[A case of bilateral multiple primary breast cancer].

A 55-year-old woman underwent segmental resection and sentinel lymph node biopsy for cancer in her left breast 2.5 years ago. The pathological findings indicated papillotubular carcinoma [estrogen receptor-positive (ER+), progesterone receptor-positive(PgR+), and human epidermal growth factor receptor 2(HER2) score 0]. After the operation, she received adjuvant radiotherapy and endocrine therapy. Two and a half years after the operation, mammography revealed amorphous calcifications in her right breast. Stereotactic directional vacuum-assisted core-needle biopsy of the calcifications led to a diagnosis of invasive ductal carcinoma (ER+, PgR+, HER2 score 0). We performed quadrantectomy and sentinel lymph node biopsy. After the second operation, she received adjuvant radiotherapy and endocrine therapy with different modalities than used previously. Since the second operation, there has been no metastasis or recurrence.