Could brain tumor be hereditary trait?

Dear Dr. Roach: My cousin was in his mid-40s when he died of a brain tumor. After having similar symptoms, my other cousin, his older sister, who is in her mid-60s, just had surgery to remove a cancerous brain tumor. Is it possible this could be hereditary? Neither of them had any kids, but they have an older brother. Should he get tested? — J.A.M.

Dear J.A.M.: Many cancers run in families. Primary brain cancers are uncommon, and there are different types. A primary brain cancer is one that starts in the brain, as opposed to when cancer in a different area of the body spreads to the brain. Many cancers that can metastasize to the brain run in families.

Two of the more common types of primary brain cancers are astrocytomas and glioblastomas. A review found there is a familial component to astrocytomas but not to glioblastomas. People with a family history of astrocytomas are four times more likely to develop one; however, it would still be unusual even with a family history.

The biggest risk is ionizing radiation, such as a person would get from radiation treatment. However, back in the 1950s, radiation was used to treat skin infections on the head, which has led to an increased risk of brain cancer.

There are some unusual genetic conditions that increase risk for brain tumors, including neurofibromatosis type 2 and multiple endocrine neoplasia type 1.

Since the likelihood of developing a brain tumor is small, I don’t think I would advise screening for their brother. I did look for any studies that might be ongoing to test whether there might be a benefit to screening; unfortunately, I did not find any at clinicaltrials.gov.