Abstract
Background Chordomas are rare, locally aggressive neoplasms thought to arise from notochordal remnants in the axial skeleton. Primary intradural chordomas are considered to be extremely rare. In this article a giant intradural petroclival chordoma is presented, and a synthesis of the available literature is performed to measure overall survival (OS) and recurrence-free survival (RFS) and to identify prognostic factors. Methods A systematic Medline review yielded 47 patients with purely intradural tumors from 38 publications including 39 chordomas, 8 cases of ecchordosis physaliphora, and 1 case with features of both. The 5-year OS and RFS were calculated based on the Kaplan-Meier method. Risk factors for progression or mortality were analyzed using binomial logistic regression. Results Maximal tumor diameter varied from 1.5 to 6.0 cm (mean: 3.2 cm). Tumors were located predominantly in the prepontine area (66.7%). Combined 5-year Kaplan-Meier OS and RFS were 77% ± 11% and 74% ± 11%, respectively. Incomplete surgical resection, larger tumor diameter, and an elevated Ki-67 index were statistically more frequent in cases of recurrence and mortality. Conclusions Based on a systematic literature review, the behavior of primary intradural chordomas may be closer to typical chordomas than was previously thought.