technetium-tc-99m-exametazime and Glioblastoma

Nicotinamide (NAM) and carbogen both have been shown to enhance the radiation effect in rodent tumour models and are currently being tested in clinical trials. These agents have demonstrated to act against hypoxia and one of their underlying mechanisms could be an increase of tumour blood perfusion.. To analyse the effect of both agents on normal brain perfusion and tumour perfusion in patients with glioblastoma.. Nineteen patients with glioblastoma were studied with 99mtechnetium-hexamethylpropyleneamine oxime single photon emission computed tomography (99mTc-HMPAO SPECT) before and after administration of carbogen and/or NAM. Another six patients were studied with the same procedure but without any flow modulator and were used as controls.. Although the variations between patients were large, no significant enhancement in mean tumour and normal brain perfusion could be demonstrated with NAM or carbogen compared to the control patients. Also no consistent changes in the mean perfusion ratio between tumour and surrounding normal brain were found, suggesting an absence of a selective perfusion effect.. No significant influence of carbogen and/or NAM on tumour perfusion and normal brain perfusion could be detected with SPECT in patients with glioblastoma.

Topics: Analysis of Variance; Brain Neoplasms; Carbon Dioxide; Cell Hypoxia; Cerebrovascular Circulation; Glioblastoma; Humans; Image Enhancement; Image Processing, Computer-Assisted; Niacinamide; Oxygen; Radiation-Sensitizing Agents; Radiopharmaceuticals; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The study was conducted to determine the association between dual-isotope single-photon emission computerized tomography (SPECT) scanning and histopathological findings of tumor recurrence and survival in patients treated with high-dose radiotherapy for glioblastoma multiforme.. Studies in which SPECT with 201Tl and 99mTc-hexamethypropyleneamine oxime (HMPAO) were used were performed 1 day before reoperation in 47 patients with glioblastoma multiforme who had previously been treated by surgery and high-dose radiotherapy. Maximum uptake of 201Tl in the lesion was expressed as a ratio to that in the contralateral scalp, and uptake of 99mTc-HMPAO was expressed as a ratio to that in the cerebellar cortex. Patients were stratified into groups based on the maximum radioisotope uptake values in their tumor beds. The significance of differences in patient gender, histological characteristics of tissue at reoperation, and SPECT uptake group with respect to 1-year survival was elucidated by using the chi-square statistic. Comparisons of patient ages and time to tumor recurrence as functions of 1-year survival were made using the t-test. Survival data at 1 year were presented according to the Kaplan-Meier method, and the significance of potential differences was evaluated using the log-rank method. The effects of different variables (tumor type, time to recurrence, and SPECT grouping) on long-term survival were evaluated using Cox proportional models that controlled for age and gender. All patients in Group I (201Tl ratio < 2 and 99mTc-HMPAO ratio < 0.5) showed radiation changes in their biopsy specimens: they had an 83.3% 1-year survival rate. Group II patients (201Tl ratio < 2 and 99mTc-HMPAO ratio of > or = 0.5 or 201Tl ratio between 2 and 3.5 regardless of 99mTc-HMPAO ratio) had predominantly infiltrating tumor (66.6%); they had a 29.2% 1-year survival rate. Almost all of the patients in Group III (201Tl ratio > 3.5 and 99mTc-HMPAO ratio > or = 0.5) had solid tumor (88.2%) and they had a 6.7% 1-year survival rate. Histological data were associated with 1-year survival (p < 0.01): however, SPECT grouping was more closely associated with 1-year survival (p < 0.001) and was the only variable significantly associated with long-term survival (p < 0.005).. Dual-isotope SPECT data correlate with histopathological findings made at reoperation and with survival in patients with malignant gliomas after surgical and high-dose radiation therapy.

Topics: Adolescent; Adult; Age Factors; Aged; Brain Neoplasms; Cerebellum; Chi-Square Distribution; Female; Glioblastoma; Humans; Linear Models; Male; Middle Aged; Neoplasm Invasiveness; Neoplasm Recurrence, Local; Proportional Hazards Models; Radiopharmaceuticals; Radiotherapy Dosage; Reoperation; Scalp; Sex Factors; Survival Rate; Technetium Tc 99m Exametazime; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon

99mTc complex of hexamethylpropylene amine oxime (99mTc-HMPAO), which has been used as a tracer for regional cerebral blood flow (rCBF), has been shown to localize in primary brain tumors with wide spectrum of its uptake. The causes of the wide spectrum of tumor uptake, however, has not been understood in detail. We performed autoradiographic study with this agent to get further knowledge about HMPAO distribution in 10 cases of transplanted rat gliomas. Eight cases of rat gliomas without tumor necrosis, showed decreased uptake of 99mTc-HMPAO in the autoradiography (average tumor/normal (T/N) uptake ratio: 0.75, range: 0.40-0.90). On the other hand, two cases with tumor necrosis revealed increased uptakes of this agent in central necrotic area. T/N uptake ratios of these two cases were 1.23 and 1.42, respectively. In addition, three patients with histologically proven glioblastoma with tumor necrosis were studied after administration of 20mCi 99mTc-HMPAO. Two out of three patients showed higher uptake of 99mTc-HMPAO in tumor necrotic area than the contralateral area. Our findings suggest that the necrotic area of brain tumor may retain 99mTc-HMPAO and causes an increased uptake.

Topics: Animals; Brain Neoplasms; Female; Glioblastoma; Gliosarcoma; Neoplasm Transplantation; Rats; Rats, Inbred F344; Technetium Tc 99m Exametazime; Tumor Cells, Cultured

A total of 17 patients with histologically proven diagnoses of low-grade astrocytoma (n = 4), high-grade astrocytoma (n = 8), lymphoma (n = 3), and meningioma (n = 2) were examined by using EPISTAR MR imaging. Meningiomas had the highest EPISTAR tumor/white matter contrast and low-grade astrocytomas and lymphomas the lowest. High-grade astrocytomas demonstrated elevated EPISTAR signal with marked regional heterogeneity. There was agreement between tumor vascularity by SPECT and EPISTAR in the five cases where both were done. Our results show that tumor vascularity can be assessed qualitatively by using EPISTAR without the need for contrast medium injection.

Topics: Adult; Aged; Astrocytoma; Brain Neoplasms; Cerebrovascular Circulation; Contrast Media; Echo-Planar Imaging; Female; Glioblastoma; Humans; Image Enhancement; Lymphoma; Magnetic Resonance Imaging; Male; Meningeal Neoplasms; Meningioma; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Nineteen patients with histologically diagnosed supratentorial cerebral neoplasms carried out CT and/or MRI, 201T1 SPECT and 99mTc-HM-PAO studies preoperatively. 99mTc-HM-PAO SPECT images revealed information about both tumoral perfusion and intracellular concentration of mediators converting 99mTc-HM-PAO to hydrophilic derivates (glutathione and other yet unknown factors) within viable tumoral cells while 201T1 SPECT images about permeability, extension of tumoral capillary network and viable tumoral cells presence. Basing on the different mechanisms of the tracer uptake, cerebral supratentorial tumors could be distinguished in three groups: 1) cerebral tumors presenting 201T1 very high uptake (201T1 index > 1.5) and homogeneous and high retention of 99mTc-HM-PAO (CBI > or = 1.05) (meningiomas, PRL adenoma); histologically these neoplasms presented very rich neoformed capillary network; 2) cerebral neoplasms with 201T1 high uptake (201T1 index > 1.5) and with inhomogeneous retention of 99Tc-HM-PAO (high grade gliomas amd metastasis); microscopically these tumors presented vascular proliferation, necrosis and high cellularity; 3) cerebral neoplasms characterized by 201T1 low uptake (201T1 index < 1.5) and lower retention of 99Tc-HM-PAO than cerebellum (low grade gliomas); at microscopic examination these neoplasms were characterized by absence of vascular proliferation and necrosis. These results suggest coupled 201T1/99Tc-HM-PAO SPECT is necessary to discriminate intra-axial from extra-axial tumor localization (lacking CT or MRI) and to detect the grade of malignancy of gliomas and tumor cell presence within necrotic areas.

Topics: Adult; Aged; Brain Neoplasms; Cerebral Hemorrhage; Female; Glioblastoma; Hematoma; Humans; Male; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

High-grade astrocytoma represents the most common primary malignant brain tumour in the adult, and is associated with high morbidity and mortality rates. The aim of this study was to investigate the prognostic value of 99Tcm-hexamethylpropyleneamine oxime (HMPAO) brain single photon emission computed tomography (SPECT) in predicting neurological function and tumour therapy response after surgical resection of astrocytoma. The correlation between 99Tcm-HMPAO studies and other noninvasive methods [computed tomography (CT), magnetic resonance imaging (MRI) and 201Tl (SPECT)] was evaluated. The clinical population included 21 patients with previous surgical debulking of astrocytoma. All patients were evaluated with 99Tcm-HMPAO brain SPECT. Seven patients, who suffered progressive clinical deterioration after radiotherapy, underwent dual-isotope SPECT imaging with 201Tl and 99Tcm-HMPAO. Neurological examinations and CT were performed in all patients. Magnetic resonance imaging was performed in seven patients. Prior to radiotherapy and/or chemotherapy, the patients with neurological improvement during the follow-up evaluation commonly showed less intense abnormal 99Tcm-HMPAO uptake than the patients without neurological improvement. In addition, after therapy none of the former patients had increased 99Tcm-HMPAO uptake. Most patients without neurological improvement had evidence of high focal uptake. Computed tomography and MRI usually demonstrated pathological contrast enhancement regardless of the presence or absence of improvement of neurological function. Foci of high 201Tl accumulation were observed on SPECT images in five patients. In four of these patients, the 99Tcm-HMPAO was greater than in normal brain, and in two patients the 99Tcm-HMPAO uptake was lower than in normal brain. One patient with decreased 99Tcm-HMPAO uptake in a medium-sized lesion had a normal 201Tl study. Our hypothesis that 99Tcm-HMPAO SPECT may be useful for providing prognostic information after surgical debulking of astrocytoma seems to be promising. Further studies are needed to document this new important role of 99Tcm-HMPAO SPECT.

Topics: Adolescent; Adult; Aged; Astrocytoma; Brain Neoplasms; Female; Glioblastoma; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Organotechnetium Compounds; Oximes; Prognosis; Technetium Tc 99m Exametazime; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Tumor perfusion and oxygenation status have been suggested as factors which may influence treatment outcome in cancer patients. Nuclear medicine assays of tumor perfusion [99mTc-hexamethylpropylenamine oxime (HMPAO)] and tumor hypoxia [123I-iodoazomycin arabinoside (IAZA)] have recently been developed and described. We report on measurements of perfusion and oxygenation status of 27 tumors in 22 patients using these probes. An inverse correlation between tumor uptake of HMPAO and IAZA was measured (p < 0.05), with severe perfusion deficit usually associated with an increased uptake of the hypoxic marker. This trend was observed for limited stage small-cell lung carcinoma, squamous-cell carcinoma of the head and neck, soft-tissue sarcoma, brain metastases from small-cell lung carcinoma and adenocarcinoma of the prostate as a group, but not for glioblastoma multiforme. Whereas each imaging agent can yield information about the physiological status of tumor and normal tissue, the information resulting from their combined use could be important in cancer therapy.

Topics: Brain Neoplasms; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Cell Hypoxia; Female; Glioblastoma; Head and Neck Neoplasms; Humans; Iodine Radioisotopes; Lung Neoplasms; Male; Nitroimidazoles; Organotechnetium Compounds; Oximes; Sarcoma; Soft Tissue Neoplasms; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Sequential thallium-201-chloride and technetium-99m-hexamethylpropyleneamine oxime single-photon emission computed tomography (SPECT) images were obtained in a patient with extracranial metastatic glioblastoma multiforme. Thallium-201 uptake was high (three times the scalp background) in all pathologically confirmed extracranial metastases and moderate (1.6 times scalp background) intracranially, where most biopsy specimens showed gliosis with scattered atypical astrocytes. Technetium-99m-HMPAO uptake was decreased intracranially in the right frontal and parietal lobes which had been irradiated. It was also decreased in one well-encapsulated scalp lesion and high in another scalp mass with less defined borders. Possible mechanisms of tumor uptake of these agents are reviewed.

Topics: Adult; Brain Neoplasms; Female; Glioblastoma; Humans; Organotechnetium Compounds; Oximes; Scalp; Skin Neoplasms; Technetium Tc 99m Exametazime; Thallium; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon

Topics: Adult; Aged; Amphetamines; Brain Neoplasms; Female; Glioblastoma; Hemangioma, Cavernous; Hemangiosarcoma; Humans; Iodine Radioisotopes; Iofetamine; Male; Meningeal Neoplasms; Meningioma; Middle Aged; Organometallic Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed; Xenon Radioisotopes

Topics: Amphetamines; Brain Neoplasms; Glioblastoma; Humans; Iodine Radioisotopes; Iofetamine; Male; Middle Aged; Organometallic Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed

In 10 patients with malignant gliomas, the intracerebral distribution of [99mTc]-hexamethylpropylene-amine oxime [( 99mTc]-HM-PAO) was studied with single photon emission computed tomography (SPECT) in comparison with C15O2 steady-state inhalation technique to measure cerebral blood flow using positron emission tomography (PET). In all instances, the cerebral [99mTc]-HM-PAO distribution was comparable with the regional pattern of cerebral blood flow (rCBF) observed with PET. This was confirmed by a significant correlation of tumor to cortex and tumor to white matter ratios between these two experimental methods. However, the contrast between high and low activity regions in the SPECT scans was significantly less than that in the PET scans. Contrast enhancement of the SPECT scans was accomplished using a correction formula proposed by Lassen.

Topics: Brain Neoplasms; Carbon Dioxide; Cerebrovascular Circulation; Glioblastoma; Humans; Organometallic Compounds; Oximes; Oxygen Radioisotopes; Technetium; Technetium Tc 99m Exametazime; Tomography, Emission-Computed