Ductal Carcinoma In Situ in Borderline Phyllodes Tumor: A Diagnostic and Treatment Dilemma.

The co-existence of breast carcinoma in the form of ductal carcinoma in situ (DCIS) in a case of Phyllodes tumor (PT) is extremely rare. We present a case of a pre-menopausal lady with a large breast lump diagnosed as benign PT on her initial biopsy. Wide local excision and breast conservation with round block oncoplasty were done. A post-operative diagnosis of borderline PT with sclerosing adenosis and high-grade DCIS were made. Adjuvant radiotherapy and hormonal therapy were given, and the patient had no recurrence after three years of follow-up. DCIS in PT is very rare, and hence no standard protocol for treating such cases exists. So proper histopathological diagnosis, treatment with multidisciplinary involvement, and regular follow-up can help us conserve the breast and prevent recurrence in such cases.