Benign notochordal cell tumor

Abstract

Benign notochordal tumor is a benign indolent bone tumor probably derived from vestigial notochordal rests. As it is usually asymptomatic, its true incidence is unknown but has been found in 20 % of spines in an autopsy study. Radiographs, CT, or bone scan may appear normal. MRI shows altered signal intensity. Histologically, it appears as sheet-like proliferation of bland-looking cells with well-defi ned boundary, resembling fatty marrow at low magnifi cation. Foci of chordoma may be found next to the lesion, suggesting histogenetic relationship. It is immunohistochemically positive for S100, epithelial markers, and brachyury. Surgery is only indicated in large lesions and for differential diagnosis.