[A case of local recurrence developing thirty-nine years after mastectomy for breast cancer].

Here we report a case of breast cancer that recurred after a 39-year latency period. A 73-year-old woman,who had undergone radical mastectomy for left breast cancer 39 years previously,consulted our hospital complaining of lymphedema in the left arm. A computed tomography(CT)scan showed a growth of soft tissue in the left chest wall. A core needle biopsy resulted in the pathological diagnosis of metastatic adenocarcinoma,which stained positively for estrogen and progesterone receptors,but not for human epidermal growth factor receptor 2(HER2). Diagnosed with local recurrence of breast cancer, the patient was consequently treated with hormone therapy using anastrozole and achieved a partial response. The patient is currently free from further recurrent disease at 7 months. We report this late recurrence of breast cancer 39 years following mastectomy,suggesting that possible recurrence of this disease with more than a 30-year latency period should be taken into consideration.