sodium-pertechnetate-tc-99m and Glioma

The preferential accumulation of sickle blood cells in tumor vasculature is demonstrated noninvasively using MRI and sickle red blood cells loaded with Gd-DTPA and invasively by two other techniques. The distribution of red blood cells in rat brain tumors relative to normal brains were measured using three separate techniques: MRI of Gd-DTPA loaded cells, fluorescent microscopy detection of Oregon Green 488 fluorescence conjugated to a streptavidin-biotin complex that binds to red blood cell surface proteins, and autoradiography using a technetium (99m)Tc-labeling kit. Labeled red cells were infused intravenously in rats with brain tumors. Sickle cells preferentially accumulated in tumor relative to normal brain, with highest concentrations near the tumor / normal tissue boundary, whereas control normal red cells did not preferentially aggregate at the tumor periphery. This demonstrates the potential of sickle red blood cells to accumulate in the abnormal tumor vessel network, and the ability to detect their aggregation noninvasively and at high spatial resolution using MRI. The application of the noninvasive measurement of sickle cells for imaging tumor neovasculature, or as a delivery tool for therapy, requires further study.

Topics: Anemia, Sickle Cell; Animals; Autoradiography; Brain; Brain Neoplasms; Carboxylic Acids; Cell Line, Tumor; Contrast Media; Erythrocytes; Fluorescent Dyes; Gadolinium DTPA; Glioma; Humans; Magnetic Resonance Imaging; Male; Microscopy, Confocal; Neoplasm Transplantation; Rats; Rats, Inbred F344; Sodium Pertechnetate Tc 99m

The number of cytoplasmic vesicles in the capillary endothelium was determined by ultrastructural morphometry and correlated with the uptake of technetium-99m pertechnetate used in brain scintigraphy. Ten gliomas were studied for uptake rates of 99mTc pertechnetate. Three gliomas from the different groups of uptake rates were quantitatively analyzed for cytoplasmic vesicle content. Capillaries of tumors without uptake had a low content of cytoplasmic vesicles, which was similar to that obtained in normal brain control. In tumors with low and moderate uptake rates, the cytoplasmic vesicles content increased significantly (p less than 0.05) by about 300% and 400%, respectively, as compared with that found in impermeable tumor and in normal brain. The correlation found between the cytoplasmic vesiculation of the endothelial cells in gliomas' capillaries and the uptake of 99mTc pertechnetate suggests that pinocytosis might be a factor in the uptake of the radionuclide. The present findings might be applicable to treatment with hydrophilic chemotherapeutic agents in moderate and highly permeable tumors.

Topics: Blood-Brain Barrier; Brain Neoplasms; Capillaries; Cytoplasmic Granules; Endothelium, Vascular; Glioma; Humans; Microscopy, Electron; Radionuclide Imaging; Sodium Pertechnetate Tc 99m

Topics: Adult; Aged; Astrocytoma; Brain Neoplasms; Cerebrovascular Disorders; Diagnosis, Differential; Female; Glioma; Humans; Male; Meningioma; Middle Aged; Radionuclide Imaging; Sodium Pertechnetate Tc 99m

The intensity of parenchymal brain lesions was compared using Tc-99m pertechnetate and Tc-99m phosphate. The following conclusions were made: 1. If the Tc-99m phosphate intensity is greater than the intensity of the Tc-99m pertechnetate scan, and the patient is evaluated within four weeks of ictus, the lesion is a CVA (P less than .001). 2. If the Tc-99m phosphate intensity is less than or equal to the intensity of the Tc-99m pertechnetate scan, and the patient is evaluated within four weeks of ictus, the parenchymal lesion is not a CVA (P less than .001). 3. If the evaluation takes place longer than six weeks after ictus, then no evaluation about the nature of the lesion can be made based upon uptake of Tc-99m phosphate and Tc-99m pertechnetate.

Topics: Adult; Brain Neoplasms; Diphosphonates; Glioblastoma; Glioma; Humans; Male; Middle Aged; Neoplasm Metastasis; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Technetium; Technetium Tc 99m Medronate; Tomography, X-Ray Computed

Topics: Astrocytoma; Brain; Brain Neoplasms; Chlormerodrin; Diuretics; Glioma; Neoplasms; Organomercury Compounds; Radionuclide Imaging; Serum Albumin; Serum Albumin, Radio-Iodinated; Sodium Pertechnetate Tc 99m; Technetium