Disseminated subarachnoid chordoma: long-term favorable follow-up of a pediatric patient

Chordoma of the corpus callosum: case report

Chordomas are neoplasms that typically arise from midline skeletal structures and rarely originate within the intradural compartment of the CNS. A chordoma arising from the corpus callosum has not been previously described. The authors report the surgical management of a chordoma originating within the splenium of the corpus callosum. To determine the incidence and distribution of intracranial intradural chordoma, a literature search for additional cases was performed. MEDLINE was searched using the MeSH keyword "chordoma," yielding 2010 articles. These articles were screened for cases of primary intradural chordoma rostral to the craniocervical junction, which led to the identification of 46 relevant articles. The authors report the case of a 69-year-old man who initially presented with nonspecific neurological symptoms including spatial disorientation and cognitive decline. These symptoms eventually prompted intracranial imaging, including MRI, which revealed a ring-enhancing, heterogeneous, cystic mass localized within the splenium of the corpus callosum and extending into the bilateral ventricles. The lesion was believed to represent a high-grade glioma and the patient underwent a left interhemispheric approach and subtotal resection. After pathologic evaluation confirmed a diagnosis of an anaplastic chordoma, the patient underwent further resection. A gross-total resection (GTR) was achieved with a transfalcine approach to the contralateral portion of the tumor. Postoperatively, the patient had a partial left homonymous quadrantanopsia, but was otherwise at his neurological baseline. Proton beam radiotherapy was performed to the resection cavity but diffuse intraventricular disease ensued. The results of a literature search suggest that a chordoma arising in the corpus callosum has not been previously described. The present case demonstrates that chordomas can occur in the corpus callosum, and illustrates the utility of a transfalcine approach for GTR of lesions in this location, as well as the need for improved strategies to prevent intraventricular dissemination.

Chordoma dedifferentiation after proton beam therapy: a case report and review of the literature

Background

Chordoma is a rare invasive bone tumor that may occur anywhere along the neuraxis. A total of three primary histological varieties have been identified: conventional, chondroid, and dedifferentiated.

Case presentation

We report a case of an 8-year-old white girl who presented with conventional chordoma, was treated with surgical resection and mixed proton and photon beam therapy, and had a recurrence in the resection cavity 2.5 years later with dedifferentiated morphology. The recurrent tumor did not express brachyury, a recently identified protein specific to tissue of notochordal origin.

Conclusions

The short time period between radiation therapy and dedifferentiation, low dose of photons, and rarity of dedifferentiated skull base chordomas in pediatric patients should alert clinicians to the possibility of chordoma dedifferentiation after proton beam therapy.

Giant petroclival primary intradural chordoma: case report and systematic review of the literature

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.