Cutaneous Metastasis With Squamous Differentiation in Triple-Negative Breast Cancer: A Rare Case of Histologic Transformation With Clinical Implications

Breast cancer is a frequently encountered malignancy in females, with its incidence influenced by a variety of factors. Among its subtypes, triple-negative breast cancer (TNBC) tends to have a more aggressive clinical course and limited treatment options. Cutaneous metastasis with squamous differentiation is an uncommon manifestation typically associated with advanced or recurrent disease. We report the case of a 63-year-old female previously diagnosed and treated for TNBC in Syria, who later presented to our institution with advanced disease. Despite further management efforts, the disease progressed rapidly, and the patient ultimately passed away. This case highlights the aggressive nature of certain breast cancer subtypes and the importance of recognizing atypical metastatic presentations.