Abstract

Spindle cell carcinoma of the upper aerodigestive tract mucosa was usually presented as polypoid mass and shows squamous cell carcinoma or dysplasia in the surface and underlying spindle cell proliferation. The spindle cell area discloses a variable pattern of sarcoma including rare osteosarcoma of 0~20% incidence. The histogenetic origin of the spindle cell component is now considered a metaplasia of squamous cell carcinoma. We experienced a case of spindle cell carcinoma of larynx showing massive underlying bone formation with proliferation of osteoclast-like cells in 75 year-old man. The immunohistochemical study demonstrates positive reaction with cytokeratin in area of squamous cells and with vimentin in area of spindle cells and osteoclasts. There are very focal reactivity for high molecular weight cytokeratin in spindle cell area.

• Keywords: Spindle cell carcinoma;Larynx;Osteoid;