Cutaneous carcinosarcoma (metaplastic carcinoma, carcinoma with heterologous differentiation)

Clinical features

•Exceedingly rare

•May arise in the elderly in a pre-existent SCC or BCC   (M>F mean age 72), relatively good prognosis

•May develop in a spiradenocarcinoma, malignant proliferating pilar tumor, matricial carcinoma, carcinoma ex chondroid syringoma or porocarcinoma (M=F, mean age 58 years), generally poor prognosis

Histological features

•Osteoid

•Chondroid

•Smooth muscle

•MFH-like features with osteoclasts

•Neural differentiation