[Usefulness of Breast Ultrasound in Follow-Up of Post-Operative Metachronous Contralateral Breast Cancer-A Case Report].

Mammography is the standard screening toolfor post-operative breast cancer, with annualcheck -ups recommended; however, it misses some cancers. We report a case a metachronous contralateral breast cancer detected by breast ultrasound 8 years and 6 months after operation. A 72-year-old women visited our hospital for follow-up 8 years and 6 months after the operation. She was diagnosed with right breast cancer at 63 years of age and underwent partial mastectomy with axially lymph node dissection. The pathological diagnose was scirrhous carcinoma. After chemotherapy and radiation therapy, she underwent screening with annual examinations. The mammography finding was normal, but an ultrasound showed a mass lesion in the contralateral breast. The pathological diagnosis of the biopsy specimen was mucinous carcinoma. A history of breast cancer is known to suggest an increased risk of metachronous contralateral breast cancer. Therefore, regular follow-up with breast ultrasound, not only mammography, is recommended.