Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Spindle cell carcinoma is a type of cancer that begins in the skin or in tissues that line or cover internal organs and that contains long spindle-shaped cells. Also called sarcomatoid carcinoma. Sarcomatoid carcinoma is a relatively uncommon form of cancer whose malignant cells have histological, cytological, and/or molecular properties of both epithelial tumors ("carcinoma") and mesenchymal tumors ("sarcoma").