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Raymond Sawaya and Robert Highsmith

✓ Fresh human brain-tumor samples were assayed for their plasminogen activator (PA) content. Specific molecular weight patterns were identified for each of five common brain tumors and for normal brain, suggesting a cell-specific origin of the various PA forms. Malignant tumors contained higher PA activity and a larger number of molecular weight patterns than benign tumors, with the exception of acoustic neurinomas. Irradiated tumors contained lower PA activity than nonirradiated tumors. Finally, a slight but definite correlation between brain edema and PA activity was detected. The future role of brain-tumor PA's for diagnostic and therapeutic purposes is discussed.

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Dandy-Walker syndrome

Clinical analysis of 23 cases

Raymond Sawaya and Robert L. McLaurin

✓ A clinical analysis of 23 patients with Dandy-Walker malformation indicates that more than 85% of them were diagnosed at or before 1 year of age, and that the incidence of associated anomalies is approximately 50%, with a 17% incidence for agenesis of the corpus callosum. The significance of the presence of these anomalies is substantiated by the fact that of the seven deaths recorded, six were related to this disease and five were affected by associated anomalies. The high mortality rate (26%) is comparable to that of other series. The differential diagnosis with posterior fossa extra-axial cysts is discussed.

Ten patients were primarily treated with excision of the cyst membrane; all of them required subsequent shunting to control the intracranial pressure, demonstrating the futility of this approach. None of the patients treated with lateral ventricle shunting suffered an upward herniation of the posterior fossa contents, suggesting that combined shunting of the lateral and fourth ventricles is rarely necessary. The technical advantages of posterior fossa shunting alone are outlined. Of the 16 survivors, 14 were assessed for their mental development by means of standard psychometric testing. The results of the intelligence quotient (IQ) scoring have indicated that 71% of the patients have subnormal mental development (IQ < 83). There was no significant relationship between retardation and associated anomalies, although agenesis of the corpus callosum was related to poor intellectual development in the two patients so affected (IQ's of 50 and 73).

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Raymond Sawaya, Mario Zuccarello and Robert Highsmith

✓ This study was undertaken to confirm the presence of alpha-1-antitrypsin (α 1-AT) in human brain tumors and to attempt to elucidate its significance. Seventy-seven consecutive unselected patients with various brain tumors were entered in this study. The α 1-AT and α 2-macroglobulin contents of the tumor extracts were qualitatively assessed by Ouchterlony immunodiffusion techniques. Plasminogen activator (PA) activity was assayed electrophoretically on sodium dodecyl sulfate gels. The patients were divided into two groups according to the positivity of their tumors to α 1-AT. Sixty-eight percent of the tumors were positive for α 1-AT, and all specimens were negative for α 2-macroglobulin. Clinical and biological parameters obtained in all study patients failed to show statistically significant differences between the two groups with the exception of PA activity (p = 0.001), the peritumoral edema as seen on computerized tomography, and the preoperative serum fibrinogen level. These three parameters were higher in the group with specimens positive to α 1-AT.

This study supports the hypothesis that α 1-AT is produced primarily by tumor cells in proportion to the regional proteolytic and inflammatory activity, and may protect the tumor cells.

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Ajay K. Bindal, Rajesh K. Bindal, Harry van Loveren and Raymond Sawaya

✓ The authors report on a study of eight cases of intracranial plasmacytoma to identify the risk of progression to multiple myeloma and suggest the treatment required for cure of solitary lesions. The diagnosis of multiple myeloma or myelomatous changes was made in the immediate postoperative period in four patients (50%), two of whom had skull base lesions. Of the four remaining patients, three were treated with complete surgical resection and radiation therapy and had no recurrence of plasmacytoma or progression to multiple myeloma during mean follow up of 12 years (range 2–25 years); one patient underwent subtotal surgical resection and had recurrence of the tumor despite radiation therapy.

It is concluded that multiple myeloma is unlikely to develop during the long term in patients with intracranial plasmacytoma who do not develop multiple myeloma or myelomatous changes in the early postoperative period. However, lesions that infiltrate the skull base are not likely to be solitary, and patients who harbor these neoplasms should undergo complete evaluation and close follow-up review to exclude multiple myeloma. A recurrence of solitary intracranial plasmacytoma is possible with subtotal surgical resection despite radiation therapy. Definitive treatment should consist of complete surgical resection with adjuvant radiation therapy.

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Editorial

Neurosurgical “pearls” and neurosurgical evidence

E. Antonio Chiocca