Primary falcine chondrosarcoma

Primary extraosseous dural chondrosarcoma: a case report

BACKGROUND

Dural chondrosarcoma is a very rare intracranial tumor, given that meninges do not normally contain cartilaginous tissue from which it can originate. We present a case of primary extraosseous dural chondrosarcoma.

CASE PRESENTATION

A 48-year-old woman presented to our tertiary center neurosurgery consultation with progressive headache, vomiting, vertigo, and gait instability of 5 months' duration. An initial brain CT revealed a large parietal mass with gross calcifications and subtle hyperostosis of the inner table. Subsequent brain MRI showed a heterogeneous expansive lesion with a honey-comb enhancement. Discussion of intra- or extra-axial location was warranted, and finally, initial presurgical suspicion of meningioma arose although some atypical imaging features were detected. The differential diagnosis included solitary fibrous tumor-hemangiopericytoma and dural metastasis. Total resection of the lesion was performed, extra-axial origin was confirmed, and pathology resulted in a primary dural chondrosarcoma.

CONCLUSION

The importance of this case presentation lies in the unusual nature of the final diagnosis, the brief literature review and differential diagnosis with emphasis on imaging pearls, as well as the useful reminder for physicians to consider less frequent diseases when key findings do not unambiguously lead to the usual suspects.

Intracranial Nonskull-Based Chondrosarcoma Arising from the Sagittal Sinus: A Case Report and Review of the Literature

BACKGROUND

Intracranial nonskull-based chondrosarcoma is a very rare malignant tumor. In fact, it is difficult to diagnose because of its atypical radiologic and morphologic features. We report a case of an intracranial parasagittal chondrosarcoma in the left parietal lobe accompanied with significant peritumoral edema (an extremely rare phenomenon for this tumor), with a review of the literature, to clarify aspects in the diagnosis of this rare tumor.

METHODS

A literature search was using PubMed with specific key terms, inclusion criteria, and exclusion criteria. Selected case studies and case series were then compared and summarized them in Table 1. A 59-year-old male patient presented with a history of progressive right hemiparesis and loss of sensation for 45 days.

RESULTS

Magnetic resonance imaging revealed a 2.6 × 2.4 × 2.8-cm mass arising from the superior sagittal sinus in his left parietal lobe. A left parietal parasagittal craniotomy was performed, and a macroscopically complete excision of the tumor was achieved. The patient recovered well postoperatively. Regular follow-up after 6 months revealed that he had almost recovered full strength to his right limbs, and there was no evidence of recurrence. Intracranial parasagittal chondrosarcoma in the parietal lobe is extremely rare.

CONCLUSIONS

Although magnetic resonance imaging was performed, it is sometimes difficult to distinguish intracranial chondrosarcoma from meningioma and glioma, especially when the tumor arises from a nonskull base such as the meninges. Some cases could have significant peritumoral edema, although it is extremely rare. Histologic examination may aid in the diagnosis of this tumor. Neurosurgery is the most effective therapy for these tumors. Postoperative radiotherapy needs to be considered when the tumor is incompletely resected, has atypical histology, or is associated with significant peritumoral edema.

Distinguishing Falcine Chondrosarcomas from Their Mimics and Management

BACKGROUND

Primary intracranial chondrosarcoma is an extremely rare malignant tumor of the central nervous system, which accounts for <0.16% of all primary intracranial tumors. This rare tumor has a high associated morbidity from the tumor itself as well as from treatment modalities.

CASE DESCRIPTION

A 33-year-old man presented with a diffuse headache of 3 months' duration. He was admitted to our department with weakness in the right extremities that had persisted for more than a month. Findings of the neurologic examination revealed right hemiparesis. Cranial magnetic resonance imaging demonstrated a well-demarcated, parasagittal left frontal mass, which compressed to the lateral ventricle. It was hypointense on T1-weighted and hyperintense on T2-weighted images without creating edema in the surrounding tissue. A left frontoparietal craniotomy with complete excision of the mass was performed. The postoperative period was uneventful, and patient was discharged on the fourth postoperative day without any neurologic deficit. Histopathology showed a morphology that was in favor of chondrosarcoma grade 1.

CONCLUSIONS

Dural chondrosarcoma is a possible entity in the differential diagnosis of a presumed meningioma, particularly when atypical features are present. We report a grade 1 intracranial chondrosarcoma of the classical subtype without any neurologic problems after complete surgical excision. The patient did not receive any adjuvant therapy and at 26 months' follow-up showed no recurrence.

Falcine and parasagittal chondrosarcomas

Intracranial chondrosarcomas are primary cartilaginous neoplasms that represent 6% of all skull base tumors. Intracranial extraskeletal chondrosarcomas are more rare, often arising from the meninges at the falx, tentorium, or cerebral convexity. They are generally characterized as classical or mesenchymal, with the latter associated with worse outcomes. We present our institutional series of falcine and parasagittal chondrosarcomas along with a review of the literature. Although skull base chondrosarcomas pose significant challenges due to their invasive biology and proximity to vital brainstem structures and cranial nerves, intracranial extraskeletal chondrosarcomas are generally associated with a good prognosis. Our review of the literature identified 29 patients with falcine and parasagittal chondrosarcomas. There were six recurrences, five among patients with the mesenchymal subtype and one in a patient with the classical subtype. All deaths occurred in patients with the mesenchymal subtype. Management of skull base chondrosarcomas is controversial but extraskeletal intracranial tumors can generally be managed by surgical resection alone. Treatment should be tailored to the biology of the tumor, with radiation therapy reserved for patients with the mesenchymal subtype.

18-year-old woman with a dural mass

We report a case of a dural-based chondroma in the right frontal extra-axial region. Chondromas are benign cartilaginous tumors which are uncommon intracranially. Their diagnosis should be predicated on the exclusion of a chondrosarcoma and clinical studies should be performed to rule out any underlying tumor predisposition syndromes.

Osteochondroma of the convexity: pathologic-neuroimaging correlates of a lesion that mimics high-grade meningioma

Intracranial chondromas are uncommon benign lesions usually attached to dura and located over the convexity of the skull. Osteochondromas are even rarer and additionally contain a benign bony component. Both lesions are reportedly difficult to distinguish from meningiomas on pre-operative neuroimaging studies, although few detailed pathologic-neuroimaging correlation studies have appeared in the literature, particularly for intracranial osteochondromas. A 33-year-old woman with a 4-year history of headaches presented with recent onset of left-sided muscle spasms and weakness. Two days prior to admission to our hospital, neuroimaging studies had shown a large right convexity mass with unusual multifocal bright signal intensities throughout an otherwise isointense mass. The bright signals were interpreted as showing multifocal hemorrhage and the mass was felt to be a convexity meningioma. However, subsequent catheter angiography characterized the lesion as being avascular. The mass was resected en bloc. Extensive histological sectioning revealed a benign osteochondroma predominantly composed of lobules of hypocellular cartilage. Microdissection of the different components revealed that the multifocal, spicule-like bright foci interpreted as hemorrhage on neuroimaging studies were instead foci of benign bone containing metaplastic bone marrow with trilineage hematopoietic cell populations and adipose tissue. Centrally, the hilum of the lesion contained avascular loose connective tissue. No recent or remote hemorrhage was identified anywhere in the lesion. Rare convexity osteochondromas may be mistaken for high-grade meningiomas on neuroimaging studies; their avascular nature, coupled with their complex signal pattern can serve as clues to the correct pre-operative diagnosis.