HER2 positive primary breast squamous cell carcinoma with good prognosis: a case report

The diagnosis of PBSCC relies on histomorphology, due to non-specific imaging manifestations. Immunohistochemical (IHC) staining helps to clarify the pathological type, hormone receptor status, HER2 amplification and programmed cell death ligand 1 (PD-L1) expression, which is essential for clinical decision-making. HER2-positive PBSCC patients can benefit from AC-TH chemotherapy and 1-year anti-HER2 therapy is necessary to good prognosis. If possible, dual anti-HER2 therapy combined with trastuzumab and pertuzumab is recommended. Finally, positive clinical prognosis of PBSCC may be attributed to early detection, immediate surgery, precise diagnosis and proper adjuvant treatment strategy.