✓ Changes in normal rat brain were studied acutely, and at 3, 6, 9, and 12 months following interstitial brachytherapy with high-activity 125I seeds. An 80-Gy radiation dose was administered to an area with a 5.5-mm radius. Effects were measured with magnetic resonance (MR) imaging (with and without gadolinium enhancement), leakage of horseradish peroxidase(HRP), electron microscopy, and light microscopy. Significant histological damage was seen at radiation doses above 295 Gy, and breakdown of the blood-brain barrier was observed only in tissue receiving a dose of 165 Gy or greater. Blood-brain barrier breakdown increased up to the 6-month time point, and thereafter appeared to stabilize or decrease. The area of blood-brain barrier disruption indicated by gadolinium-enhanced MR imaging was greater than that indicated by leakage of HRP.
Mark Bernstein, Tom Marotta, Patricia Stewart, Jennifer Glen, Lothar Resch and Mark Henkelman
Fred S. C. Kim, James T. Rutka, Mark Bernstein, Lothar Resch, Ellen Warner and Dominic Pantalony
✓ Granulocytic sarcoma usually occurs in the setting of leukemia and myeloproliferative disorders. Rarely, it can occur in isolation at various anatomical sites without hematological evidence of leukemia. The unique case of an elderly man presenting with right L2–3 radiculopathy is described. Intradural granulocytic sarcoma of the L-2 and L-3 nerve roots with extradural extension was found at surgery and he was treated with incomplete resection and antileukemic chemotherapy. Local recurrence at 3 months was treated with irradiation. Granulocytic sarcoma is frequently misdiagnosed and invariably progresses to acute leukemia. The chloroacetic acid esterase, granulocytic immunohistochemical markers, and electron microscopy appearance can aid in diagnosis. The prognosis is improved with initial aggressive antileukemic chemotherapy and local irradiation.
Douglas Kondziolka, Mark Bernstein, Lothar Resch, Charles H. Tator, J. F. Ross Fleming, R. G. Vanderlinden and Hart Schutz
✓ A retrospective clinical and pathological review of 905 consecutive brain tumor cases (excluding pituitary adenoma and recurrent tumor) was conducted to identify cases in which intratumoral hemorrhage was confirmed grossly and/or pathologically. There were 132 cases so identified, for an overall tumor hemorrhage rate of 14.6%; of these, 5.4% were classified as macroscopic and 9.2% as microscopic. The presence of hemorrhage was correlated with the neurological presentation. The highest hemorrhage rate (70.0%) was found in patients with prior neurological history who experienced apoplectic deterioration (acute-on-chronic presentation). Only 57.1% of patients with acute deterioration in the absence of prior neurological symptoms had hemorrhages. The highest hemorrhage rate for primary brain tumors was 29.2% for mixed oligodendroglioma/astrocytoma, while the highest hemorrhage rate for any tumor type was 50% for metastatic melanoma. The clinical relevance of tumor hemorrhage is discussed.