brca i and ii , her 2 some breast cancer run in families. In leukemias not enough proof of genetic mutations as in breast cancer ( I do not know ) how ever leukemias run in family members, especially cll and AML , may not be genetic, could be environmental.

Sometimes: Most breast cancers and most leukemias are not hereditary but there are hereditary types of both. Families that have breast cancer, leukemia, and sarcomas may have a rare genetic abnormality called li fraumeni syndrome. If you are concerned seek out a genetic counselor or high risk breast specialist.