Calcification in oligodendroglioma.

Forty-four previously diagnosed surgical biopsy specimens of oligodendroglioma with calcification from the file of Veterans General Hospital-Taipei between 1977-1985 form the base of this study. Thirty-two patients (72.8%) had varied degree of calcification deposits in tumor parenchyma related to blood vessels while 12 patients (27.2%) in tumor parenchyma unrelated to blood vessels. Ten patients (22.7%) disclosed calcification at the vicinity of tumor tissue. Histochemical studies of the calcified deposits revealed no trace minerals other than calcium and iron. Electron microscopic examination of the calculi showed membrane-bound vesicles and radially precipitated crystals that simulated hydroxyapatite of psammoma body in meningioma. There was no statistically significant correlation between the demise or recurrence of patients and the calcification of tumor when Chi-squared test was applied.