Pregnancy-associated breast cancer and increased risk of pregnancy-associated recurrence: a case report

Pregnancy-associated breast cancer refers to breast cancer diagnosed during pregnancy, lactation, or within twelve months postpartum. Recent studies suggest that, when matched for age and stage, the prognosis of pregnancy-associated breast cancer is comparable to non-pregnancy-associated breast cancer. However, the risk for breast cancer recurrence associated with subsequent pregnancies in this population is not clear.

We describe the case of a Caucasian woman who was initially treated for pregnancy-associated breast cancer at age 23, three months after the birth of her third child. She underwent a total mastectomy with axillary node dissection, followed by chemotherapy and hormonal therapy. Ten years later, when the patient was 24 weeks pregnant with her fourth child, she presented with an ipsilateral chest wall recurrence of breast cancer. To the best of our knowledge, this represents the first reported case of a pregnancy-associated recurrence in a patient previously treated for pregnancy-associated breast cancer.

The case described here is the first report of a second occurrence of pregnancy-associated breast cancer. This case raises the possibility that pregnancy may represent a unique trigger for breast malignancy in a specific cohort of women. Although there is data showing no increase in the risk of recurrence for women who become pregnant after breast cancer treatment, pregnancy-associated breast cancer may be a distinct clinical category where subsequent pregnancies after treatment may confer an increased risk of recurrent disease.