A recent study suggests that younger breast cancer survivors with a germline pathogenic variant or those with an initial diagnosis of in situ vs invasive primary breast cancer have a significantly higher risk for a second primary breast cancer.Women who are diagnosed with breast cancer at age 40 or younger are about two to three times more likely to develop second primary breast cancer compared with women who are older when first diagnosed.
To classify the risk of developing a second primary breast cancer, the researchers evaluated a main cohort of 685 patients with stages 0-III breast cancer who were diagnosed at age 40 years or younger and had undergone unilateralas primary surgery between August 2006 and June 2015. The team also analyzed data on 547 younger women who had a bilateral mastectomy.