Breast hydatid cyst presented as a fluctuant painless lump mimicking galactocele: A case report.

Hydatid disease is a zoonosis caused by the Echinococcus species. The liver and lungs are where it generally seen, with breast involvement being extremely uncommon. This is a case of a woman aged 28 years who presented with a progressive painless swelling on the left breast, which was fluctuant and nontender, detected on the upper outer quadrant. The cytologic evaluation yielded a crystal-clear fluidal aspirate composed of a few laminated metachromatic materials and the mass sonographically appeared as an anechoic cystic mass having a double-layered wall with posterior acoustic enhancement. A radical pericystectomy was performed after the preoperative diagnosis of breast hydatid cyst was entertained, and the diagnosis was later confirmed by histopathology. Although isolated breast hydatid cysts are uncommon, they can happen and may mimic other cystic and solid masses of the breast clinically. Thus, radiologic assessment with cytopathologic correlation is imperative for precise preoperative diagnosis and to minimize the risk of intraoperative complications.