A new subtype of papillary ductal carcinoma in situ with tall cell and reversed polarity morphology: a rare case report

We herein present a rare case of papillary ductal carcinoma in situ with tall cell and reversed polarity morphology breast cancer, which can closely mimic tall cell carcinoma with reversed polarity and ductal carcinoma in situ. Thorough evaluations of histologic features, immunohistochemistry results, and genetic alterations are significant in identifying this rare entity. In addition, this type of breast cancer is low-malignant and has a favorable prognosis without any adjuvant therapy after complete resection.