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PubMed1998

Tumor clearance of technetium 99m-sestamibi as a predictor of response to neoadjuvant chemotherapy for locally advanced breast cancer.

PURPOSE: Since we have previously shown that the efflux rate of technetium 99m (99mTc) sestamibi, a transport substrate of P-glycoprotein (Pgp), is directly correlated with Pgp levels in untreated breast carcinoma, we tested whether tumor clearance of 9mTc-sestamibi may be predictive of therapeutic response to neoadjuvant chemotherapy in patients with locally advanced breast cancer. PATIENTS AND METHODS: Thirty-nine patients with stage III disease, median tumor diameter 5.8 cm (range, 3 to 10) were enrolled onto this prospective clinical trial and underwent 99mTc-sestamibi scan before neoadjuvant chemotherapy. Patients were injected intravenously (i.v.) with 740 MBq of 99mTc-sestamibi; a 15-minute dynamic study was performed, and static planar images were obtained at 0.5, 1, 2, and 4 hours. The time to half clearance of 99mTc-sestamibi was calculated in each patient from decay corrected time-activity curves using a monoexponential fitting. Patients were treated with epirubicin 150 mg/m2 i.v. every 2 weeks for three courses and then underwent surgery within 3 weeks from the completion of chemotherapy. Residual tumor was assessed by pathologic examination of mastectomy specimens. RESULTS: Seventeen of 39 patients showed a rapid tumor clearance of 9mTc-sestamibi (time to half clearance [t1/2] < or = 204 minutes) and 15 of these 17 (88%) showed a highly cellular macroscopic residual tumor at histology that indicated lack of tumor response to neoadjuvant chemotherapy. In contrast, only eight of 22 (36%) with prolonged retention of 99mTc-sestamibi (t1/2 > 204 minutes) showed residual macroscopic tumor at histology (Fisher's exact test, P < .01). CONCLUSION: A rapid tumor clearance of 99mTc-sestamibi may predict lack of tumor response to neoadjuvant chemotherapy with drugs affected by the multidrug-resistant phenotype in patients with locally advanced breast carcinoma.

Adult↗
PubMed1998

Radioimmunoscintigraphy of recurrent, metastatic, or occult colorectal cancer with technetium 99m-labeled totally human monoclonal antibody 88BV59: results of pivotal, phase III multicenter studies.

PURPOSE: To assess the performance and potential clinical impact of a totally human monoclonal antibody, 88BV59 (HumaSPECT) (INTRACEL, Corp, Rockville, MD), in 202 assessable presurgical patients with recurrent, metastatic, or occult colorectal cancer. METHODS: 88BV59, labeled with technetium Tc 99m (99mTc) (HumaSPECT-Tc), was injected intravenously, and planar and single photon emission tomography (SPECT) images were obtained 14 to 20 hours postinjection. Surgical and pathologic verification of tumor were used as the standard against which the performance of HumaSPECT-Tc imaging and computed tomography (CT) analysis were evaluated. RESULTS: All patients entered onto the recurrent disease study had at least one tumor site defined on CT. The sensitivity of HumaSPECT-Tc in those CT-positive patients was 87%. The specificity of HumaSPECT-Tc was 57% compared with 17% for CT and the difference was statistically significant (P < .001). The diagnostic information provided by HumaSPECT-Tc significantly (P < .001) improved the accuracy of the identification of resectable and nonresectable disease over that of CT (80% v 62%). HumaSPECT-Tc scans resulted in a significant (P < .001) reduction versus CT in terms of the proportion of patients understaged (27% v 41%) and overstaged (4% v 26%). In patients with occult disease (increasing carcinoembryonic antigen [CEA] titer, negative diagnostic work-up, negative CT), HumaSPECT-Tc correctly identified disease in 15 of 22 (68%) patients. HumaSPECT-Tc images provided additional clinical data that would have affected patient management decisions in 40 of 202 (19.8%) patients. In 365 patients who received 88BV59, only a single detectable human anti-human antibody (HAHA) response (90 ng/mL) at 9 weeks postinfusion was observed. CONCLUSION: HumaSPECT-Tc can provide important and accurate information about the presence and location of disease in patients with a high clinical suspicion of metastatic or recurrent colorectal cancer and either positive (known disease) or negative (occult disease) CT scans.

Adult↗
PubMed1994

Preoperative localization of parathyroid tissue with technetium-99m sestamibi 123I subtraction scanning.

To evaluate the utility of technetium-99m (Tc-99m) sestamibi for visualization of functioning parathyroid tissue, 14 subjects underwent Tc-99m sestamibi 123I subtraction scanning as part of the preoperative evaluation for hyperparathyroidism. Informative scans were obtained in 13 subjects, including 7 patients with recurrent or persistent hyperparathyroidism, and correctly identified the location of the hyperfunctioning parathyroid tissue found at surgery. In all informative patients, hyperparathyroidism was due to adenomatous disease or hyperplasia secondary to renal failure. Successful scans were obtained with glands as small as 220 mg. In the lone patient in whom Tc-99m sestamibi scanning failed to localize hyperfunctioning parathyroid tissue, surgery revealed a 1700-mg hyperplastic parathyroid neoplasm in the neck. In no case did a Tc-99m sestamibi scan suggest parathyroid tissue where there was none. In 1 case, a patient presented with persistent hyperparathyroidism after 1 neck and a second combined neck and mediastinal exploration. Tc-99m sestamibi imaging revealed uptake in the periaortic region, and a 570-mg adenoma was found in the aortopulmonary window. Using only initial studies, prospective evaluation provided a sensitivity of 78.5% and a positive predictive value of 100%. After repeat studies in 5 patients, 2 of 3 patients with initially negative results and technically deficient scans became positive on restudy. Inclusion of these studies increased sensitivity to 93%. Tc-99m sestamibi 123I subtraction scanning appears to be a reliable noninvasive method for preoperative localization of hyperfunctioning parathyroid tissue.

Adult↗
PubMed1975

Study in cerebrovascular disease: brain scanning with technetium 99m pertechnetate; clinical correlations.

A prospective brain scanning study using technetium 99m pertechnetate was performed in 84 patients with cerebral infarction. No correlation was found between vascular angiographic findings and the frequency of positive scans. A comparison with clinical motor and mental evaluation showed a good correlation between abnormal scans (58 percent) and poor initial test resutls. A half-life of 17 days characterized the time course of positive scans according to their density and abnormal radioisotopic uptake area.

Activities of Daily Living↗
PubMed1977

Localization of technetium-99m diphosphonate in acutely injured muscle. Relationship to muscle calcium deposition.

In rats with experimental ischemic myopathy, there was a significant correlation (r = 0.778, p less than 0.001) between muscle uptake of technetium-99m (99mTc) diphosphonate and tissue calcium concentration. In addition, the accumulation of both calcium and 99mTc-diphosphonate in acutely injured muscles was further increased in rats with vitamin D-induced hypercalcemia. Histologic studies demonstrated staining of damaged muscle fibers with alizarin red, indicating the presence of microcrystalline or ultramicrocrystalline calcium salts. Staining of muscle fibers was most intense in the outer marginal zones of individual microscopic infarcts. Our results suggest that the uptake of 99mTc-diphosphonate in acutely damaged skeletal muscle is directly related to the deposition of calcium salts within the injured muscle fibers.

Acute Disease↗
PubMed1993

Variations in regional cerebral blood flow investigated by single photon emission computed tomography with technetium-99m-d, l-hexamethylpropyleneamineoxime = l-h during temporary clipping in intracranial aneurysm surgery: preliminary results.

Single photon emission computed tomography with technetium-99m-d, l-hexamethylpropyleneamineoxime was used to assess variations in regional cerebral blood flow during temporary clipping in the course of intracranial aneurysm surgery and during the postoperative period in 20 patients, 14 of whom underwent temporary clipping. Of these 14 patients (Group A), 9 had aneurysms of the anterior communicating artery, 2 had aneurysms of the middle cerebral artery, and 3 had aneurysms of the carotid siphon. Temporary clips were applied, according to the site of the lesion, on A1, on the trunk of the middle cerebral artery, or on the trunk of the internal carotid artery. The occlusion time ranged from 2 to 31 minutes. The six patients who did not undergo temporary clipping served as controls (Group B), as follows: three had aneurysms of the posterior communicating artery, one of the anterior communicating artery, one of the middle cerebral artery, and one of the internal carotid artery. All patients were investigated with cerebral single photon emission computed tomography preoperatively, perioperatively, and postoperatively. In all the patients of Group A, the preliminary results of the study show a sharp fall in the perfusion of the territories of the temporarily clipped parent vessel and practically a complete recovery within 2 to 7 days of surgery, with no significant neurological symptoms. No similar disturbance of perfusion was found in the patients of Group B.

Adult↗
PubMed1991

Simultaneous assessment of left ventricular wall motion and myocardial perfusion at rest and during exercise by technetium-99m methoxy isobutyl isonitrile.

First-pass radionuclide ventriculography followed by myocardial SPECT with technetium-99m methoxy isobutyl isonitrile (Tc-99m MIBI) was performed on 12 patients with suspected coronary artery disease at rest and during exercise. Left ventricular wall motion and myocardial perfusion were assessed simultaneously and compared on a segment-by-segment basis. Segmental agreement between Tc-99m MIBI and Tl-201 with regard to the presence of perfusion defects was 95% (57/60) at rest and 93% (37/40) during exercise. With respect to the assessment of myocardial ischemia and/or infarction, abnormalities in regional wall motion agreed with the presence of myocardial perfusion defects in 18 out of 21 segments (86%). Simultaneous evaluation of regional wall motion and myocardial perfusion by Tc-99m MIBI may provide useful information for the assessment of myocardial ischemia.

Adult↗
PubMed1999

New method of estimating myocardial infarct size using technetium-99m pyrophosphate and thallium-201 dual single photon emission computed tomography imaging.

A new method was devised to estimate infarct size using dual single photon emission computed tomography with thallium-201 and technetium-99m pyrophosphate. Designating the ratio of infarct area to whole myocardial volume as %MI, the correlation of %MI with other markers of left ventricular dysfunction was examined: peak creatine kinase, ejection fraction and left ventricular asynergy. As %MI correlated well with these markers, it is considered that %MI will be useful for estimating infarct size and predicting the severity of left ventricular dysfunction in the early stage of acute myocardial infarction.

Adult↗
PubMed2005

Usefulness of technetium-99m methoxyisobutylisonitrile single-photon emission computed tomography and computed tomography in the evaluation of cervical lymph node metastasis.

The aim of this study was to compare the effectiveness of technetium-99m methoxyisobutylisonitrile ((99m)Tc-MIBI) single-photon emission computed tomography (SPECT) and computed tomography (CT) in evaluating cervical lymph node metastasis of head and neck cancer. Histopathologic results of 166 cervical lymph node levels in 31 neck-dissected patients were compared with pre-operative CT and (99m)Tc-MIBI SPECT findings about cervical lymph node metastasis, retrospectively. Sensitivity, specificity and predictability of CT and (99m)Tc-MIBI SPECT were 68.2, 93.1 and 89.8 per cent and 59.1, 87.5 and 83.7 per cent, respectively. When analysing CT and(99m)Tc-MIBI SPECT together, sensitivity and specificity were 86.4 and 99.3 per cent, respectively. The combined use of (99m)Tc-MIBI SPECT and CT could increase the accuracy of cervical lymph node metastases detection, compared with separate use of either (99m)Tc-MIBI SPECT or CT.

Adult↗
PubMed1976

Technetium-99m labelled imidodiphosphate: an improved bone-scanning radiopharmaceutical.

Technetium-99m labelled imidodiphosphate was prepared in the presence of stannous ions. It was evaluated as a bone-scanning agent in animals and patients. Comparative tissue distribution studies in mice showed a relatively higher uptake of radioactivity in bone when 99Tcm -labelled pyrophosphate and diphosphonate. Accumulation of radioactivity in soft tissues, especially kidneys, was less with this radiopharmaceutical. Results in patients were most satisfactory in delineating skeletal bone and identifying bone lesions with relatively small tracer doses of the radiopharmaceutical.

Animals↗
PubMed1980

Processing of liver dynamic studies with technetium-labelled sulphur colloid.

The uptake of technetium-labelled sulphur colloid by the liver was investigated by monitoring 69 patients on a gamma camera/computer system. Following an intravenous injection 30 half-minute frames were collected and summed to give a composite view. Regions of interest were drawn round the liver and over the aorta and corresponding activity-time curves were formed. A simple physiological model has been assumed and two parameters, namely total uptake and rate of uptake, were shown to give fairly good separation between the classes of normal, cirrhosis, space occupying lesions, reticulosis and hepatitis. Furthermore the uptake rate-constant was also shown to be a useful indication of whether or not a reticulosis or hepatitis was in an acute phase. Principal components analysis was also applied to the liver curves producing two relevant components. However, a plot of the first against the second yielded no better separation of classes than that obtained by the model.

Colloids↗
PubMed1988

The study of regional cerebral blood flow in stroke patients using technetium 99m HMPAO.

Seventeen patients who had suffered a stroke in the previous 72 h have been studied using technetium 99m hexamethyl propylene amine oxime (HMPAO) to assess cerebral blood flow. Comparison of the scan appearances and clinical signs were made in all cases. Twelve of the patients had a repeat HMPAO scan 14 days later, together with further clinical assessment. Good correlation between the size and site of perfusion deficit and the clinical signs was found in 14 of the patients. When the results of the 12 patients who had repeat scans were examined at 14 days the correlation between the scan and the clinical signs was less accurate and it seems unlikely that the assessment of the size of cerebral infarction as demonstrated by an HMPAO scan will provide an accurate prognostic sign. Three of the patients, all of whom had suffered right hemiplegia and were dysphasic, had regions of increased uptake adjacent to the area of ischaemia and non deteriorated clinically; it is thought that this sign may represent hyperperfusion around infarction and indicates a fair prognosis. In patients suffering from transient neurological symptoms, the use of HMPAO may be useful by excluding the presence of other cerebral disease.

Aged↗
PubMed1989

Comparison of techniques for thallium-201-technetium-99m parathyroid imaging.

It is impracticable to compare the variety of techniques advocated for thallium-technetium (Tl-Tc) subtraction parathyroid imaging by repeated studies in patients. We therefore carried out studies using a phantom assembly to simulate thyroid and parathyroid in the neck, containing activities of 99Tcm and 201Tl similar to those likely to be present in patient imaging. An initial study of imaging protocol confirmed that correction for scatter from 99Tcm in the 201Tl window usefully improved the image. After making a preliminary selection of gamma cameras and collimators it was found that the GE Maxicamera 400T just visualized the 0.3 g "parathyroid" in a 5 min image with the pinhole collimator and 6 mm insert (A). It performed slightly less well with the HR converging collimator (B) and only marginally better with the 4 mm insert (C), but this is unduly slow unless it is placed close enough to limit the field of view unacceptably. The Siemens Orbiter 75 ZLC with special thyroid collimator (D) gave results similar to (A), is convenient for positioning the patient and is very suitable for parathyroid imaging.

Models, Structural↗
PubMed1993

Comparison of technetium 99m nanocolloid and indium 111 leucocytes in the diagnosis of orthopaedic infections.

It has been suggested that technetium 99m nanocolloid is as effective an inflammatory radiopharmaceutical as indium 111 leucocytes. This study compares the efficacy of 99Tcm nanocolloid and 111In leucocytes in the detection of orthopaedic infection in 19 patients with a high clinical suspicion of infection. The two scintigrams were performed within 24 h of each other. A scintigram was considered positive where there was an increase in tracer uptake at the site of interest. Concordance rate of 73% was achieved. The numbers of false positives with 111In leucocytes and 99Tcm nanocolloid were three and six respectively. The single false negative in both was of a patient with tuberculous spondylodiscitis. Sensitivity was 75% in both. Specificities were 79% and 60% for 111In leucocytes and 99Tcm nanocolloid respectively. Positive Predictive Value was only 33% with 99Tcm nanocolloid and 50% with 111In leucocytes. 99Tcm nanocolloid also proved less reliable in accurately detecting infected prostheses. We conclude that 99Tcm nanocolloid cannot replace 111In leucocytes in the diagnosis of orthopaedic infections.

Adult↗
PubMed1994

Diagnostic pharmaco-scintigraphy with hepatic intra-arterial technetium-99m macroaggregated albumin in the determination of tumour to non-tumour uptake ratio in hepatocellular carcinoma.

Between October 1990 and March 1993, 124 patients who had hepatocellular carcinoma (HCC) underwent diagnostic pharmaco-scintigraphy with hepatic intraarterial technetium-99m macroaggregated albumin (TcMAA) to determine the tumourous to non-tumourous liver tissue uptake ratio (T/N ratio). There were 110 males and 14 females. Ages ranged from 16 to 73 with a median of 55 years. The range of T/N ratio was 0.7 to 19.3 with a median of 3.8. 12 patients with inoperable HCC were subsequently selected by predetermined criteria to undergo treatment with hepatic intraarterial yttrium-90 microspheres and the T/N ratios in these patients were validated by beta probe dosimetry and liquid scintillation count of multiple liver biopsies. The T/N ratio determined by preoperative diagnostic TcMAA scan correlated well with intraoperative beta probe dosimetry, with coefficient of correlation r = 0.82. Preoperative TcMAA scan also correlated well with liquid scintillation count of biopsy specimens, with r = 0.96. We conclude that TcMAA scan can be used to determine the T/N ratio in patients with HCC, thus allowing better selection of patients with inoperable tumours for loco-regional therapy.

Adolescent↗
PubMed1994

An audit of paediatric technetium-99m methylene diphosphonate bone scans.

Eighty-nine Technetium-99m-MDP scans performed between January 1987 and June 1990 at the Leicester Royal Infirmary were reviewed with regard to the indication, patient outcome and value of the scans in the patients' management. The significant finding was the value of a normal scan in the management of children with chronic pain.

Acute Disease↗
PubMed1994

Case report: uptake of pentavalent technetium-99m dimercaptosuccinic acid by pigmented villonodular synovitis: comparison with computed tomography, magnetic resonance imaging and gallium-67 scintigraphy.

The scintigraphic findings of a patient with pigmented villonodular synovitis are described and compared with the computed tomography and magnetic resonance imaging data. Intense uptake of pentavalent technetium-99m dimercaptosuccinic acid without gallium-67 citrate uptake indicates that pigmented villonodular synovitis has the features of a hyperplastic or neoplastic lesion rather than an inflammatory lesion from the point of view of nuclear medicine.

Adult↗
PubMed1994

Technetium-99m hexamethylpropyleneamineoxime labelled leucocyte scanning in the initial diagnosis of Crohn's disease.

The technetium hexamethylpropyleneamineoxime labelled white cell scan (WCS) is not widely used as a screening test for Crohn's disease primarily because, though sensitive, it is perceived as being insufficiently specific. A series of 42 patients screened for Crohn's disease by this method was analysed retrospectively. The sensitivity was 100% and specificity 91%. This performance was maintained in a subgroup of these patients with very low prevalence of disease. If appropriate criteria for interpretation are used the WCS is a specific as well as a sensitive screening test for Crohn's disease.

Adolescent↗