Clinicopathological and prognostic exploratory study of primary metaplastic squamous cell carcinoma of the breast

PMSCCB occurs exclusively in females, with a mean age of onset of 53.11 ± 10.83 years, and 46.1% of the patients were premenopausal. It is characterized by high expression of CK5/6, p63, and EGFR, which can aid in diagnosis. There is low expression of ER, PR, and HER-2, which may offer opportunities for targeted and endocrine therapies. Anthracyclines combined with cyclophosphamide or/and taxanes may prove effective in chemotherapy treatment. p16-positive expression does not necessarily indicate high-risk HPV infection, and the expression of p53, p16 and EGFR is not correlated with prognosis. However, distant metastasis and GATA3 expression are significant factors influencing the prognosis of PMSCCB.