WASHINGTON, Jan. 13 (Xinhua) -- The U.S. Food and Drug Administration (FDA) has expanded the approved use of a drug to treat certain types of breast cancer that have spread and whose tumors have a specific inherited genetic mutation.

It is the first time any drug has been approved to treat certain patients with metastatic breast cancer who have a "BRCA" gene mutation, the FDA said on Friday.

Patients are selected for treatment with Lynparza based on an FDA-approved genetic test.

"This class of drugs has been used to treat advanced, BRCA-mutated ovarian cancer and has now shown efficacy in treating certain types of BRCA-mutated breast cancer," said Richard Pazdur, director of the FDA's Oncology Center of Excellence. "This approval demonstrates the current paradigm of developing drugs that target the underlying genetic causes of a cancer, often across cancer types."

Breast cancer is the most common form of cancer in the United States. It is estimated that approximately 252,710 women will be diagnosed with breast cancer this year, and 40,610 will die of the disease, according to the FDA.

It says about 20 to 25 percent of patients with hereditary breast cancers and 5 to 10 percent of patients with any type of breast cancer have a BRCA mutation.

BRCA genes are involved with repairing damaged DNA and normally work to prevent tumor development. However, mutations of these genes may lead to certain cancers, including breast cancers. Lynparza helps block an enzyme involved in repairing damaged DNA.

By blocking this enzyme, DNA inside the cancer cells with damaged BRCA genes may be less likely to be repaired, leading to cell death and possibly a slow-down or stoppage of tumor growth.

Lynparza was first approved by the FDA in 2014 to treat certain patients with ovarian cancer and is now indicated for the treatment of patients with breast cancer.