Case report: Carcinoma en cuirasse—widespread cutaneous metastases from breast adenocarcinoma

Breast cancer cutaneous metastasis, although rare, requires high vigilance, especially in the HER2-negative Luminal B subtype. The efficacy data on CDK4/6 inhibitors combined with endocrine therapy as a standard regimen for cutaneous metastasis is still lacking. It is necessary to enhance mechanistic studies and clinical observations, taking molecular characteristics into account.