title: Extraosseous benign notochordal cell tumor originating in the lung: a case report.
abstract: Benign notochordal cell tumors (BNCTs) are tumors originating in the axial skeleton, where chordomas occur. Although very rare, some cases of extraosseous chordoma, such as in the soft tissue and lungs, have been reported. We report a case of a primary tumor showing the notochordal characteristics of BNCTs within the axial skeleton.An asymptomatic 57-year-old woman presented with an abnormal shadow on her chest radiograph; chest computed tomography revealed a well-defined round nodule. The resected sample tissue contained a jelly-like small nodule. Histologically, it was identified as a BNCT, based on minimal nuclear atypia, extremely low mitotic activity within the tumor cells lying in a sheet-like arrangement, and focal immunopositivity for brachyury.This is the third case report of BNCT originating in the lungs; BNCTs are considered asymptomatic tumors that are identified by using highly developed chest imaging technology; however, our findings also suggest that these notochordal tumors may potentially originate from extraosseous sites that lack ideal precursor cells. Our case suggests that notochordal tumors can arise from organs that are unrelated to known notochordal development.
authors.affiliation: From the Department of Thoracic Surgery (YT, MH, HH); and Department of Pathology (TM, YF, TH), Tokyo Metropolitan Cancer and Infectious Diseases Center, Komagome Hospital, Bunkyo-ku, Tokyo, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Toru
authors.initials: T
authors.lastname: Motoi
authors.forename: Masahiko
authors.initials: M
authors.lastname: Harada
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Fukuda
authors.forename: Tsunekazu
authors.initials: T
authors.lastname: Hishima
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Horio
mesh_terms: D005260:Female; D006801:Humans; D008168:Lung / Q000473:pathology*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D008875:Middle Aged; D009373:Neoplasms, Germ Cell and Embryonal / Q000000981:diagnostic imaging / Q000473:pathology*; D011859:Radiography