technetium-tc-99m-tetrofosmin and Adenocarcinoma

The aim of this study was to assess the usefulness of 99Tcm-tetrofosmin for detecting tumours of the lungs and adjacent structures and to compare the results with those for 201Tl. In the 18 patients studied, there were 30 lesions in total. Dual-isotope SPET acquisitions were performed 10 min and 3 h after the administration of 99Tcm-tetrofosmin and 201Tl. Image quality and semi-quantitative parameters were evaluated for both tracers. All lesions were detected by the two radiopharmaceuticals on both the early and delayed images. In seven patients, the image quality of 99Tcm-tetrofosmin was better than that of 201Tl. For the detection of metastatic lymph nodes, the delayed 201Tl and the early 99Tcm-tetrofosmin images were superior. No significant difference was observed between the uptake ratios of the two tracers. 99Tcm-tetrofosmin showed significantly (P < 0.001) higher washout than 201Tl from both the lesions and normal lungs, although washout of 201Tl from normal lungs was significantly higher than that from the lesions. In conclusion, 99Tcm-tetrofosmin may be helpful for detecting tumours of the lungs and adjacent structures, but has limited applicability in differentiating between malignant and benign tumours and may not be used instead of 201Tl to detect malignant tumours of the lungs.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Carcinoma, Squamous Cell; Female; Humans; Image Processing, Computer-Assisted; Lung Neoplasms; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Thallium Radioisotopes; Thoracic Neoplasms; Tomography, Emission-Computed, Single-Photon

Technetium-99m-tetrofosmin is a new myocardial imaging agent which has yielded promising results compared to thallium-201. The tumour-seeking properties of the routinely used cardiac radiopharmaceuticals 201TI and 99mTc-methoxyisobutylisonitrile are well known. Here we report the results of a pilot study demonstrating 99mTc-tetrofosmin uptake in malignant lung tumours. Five patients with bronchial carcinoma, each in different stages of chemo- or radiotherapy, were imaged. Dynamic and static acquisitions were performed to evaluate the uptake and kinetics of 99mTc-tetrofosmin in the lesions. In four of the five patients localized tumour uptake of 99mTc-tetrofosmin was observed. Time to peak tumour activity and tracer washout in the tumour, myocardium and contralateral normal lung at 30 min post injection (p.i.) were determined. Tumour/normal lung, heart/tumour and heart/contralateral normal lung ratios were calculated for 5-10, 25-30 and 85-90 min p.i. The peak concentration in all tumours was reached at the end of the first minute. The mean tumour and contralateral normal lung washout rates of 99mTc-tetrofosmin at 30 min p.i. were 18.3% +/- 9.2% and 19.5% +/- 5.85% respectively. The tumour/contralateral normal lung ratio remained higher than 1.25 until 90 min p.i. in all four patients. It is concluded that 99mTc-tetrofosmin seems to be of value in lung tumour imaging, although larger studies are necessary to ascertain its sensitivity, specificity and usefulness in clinical practice.

Topics: Adenocarcinoma; Adult; Aged; Carcinoma, Squamous Cell; Female; Humans; Lung Neoplasms; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Pilot Projects; Radionuclide Imaging

In order to investigate the clinical significance of (99m)Tc-Tetrofosmin (TF) scintigraphy in the evaluation of lung cancer and mediastinal lymphoid node involvement, 33 patients with pulmonary neoplasmas were subjected to both (99m)Tc-TF scintigraphies and CT scans in one week before their operations or puncturations. All the images were judged visually and the emission images were analyzed with semi-quantitative methods in addition. The results of each group were compared. There was marked difference in target/non-target (T/N) ratio between the lung cancer group and the benign lesion group (P<0.001). Moreover, in the lung cancer group, T/N ratio in tomographies was significantly higher than that in planar images (P<0.01). The sensitivity and accuracy of semi-quantitative analysis in (99m)Tc-TF SPECT were significantly higher than those of CT in the diagnosis of pulmonary neoplasmas (P<0.05 and P<0.01 respectively), so was the sensitivity of (99m)Tc-TF SPECT vs CT in the diagnosis of mediastinal lymphoid node metastasis (P<0.05). It was also found that epidermoid squamous cell carcinomas and adenocarcinomas had a higher T/N ratio than in small cell carcinomas (P<0.05), and 2 h washout rate (WR) of adenocarcinomas was higher than that of epidermoid squamous cell carcinomas (P<0.05). In conclusion, (99m)Tc-TF scintigraphy showed a favorable diagnostic accuracy in appraising lung cancers and mediastinal lymph node metastases. Furthermore semi-quantitative technology can improve the accuracy, and is potential to offer some information about histological type of the cancer tissue. Therefore, (99m)Tc-TF scintigraphy will be a useful tool in the diagnosis and staging of lung cancer.

Topics: Adenocarcinoma; Carcinoma, Squamous Cell; Female; Humans; Lung Neoplasms; Lymphatic Metastasis; Male; Mediastinum; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

(99m)Tc-sestamibi (MIBI) and (99m)Tc-tetrofosmin (TF) are avid transport substrates recognized by the multidrug resistance (MDR) P-glycoprotein (Pgp). This study was designed to compare the properties of MIBI and TF in assessing the inhibition of Pgp by PSC833 in severe combined immunodeficient mice bearing MCF7 human breast tumors using SPECT imaging.. Animals with drug-sensitive (MCF/WT) and drug-resistant (MCF7/AdrR) tumors were treated by PSC833 and by carrier vehicle 1 h before imaging, respectively. Dynamic images were acquired for 30 min after intravenous injection of MIBI/TF using a SPECT system, FastSPECT. The biodistribution of MIBI and TF was determined at the end of the imaging session.. MCF7/WT in the absence and presence of PSC833 could be visualized by MIBI and TF imaging within 5 min and remained detectable for 30 min postinjection. MCF7/AdrR could be visualized only 2-5 min without PSC833 treatment but could be detected for 30 min with PSC833, very similar to MCF7/WT. MCF7/AdrR without PSC833 showed significantly greater radioactive washout than MCF7/WT and MCF7/AdrR with PSC833 treatment. PSC833 increased the accumulation (%ID/g) in MCF7/AdrR 3.0-fold (1.62+/-0.15 vs. 0.55+/-0.05, P<.05) for TF and 1.9-fold (1.21+/-0.04 vs. 0.64+/-0.05, P<.05) for MIBI but did not affect MCF7/WT.. The feasibility of MIBI and TF for assessment of MDR expression and inhibition was demonstrated in mice through FastSPECT imaging. The results indicate that TF may be at least comparable with MIBI in recognizing Pgp expression and modulation.

Topics: Adenocarcinoma; Animals; ATP Binding Cassette Transporter, Subfamily B, Member 1; Blotting, Western; Breast Neoplasms; Cyclosporins; Doxorubicin; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Female; Humans; Metabolic Clearance Rate; Mice; Mice, SCID; Organ Specificity; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Technetium Tc 99m Sestamibi; Tissue Distribution; Tomography, Emission-Computed, Single-Photon; Transplantation, Heterologous; Tumor Cells, Cultured

The aim of our study was to compare the usefulness of technetium-99m tetrofosmin (Tc-TF) mammoscintigraphy and ultrasonography for detecting breast cancer in mammographically dense breasts. This study included 32 female Taiwanese patients with indeterminate mammographic probability of malignancy due to mammographically dense breasts. Both Tc-TF mammoscintigraphy and ultrasonography were performed on each patient. Then, all of the 32 breast masses underwent biopsies or operations to obtain final pathological diagnoses. Based on the final pathological diagnoses, 24 women had breast cancer and eight had benign breast tumors among the 32 patients. Twenty cancers and one benign tumor had positive Tc-TF mammoscintigraphic findings. The sensitivity, specificity, and accuracy were 83, 88, and 84%, respectively. Twenty-two cancers and five benign tumors had positive ultrasonographic findings. The sensitivity, specificity, and accuracy were 92, 38, and 78%, respectively. To detect breast cancer in patients with nondiagnostic mammograms because of mammographically dense breasts, ultrasonography with its higher sensitivity is more suitable for screening breast masses. However, due to its higher specificity, Tc-TF mammoscintigraphy is useful to confirm the ultrasonographic findings.

Topics: Adenocarcinoma; Adult; Aged; Breast; Breast Neoplasms; Diagnosis, Differential; False Positive Reactions; Female; Humans; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Ultrasonography, Mammary

One hundred fifteen patients with 119 pulmonary lesions in which malignancy was suspected underwent a SPECT study with 99mTc-Tetrofosmin (TTF) to assess the possible factors involved in the uptake of the radiopharmaceutical. The TTF uptake rate in the lung tumor with respect to that of healthy tissue (TTF index) was evaluated in terms of: benignity and malignancy, histological type, stage, cell differentiation, size, necrosis, survival and the influence of P-glycoprotein (Pgp), detected by immunohistochemistry, on the TTF uptake. The mean TTF index in the 18 benign lesions studied was 1.01 0.05, while that of the 101 malignant lesions was 1.59 0.45 (p < 0.001), with a positive predictive value of 97.7% and a negative predictive value of 50%. The comparison of the histological types, degree of cell differentiation, necrosis and stage revealed no statistically significant differences. With respect to size, those tumors measuring > 3 cm showed greater uptake than smaller lesions. In patients with non-small cell lung cancer, a positive relationship was observed between the TTF index and survival, a circumstance that did not occur in patients with small cell lung cancer. In the cases in which the presence of Pgp was assessed, there was an inverse relationship between the TTF ratio and Pgp expression. In conclusion, thoracic SPECT with 99mTc-TTF has a high positive predictive value for the presence of lung cancer, although a negative study does not rule out the existence of the disease. The reason for this is the inverse relationship between 99mTc-TTF uptake and the density of Pgp expression.

Topics: Adenocarcinoma; Adolescent; Adult; Aged; Aged, 80 and over; ATP Binding Cassette Transporter, Subfamily B, Member 1; Carcinoma, Non-Small-Cell Lung; Carcinoma, Small Cell; Cell Differentiation; Colorectal Neoplasms; Female; Histiocytoma, Benign Fibrous; Humans; Lung; Lung Diseases; Lung Neoplasms; Male; Middle Aged; Neoplasm Proteins; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

99Tcm-methoxyisobutylisonitrile (99Tcm-MIBI) and 99Tcm-tetrofosmin are cationic tracers recognized by the efflux pump P-glycoprotein (Pgp). Verapamil has been shown to be a competitive inhibitor of Pgp, and was one of the first multidrug-resistant reversing agents identified. The aim of this preclinical in vitro study was to evaluate the effects of verapamil on the accumulation of 99Tcm-MIBI and 99Tcm-tetrofosmin in the human breast cancer cell lines MCF-7 and SK-BR-3 and in the human soft tissue sarcoma cell lines SW 982 and SW 1353, in comparison with respective control cells, i.e. without preincubation with verapamil. After preincubation with 10 or 100 microM of verapamil for 15 or 30 min, the 99Tcm-MIBI and 99Tcm-tetrofosmin accumulation in cells was assessed at 10, 30 and 60 min after incubation with these tracers. Addition of verapamil caused a decline in the accumulation of the two tracers at all incubation times, as compared with control cells. These effects of verapamil were neither dose- nor preincubation time-dependent in most cells. Our data indicate that verapamil is not a promising agent for increasing the sensitivity of scintigraphy with 99Tcm-MIBI or 99Tcm-tetrofosmin, or for evaluating Pgp tumour status in these types of tumours.

Topics: Adenocarcinoma; Breast Neoplasms; Calcium Channel Blockers; Cell Line; Cell Survival; Female; Humans; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Sarcoma; Soft Tissue Neoplasms; Technetium Tc 99m Sestamibi; Tumor Cells, Cultured; Verapamil

The kinetics and cellular uptake of 99mTc-2-hexakis 2-methoxyiso-butyl-isonitrile (MIBI) and 99mTc-1 ,2-bis[bis(2-ethoxyethyl)phosphino]ethane (tetrofosmin) into malignant versus nonmalignant human breast cell lines were investigated and compared.. At specific intervals after incubation at 37 degrees C and 22 degrees C with 99mTc-MIBI or 99mTc-tetrofosmin, the uptake characteristics of radiotracers into human adenocarcinoma breast cell lines MCF-7 and SK-BR-3 and human breast, nontumor cell line HBL-100 were assessed.. The uptake of 99mTc-MIBI and 99mTc-tetrofosmin was lower at an incubation temperature of 22 degrees C than that at 37 degrees C in the 3 cell lines. In MCF-7 and in SK-BR-3 cells the uptake of 99mTc-MIBI was significantly higher than the uptake of 99mTc-tetrofosmin. The uptake of 99mTc-MIBI was significantly higher into MCF-7 and SK-BR-3 cells than that into HBL-100 cells. In comparison with HBL-100 cells, uptake of 99mTc-tetrofosmin into SK-BR-3 cells was significantly higher, whereas uptake into MCF-7 cells was similar.. In vitro data suggest that 99mTc-MIBI may be a better tracer than 99mTc-tetrofosmin for discrimination between malignant and nonmalignant breast disease.

Topics: Adenocarcinoma; Biological Transport; Breast; Breast Neoplasms; Cell Line; Female; Humans; Kinetics; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Technetium Tc 99m Sestamibi; Tumor Cells, Cultured

Tc-99m-tetrofosmin is an agent to delineate cancer. To elucidate the usefulness of Tc-99m-tetrofosmin scintigraphy, we analyzed the relationship between the uptake of Tc-99m-tetrofosmin and histopathology in patients with lung cancer. SPECT studies were conducted twice: 15 minutes (early scan), and 60 minutes (delayed scan), after intravenous injection of 740 MBq Tc-99m-tetrofosmin. We calculated the retention index in order to evaluate the degree of Tc-99m-tetrofosmin retention in the primary tumor. The retention indices were significantly lower in squamous cell carcinoma than those of small cell carcinoma or adenocarcinoma. As the retention indices of Tc-99m-tetrofosmin were different in each histopathology, the index might play a part as a tumor marker of lung cancer.

Topics: Adenocarcinoma; Adolescent; Adult; Aged; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Child; Child, Preschool; Female; Humans; Infant; Lung; Lung Neoplasms; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

A 68-year-old male with recurrence of malignant follicular carcinoma-oxyphilic cell type of the thyroid after surgery underwent whole body scintigraphy with 131I-sodium iodide and 99Tcm-tetrofosmin (Myoview). 131I scanning demonstrated local uptake most likely to be in the normal remnant, but 99Tcm-Myoview images delineated recurrence of the carcinoma in the neck, with more extensive involvement. We believe that a combination of 131I and 99Tcm-tetrofosmin imaging may be useful to assess the extent of disease in patients with recurrent Hürthle cell type carcinoma of the thyroid.

Topics: Adenocarcinoma; Aged; Humans; Iodine Radioisotopes; Male; Neoplasm Recurrence, Local; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Thyroid Neoplasms

To evaluate the scintigraphy images of 99mTc-tetrofosmin in the primary hyperparathyroidism, we studied 8 patients, 5 males, with ages between 17 and 82 (median = 50) years old, and with clinical and laboratory manifestations of hyperparathyroidism (calcium metabolism and PTH elevated); parathyroid scintigraphy was realized after 20mCi (740 MBq) intravenously injection of 99mTc-tetrofosmin, and were acquired images (10, 60 and 120 min.) in a large field gamma camera. All patients were submitted to surgery. The histology of surgical specimens showed seven adenomas and one adenocarcinoma of parathyroids; the scintigraphic images showed four lesions in the inferior right lobe and four in the inferior left lobe of thyroid and have global correlation with surgical findings. There was preferential retention of the tracer in the earlier images (10 min) in all cases (100%) and in the later images (120 min.) in 5 cases (62.5%). In conclusion, the earlier images (10 min) were more diagnostic than the later in the primary hyperparathyroidism study. It is possible that other tumoral lesions have similar behavior with 99mTc-tetrofosmin.

Topics: Adenocarcinoma; Adenoma; Adolescent; Adult; Aged; Aged, 80 and over; Evaluation Studies as Topic; Female; Humans; Hyperparathyroidism; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Parathyroid Neoplasms; Radionuclide Imaging; Radiopharmaceuticals; Time Factors

We used thoracic SPECT to study the 99mTc-tetrofosmin (TF) uptake in patients with non-small-cell-lung-carcinoma (NSCLC). The results were compared with the percentage of P-glycoprotein (Pgp) found in flow cytometric analysis (FC) of samples of surgically-resected tumor tissue.. A total of 21 patients with NSCLC were studied by means 99mTC-TF and thoracic SPECT. Image analysis included the determination of the TF uptake rate in the lung mass with respect to that of healthy tissue of the contralateral lung. These rates were compared with the percentage of Pgp expression according to FC. FC analysis was also carried out in 16 samples of healthy lung tissue obtained from the patients.. In healthy lung tissue, the mean Pgp expression according to FC was 4.58 +/- 1.87%. The cutoff value used to differentiate between Pgp positive and Pgp negative tumors was considered to be the mean plus two standard deviations (8.32). The Pgp-positive tumors (> 8.32%) presented significantly lower uptake levels (1.28 +/- 0.39) than the Pgp-negative lesions (1.66 +/- 0.33) (p = 0.029).. There is a inverse correlation between the Pgp expression as determined by FC analysis and 99mTc-TF in NSCLC. Thus, this radiopharmaceutical provides rapid and non-invasive information on Pgp expression in these lesions.

Topics: Adenocarcinoma; Adult; Aged; ATP Binding Cassette Transporter, Subfamily B, Member 1; Carcinoma, Adenosquamous; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Female; Flow Cytometry; Humans; Lung; Lung Neoplasms; Male; Middle Aged; Neoplasm Proteins; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

Topics: Adenocarcinoma; Aged; Brain Neoplasms; Female; Humans; Lung Neoplasms; Lymphatic Metastasis; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

We evaluated the usefulness of 99Tcm-tetrofosmin imaging in lung cancer. The study sample comprised 46 patients with lung cancer. Single photon emission tomography was conducted after the intravenous injection of 740 MBq 99Tcm-tetrofosmin and 111 MBq 201T1-chloride. We obtained an uptake ratio (counts per pixel in the lesion/counts per pixel in contralateral normal lung) for each scan to evaluate the degree of uptake in the tumour. Our results demonstrate that 89.1% of the primary lung cancers were visualized by 99Tcm-tetrofosmin and 95.7% by 201T1. The difference between the 201T1 uptake ratio and the 99Tcm-tetrofosmin uptake ratio was significantly greater in squamous cell carcinomas than small cell carcinomas (P < 0.01) and tended to be greater in squamous cell carcinomas than adenocarcinomas (P = 0.093). This study has indicated that 99Tcm-tetrofosmin, like 201T1, is a highly effective agent in the delineation of lung cancer. The difference between the 99Tcm-tetrofosmin and 201T1 uptake ratios might provide further information regarding the histological type of lung cancer.

Topics: Adenocarcinoma; Aged; Aged, 80 and over; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Female; Humans; Lung Neoplasms; Male; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Sensitivity and Specificity; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon

Technetium-99m-tetrofosmin has emerged as a new radiopharmaceutical for myocardial imaging, in competition with 201Tl and 99mTc-MIBI. In this study, 99mTc-tetrofosmin was evaluated for its ability to detect malignant and benign lesions from single solid lung masses.. Forty-nine patients with a single solid lung mass based on chest radiograph findings received 99mTc-tetrofosmin SPECT of the chest to evaluate the value of 99mTc-tetrofosmin SPECT for detecting malignant and benign lesions.. Only 61% of the lung malignancies were detected by 99mTc-tetrofosmin SPECT of the chest, including 53% of epidermoid carcinoma (ca), 67% of adeno ca, 75% of small-cell ca, 0% of undifferentiated large-cell ca and 100% of other lung malignancies. In addition, 50% of the benign lesions were detected by chest 99mTc-tetrofosmin SPECT. The probability of tetrofosmin uptake in the mass was not related to mass size. The diagnostic sensitivity, specificity and accuracy were 61%, 50% and 59%, respectively, for differentiating malignant and benign lesions when diagnosing a single solid lung mass.. Technetium-99m-tetrofosmin SPECT of the chest is of little or no value for the detection of lung ca from single solid lung masses.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Female; Humans; Lung Diseases; Lung Neoplasms; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

Breast cancer, the most common malignancy in women, still poses a challenge to diagnostic procedures and therapy. Despite low specificity routine mammography is the method of choice to screen women for breast cancer. In the last years other additional diagnostic procedures such as high frequency ultrasonography (US) and especially magnetic resonance imaging (MRI) have improved breast cancer diagnosis. However, all these imaging methods are lacking in specificity which makes biopsy or surgery necessary. The purpose of our study was to evaluate prospectively the sensitivity, specificity, PPV and NPV of scintimammography with a new cationic complex Tc-99m tetrofosmin in patients with suspicious mammographic lesions. One hundred and thirty seven patients in whom mammography and/or high resolution ultrasonography (10 MHz) revealed suspicious breast lesions were studied with Tc-99m tetrofosmin scintimammography. In 84 of them biopsy and/or surgery was performed for histological evaluation. After intravenous injection of 555 MBq Tc-99m tetrofosmin planar images in anterior and lateral projections (5 min.p.i.) and SPECT imaging including 3-D-reconstruction (20 min.p.i.) were performed. Scintimammography was evaluated as negative, equivocal (+), probably (+2) or definitely (+3) positive. Planar scintimammography with Tc-99m tetrofosmin was negative in 46 patients (43 true negative-f.n; 3 false negative-f.n.) and positive in 38 patients (27 true positive-t.p.; 11 false positive-t.p.). Using SPECT imaging Tc-99m scintimammography was negative in 43 cases (41 t.n.; 2f.n.) and positive in 41 cases (28 t.p.; 13 t.p). Sensitivity of Tc-99m tetrofosmin scintimammography in this prospective study was 90%, specificity 80%, PPV 71% and NPV 93% for planar imaging and 93%, 76%, 68% and 95% for SPECT, respectively. Scintimammographic results in patients with suspicious breast lesion show, that Tc-99m tetrofosmin accumulates in breast cancer as well as in some fibroadenoma with high cellularity. However, the high NPV of 93 and 95% respectively excludes breast cancer in suspicious mammographic lesions to a very high degree and therefore reduces the need of biopsy and/or surgery in most of these patients.

Topics: Adenocarcinoma; Adult; Aged; Breast; Breast Neoplasms; Carcinoma, Ductal, Breast; Female; Humans; Magnetic Resonance Imaging; Mammography; Middle Aged; Neoplasms, Multiple Primary; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Ultrasonography, Mammary

Technetium-99m hexakis-2-methoxyisobutylisonitrile (MIBI), 99mTc-tetrofosmin and 99mTc-Q12 were all introduced for myocardial imaging but found additional applications as they are taken up by different tumours, enabling imaging of these lesions in patients. The aim of this study was to compare the uptake characteristics of these compounds in vitro in the human adenocarcinoma breast cell lines MCF-7 and ZR-75. It was shown that 99mTc-MIBI had the highest cellular uptake (15.9%+/-0.5% dose/mg protein after 60 min in MCF-7, and 14.2%+/-0.4% dose/mg protein in ZR-75), followed by 99mTc-tetrofosmin (6.8%+/-0.6% dose/mg protein in MCF-7, and 8. 2%+/-0.2% dose/mg protein in ZR-75) and 99mTc-Q12 (3.2%+/-0.1% dose/mg protein in MCF-7, and 3.5%+/-0.3% dose/mg protein in ZR-75 cells). For all three compounds tenfold differences in specific activity did not influence total cell-associated radioactivity. Uptake of 99mTc-MIBI and 99mTc-tetrofosmin was obviously lower at 4 degrees C than at 37 degrees C, whereas 99mTc-Q12 uptake showed only slight temperature dependence. When uptake was compared in cells grown to different cell densities (1 mg/ml cellular protein versus 0.3 mg/ml), no differences in uptake were detected when uptake was corrected for the amount of cellular protein present in the dishes. Furthermore, for all compounds it was shown that cellular radioactivity decreased rapidly after washing. Apart from the differences in cellular uptake of the three compounds after 60 min, no differences in residual cellular radioactivity after washing were found between the different compounds when expressed as a percentage of their 60-min uptake, suggesting that the efflux process of the radiolabelled compounds was similar. The differences in cell-associated activity after 60 min were thus presumably caused by differences in uptake. It was concluded that of the Tc-labelled compounds tested, 99mTc-MIBI had the highest cellular retention in both human breast tumour cell lines. However, for imaging in vivo not only radioactivity in the target organ is important, but also the ratio of radioactivity in the target versus that in the background. Therefore, further studies in vivo need to be performed to investigate which compound is the optimal imaging agent.

Topics: Adenocarcinoma; Breast Neoplasms; Female; Furans; Humans; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Technetium Tc 99m Sestamibi; Time Factors; Tumor Cells, Cultured

The routine mammogram remains the procedure of choice for screening asymptomatic women for breast cancer. However, it accounts for an elevated percentage of misdiagnosed breast nodules particularly in younger women with dense breast tissue or fibrocystic disease. New radiopharmaceuticals including labelled monoclonal antibodies, thalium-201 and technetium-99m sestamibi are under investigation as possible solutions to this issue. 99mTc-tetrofosmin (Myoview), like 99mTc-sestamibi, is a lipophilic, cationic myocardial imaging agent. Mitochondrial membrane potential appears to play a significant role in the uptake and/or retention of 99mTc-tetrofosmin. Twenty-seven female patients with suspected breast cancer were included in the study. Twenty mCi of 99mTc-tetrofosmin were administered intravenously. Imaging was begun 10 min post-injection. In twenty-three patients, breast cancer was detected using 99mTc-tetrofosmin scintigraphy. Two carcinomas were missed. In two patients, both breast scintigraphy and intraoperative biopsies were negative. Our preliminary results suggest that this product may have a role in the differentiation of benign from malignant lesions, and were encouraging in terms of its potential usefulness as a marker of malignancy.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Breast Neoplasms; Diagnosis, Differential; Female; Humans; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Sensitivity and Specificity

Technetium-99m tetrofosmin and thallium-201 lung SPECT imaging were performed in a patient with adenocarcinoma of the lung. Significant activities in the lung lesion were clearly depicted on both technetium-99m tetrofosmin and thallium-201 SPECT imaging. The early uptake, delayed uptake ratios and retention indices of the tumor were 2.75, 2.39 and -1.31 for thallium-201 imaging and 3.09, 2.27 and -26.5 for technetium-99m tetrofosmin imaging, respectively. This preliminary report suggests that technetium-99m tetrofosmin may have potential as a tumor imaging agent.

Topics: Adenocarcinoma; Aged; Evaluation Studies as Topic; Humans; Lung Neoplasms; Male; Organophosphorus Compounds; Organotechnetium Compounds; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Topics: Adenocarcinoma; Aged; Humans; Lung Neoplasms; Male; Organophosphorus Compounds; Organotechnetium Compounds; Tomography, Emission-Computed, Single-Photon

99Tcm-tetrofosmin planar imaging was performed in 30 patients with malignant and benign lung lesions. There were 21 cases of primary lung cancer (10 squamous cell, 5 small cell, 4 adenocarcinoma and 2 large cell) and 9 benign lung lesions (4 pneumonia, 3 tuberculosis, 1 infected bronchiectasis and 1 bronchiectasis obliterans). Anterior and posterior planar thorax images were obtained 30 min after the intravenous injection of 740 MBq (20 mCi) of 99Tcm-tetrofosmin. Visual and quantitative evaluations were performed. For the quantitative evaluation, regions of interest were drawn over the lesioned area (L) and over the contralateral non-lesioned area (N). Of 21 malignant primary lesions; 19 (90%) showed 99Tcm-tetrofosmin accumulation. Four (44%) of the nine benign lung lesions (3 cases of pneumonia and the one case of active tuberculosis) showed uptake. The mean L/N ratios for the malignant and benign lesions were 1.63 +/- 0.29 and 1.64 +/- 0.19, respectively. There were no significant differences (P > 0.05) in the L/N ratios of the malignant and benign lesions or the various histological types of cancer. In conclusion, 99Tcm-tetrofosmin was highly sensitive (90%) in detecting malignant lung lesions, but it had poor specificity (55%).

Topics: Adenocarcinoma; Adult; Aged; Bronchiectasis; Bronchiolitis Obliterans; Carcinoma, Large Cell; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Evaluation Studies as Topic; Female; Humans; Lung Diseases; Lung Neoplasms; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Pneumonia; Radionuclide Imaging; Radiopharmaceuticals; Sensitivity and Specificity; Tuberculosis, Pulmonary

This case report describes a 71-year-old man with a lung tumor in the posterior inferior segment of the right lung, detected on a screening chest radiograph. The patient underwent myocardial imaging with 99mTc tetrofosmin and 201Tl, using single photon emission CT (SPECT), and the tumor showed intense focal uptake of the radiotracer. This observation supports the recent suggestion that 99mTc tetrofosmin may be useful for oncologic imaging of lung carcinoma, and further studies may be warranted.

Topics: Adenocarcinoma; Aged; Heart; Humans; Lung Neoplasms; Male; Organophosphorus Compounds; Organotechnetium Compounds; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon

We conducted a preliminary study of captation of the new radiopharmaceutical 99mTc-tetrofosmin in cases of primary carcinoma of the lung, analyzing the results of 5 cases studied before surgery with single photon emission tomography (SPECT) of the lung. The results obtained by imaging were compared with those from surgery. Tumor size ranged between 3.5 and 9 cm. In all cases the images showed that captation of the radiotracer by the neoplasm was satisfactory, leaving the area of the tumor clearly distinguishable from normal adjacent lung tissue and giving no signs of interference caused by absorption of 99mTc-tetrofosmin by contiguous structures (heart or liver). Based on these preliminary results we assert that SPECT of the lung using 99mTc-tetrofosmin may be useful in the clinical diagnosis of malignant lung tumors, although further research must determine to what extent the technique can be relied upon.

Topics: Adenocarcinoma; Aged; Aged, 80 and over; Carcinoma, Bronchogenic; Carcinoma, Large Cell; Carcinoma, Squamous Cell; Drug Evaluation; Female; Humans; Lung Neoplasms; Lymphatic Metastasis; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Tomography, Emission-Computed, Single-Photon