A case report: Blastic plasmacytoid dendritic cell neoplasm is misdiagnosed as breast infiltrating ductal carcinoma

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic tumor that typically occurs in older adults. Patients with BPDCN usually present with solitary or multiple skin lesions. Localized or disseminated lymphadenopathy at presentation is common. A case report illustrating histopathologically proven BPDCN initially misdiagnosed as breast infiltrating ductal carcinoma in a 39-year-old woman is presented. In this case, the patient presented with a breast mass without an obvious skin lesion initially. The morphology of the tumor cells mimicked high grade breast carcinoma cells. Without complete immunohistochemical study, this case was initially misdiagnosed as infiltrating ductal carcinoma. Reviewing the previous literature about BPDCN, no case with a breast mass and an absence of characteristic skin lesions initially has been reported. The purpose for which we are discussing this case is to reduce misdiagnosis when the initial symptom is unusual.