A highly aggressive invasive ductal carcinoma from a complex cystic breast mass and BI-RADS assessment: A case report

RATIONALE: The term cystic breast lesions is a sonographic diagnosis, which can be categorized as simple, complicated or complex. The complex cysts are deemed as having a low risk of breast cancer. The highly aggressive invasive ductal carcinomas among complex cysts, in particular, are infrequent reported. PATIENT CONCERNS: A 56-year-old female with a breast complex cyst who, after fine-needle aspiration, complained about oozing with fluid as well as skin ulceration that did not heal. DIAGNOSES: An advanced HER-2-enriched invasive ductal carcinoma was diagnosed. INTERVENTIONS: The patient received neoadjuvant chemotherapy of anti-HER-2 target drug, palliative surgery and following postoperative chemotherapy. OUTCOMES: The patient was in good general condition at 6 months follow-up after surgery. LESSONS: Meticulous ultrasound evaluation of Breast Imaging Reporting and Data System (BI-RADS) category is crucial and indispensable when a complex cyst is found. The radiologist and clinician should be fully awake to its possibility of malignancy, especially fast-growing one in post-menopausal women. Excision biopsy may be preferred for diagnosis.