OBJECTIVETo report 2 rare cases of benign notochordal cell tumor (BNCT), according to WHO classification of tumors of soft tissue and bone (4th edition). Their radiologic and clincopathologic features and differential diagnosis were investigated.

METHODSTwo cases of BNCT were studied by retrospective review of the clinical, radiologic, pathologic and immunophenotypical findings. Related literatures were reviewed at the same time.

RESULTSCase 1 was a 53-year-old man, and case 2 was a 61-year-old woman. Radiographically, both patients presented with abnormal imaging findings in the fifth cervical vertebral body with the lesions located within the bone but without extra osseous mass. Histopathologically, the lesions lacked lobular architecture and extracellular myxoid matrix. The tumor cells were vacuolated and had centrally or peripherally placed round or oval nuclei with small nucleoli, mimicking mature adipocytes. No cytological atypia or mitotic figures were seen. The affected bone trabeculae were sclerotic and islands of bone marrow were often entrapped within the tumor.

CONCLUSIONSAlthough sharing similar anatomic distribution and immunophenotype to those of chordoma, BNCT has distinct radiologic and pathologic features and different treatment and prognosis. The differential diagnosis between BNCT and chordoma requires detailed clinical, radiologic and histopathologic evaluations.