Cystic squamous metaplasia in a giant benign phyllodes tumor of the breast: a case report.

Phyllodes tumor is a rare tumor of the breast, which encompasses both stromal and epithelial components. In these components, metaplastic changes can be observed occasionally. We report the case of a 51-year-old woman nulligest menopaused who presented a huge mass, largely ulcerated in her right breast. The radiological examination revealed a large tumor with microcalcifications classified as Breast Imaging and Reporting Data System Category 5. The patient undergone right mastectomy and the histological analysis revealed benign phyllodes tumor with cystic squamous metaplasia. Therefore, we aim to present this uncommon event occasionally occurring in phyllodes tumor of the breast.