Proteomic profiling of microbial transglutaminase-induced polymerization of milk proteins.

Microbial transglutaminase (MTGase)-induced polymerization of individual milk proteins during incubation was investigated using a proteomics-based approach. The addition of MTGase (0.25-2.0 units/mL) caused the milk proteins to polymerize after a 3-h incubation period. Sodium dodecyl sulfate-PAGE analysis showed that the total intensities of the protein bands that corresponded to α(S)-casein, ß-casein, and κ-casein decreased from 8,245.6, 6,677.2, and 586.6 arbitrary units to 1,911.7, 0.0, and 66.2 arbitrary units, respectively. Components with higher molecular weights were observed, and the intensity of these proteins increased after 3h of incubation. These results support that inter- or intramolecular crosslinking occurred in the casein proteins of MTGase-treated milk. Two-dimensional electrophoresis analysis indicated that isomers of ß-casein, κ-casein, a fraction of serum albumin, α(S1)-casein, α(S2)-casein, ß-lactoglobulin, and α-lactalbumin in the milk were polymerized following incubation with MTGase. In addition, MTGase-induced polymerization occurred earlier for ß-casein and κ-casein isomers than for other milk proteins.

Quickly predicting chemotherapy response to paclitaxel-based therapy in non-small cell lung cancer by early technetium-99m methoxyisobutylisonitrile chest single-photon-emission computed tomography.

The purpose of this study was to retrospectively predict the chemotherapy response to paclitaxel in non-small cell lung cancer (NSCLC) using technetium-99m methoxyisobutylisonitrile (Tc-99m MIBI) chest single-photon-emission computed tomography (SPECT) to detect the expression of multidrug-resistance-mediated Mr 170,000 P-glycoprotein. Before chemotherapy with Paclitaxel (Taxol), 30 patients with stage IIIb or IV NSCLC were enrolled in this study. Early chest SPECT 10 min after i.v. injection of Tc-99m MIBI was performed to qualitatively interpret Tc-99m MIBI chest SPECT visually and quantitatively calculate early tumor:normal lung ratios (T:NL) for quick assessment of multidrug-resistant P-glycoprotein expression in NSCLC. On the basis of qualitatively visual interpretation of early Tc-99m MIBI chest SPECT, all of 15 (100%) cases with good response to chemotherapy with Taxol could be detected but 10 (67%) of 15 cases with poor response could not be detected. Early Tc-99m MIBI chest SPECT could correctly predict chemotherapy response in 25 (83%) of 30 of cases. The early T:NL were 3.30 +/- 0.82 for 15 patients with good response and 2.02 +/- 0.19 for 5 patients with poor response. The differences were significant (P < 0.05) by independent Student t tests. However, no significant differences were found for other prognostic factors (age, sex, tumor size, tumor location, stage, and cell type) between good-response and poor-response patients. Early Tc-99m MIBI chest SPECT has the potential to predict chemotherapy response to Paclitaxel.

Detection of esophagitis by 99mTc-methoxyisobutylisonitrile chest SPECT.

UNLABELLED: Esophagitis is a common complication of gastroesophageal reflux disease (GERD). Unfortunately, an accurate diagnosis of esophagitis usually requires invasive endoscopy. The purpose of our study was to evaluate the use of noninvasive 99mTc-methoxyisobutylisonitrile (MIBI) chest SPECT to detect esophagitis in GERD patients. METHODS: Forty GERD patients who underwent endoscopy for diagnosis and grading of esophagitis according to the Savary-Miller grading system were included in this study. 99mTc-MIBI chest SPECT was performed on all patients to detect and grade esophagitis. RESULTS: On the basis of the endoscopic findings, the sensitivity, specificity, and accuracy of 99mTc-MIBI chest SPECT to detect esophagitis were 100%, 77%, and 95%, respectively. The correlation between the Savary-Miller grading system and 99mTc-MIBI chest SPECT grading was found to be good. CONCLUSION: Noninvasive 99mTc-MIBI chest SPECT has excellent sensitivity and good accuracy as a screen for esophagitis.

Effects of 90Y-microspheres on liver tumors: comparison of intratumoral injection method and intra-arterial injection method.

UNLABELLED: Internal radiation therapy using intrahepatic arterial injection of 90Y-labeled glass microspheres (90Y-microspheres) has proven to be a promising therapeutic modality for inoperative liver tumor. Recently, direct intratumoral injection of 90Y-microspheres has been performed with even more encouraging results. The purpose of this study was to compare the treatment efficacy of these 2 methods using 90Y-microspheres. METHODS: Forty-eight male rats, each bearing a hepatic tumor, were divided into 4 groups (12 rats in each group) to evaluate the efficacy of treatment. Group 1 received an intratumoral injection of 37 MBq (1 mCi) 90Y-microspheres. Group 2 received an intratumoral injection of 0.1 mL normal saline as the control group. Group 3 received an intra-arterial injection of 37 MBq (1 mCi) 90Y-microspheres. Group 4 received an intra-arterial injection of 0.1 mL normal saline as the control group. Tumor size was measured by liver sonography before injection as well as at 2 and 4 wk after injection. Survival time was calculated from the day of treatment to 2 mo after treatment by Kaplan-Meier survival analysis. The response rate was evaluated by the change in tumor size and survival time. Fisher's exact, 2-tailed test was used to compare response rates. RESULTS: In the rats treated by intratumoral injection of 90-Y-microspheres, 83.3% (10/12) showed a good response. In contrast, all 12 rats in the control group showed a poor response. The difference was significant (P < 0.00001). Eighty-three percent (10/12) of the rats survived >60 d after intratumoral injection of 90Y-microspheres, whereas only 25% (3/12) of the control rats survived >60 d. The difference was significant (P = 0.0068). In the rats treated by intra-arterial injection of 90Y-microspheres, 58.3% (7/12) showed a good response to the treatment. All rats in the control group showed a poor response. The difference was significant (P = 0.0023). Sixty-six percent (8/12) of the rats survived >60 d after intra-arterial injection of 90Y-microspheres, whereas only 16.7% (2/12) of the control rats survived >60 d. The difference was significant (P = 0.0385). However, the response rate and survival time between the intratumoral treatment group and the intra-arterial treatment group showed no significant difference (P = 0.3707 and 0.3988, respectively). CONCLUSION: Both methods (intratumoral treatment and intraarterial treatment) showed a significantly good response rate and prolonged survival time compared with those of the control groups. However, no significant difference was found in the response rate or survival time between intratumoral treatment and intra-arterial treatment.

Paclitaxel-Based chemotherapy for non-small cell lung cancer: predicting the response with 99mTc-tetrofosmin chest imaging.

UNLABELLED: The purpose of this study was to retrospectively predict the chemotherapeutic response to paclitaxel for non-small cell lung cancer (NSCLC) using 99mTc-tetrofosmin (TF) uptake and to detect the expression of 170-kDa multidrug resistance-mediated P-glycoprotein (MDR-Pgp). METHODS: Before chemotherapy with paclitaxel, 20 patients with stage IIIb or IV NSCLC were enrolled in this study to undergo early and delayed 99mTc-TF chest imaging for calculating tumor-to-normal lung ratios (T/NL) and retention indices (RI) for assessment of the MDR-Pgp in NSCLC. RESULTS: The early and delayed mean T/NLs were 1.59 +/- 0.25 and 1.50 +/- 0.25, respectively, for 10 patients with a good response and 1.09 +/- 0.09 and 1.03 +/- 0.05, respectively, for 10 patients with a poor response. The differences were shown to be significant (P < 0.001) by independent Student t tests. However, no significant differences (P = 0.801) between good-response patients (-5.70% +/- 3.67%) and poor-response patients (-5.23% +/- 4.51%) were found in RI. In addition, other prognostic factors (age, sex, tumor size, stage, and cell type) were not significantly different between good-response patients and poor-response patients. CONCLUSION: 99mTc-TF chest images are potential tools for understanding MDR-Pgp expression in NSCLC and for predicting the chemotherapeutic response to paclitaxel.

Evaluation of regional cerebral blood flow with 99mTc-HMPAO in primary antiphospholipid antibody syndrome.

UNLABELLED: In this study, 99mTc-hexamethyl propyleneamine oxime (HMPAO) SPECT was used to evaluate the regional cerebral blood flow (rCBF) of the brain in patients with primary antiphospholipid antibody syndrome (PAPS). METHODS: Twenty-two women who were PAPS patients, aged 28-60 y, with mild neuropsychiatric manifestations and normal brain MRI findings were enrolled in this study. Brain HMPAO SPECT was performed to detect brain abnormalities. Meanwhile, serum anticardiolipin antibodies (ACA) and lupus anticoagulant (LA) were measured. RESULTS: HMPAO SPECT revealed hypoperfusion lesions in 16 of 22 (73%) PAPS patients. Cerebral cortex and cerebellum were the most and the least commonly involved areas, respectively. Eighteen of 22 (82%) and 14 of 22 (64%) patients had positive ACA and positive LA, respectively. ACA and LA results were related to HMPAO SPECT findings. CONCLUSION: HMPAO SPECT is a sensitive tool for detecting brain abnormalities in PAPS patients with only mild neuropsychiatric manifestations and normal brain MRI findings.

Expression of mediated P-glycoprotein multidrug resistance related to Tc-99m MIBI scintimammography results.

We prospectively studied a total of 24 patients with breast cancer to evaluate the relationship between the degree of accumulation of technetium-99m sestamibi (Tc-99m MIBI) and p-glycoprotein (Pgp) expression in tumor tissues. All 24 patients underwent Tc-99m MIBI scintimammography before surgery or biopsy. Immunohistochemical studies were performed on multiple non-consecutive sections of the same tumor using a Pgp specific monoclonal antibody, JSB-1. Planar images were started 10 min after injection of Tc-99m MIBI. Tumor to background (T/B) ratios calculated from the planar images were correlated with Pgp expression as determined by immunohistochemical studies. The T/B ratios were significantly lower for tumors in eight patients with positive Pgp expression (Group 1) than in 16 patients with negative expression (Group 2) (1.40+/-0.11 and 2.76+/-0.60, P<0. 05). Our data confirmed that Tc-99m MIBI scintimammography is useful for determination of the presence of multidrug resistance due to Pgp expression in patients with breast cancer.

Decreased salivary function in patients with end-stage renal disease requiring hemodialysis.

It has been speculated that impaired salivary flow is common in patients with end-stage renal disease (ESRD) requiring hemodialysis (HD). The aim of this study is to investigate the relation between oral manifestations and salivary function in patients with ESRD undergoing HD. Salivary function was measured by quantitative salivary scintigraphy in 60 patients with ESRD undergoing HD, as well as in 36 age- and sex-matched healthy controls for comparison. The 60 patients with ESRD undergoing HD were separated into two subgroups: group 1, 30 patients with oral manifestations, and group 2, 30 patients without oral manifestations. After an intravenous injection of 5 mCi of technetium 99m pertechnetate, sequential images at 1 minute per frame were acquired for 30 minutes. The 1- and 15-minute uptake ratios were calculated as the tracer uptakes in the four major salivary glands over the background regions of interest. Saliva excretion was stimulated by one 200-mg tablet of ascorbic acid administered orally 15 minutes post-tracer injection, then the maximal excretion ratios of the four major salivary glands were calculated. Our results show significantly poorer salivary function in patients with ESRD with oral manifestations compared with patients with ESRD without oral manifestations and healthy controls by means of objective and quantitative salivary scintigraphy.

Acute paraquat intoxication: using nuclear pulmonary studies to predict patient outcome.

STUDY OBJECTIVES: Paraquat, a widely used herbicide, has been shown to cause severe and often fatal pulmonary fibrosis in humans and laboratory animals. Although paraquat is known to be directly cytotoxic to lung parenchyma, changes in routine lung scintigraphy results after acute paraquat intoxication have not been reported. The objective of this project was to investigate changes in lung ventilation (LV) and alveolar permeability (AP) in patients with paraquat intoxication, using 99mTc diethylenetriamine pentaacetate (DTPA) radioaerosol lung scintigraphy. DESIGN: Prospective, blinded study. SETTING: Nuclear medicine and toxicology departments in two university-affiliated teaching hospitals. PATIENTS OR PARTICIPANTS: Thirteen patients with acute paraquat intoxication were included in this study. Ten volunteers without acute paraquat intoxication were studied for comparison. MEASUREMENTS AND RESULTS: 99mTc DTPA aerosol inhalation and 99mTc macroaggregated albumin (MAA) perfusion lung scintigraphies were performed to determine LV, AP, and lung perfusion (LP). Five of the 13 patients (38%) had significant LV abnormalities; 3 of these 5 patients also showed abnormal LP. Of the 13 patients, 4 patients (31%) showed normal AP and survived. The remaining 9 patients (69%) showed abnormal AP and died. The mean values for AP were statistically different (p < 0.01) between survivor (0.72 +/- 0.16%) and nonsurvivor (1.52 +/- 0.40%) groups. Data from the normal volunteers and survival patients showed a 99mTc clearance slope < 1.00%. Data from patients who died showed a clearance slope > 1.00%. CONCLUSION: These results indicate that AP, measured by 99mTc DTPA aerosol inhalation lung scintigraphy, may help predict outcome in patients with paraquat intoxication.

A comprehensive study on the blockage of thyroid and gastric uptakes of 188Re-perrhenate in endovascular irradiation using liquid-filled balloon to prevent restenosis.

188Re-perrhenate has been reported effective in preventing restenosis after percutaneous transluminal coronary angioplasty. However, if the balloon ruptures, 188Re-perrhenate is released into the circulation, causing high radiation dosing to the thyroid and stomach. In this study, we evaluated the effects of perchlorate or iodide given at different times and in different ways for blocking the uptake of 188Re-perrhenate in the thyroid glands and the stomach to find the best method to apply clinically to reduce the radiation dose in case of balloon rupture. Sodium perchlorate, sodium iodide, or potassium iodide was given orally or intravenously to rats before, during, and after the injection of 188Re-perrhenate. The rats were sacrificed and we calculated the concentration of 188Re-perrhenate in various organs to evaluate the preblocking, mixed formula, and postblocking effects of perchlorate or iodide. Our data showed that the preblocking method effectively reduced the uptake of 188Re-perrhenate in both the thyroid and the stomach. The mixed formula method also demonstrated good blocking effect. The postblocking method showed obvious depression of thyroid uptake of perrhenate but its blocking effect on the stomach was not satisfactory.

Effect of reaction conditions on preparations of rhenium-188 hydroxyethylidene diphosphonate complexes.

Rhenium-186 (Re-186) hydroxyethylidene diphosphonate (HEDP) has been shown to localize in metastatic foci within bone in a manner similar to Tc-99m bone-seeking agents. Usually, in the preparation of diagnostic Tc-99m radiopharmaceuticals, the concentration of Tc is at trace level (10(-8) M). However, large amounts of carrier are included in the preparation of Re-186 radiopharmaceuticals (10(-4) M), which may significantly affect the preparation of Re-HEDP. In this study, Re-188 was used as an Re tracer. The effects of pH and concentrations of Re carrier on the preparation of Re-HEDP were investigated. Re-188-Sn-HEDP was prepared by reconstitution of a kit of lyophilized HEDP mixture, and tin chloride with a radioactive solution of perrhenate in saline. The total concentration of Re present in this work ranged from 10(-8) to 10(-3) M. The results showed that high labeling efficiency was obtained for each preparation. Although the chemical behaviors of the Re-188 HEDP complexes, with and without carrier, were similar, the biodistribution patterns of carrier free Re-188 HEDP in rats were found to differ from the biodistribution patterns of carrier-added Re-188 HEDP.

Rhenium-188-Labeled DTPA: a new radiopharmaceutical for intravascular radiation therapy.

Balloon angioplasty is a standard treatment for artherosclerotic coronary artery disease. However, its clinical value is reduced by a high restenosis rate. A new concept in preventing restenosis is the use of a liquid-filled balloon containing a beta-emitting radioisotope. In this study, we performed biodistribution studies of Re-188 perrhenate and Re-188 diethylenetriaminopentaacetate (DTPA) to assess the resulting organ dose values in the event of balloon rupture if these agents are used for the clinical inhibition of restenosis after percutaneous transluminal coronary angioplasty (PTCA). After injecting Re-188 preparations intravenously, rats were killed at 10 min, 30 min, 60 min, 2 h, and 6 h (n = 5 per group). Tissue concentrations were calculated and expressed as percent injected dose per gram or per milliliter (%ID/g or %ID/mL). In addition, urine excretion and thyroid gland uptake were evaluated in rats (n = 5 per group) with a gamma camera after administration of 37 MBq (1 mCi) of each agent. Our data showed that both agents were excreted primarily via urine. However, the excretion of Re-188 DTPA was much faster than that of Re-188 perrhenate via the urinary system. The biodistribution data revealed that radioactivity levels in the stomach and the thyroid gland were high in the perrhenate group but low in the Re-188 DTPA group. The concentration levels in other tissues including lung, liver, testis, muscle, and blood were low throughout this study for both agents. The thyroid radiation value in the Re-188 perrhenate group was 0.163 mGy/MBq, which was much higher than that of the Re-188 DTPA group (0.0167 mGy/MBq). The stomach radiation value was as high as 0.127 mGy/MBq for Re-188 perrhenate, compared with 0.013 mGy/MBq for Re-188 DTPA. In conclusion, in the event of balloon rupture, the release of Re-188 DTPA results in lower radiation doses than Re-188 perrhenate, especially to the thyroid gland and the stomach. Our data suggest that Re-188 DTPA is a useful radiopharmaceutical for endovascular irradiation.

Comparison of various rhenium-188-labeled diphosphonates for the treatment of bone metastases.

In the past, many diphosphonates were introduced as bone scan radiopharmaceuticals. In addition, diphosphonates have been labeled with beta-emitted isotopes and developed into useful therapeutic drugs for bone metastases. However, it is not clear which diphosphonate is the best choice when labeling with Re-188. In this study, we labeled methylene diphosphonate (MDP), hydroxyethylidene diphosphonate (HEDP), and hydroxymethane diphosphonate (HDP) with Re-188. Each radiopharmaceutical was further evaluated in two conditions (with and without carrier). Twenty-four rabbits were used (four in each group) for the analysis of the biodistributions and bone uptakes of these radiopharmaceuticals to assess their potential for clinical applicability. Four hours after intravenous injection of approximately 37 MBq (1 mCi) Re-188-labeled diphosphonate preparations, whole body scans were performed using a large-field gamma camera equipped with a high resolution collimator. Bone-to-soft tissue ratios (B/S ratio) were calculated using a computer program. Our data showed that Re-188 HEDP with carrier (10(-4) M carrier) could accumulate in the skeletal system whereas very little absorption by bone was observed in the rabbits that were injected with carrier-free Re-188 HEDP. In addition, no significant bone uptake was demonstrated for Re-188 MDP or Re-188 HDP, with or without carrier. The B/S ratio was 25.06 in the Re-188 HEDP with carrier group but less than 3 in the other groups. In conclusion, HEDP is the best choice among these three bone-seeking drugs when labeled with Re-188. But, it is necessary to add carrier when preparing Re-188 HEDP for the treatment of bone metastases.

The role of technetium-99m methoxyisobutylisonitrile scintimammography in diagnosis of breast cancer in patients with mammographically dense breasts.

The purpose of this study was to assess the contribution of techentium-99m methoxyisobutylisonitrile (Tc-99m sestamibi) scintimammography in the diagnosis of breast cancer in 32 female patients with indeterminate mammographic probability of malignancy because of mammographically dense breasts. All the breast masses were removed and histopathological diagnoses were obtained in all cases. The results showed that scintimammography with Tc-99m sestamibi was positive in 21 patients (20 true-positive, 4 false-positive) and negative in 11 patients (7 true-negative, 4 false-negative). The diagnostic sensitivity, specificity and accuracy rates were 83%, 88% and 84%, respectively, in the differentiation of malignant from benign breast masses in the patients with mammographically dense breasts. The detection of malignant breast tumors by Tc-99m sestamibi scintimammography was independent of the density of the breast tissue. In conclusion, Tc-99m sestamibi scintimammography appears to be a useful diagnostic method for the detection of breast cancer in patients with non-diagnostic mammograms because of mammographically dense breasts.

Tissue polypeptide specific antigen (TPS) as a tumor marker in nasopharyngeal carcinoma.

Tissue polypeptide specific antigen (TPS) is a new tumor marker that indicates tumor proliferative rate rather than tumor burden. The purpose of this study is to assess the clinical value of TPS in patients with nasopharyngeal carcinoma (NPC). Serum levels of TPS were measured in 60 patients with untreated NPC including 36 squamous cell carcinomas (SCC) and 24 undifferentiated carcinomas. NPC patients were separated into different subgroups based on the International Union Against Cancer (UICC) TNM classification system. Forty three healthy subjects without any evidence of malignancy or other systemic diseases were included as controls. The results showed that (1) the mean serum TPS level of the NPC patients was significantly higher than that of the healthy controls, (2) the mean serum TPS level of NPC patients with SCC was significantly higher than patients with undifferentiated carcinomas, (3) the mean serum TPS levels of NPC patients with higher TNM stages were significantly higher than those with lower TNM stages, (4) the overall diagnostic sensitivity of TPS for NPC is 58.3%, and (5) the overall diagnostic sensitivities of TPS in NPC patients with undifferentiated carcinomas and higher TNM stages were significantly higher than those with SCC and lower TNM stages. In conclusion, our results suggest that TPS may have a potential clinical role as a valuable tumor marker for NPC.

Cytokeratin fragment 19 (CYFRA 21-1) in healthy smokers.

Two hundred and ninety-three normal female non-smokers, 268 normal male non-smokers, and 224 normal male smokers were included in our comparative study to determine possible effect of smoking on the serum levels of cytokeratin fragment 19 (CYFRA 21-1). Immunoradiometric assay (IRMA) was used, and the results revealed that the mean +/- SD CYFRA 21-1 levels in the 293 normal female non-smokers, 268 normal male non-smokers, and 224 normal male smokers were 1.28 +/- 0.82, 1.38 +/- 0.74, and 1.47 +/- 0.62 ng/ml, respectively. There is no significantly statistical difference in the CYFRA 21-1 level among the three groups. In conclusion, we suggest that smoking has no effect on the serum levels of CYFRA 21-1.

Technetium-99m tetrofosmin mammoscintigraphy findings related to the expression of P-glycoprotein mediated multidrug resistance.

We studied 30 patients with infiltrating ductal breast carcinomas to evaluate the relationship between the degree of accumulation of technetium-99m tetrofosmin (Tc-TETRO) and p-glycoprotein (Pgp) expression in breast tumor tissues. All of the 30 patients underwent Tc-TETRO mammoscintigraphy to calculate breast tumor uptake of Tc-TETRO to background (T/B) ratios before surgery or biopsy. Immunohistochemical analysis was performed to determine Pgp expression in the pathological specimens of the 30 breast tumors. The T/B ratios were significantly lower for tumors in 12 patients with positive Pgp expression (Group A) than for those in 18 patients with negative expression (Group B) (1.20 +/- 0.12 and 1.94 +/- 0.30, p < 0.05). Our results supported the opinion that Tc-TETRO mammoscintigraphy is helpful for determining in vivo the presence of multidrug resistance due to Pgp expression in breast carcinoma patients.

Expression of drug resistance protein related to Tc-99m MIBI breast imaging.

Adjuvant and neoadjuvant chemotherapy is increasingly being used in the treatment of breast cancer patients. However, drug resistance plays an important role in chemotherapy failure in this cancer. The aim of this study was to determine the correlation between technetium-99m sestamibi (Tc-99m MIBI) breast imaging results and expression of the drug resistance proteins (p-glycoprotein (Pgp), Ki-67 and mutant p53) in human breast cancer tissues. Twenty-four breast cancer patients underwent Tc-99m MIBI breast imaging before surgery or biopsy. Protein expression was investigated by immunohistochemical studies on multiple nonconsecutive sections of surgery or biopsy samples. Tumor to background (T/B) ratios calculated by Tc-99m MIBI breast imaging were correlated with protein expression determined by immunohistochemical studies. The T/B ratios were significantly lower in 8 patients with positive Pgp expression (Group 1) when compared with 16 patients with negative Pgp expression (Group 2) (1.40 +/- 0.11 and 2.76 +/- 0.60, p < 0.05). However, the differences of T/B ratios between the patients with positive and negative Ki-67 mutant p53 expression were not significant. Our data confirmed that Tc-99m MIBI breast imaging is useful for determination of the presence of Pgp expression in breast cancer patients. No significant relationship between Tc-99m MIBI breast imaging results and Ki67/mutant p53 was found.

Usefulness of technetium-99m tetrofosmin mammoscintigraphy as compared to mammography for detecting and differentiating palpable breast masses of young Taiwanese women.

Sixty young Taiwanese women with palpable breast masses detected by mammography and/or physical examinations underwent technetium-99m tetrofosmin (Tc-TETRO) mammoscintigraphy to assess its value for detecting and differentiating breast masses. The results showed that 42 of the 45 cases of breast carcinoma were detected by Tc-TETRO mammoscintigraphy. Fourteen of the 15 o benign breast lesions were differentiated by Tc-TETRO mammoscintigraphy. The diagnostic sensitivity, specificity, positive predictive value negative predictive value and accuracy of Tc-TETRO mammoscintigraphy were 93% 93% 98% 82% and 93% respectively. Thirty-eight of the 45 cases of breast carcinoma were detected by mammography. Twelve of the 15 of benign breast lesions were differentiated by mammography. The diagnostic sensitivity, specificity, positive predictive value, negative predictive value and accuracy of mammography were 84% 80% 93% 63% and 83% respectively. We concluded that Tc-TETRO mammoscintigraphy when compared to mammography significantly improves the accuracy of detection and differentiation of breast cancer in Taiwanese women.

Comparison and discrepancy of 18F-2-deoxyglucose positron emission tomography and Tc-99m MDP bone scan to detect bone metastases.

The purpose of this study was to evaluate the usefulness of positron emission tomography with 18F-2-deoxyglucose (FDG-PET) for the detection of malignant bone metastases, and to compare FDG-PET results with conventional technetium-99m methylene diophosphate (Tc-99m MDP) bone scan findings. Twenty-four patients (10 females, 14 males, ages: 39-71 years) with biopsy-proven malignancy and suspected bone metastases, underwent whole body FDG-PET and bone scan to detect bone metastases. Bone metastases were established in 39 discordant bone lesions by histopathological examination of biopsy samples, MRI/CT, and follow-up bone scan/FDG-PET findings showing progressively and extensively widespread bone lesions. A total of 98 bone lesions found on either FDG-PET or bone scan were evaluated For 39 bone lesions with discordant findings between FDG-PET and bone scan, histopathological examination, MRI/CT and follow-up bone scan/FDG-PET findings revealed 8 metastatic and 0 benign bone lesions with positive FDG-PET findings, not detected on bone scan. Eleven metastatic and 20 benign bone lesions with positive bone scan findings were not detected on FDG-PET. FDG-PET has a better specificity, but a lower sensitivity for detecting malignant bone metastases when compared with bone scan.