Surgical treatment of intracystic carcinoma of the breast

BACKGROUND: Intracystic carcinoma of the breast is a type of breast cancer with favorable prognosis where cancer arises from the cystic wall. However, it is a relatively rare disease, and no general consensus has been reached on its definition, including pathogenesis, extramural invasion, and lymph node metastasis. METHODS: Six patients who underwent surgery at the Department of Surgery at Asahikawa Medical University are presented. In each patient, background factors, diagnosis, surgery, pathological diagnosis, and prognosis were investigated. RESULTS: Fine needle aspiration showed class V disease in three patients and class III disease in the other three, and lumpectomy was performed for class III patients. Three patients underwent breast-conserving surgery While extramural invasion was seen in three patients, lymph node metastasis was absent in all patients. CONCLUSION: When it is difficult to diagnose intracystic carcinoma of the breast by fine needle aspiration, active lumpectomy is necessary. Because extramural invasion and lymph node metastasis have been reported, it is necessary to carefully determine the range of excision and rationally perform lymph node dissection, such as sentinel node biopsy.