Squamous cell carcinoma, spindle cell

Rare, aggressively growing squamous cell carcinoma of the skin characterized by a high propensity to metastasize.

The tumour clinically impresses with a fast-growing, mostly ulcerated, red or skin-coloured lump.

Histologically, the tumor is characterized by spindle-cell, undifferentiated, cytokeratin positive, eosinophilic epithelial formations embedded in a connective tissue stream. Evidence of numerous nuclear polymorphisms and mitoses. Occasionally also multinuclear epithelial giant cells. Differentiations with formation of horny beads are mostly missing.

The most important histological differential diagnosis is the atypical fibroxanthoma (AFX).

Excision with a sufficient safety distance to all sides.

1. Defty CL et al(2011) Basaloid squamous cell carcinoma with 'monster' cells: a mimic of pleomorphic basal cell carcinoma. J Cutan catheter 38:354-356.
2. Ellis R et al(2015) Pleomorphic spindle cell dermal neoplasm with dot-like keratin reactivity: keratin-positive AFX or carcinoma? J Cutan catheter 42:847-852.
3. Kanner WA et al(2010) CD10, p63 and CD99 expression in the differential diagnosis of atypical fibroxanthoma, spindle cell squamous cell carcinoma and desmoplastic melanoma. J Cutan pathogen 37:744-750.
4. Lagana SM et al(2011) Pleomorphic (spindle and squamous cell) carcinoma arising in a peripheral mixed squamous and glandular papilloma in a 70-year-old man. Arch Pathol Lab Med 135:1353-1356.