succimer and Neurilemmoma

This study assessed pentavalent 99mTc-DMSA uptake in primary brain tumors and evaluated the relationship between retention and histologic malignancy.. SPECT images of the brain were obtained at 30 min and 3 hr after intravenous administration of approximately 555 MBq 99mTc(V)-DMSA in patients with brain tumors. Sixty studies were performed in 57 patients and 63 lesions were demonstrated: 11 glioblastomas, 13 anaplastic astrocytomas (Grade 3), 11 astrocytomas (Grade 2), 18 meningiomas and 10 schwannomas. Uptake ratios, retention ratio and retention index were calculated and compared with tumor histology and malignancy grade.. Approximately 95% of both benign and malignant primary brain tumors were demonstrated by 99mTc(V)-DMSA SPECT images. False negative was noted in three cases. The early uptake ratios were closely related to the tumor vascularity but had no statistically significant difference in the tumor histology or histologic malignancy. The delayed uptake ratio, retention ratio and retention index were higher in the malignant tumors than the benign tumors.. Technetium-99m(V)-DMSA washout from the tumor was highly dependent upon its histology and histologic malignancy. The delayed uptake ratio considerably reflected tumor histology and differentiated benign tumors from malignant tumors. The retention ratio and retention index significantly reflected tumor histology and histologic grade of primary brain tumors and clearly distinguished between benign and malignant tumors with statistically significant difference (p < 0.05). These results could suggest the clinical utility of 99mTc(V)-DMSA in imaging primary brain tumors and differentiating their histological malignancy grade noninvasively.

Topics: Adolescent; Adult; Aged; Astrocytoma; Brain Neoplasms; Child; Female; Glioblastoma; Glioma; Humans; Male; Meningeal Neoplasms; Meningioma; Middle Aged; Neurilemmoma; Oligodendroglioma; Organotechnetium Compounds; Radionuclide Imaging; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid

The diagnostic value of MRI and scintigraphy was studied in patients with Schwannomas of the upper or lower extremities. MRI (T1- and T2-weighted imaging), pentavalent 99mTc-dimercaptosuccinic acid and 67Ga-citrate scintigraphy were performed in 11 patients with 12 histologically proven benign Schwannomas. All six tumors with a maximum diameter > or = 3 cm showed marked accumulation of pentavalent 99mTc-dimercaptosuccinic acid, whereas they showed no uptake of 67Ga-citrate. MRI detected all of the tumors, and the lesions had a signal intensity equal to or slightly less than that of skeletal muscle on T1-weighted images and hyperintense to that of subcutaneous fat on T2-weighted images. MRI was superior to detect small Schwannomas of the extremities. A positive 99mTc-dimercaptosuccinic acid scan and a negative 67Ga-citrate scan however is useful to distinguish sarcoma with myxoid change from Schwannoma.

Topics: Adolescent; Adult; Citrates; Citric Acid; Extremities; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neurilemmoma; Organotechnetium Compounds; Radionuclide Imaging; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid

Tumor scintigraphy, using Tc(V)-99m dimercaptosuccinic acid (Tc(V)-DMS) was performed in 58 patients with soft tissue tumors, and the results were compared with that of Ga-67 citrate. Tc(V)-DMS was found to have a sensitivity of 90% for malignant tumors including aggressive fibromatosis compared to that of Ga-67 citrate, which was 56%. However, the specificity of Tc(V)-DMS for these tumors was 71% but with Ga-67 citrate the specificity was 80%. The imaging accuracy in soft tissue tumors with Tc(V)-DMS and Ga-67 citrate was 78% and 71%, respectively. Although the accumulation of Tc(V)-DMS has been detected in some benign soft tissue tumors, the reduced accumulation in inflammatory lesions compared to Ga-67 citrate was recognized, and Tc(V)-DMS could be of great use in the detection of extension or location of malignant soft tissue tumors.

Topics: Abscess; Adult; Aged; False Negative Reactions; False Positive Reactions; Female; Fibroma; Gallium Radioisotopes; Histiocytoma, Benign Fibrous; Humans; Lipoma; Male; Middle Aged; Neurilemmoma; Neuroectodermal Tumors, Primitive, Peripheral; Radionuclide Imaging; Soft Tissue Neoplasms; Succimer; Sulfhydryl Compounds; Synovitis; Technetium; Technetium Tc 99m Dimercaptosuccinic Acid