Small cell lung cancer with SYN2::PPARG fusion.

INTRODUCTION: Small cell lung cancer (SCLC) accounts for 15% of lung cancers worldwide. It is an aggressive tumor that is typically diagnosed at an advanced stage. Treatment involves chemo-immunotherapy and/or radiotherapy. Identifying druggable targets activated by specific genetic alterations represents a significant challenge in improving patient outcomes. METHODS: We conducted a retrospective examination of molecular findings in lung cancer patients' records from 2021 to 2022. We discovered a unique case of SCLC harboring the SYN2-PPARG fusion. Histopathological analysis confirmed the diagnosis of SCLC. CASE REPORT: A 60-year-old woman, a heavy smoker, came to our attention due to a persistent cough with slight hemoptysis. Imaging, including axial contrast-enhanced computed tomography, revealed an advanced disease with extra-thoracic spread. Tumor histology showed a sheet-like proliferation of small-sized cells with a neuroendocrine phenotype and a high proliferation tumor cell fraction. Molecular genetic analysis using NGS approach revealed a fusion involving the SYN2 and PPARG genes. CONCLUSION: The SYN2-PPARG fusion has recently been documented in sinonasal adenocarcinoma and has been reported in only a single SCLC case previously. Highlighting the molecular heterogeneity within this aggressive form of lung cancer could potentially aid in the selection of specific therapies.

Prevalence, awareness and determinants of contraceptive use in Qatari women.

We determined the knowledge of, attitude to and practice of contraception and the associated sociodemographic factors among a representative sample 1130 Qatari married women aged 18-49 years. Data were collected by questionnaire. The mean age of the women was 32.5 (SD 7.6) years. The vast majority (94.6%) knew about contraception but of these 1070, only 694 (64.9%) were in favour of contraception. Knowledge of contraception increased with increasing level of education (P < 0.001), but decreased the lower the household income (P = 0.002). Only 511 (47.8%) women were currently using contraceptives, which was significantly associated with age, husband's age, years of marriage, education level, income level and attitude to family planning. The most commonly known and used contraceptives were intrauterine device and pills. Friends were the most common source of knowledge about family planning method (80.0%).

Estimating development of Aphis pomi (De Geer) (Homoptera: Aphididae) using linear and nonlinear models.

The development period of immature stages of the green apple aphid, Aphis pomi (De Geer) (Homoptera: Aphididae), at 6 constant temperature regimes (20, 24, 28, 30, 32, and 34 degrees C) were modelled to determine mathematical functions for simulating aphid development. 10 models (one linear and nine nonlinear), were used to describe the relationships between temperature and development rate of the different instars and stages of Aphis pomi (DeGeer) at constant temperatures. All models (except logistic and linear) provided accurate values for the optimum temperature for the Ist, 2nd, 3rd, 4th instars larvae and for the total development. The results suggest that among four models (Hilbert & Logan, Lactin, Briere, Analytis) that estimate all three parameters (tmin, topt, tmax), Lactin and Hilbert - Logan models gave the most suitable fit of data.

Targeting Bone Marrow to Potentiate the Anti-Tumor Effect of Tyrosine Kinase Inhibitor in Preclinical Rat Model of Human Glioblastoma.

Antiangiogenic agents caused paradoxical increase in pro-growth and pro-angiogenic factors and caused tumor growth in glioblastoma (GBM). It is hypothesized that paradoxical increase in pro-angiogenic factors would mobilize Bone Marrow Derived Cells (BMDCs) to the treated tumor and cause refractory tumor growth. The purposes of the studies were to determine whether whole body irradiation (WBIR) or a CXCR4 antagonist (AMD3100) will potentiate the effect of vatalanib (a VEGFR2 tyrosine kinase inhibitor) and prevent the refractory growth of GBM. Human GBM were grown orthotopically in three groups of rats (control, pretreated with WBIR and AMD3100) and randomly selected for vehicle or vatalanib treatments for 2 weeks. Then all animals underwent Magnetic Resonance Imaging (MRI) followed by euthanasia and histochemical analysis. Tumor volume and different vascular parameters (plasma volume (vp), forward transfer constant (Ktrans), back flow constant (kep), extravascular extracellular space volume (ve) were determined from MRI. In control group, vatalanib treatment increased the tumor growth significantly compared to that of vehicle treatment but by preventing the mobilization of BMDCs and interaction of CXCR4-SDF-1 using WBIR and ADM3100, respectively, paradoxical growth of tumor was controlled. Pretreatment with WBIR or AMD3100 also decreased tumor cell migration, despite the fact that ADM3100 increased the accumulation of M1 and M2 macrophages in the tumors. Vatalanib also increased Ktrans and ve in control animals but both of the vascular parameters were decreased when the animals were pretreated with WBIR and AMD3100. In conclusion, depleting bone marrow cells or CXCR4 interaction can potentiate the effect of vatalanib.

Uptake of technetium-99m-tetrofosmin, technetium-99m-MIBI and thallium-201 in tumor cell lines.

UNLABELLED: We investigated the kinetics, cellular uptake and intracellular distribution of 99mTc-tetrofosmin in tumor cell lines and compared them with those of 99mTc-MIBI and 201TI. METHODS: At specific intervals after incubation with radiotracers, cellular uptake was determined. Cells were also treated with nigericin, carbonyl cyanide m-chloro-phenylhydrazone (CCCP) and ouabain to determine their effects on the uptake of the tracers. RESULTS: Each tracer showed similar uptake kinetics in both cell lines, and a steady-state was maintained for at least 4 hr. Nigericin stimulated the uptake of both 99mTc-tetrofosmin and 99mTc-MIBI in HBL-2 cells, although it inhibited their uptake in SW-13 cells. Nigericin also inhibited 90% of 201TI uptake in both cell lines. Addition of CCCP caused 73%-97% release of accumulated 99mTc-MIBI from both cell lines with or without nigericin pretreatment, indicating that most of the accumulated 99mTc-MIBI was related to mitochondria. The effect of CCCP on accumulated 99mTc-tetrofosmin was less marked than that on 99mTc-MIBI in both cell lines, indicating that only a part of accumulated 99mTc-tetrofosmin, was related to mitochondria. Ouabain preincubation inhibited 74%-77% and 51%-53% of 201TI uptake in HBL-2 and SW-13 cells, respectively, as well as inhibited 22%-31% uptake of 99mTc-tetrofosmin in both HBL-2 and SW-13 cells. Uptake by the dead cells of either cell line was negligible for each tracer. CONCLUSION: Technetium-99m-tetrofosmin uptake depends on both cell membrane and mitochondrial potentials. Only a small fraction of 99mTc-tetrofosmin accumulates inside the mitochondria, while most 99mTc-MIBI accumulates inside the mitochondria. Thallium-201 uptake is partly independent of the Na+, K+ pump.

Technetium-99m-tetrofosmin, technetium-99m-MIBI and thallium-201 uptake in rat myocardial cells.

UNLABELLED: The mechanisms of uptake and intracellular distribution of 99mTc-tetrofosmin, 99mTc-MIBI and 201TI and the behaviors of 99mTc-tetrofosmin and 99mTc-MIBI in relation to Na+ were studied with primary cultures of myocardial cells. METHODS: Both the uptake and the washout of the tracers were sequentially measured. The cells were treated with ouabain, bumetanide, tetrodotoxin, dimethyl amiloride (DMA), nigericin and carbonyl cyanide m-chlorophenylhydrazone (CCCP) to observe the effects of the uptake and intracellular distribution of the traders. Cells equilibrated in buffers with or without Na+ were treated with monensin and DMA to evaluate the effect of Na+ on the accumulation of the tracers. RESULTS: Despite the similarities in uptake kinetics, there was a higher level of retention of 99mTc-tetrofosmin inside the cells. Ouabain, bumetanide and tetrodotoxin did not show any inhibitory effect on the uptake of 99mTc-tetrofosmin and 99mTc-MIBI, whereas they produced various degrees of inhibition of 201TI uptake. DMA produced approximately 35% inhibition of 99mTc-tetrofosmin uptake and 50% inhibition of 99mTc-MIBI uptake. Nigericin increased the uptake of 99mTc-MIBI by the cells. The addition of CCCP produced the release of 38% of the accumulated 99mTc-tetrofosmin and 52%-70% of the accumulated 99mTc-MIBI, indicating that these percentages of accumulation were related to mitochondrial uptake. Neither Na+-free buffer nor monensin had any significant effect on 99mTc-tetrofosmin accumulation, but they both caused increased accumulation of 99mTc-MIBI. CONCLUSION: The uptake of both 99mTc-tetrofosmin and 99mTc-MIBI through the cell membrane is partly related to the Na+/H+ antiporter system. Only part of the accumulated 99mTc-tetrofosmin inside the cells enters into mitochondria; most of the accumulated 99mc-MIBI is related to mitochondrial uptake. This uptake may be related to Na+.

Parameters of dynamic and static iodine-123-MIBG cardiac imaging.

UNLABELLED: Dynamic and static 123I-MIBG studies were used to investigate various parameters with regard to their usefulness in evaluating cardiac disorders. METHODS: Four patient groups and one control group were included in this study. Dynamic study was acquired immediately after injection at 1 frame/sec for 2 min and at 1 frame/6 sec for the next 30 min using a 64 x 64 matrix format. Static study consisted of planar images at the anterior and left anterior oblique 45 degrees views in a 512 x 512 matrix format for 1 min. The early and delayed planar images were acquired soon after dynamic acquisition and approximately 4 hr after injection, respectively. Net injection dose was calculated as the difference in syringe counts before and after injection. From the dynamic and static studies, the heart uptake ratios at 3 min and 30 min, early uptake ratio and delayed uptake ratio were calculated at various intervals. Early and delayed clearance rates, Ke and Kd, respectively were also determined. These parameters were compared and correlated with each other. RESULTS: Three-minute heart uptake ratios were significantly higher than early or delayed uptake ratios or uptake ratios at 30 min in all groups. All uptake ratios in hemodialysis patients were significantly higher than those in other groups. The Kd values in dilated cardiomyopathy, doxorubicin therapy and vasospastic angina patients were significantly higher than those in hemodialysis patients and normal controls. At least bi-exponential clearance patterns of MIBG from the heart were observed in all groups. CONCLUSION: Three-minute and delayed heart uptake ratios calculated from dynamic and static studies are helpful in elucidating the uptake at nonvesicular sites, which reflect the severity of sympathetic nervous system abnormalities in the heart.

Will thallium-201 replace gallium-67 in salivary gland scintigraphy?

UNLABELLED: We investigated and compared findings on combined 99mTc pertechnetate-201Tl with those of [99mTc]pertechnetate-67Ga scintiscans to elucidate the advantages of 201Tl in detecting various salivary glands disorders. METHODS: We studied 23 patients: 6 had sialadenitis, 12 had benign tumors and 5 had malignant tumors. All but four patients had undergone [99mTc]pertechnetate (before and after lemon stimulation), 201Tl (early and delayed) and 67Ga imaging. RESULTS: Five of six sialadenitis patients showed various degrees of diffuse uptake of 99mTc. All six except one showed early uptake without retention of 201Tl on delayed imaging. The 67Ga scan showed uptake in all patients except one. Nine of 12 benign tumors showed a cold defect on 99mTc scans. Patients with Warthin's tumors and plasmacytoma showed increased 99mTc uptake at the tumor with retention. The 201Tl scan showed early uptake without retention in benign tumors except in three patients, two of whom had Warthin's tumor. Five of the benign tumors, however, were positive on 67Ga scan. None of the malignant tumors showed any uptake of 99mTc. The 201Tl scan showed uptake with tumor retention on delayed images in three patients; three other patients also had positive 67Ga scans. Overall, sensitivity and specificity of 201Tl in detecting malignant tumors were 60% and 73%, respectively, with a negative predictive value of 85%. Sensitivity and specificity for 67Ga were 60% and 47%, respectively, with a negative predictive value of 80%. CONCLUSION: In view of sensitivity, specificity and convenience of 201Tl as well as future prospects for dual-isotope acquisition, 67Ga may be replaced by 201Tl in detecting salivary gland disorder.

Dynamic 99Tcm-ECD SPET correlates well with 201Tl indices in brain tumours.

The dynamic 99Tcm-ethyl cysteinate dimer (99Tcm-ECD) single photon emission tomographic (SPET) characteristics of brain tumours were investigated and compared with 201Tl-chloride SPET indices. Thirty-five patients with histologically confirmed benign and malignant tumours were evaluated using dynamic and standard 99Tcm-ECD. Twenty-eight patients were also examined using standard 201Tl SPET. The following 201Tl indices were calculated: early uptake ratio, delayed uptake ratio, washout rate and retention index. The relationship between uptake of 99Tcm-ECD on dynamic SPET and 201Tl indices was analysed. Nine patients showed positive uptake on dynamic 99Tcm-ECD SPET, all of whom had benign tumours, including five meningothelial meningiomas, three pituitary adenomas of the chromophobe type and one chemodectoma without malignancy. The mean early uptake ratio of the tumours with positive uptake was significantly higher than that of the tumours with negative uptake (17.1 +/- 5.5 vs 9.0 +/- 5.7, P = 0.004). The mean washout rate of the tumours with positive uptake was significantly higher than that of the tumours with negative uptake (61.0 +/- 27.7 vs 0.35 +/- 30.9, P = 0.0004). The mean retention index of the tumours with positive uptake was significantly lower than that of the tumours with negative uptake (0.27 +/- 0.12 vs 0.88 +/- 0.48, P = 0.000006). Only benign tumours showed positive uptake on dynamic 99Tcm-ECD SPET. The 201Tl indices correlated well with the uptake of 99Tcm-ECD on dynamic SPET. The results suggest that dynamic 99Tcm-ECD SPET can identify the benign character of tumours of the brain.

Effects of extracellular Na+ and Ca2+ ions and Ca2+ channel modulators on the cell-associated activity of 99mTc-MIBI and 99mTc-tetrofosmin in tumour cells.

Our aim was to determine whether the Ca2+ ion or cell membrane Ca2+ and Na+/Ca2+ ion transport systems are involved in maintaining the cell-associated activity of technetium-99m-hexakis-methoxy-isobutyl-isonitrile (99mTc-MIBI) and technetium-99m-ethylene-bis[bis(2-ethoxyethyl)phosphin] (99mTc-tetrofosmin) in tumour cell lines. The cell-associated activities of 99mTc-MIBI and 99mTc-tetrofosmin were assessed in various buffers, with or without Na+ and/or with different concentrations of Ca2+, in Lewi's murine lung cell carcinoma and human glioma cell lines. Different Ca2+ channel modulators, such as verapamil, flunarizine and 3,4-dichlorobenzamil (DCB), were used to assess the effect of Ca2+ channels on the cell-associated activity of 99mTc-MIBI and 99mTc-tetrofosmin. Despite significant differences between cell lines, the cell-associated activity of 99mTc-MIBI was higher in buffers without extracellular Ca2+ and Na+. The cell-associated activity of 99mTc-MIBI was significantly lower in all buffers containing high concentrations of Ca2+ in both cell lines. The cell-associated activity of Tc-tetrofosmin was also significantly higher in buffers without Ca2+, and was significantly decreased in buffers with high concentrations of Ca2+. All modulators significantly increased the cell-associated activity of 99mTc-MIBI in both cell lines in all buffers. All modulators increased the cell-associated activity of 99mTc-tetrofosmin, particularly in buffers containing Ca2+. The cell-associated activities of both 99mTc-MIBI and 99mTc-tetrofosmin may be dependent on verapamil-, flunarizine- and DCB-sensitive Ca2+ channels.

Detection of lung and chest tumours using 99Tcm-tetrofosmin: comparison with 201Tl.

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.

Ion transport systems in the uptake of 99Tcm-tetrofosmin, 99Tcm-MIBI and 201Tl in a tumour cell line.

The kinetics, intracellular distribution and effects of ion transport inhibitors on the uptake of 99Tcm-tetrofosmin, 99Tcm-methoxyisobutyl isonitrile (99Tcm-MIBI) and 201Tl were investigated in a tumour cell line. Both uptake and washout of the tracers were measured at specific intervals. Cells were treated with ouabain, dimethyl amiloride (DMA) and bumetanide to observe the effects on uptake, while carbonyl cyanide m-chlorophenylhydrazone (CCCP) was used to study the release of the tracers. The tracers showed similar uptake and washout kinetics. Ouabain inhibited 55-67% of 201Tl, 16-22% of 99Tcm-tetrofosmin and 8-14% of 99Tcm-MIBI. DMA inhibited the uptake of both 99Tcm-tetrofosmin (30%) and 99Tcm-MIBI (21%). Bumetanide stimulated the uptake of 99Tcm-tetrofosmin and 99Tcm-MIBI but inhibited that of 201Tl (37%). When cells were pretreated with various combinations of these ion transport inhibitors, the uptake of 201Tl was related to Na+,K+ pump, Na+,K+, 2Cl- co-transport systems, whereas the uptake of both 99Tcm-tetrofosmin and 99Tcm-MIBI was related to the Na+,K+ pump, Na+/H+ antiport systems. Addition of CCCP released 55% and 90% of accumulated 99Tcm-tetrofosmin and 99Tcm-MIBI respectively, indicating that the percentage released was related to mitochondrial uptake.

Dynamic SPET parameters of 123I-MIBG cardiac imaging.

Early dynamic and late 123I-MIBG SPET studies were performed to investigate several parameters used to distinguish the characteristics of various cardiac disorders. Forty-six individuals (34 non-diabetic, 12 diabetic) with or without heart disease were included in the study. Early dynamic and late static SPET images were acquired using a triple-headed gamma camera. After selecting mid-sections from vertical (VLA) and horizontal (HLA) long-axis images, regions of interest were created over the apex, whole heart and anterior, inferior, septal and lateral walls of the heart. Various uptake ratios at 3, 11 and 19 min and 4 h after injection (HU3, HU11, HU19, DUP) and clearances (Kse: between HU3 and HU11; Ke: between HU11 and HU19; Kd: between HU19 and DUP) were calculated. There were significant differences among various cardiac pathologies on the delayed images. Cardiomyopathy patients showed the lowest uptake on the delayed images. When all segments in normal patients and all involved segments in myocardial infarcted patients were compared, there was significantly lower uptake of MIBG in infarcted segments at all time points. Kd showed the lowest value compared with Kse and Ke. In cardiomyopathy patients, Kse, Ke and Kd were significantly different from each other. Both Kse and Ke were significantly higher in cardiomyopathy patients than in normal patients. In conclusion, the results of this study are in line with published data and precise measurement of uptake and clearance was possible when excluding background and blood pool activity.

Various imaging modalities for the detection of salivary gland lesions: the advantages of 201Tl SPET.

The aim of this study was to compare dual-isotope (99Tc(m) and 201Tl) SPET imaging with computed tomography (CT) and magnetic resonance imaging (MRI) in the differentiation of various lesions of the major salivary glands. Twenty-two patients underwent dual-isotope SPET imaging, of whom 12 also had CT and 15 also had an MRI study. The uptake ratio and retention index for 99Tc(m) and 201Tl were calculated by drawing regions of interest on the involved and normal glands. Both CT and MRI were interpreted by two radiologists. All malignant tumours were detected by all three modalities. Warthin's tumours were detected by dual-isotope SPET imaging; however, MRI failed to differentiate Warthin's tumour from pleomorphic adenoma. Of 13 other benign tumours, dual-isotope SPET correctly diagnosed 12. Of 16 tumours showing a cold defect on the 99Tc(m) images, parametric analysis with 201Tl gave an accuracy of 94%, whereas CT gave an accuracy of 70-90%. MRI was 73-91% accurate in differentiating between benign (Warthin's) and malignant tumours. We believe that dual-isotope SPET imaging (99Tc(m) and 201Tl), together with semi-quantitative analysis, is the method of choice for differentiating between various lesions of the major salivary glands.

Detection of lung lesions and lymph nodes with 201Tl SPET.

The aim of this study was to characterize lung lesions by means of the uptake, retention and washout of 201Tl, and to quantify the sensitivity of 201Tl SPET (single photon emission tomography) in detecting mediastinal and hilar lymph nodes. A total of 68 patients with lung lesions (tumours and inflammation) underwent both helical computed tomography (CT) and 201Tl SPET examinations. Uptake, retention and washout parameters were calculated from early and delayed 201Tl SPET by drawing regions of interest over the primary lesion and the background of the lung. The findings on 201Tl SPET were compared with those on CT and surgical findings. A significant difference in the retention index (RI) was observed between primary malignant and benign lesions. In detecting lymph nodes, the sensitivity, specificity and negative predictive value were 83%, 60% and 90% respectively for early 201Tl SPET, and 50%, 80% and 80% respectively for delayed 201Tl SPET. 201Tl SPET with semi-quantitative analysis, especially RI, helps to differentiate between malignant and benign lung lesions. Lymph nodes larger than 1 cm on CT but not showing 201Tl uptake could be considered non-metastatic lesions.

Uptake and washout of I-123-MIBG in neuronal and non-neuronal sites in rat hearts: relationship to renal clearance.

We investigated the uptake and washout of I-123-metaiodobenzylguanidine (MIBG) in neuronal (both intra- and extravesicular) and non-neuronal sites in the heart and its relationship to renal clearance. Acute renal failure was induced in rats by ligating the renal vessels, and the findings were compared with those of sham-operated rats. Each group consisted of control, reserpine-treated and 6-hydroxydopamine (6-OHDA)-treated subgroups. Rats were sacrificed at 10 minutes and 4 hours after injection of MIBG. MIBG activity was calculated in specimens of heart, spleen, lung and blood. At 10 minutes, no significant difference in MIBG uptake in the heart was observed among the subgroups or between sham-operated and renal failure rats despite a significantly higher blood MIBG activity in the latter. At 4 hours, however, the hearts of both reserpine-treated and 6-OHDA-treated rats showed significantly lower MIBG uptake than control rats. Furthermore, the hearts of renal failure rats showed higher MIBG uptake in the control and reserpine-treated rats than in the corresponding subgroups in sham-operated rats. Intra and extravesicular neuronal uptake of MIBG in the heart were estimated using control, reserpine-treated and 6-OHDA-treated rats. Vesicular uptake values were similar in both the sham-operated group (0.51% ID/g) and the renal failure group (0.44% ID/g). But extravesicular neuronal uptake values were quite different in the renal failure group (0.86% ID/g) and the sham-operated group (0.19% ID/g). In conclusion, uptake to and washout from extravesicular neuronal sites may depend on the concentration of MIBG in the blood or the state of renal clearance, but vesicular uptake may be independent of these factors.

Application of Tc-99m-tetrofosmin as a tumor imaging agent: comparison with Tl-201.

Tc-99m-tetrofosmin SPECT was performed on 6 occasions in 4 patients with hypopharyngeal carcinoma, lung carcinoma, esophageal carcinoma and maxillary plasmocytoma and compared with Tl-201 SPECT. All lesions accumulated both Tc-99m-tetrofosmin and Tl-201. Early uptake ratios of Tc-99m-tetrofosmin were about 2 but those of Tl-201 were much higher (more than 3). Washout rates of Tc-99m-tetrofosmin were higher than those of Tl-201. There was a good positive correlation between the early uptake ratio of Tc-99m-tetrofosmin and that of Tl-201. The delayed uptake ratio and washout rate showed poor correlation. In conclusion, early uptakes of both the agents were similar but their retention patterns were different. Tc-99m-tetrofosmin may be used for tumor imaging though more studies are required to evaluate diagnostic accuracy and the significance of delayed images.

Tl-201 uptake and retention in a Warthin's tumor.

We report scan findings of Tl-201 in a case of histologically proved Warthin's tumor. Dual isotopes acquisition was performed in a case of left parotid Warthin's tumor. Both early and delayed Tc-99m-pertechnetate (Tc-99m) images showed increased uptake at the tumor. Tl-201 scan also showed an increase of uptake on the early image and retention on the delayed image. The uptake ratios of Tl-201 were 3.0 (early) and 2.3 (delayed). Scan findings of Tl-201 in a case of Warthin's tumor were similar to those of Tc-99m, and the interpretation of Tl-201 images should be accompanied with Tc-99m images.

Effects of ion channel modulators in the influx and efflux of Tc-99m-MIBI.

Possible involvement of cell membrane ion transport systems in the uptake and extrusion of Tc-99m-MIBI was investigated by using various buffers with or without Na+ and Ca++, and ion transport inhibitors in a tumor cell line. The ion transport modulators dimethyl amiloride (DMA), verapamil, flunarizine and monensin were used. The uptake of Tc-99m-MIBI was significantly increased in all buffers containing either Na+ or Ca++ alone or none of them. There was significantly increased uptake of Tc-99m-MIBI especially in buffers without Na+. Verapamil, a L-type Ca++ channel blocker, increased Tc-99m-MIBI uptake in all buffers. Flunarizine, which inhibits Na+/ Ca++ channels, caused significantly increased accumulation of Tc-99m-MIBI only in buffer containing both Na+ and Ca++. Monensin, a sodium ionophore, significantly increased uptake of Tc-99m-MIBI. DMA, a potent Na+/H+ antiport inhibitor, significantly inhibited the uptake of Tc-99m-MIBI in all buffers. In conclusion, Tc-99m-MIBI behaves like Na+ during its uptake and extrusion. Extrusion of Tc-99m-MIBI may involve both verapamil- and flunarizine-sensitive pathways.

Incidental detection of breast cancer during T1-201 myocardial SPECT study.

A case of left breast cancer which was detected incidentally by T1-201 SPECT performed to evaluate the status of myocardial perfusion, is reported. Both stress and redistribution T1-201 SPECT clearly delineated the tumor. It was confirmed later as scirrhous carcinoma of the breast.