BACKGROUND: Serum thyroglobulin assays and I-131 imaging and routinely employed for the detection of remaining functioning thyroid tissue after surgery and radioiodine therapy. However, the sensitivity of I-131 is suboptimal resulting in cases of positive thyroglobulin test but negative I-131 imaging, potentially creating a dilemma in subsequent therapeutic management. Other radiopharmaceuticals, such as TI-201 may offer better sensitivity, although it is not clear whether this contributes to the decision-making for subsequent I-131therapy. This prospective cohort study aimed to determine if Tl-201 imaging identified thyroid tissues that will take up therapeutic I-131, and to help define its clinical utility.
METHODS: Fourteen consecutive patients who underwent surgery for well-differentiated thyroid cancer, had I-131 therapy at least eight months previously, and with elevated thyroglobulin (>10 ng/mL) but negative pre-therapy (111 MBq) I-131 whole body scan (WBS), were enrolled in the study. WBS was done using 56.74 MBq of Tl-201. All patients had repeat I-131 ablation (3.7-7.4GBq) one to two months after Tl-201 imaging. Post-therapy WBS was done four to seven days after.
RESULTS: All 14 patients had papillary thyroid carcinoma. Ten patients had a positive Tl-201 scan. Of the 14 subjects, only two had a positive post-therapy I-131 WBS, both whom had a positive Tl-201 scan. Thallium-201 scanning showed a fairly high sensitivity (71%) in demonstrating thyroid remnants or metastases using a thyroglobulin level of >10 ng/mL as standard. However, a positivel Tl-201 scan only has a predictive value of 20% for subsequent uptake of therapeutic I-131 as shown in the post-therapy scan.
CONCLUSION: Thallium-201 uptake correlates poorly with therapeutic I-131 uptake in thyroglobulin-positive, but I-131 scan-negative, differentiated thyroid cancer patients. Results of this study suggest that the presence of thyroid remnants and metastases on Tl-201 imaging is inappropriate as a basis for subsequent I-131 therapy.

Human ; Male ; Female ; Middle Aged ; Adult ; Thyroglobulin ; Thyroid Cancer, Papillary ; Radiopharmaceuticals ; Iodine Radioisotopes ; Thallium ; Thyroid Neoplasms ; Carcinoma ; Neoplasms, Second Primary ; Thallium Radioisotopes

BACKGROUND: Serum thyroglobulin assays and I-131 imaging and routinely employed for the detection of remaining functioning thyroid tissue after surgery and radioiodine therapy. However, the sensitivity of I-131 is suboptimal resulting in cases of positive thyroglobulin test but negative I-131 imaging, potentially creating a dilemma in subsequent therapeutic management. Other radiopharmaceuticals, such as TI-201 may offer better sensitivity, although it is not clear whether this contributes to the decision-making for subsequent I-131therapy. This prospective cohort study aimed to determine if Tl-201 imaging identified thyroid tissues that will take up therapeutic I-131, and to help define its clinical utility.
METHODS: Fourteen consecutive patients who underwent surgery for well-differentiated thyroid cancer, had I-131 therapy at least eight months previously, and with elevated thyroglobulin (>10 ng/mL) but negative pre-therapy (111 MBq) I-131 whole body scan (WBS), were enrolled in the study. WBS was done using 56.74 MBq of Tl-201. All patients had repeat I-131 ablation (3.7-7.4GBq) one to two months after Tl-201 imaging. Post-therapy WBS was done four to seven days after.
RESULTS: All 14 patients had papillary thyroid carcinoma. Ten patients had a positive Tl-201 scan. Of the 14 subjects, only two had a positive post-therapy I-131 WBS, both whom had a positive Tl-201 scan. Thallium-201 scanning showed a fairly high sensitivity (71%) in demonstrating thyroid remnants or metastases using a thyroglobulin level of >10 ng/mL as standard. However, a positivel Tl-201 scan only has a predictive value of 20% for subsequent uptake of therapeutic I-131 as shown in the post-therapy scan.
CONCLUSION: Thallium-201 uptake correlates poorly with therapeutic I-131 uptake in thyroglobulin-positive, but I-131 scan-negative, differentiated thyroid cancer patients. Results of this study suggest that the presence of thyroid remnants and metastases on Tl-201 imaging is inappropriate as a basis for subsequent I-131 therapy.

Human ; Male ; Female ; Middle Aged ; Adult ; Thyroglobulin ; Thyroid Cancer, Papillary ; Radiopharmaceuticals ; Iodine Radioisotopes ; Thallium ; Thyroid Neoplasms ; Carcinoma ; Neoplasms, Second Primary ; Thallium Radioisotopes

BACKGROUND: Coronary microcirculation impairment with sequential decrease in cardiac function is reflected by abnormal left ventricular ejection fraction reserve (LVEFR),which precedes diagnostic evidence of myocardial insult. However, prognostic utility of LVEFR is less, if not least explored. The aim of this study was to evaluate the clinical utility of LVEFR in predicting major cardiac events (MACE) among patients with and suspected coronary artery disease (CAD).
MATERIALS AND METHODS: A retrospective cohort study of 245 patients who underwent stress thallium-201 myocardial perfusion scan (MPS) was conducted. The patients were categorized as having normal or abnormal perfusion scan. Each group was subdivided into normal and abnormal LVEFR groups. All subjects were followed up for any major adverse cardiac events 36 months after MPS through review of hospital records.
RESULTS: There was an overall increase in the likelihood of cardiac events with abnormal LVEFR (i.e., odds ratio of 2.99,p=<0.01). Majority of subjects with abnormal MPS also had abnormal LVEFR showing a significantly lower mean LVEFR (1.17± 7.30 vs. 3.02 ± 7.36p =<0.01).
CONCLUSION: Abnormal LVEFR can be used as an independent predictor of cardiac events which can be observed in subjects with normal and abnormal perfusion scans alike.

Human ; Male ; Female ; Middle Aged ; Adult ; Coronary Artery Disease ; Thallium ; Omega-chloroacetophenone ; Microcirculation ; Stroke Volume ; Heart ; Thallium Radioisotopes ; Myocardium ; Perfusion Imaging

BACKGROUND: Coronary microcirculation impairment with sequential decrease in cardiac function is reflected by abnormal left ventricular ejection fraction reserve (LVEFR),which precedes diagnostic evidence of myocardial insult. However, prognostic utility of LVEFR is less, if not least explored. The aim of this study was to evaluate the clinical utility of LVEFR in predicting major cardiac events (MACE) among patients with and suspected coronary artery disease (CAD).
MATERIALS AND METHODS: A retrospective cohort study of 245 patients who underwent stress thallium-201 myocardial perfusion scan (MPS) was conducted. The patients were categorized as having normal or abnormal perfusion scan. Each group was subdivided into normal and abnormal LVEFR groups. All subjects were followed up for any major adverse cardiac events 36 months after MPS through review of hospital records.
RESULTS: There was an overall increase in the likelihood of cardiac events with abnormal LVEFR (i.e., odds ratio of 2.99,p=<0.01). Majority of subjects with abnormal MPS also had abnormal LVEFR showing a significantly lower mean LVEFR (1.17± 7.30 vs. 3.02 ± 7.36p =<0.01).
CONCLUSION: Abnormal LVEFR can be used as an independent predictor of cardiac events which can be observed in subjects with normal and abnormal perfusion scans alike.

Human ; Male ; Female ; Middle Aged ; Adult ; Coronary Artery Disease ; Thallium ; Omega-chloroacetophenone ; Microcirculation ; Stroke Volume ; Heart ; Thallium Radioisotopes ; Myocardium ; Perfusion Imaging

BACKGROUND: This study was designed to determine the relationship of propranolol pharmacokinetic parameters with portosystemic shunt in CCl4-induced cirrhotic rats. METHODS: Cirrhotic rats(n=6) were induced by intramuscular injection of CCl4 in olive oil(two time per weeks) for 12 weeks. Controls (n=6) were injected intramuscularly with the same dose of olive oil for 12 weeks. We evaluated the amount of portosystemic shunt by thallium-201 per rectal scintigraphy. After intravenous bolus injection of propranolol (2mg/kg) to rats, the serum propranolol concentrations were analyzed by a HPLC-fluorimetric detector system. Pharmacokinetic parameters such as C0, AUC, t(1/2(beta)), and CLp were determined in each group. Then, a small amount of heptic tissue was obtained and subjected to determination of the hepatic collagen content by quantitating 4-hydroxyproline and were inspected by microscope after hematoxylin and eosin stain. RESULTS: In liver biopsy, liver fibrosis progressed in CCl4-induced cirrhotic rats. The serum concentrations of propranolol were significantly (p < 0.01) elevated in CCl4-induced cirrhotic rats. Mean amount of 4-hydroxyproline, mean H/L ratio, and mean AUC in CCl4-induced cirrhotic rats was significantly (p < 0.01) higher than that in control rats. There was a relationship between AUC, H/L ratio, and amount of 4-hydroxyproline. CONCLUSION: H/L ratio may help in the selection of drug dosage (especially blood flow dependent drug) in pre-clinical studies for chronic liver disease during the drug development process.
Animals ; Carbon Tetrachloride Poisoning/*complications ; Chromatography, High Pressure Liquid ; English Abstract ; Liver Cirrhosis, Experimental/*metabolism/physiopathology ; Portal System/physiopathology ; Propranolol/*pharmacokinetics ; Rats ; Rats, Sprague-Dawley ; Thallium Radioisotopes/diagnostic use

OBJECTIVETo investigate the significance of Tl-201 scintigraphy for assessment of neoadjuvant chemotherapy for osteosarcoma.

METHODSThirty-four cases with osteosarcoma were enrolled into this study. The Tl-201 scintigraphy features including uptake ratio(UR) and size ratio(SR) were obtained in both early and delay imaging stages before and after chemotherapy. The responses of chemotherapy were classified into three grades according to the percentage of tumor necrosis in the specimens: necrosis < 50% as grade 1, necrosis of 50% approximately 90% as grade 2, diffuse necrosis > 90% as grade 3. The alteration ratio (AR) and SR were calculated according to tumor necrosis ratio (TNR).

RESULTSOf the 6 patients with grade 1 response, the mean alteration ratios were 3.19% +/- 8.40% and -26.29% +/- 63.61% in early and delay imaging stages, respectively. Among the 18 patients with grade 2 response, the mean alteration ratios were 40.07% +/- 11.95% and 39.30% +/- 9.87%, respectively. Of the 10 patients with grade 3 response, the mean alteration ratios were 78.32% +/- 8.33% and 63.26% +/- 6.06% in early and delay imaging stages, respectively. The results of liner regression analysis of TNR of the surgical specimens showed a significantly positive correlation (r = 0.71) between AR and TNR. The lesion size was reduced in 18 cases, but unchanged in 8 and increased in 8. The liner regression analysis results showed a negative correlation between SR and TNR.

CONCLUSIONThe alteration ratio changes significantly after neoadjuvant chemotherapy and has a significantly positive correlation with tumor necrosis ratio. Thallium-201 scintigraphy is helpful in the evaluation of neoadjuvant chemotherapy for osteosarcoma.

Adolescent ; Adult ; Bone Neoplasms ; diagnostic imaging ; drug therapy ; pathology ; Chemotherapy, Adjuvant ; Child ; Female ; Femoral Neoplasms ; diagnostic imaging ; drug therapy ; pathology ; Humans ; Male ; Neoadjuvant Therapy ; Osteosarcoma ; diagnostic imaging ; drug therapy ; pathology ; Radionuclide Imaging ; Thallium Radioisotopes ; Treatment Outcome ; Tumor Burden ; Young Adult

OBJECTIVETo evaluate the application of ²⁰¹TI and (99m)Tc-MIBI scintigraphy in assessment of neoadjuvant chemotherapy for osteosarcoma.

METHODSTwenty-two patients with osteosarcoma underwent both ²⁰¹TI and (99m)Tc-MIBI scintigraphy. According to tumor necrosis rate (TNR), 22 patients were classified into three groups: Group 1(necrosis less than 50%), Group 2(50% ≊ 89% necrosis) and Group 3(necrosis greater than 90%). The uptake ratio(UR) was obtained in images before and after chemotherapy. The alteration ratio(AR) and tumor necrosis ratio (TNR) were calculated.

RESULTSIn ²⁰¹Tl images,UR(pre) and UR(post) (mean ± s.d.) of Group 1 were 2.14 ± 0.67, 2.07 ± 0.71 (P>0.05); UR(pre) and UR(post)of Group 2 were 3.45 ± 1.57 and 2.02 ± 0.97 (P<0.01); UR(pre) and UR(post) of Group 3 were 3.57 ± 0.67 and 1.36 ± 0.20 (P<0.01). In (99m)Tc-MIBI images, UR(pre)and UR(post) of Group 1 were 1.66 ± 0.42 and 1.85 ± 0.70 (P>0.05); UR(pre) and UR(post) of Group 2 were 2.39 ± 1.41 and 1.68 ± 0.72 (P<0.05);UR(pre) and UR(post) of Group 3 were 2.56 ± 0.60 and 1.19 ± 0.14 (P<0.01). The AR value in (201)Tl scintigraphy was -0.03-0.72, the liner regression analysis of AR versus TNR showed a highly significant positive correlation (r=0.95). The AR value in (99m)Tc-MIBI scintigraphy was -1.21-0.64, the liner regression analysis of AR versus TNR showed a highly significant positive correlation (r=0.71). The liner regression analysis of AR in ²⁰¹TI scintigraphy versus AR in (99m)Tc-MIBI scintigraphy showed a highly significant positive correlation (r=0.70).

CONCLUSIONThe AR changes significantly after neoadjuvant chemotherapy and is positively correlated with TNR, which indicates that ²⁰¹TI- and (99m)Tc-MIBI scintigraphy can be used for evaluation of neoadjuvant chemotherapy.

Adolescent ; Adult ; Bone Neoplasms ; diagnostic imaging ; drug therapy ; Child ; Female ; Humans ; Male ; Neoadjuvant Therapy ; Osteosarcoma ; diagnostic imaging ; drug therapy ; Preoperative Care ; Radionuclide Imaging ; Technetium Tc 99m Sestamibi ; Thallium Radioisotopes ; Young Adult

The aim of the present study was to evaluate the ability of Tl-201 abdominal SPECT to differentiate between chronic focal pancreatitis and pancreatic malignancy. Seventeen patients (12 men, 5 women; mean age, 56 years; 9 pancreatic cancer, 8 chronic pancreatitis) with pancreatic mass were prospectively investigated with Tl-201 abdominal SPECT. In all patients, CT and/or US could not clarify the nature of the pancreatic mass. Focal hot uptake was present in 8 of 9 patients with pancreatic cancer, while it was present in 2 of 8 patients with chronic pancreatitis. Therefore, the sensitivity and specificity of the present study were 89% and 75%, respectively. A significant difference of Tl-201 uptakes was noted between benign and malignant masses (p& 0.05). Therefore, we concluded that Tl-201 abdominal SPECT was a useful test in differentiation of malignant from benign pancreatic mass, especially when the differentiation could not be made by other imaging modalities
Abdomen/*radionuclide imaging ; Chronic Disease ; Diagnosis, Differential ; Evaluation Studies ; Female ; Follow-Up Studies ; Human ; Male ; Middle Age ; Pancreatic Neoplasms/*radionuclide imaging ; Pancreatitis/*radionuclide imaging ; Prospective Studies ; Reproducibility of Results ; Sensitivity and Specificity ; Support, Non-U.S. Gov't ; Thallium Radioisotopes/*diagnostic use ; Tomography, Emission-Computed, Single-Photon/methods

In a patient receiving 5-fluorouracil and levamisole, neurologic deficits suggest the cerebral demyelinating syndrome as a differential diagnosis. The authors report a patient diagnosed as multifocal inflammatory leukoencephalopathy for which thallium-201 ((201)Tl) single photon emission computed tomography (SPECT) and proton magnetic resonance spectroscopy (MRS) were employed as noninvasive diagnostic tools. (201)Tl SPECT study was negative and proton MRS showed an increase of choline and lactate and well preserved N-acetylaspartate. These findings support histopathologic findings of multifocal inflammatory leukoencephalopathy revealing demyelination with relative axonal sparing in the patient.
Adjuvants, Immunologic/adverse effects/therapeutic use ; Antimetabolites, Antineoplastic/adverse effects/therapeutic use ; Aspartic Acid/*analogs & derivatives/metabolism ; Axons/pathology ; Biopsy ; Brain/pathology ; Brain Neoplasms/secondary ; Choline/metabolism ; Colorectal Neoplasms/drug therapy/pathology ; Diagnosis, Differential ; Fluorouracil/adverse effects/therapeutic use ; Human ; Lactic Acid/metabolism ; Leukoencephalopathy, Progressive Multifocal/*diagnosis/etiology ; Levamisole/adverse effects/therapeutic use ; Magnetic Resonance Spectroscopy/*methods ; Male ; Middle Aged ; Neoplasm Metastasis ; Thallium Radioisotopes/*diagnostic use ; Tomography, Emission-Computed, Single-Photon/*methods