Myxoma of the cranial base

In 1871, Virchow described a type of tumor, which he named myxoma, which had a similar appearance to mucinous tissue of the umbilical cord. Myxoma occurs most frequently in the heart and jawbone, less frequently in the temporal bone mastoideum, and rarely in the cranial base of the brain. From an etiologic perspective, intracranial myxoma is divided into either primary or secondary induction. The majority of primary myxomas are found at the skull base, whereas secondary intracranial myxomas are mainly caused by metastatic tumor emboli from the cardiac myxomas; the emboli may also transfer to cerebrovascular endothelium to cause fusiform aneurysm. From October 1983 until November 2005, 23 patients with cranial base myxoma, as confirmed by pathology, were treated in the neurosurgery department of Beijing Tiantan Hospital. Few data are available from published literature on diagnosis and treatment of cranial base myxoma; therefore, the aim of this study was to describe a large series of patients undergoing treatment for cranial base myxoma and to analyze and discuss clinical manifestations, diagnosis, and treatment of cranial base myxoma.

A retrospective analysis was undertaken of 23 cases of cranial base myxoma, as confirmed by pathologic diagnosis. The review included all patients treated between October 1983 and November 2005. Among the 23, 8 patients received adjuvant radiotherapy after surgery. Postsurgical outcome data were unavailable for 12 patients. The mean duration of follow-up in the remaining 11 patients was 64.5 months.

Tumors were commonly located at the middle fossa, parasellar, and jugular regions with characteristic calcification demonstrated with magnetic resonance imaging. Patients presented with headache and multiple lesions of the cranial nerves. Surgical approaches were variable and selected according to tumor locations. Partial resections were achieved in 16 cases and total resections in 7 cases. Complete relief of clinical symptoms was achieved in 2 cases, unchanged in 11 cases, and aggravated in 9 cases. During the period of follow-up, remission was gained in 6 cases and tumor recurrence in 4 patients; 1 patient died.

Cranial base tumors are difficult to diagnose. By clinical features and neuroradiological findings, it is hard to distinguish myxoma from chondroma and chordoma in this region. Treatment results are seldom encouraging; the goal of complete surgical resection is rarely achieved, and the outcome of radiotherapy is not very successful.