Breast Cancer with Spontaneous Healing of Intraductal Component to which Evaluation of Cancer Extension was Difficult—A Case Report—

Abstract

Partial spontaneous regression, or “healing”, of intraductal component of breast cancer has sometimes been reported, but there are few reports on its clinical implication. We experienced a patient with invasive breast cancer with a “healed” area, and evaluation of cancer extension was difficult. A 64-year-old woman presented to our hospital with category 4 calcification that was pointed out by a breast medical check-up. Because our first biopsy did not reveal malignancy and following mammography showed a temporal decrease in area of calcification, she was followed up. Two years later, re-extension of the calcification nest was seen. The second biopsy revealed ductal carcinoma, so left partial mastectomy with sentinel lymph node biopsy was performed. The resected tumor was HER2-positive, 7mm-sized, invasive ductal carcinoma with extensive intraductal component, with viable and healed components mixed together. Because parts of the viable and healed components were close to the margin of resection, we performed additional total mastectomy. There was no malignancy in the additionally resected specimen. Histological evaluation of both viable and healed intraductal components was considered to be useful for decision of surgical resection area.