Encapsulated papillary carcinoma of the Breast: A Case Report and Literature review

Encapsulated papillary carcinoma (EPC) of the breast is an uncommon variant of papillary neoplasm, constituting approximately 0.5–2% of all breast cancers (1). This carcinoma is histologically distinct, marked by a prominent fibrous capsule encasing a densely cellular structure supported by fibrovascular stalks. A notable feature is the absence of myoepithelial cells within this thick capsule, and EPC is most frequently observed in postmenopausal women, typically between the ages of 55 and 67 (2,3). Clinically and radiologically, EPC often mimics a benign mass. On mammography, it typically appears as a well-circumscribed lesion located in the retroareolar region, whereas ultrasound commonly reveals a cystic mass with solid components. Although usually asymptomatic, the lesion may be detected through self-examination or screening mammography, and a bloody nipple discharge is a commonly reported symptom. Given its generally indolent behavior, EPC is often managed as an in-situ disease. Nevertheless, rare cases of high-grade EPC exhibiting aggressive histological and clinical features have been documented. Overall, EPC is considered a low-risk cancer, with an approximate 5% risk of local recurrence and a generally favorable prognosis (4). We report the case of a 72-year-old woman who presented with two masses in her left breast. An echo mammogram was performed followed by a biopsy, which confirmed the diagnosis of encapsulated carcinoma in the left breast. The patient subsequently underwent a wide double lumpectomy of both lesions, with pathology confirming a diagnosis of non-invasive EPC. This was followed by radiotherapy and adjuvant hormonal therapy.