Breast cancer diagnosed during pregnancy or 12 months postpartum is referred to as pregnancy associated breast cancer and is reported in 1/3000 pregnancies. Delayed diagnosis is a major issue of pregnancy associated breast cancer. Lactating adenomas are the most prevalent breast masses seen in pregnant women. Although they are not thought to carry an increased risk of cancer, Hertel et al reported the case of a patient who developed invasive ductal adenocarcinoma in the previous excision site of a lactating adenoma. Geschicker and Lewis reported a lactating adenoma containing an associated infiltrating carcinoma and A Saglam et al reported the case of a lactating woman with coexistent lactating adenoma and invasive ductal adenocarcinoma. We report the same case of a lactating woman with lactating adenoma and invasive ductal adenocarcinoma as components of the same mass.

Keyword: Coexistence; Invasive Ductal Adenocarcinoma; Lactating Adenoma.