Encapsulated Papillary Carcinoma of The Breast: A Case Series

Abstract Introduction: Encapsulated papillary carcinoma (EPC）of the breast is a rare type of breast cancer with excellent prognosis. It is usually considered a variant of ductal carcinoma in situ (DCIS). However, no consensus on EPC treatment and management has been achieved. We provide some data from our clinical centers to help better manage this disease.Methods: We performed a retrospective analysis of patients diagnosed with EPC from March 2015 to December 2019 at The First Affiliated Hospital of Anhui Medical University. Demographic information, tumor details, immunohistochemical markers, clinical data, stage of the disease, treatment modalities, and oncological outcomes were collected.Results: Eleven cases were included in this retrospective study: three cases had pure EPC, six cases had EPC associated with DCIS, and two cases had EPC associated with invasive cancer. Among the patients, two had lymph node metastases. The mean age of female patients at diagnosis was 53.6 years. The one male patient was 48 years old. The mean tumor size was 2.4 cm. Myoepithelial cell layers were completely absent in all cases. Ten patients were estrogen receptor and progesterone receptor positive and human epidermal growth factor receptor-2 negative. Nine patients underwent mastectomy, and two underwent breast-conserving surgery.Conclusion: Adequate local therapy results in excellent prognosis. Radiation therapy should be offered to patients with EPC who undergo breast-conserving surgery. Immunohistochemistry is necessary in diagnosing EPC and excluding other papillary lesions. Excisional biopsy should be performed to achieve comprehensive diagnosis. Sentinel lymph node biopsy is recommended for patients with EPC.