Sentinel node detection with radiocolloid lymphatic mapping in early invasive cervical cancer

We assessed the feasibility of sentinel lymph node detection using technicium-99 radiocolloid lymphatic mapping for predicting lymph node metastases in early invasive cervical cancer. Thirty patients with cervical cancer (stages IA2-IIA) underwent preoperative lymphoscintigraphy using technicium-99 intracervical injection and intraoperative lymphatic mapping with a handheld gamma probe. After dissection of the sentinel nodes, the standard procedure of pelvic lymph node dissection and radical hysterectomy was performed as usual. The sentinel node detection rate was 100% (30/30). There were seven (23.3%) cases of microscopic lymph node metastases on pathologic analysis. All of them had sentinel node involvement. Therefore, the sensitivity of sentinel node identification for prediction of lymph node metastases was 100%, and no false negative was found. Preoperative lymphoscintigraphy, coupled with intraoperative lymphatic mapping, located the sentinel nodes accurately in our study patients. This sentinel node detection method appears to be feasible for predicting lymph node metastases.

Sentinel node detection with radiocolloid lymphatic mapping in early invasive cervical cancer

We assessed the feasibility of sentinel lymph node detection using technicium-99 radiocolloid lymphatic mapping for predicting lymph node metastases in early invasive cervical cancer. Thirty patients with cervical cancer (stages IA2–IIA) underwent preoperative lymphoscintigraphy using technicium-99 intracervical injection and intraoperative lymphatic mapping with a handheld gamma probe. After dissection of the sentinel nodes, the standard procedure of pelvic lymph node dissection and radical hysterectomy was performed as usual. The sentinel node detection rate was 100% (30/30). There were seven (23.3%) cases of microscopic lymph node metastases on pathologic analysis. All of them had sentinel node involvement. Therefore, the sensitivity of sentinel node identification for prediction of lymph node metastases was 100%, and no false negative was found. Preoperative lymphoscintigraphy, coupled with intraoperative lymphatic mapping, located the sentinel nodes accurately in our study patients. This sentinel node detection method appears to be feasible for predicting lymph node metastases

Comparison of CYFRA 21-1 and squamous cell carcinoma antigen in detecting nasopharyngeal carcinoma

CYFRA 21-1 is a newly developed tumor marker that is especially useful for detecting squamous cell carcinoma (SCC) of the lung. Squamous cell carcinoma antigen is a proven tumor marker that is especially useful for detecting SCC of the cervix. Our aim in this study was to compare the clinical value of CYFRA 21-1 and SCC antigen in the detection of nasopharyngeal carcinoma (NPC). Serum levels of CYFRA 21-1 and SCC antigen were measured in 80 untreated NPC patients and 77 healthy controls. The cutoff values of CYFRA 21-1 and SCC antigen, determined at the 95th percentile of the 77 healthy controls, were 2.48 ng/mL and 1.49 ng/mL, respectively. The results revealed that the mean serum value of only CYFRA 21-1 was significantly higher in the 80 NPC patients than in the 77 healthy controls, and the detection sensitivity of CYFRA 21-1 for NPC was significantly higher than that of SCC antigen. In conclusion, our results suggest that CYFRA 21-1 is a better tumor marker than SCC antigen for detection of NPC.

Effect of imaging time on gallium renal scan

AIM

Gallium renal imaging has been reported to be useful in monitoring disease activity and predicting the response to therapy in lupus nephritis. Gallium renal images are usually obtained 48 h after the injection of 67Ga citrate, but 72-h images sometimes are the only available pictures. The aim of the present study was to determine whether the time intervals from injection to imaging had any effect on the grading of gallium renal scintigraphy.

METHODS

Fifty-five patients with lupus nephritis underwent gallium renal imaging at both 48 h and 72 h post-injection of 111 MBq of 67Ga citrate. The relative uptakes of 67Ga by the kidneys and the spine was judged visually on the analog images. Renal uptake was rated on a scale of 0-3.

RESULTS

Fifty-three patients (96.3%) had the same grading of renal uptake in the 48-h and the 72-h images. Only two patients (3.7%) had a different grading in the 72-h images when compared to the 48-h images. The correlation between the 48-h renal uptake and 72-h renal uptake was excellent, with a Spearman R value of 0.94. No significant difference was noted between these two groups, with a P value of 0.76 (using a Wilcoxon matched pairs test).

CONCLUSION

A gallium renal scan can be obtained either 48 h or 72 h after injecting 67Ga citrate. The imaging time did not interfere with the grading of renal uptake in lupus nephritis.

Intra-tumoural injection of 90Y microspheres into an animal model of hepatoma

BACKGROUND

Intrahepatic arterial injection of 90Y glass microspheres (90Y microspheres) is a useful therapeutic modality for inoperative liver tumour. Recently, a new concept of interstitial radiotherapy in the treatment of hepatic malignancies has been carried out with even more encouraging results. However, information regarding this technique is still very rare. The purpose of this study was to analyse the kinetics and biodistribution of 90Y microspheres in rats with hepatic tumours following intra-tumoural injection.

METHODS

Twenty male Sprague-Dawley rats with hepatoma were killed at 1 h, 24 h, 48 h and 72 h (five rats each time) after intra-tumoural injection of approximately 7.4 MBq of 90Y microspheres. Samples of various organs were obtained and used to calculate the tissue concentrations and radiation doses.

RESULTS

Our data showed that the radioactivity in the tumour was very high throughout this study. The lung was the only organ other than the tumour which showed high radioactivity. The concentrations of radioactivity in other organs, such as normal liver, muscle, spleen, bone, testis, and whole blood were quite low throughout the study.

CONCLUSION

Direct intra-tumoural injection of 90Y microspheres is extremely attractive as a clinical therapeutic alternative in hepatoma patients.

Quantifying the dietary potassium requirement of juvenile hybrid tilapia (Oreochromis niloticus x O. aureus)

An 8 week feeding trial was conducted to determine the dietary K requirement for juvenile hybrid tilapia (Oreochromis niloticus x O. aureus). Purified diets with eight levels (0, 1, 2, 3, 4, 5, 7, 10 g/kg diet) of supplemental K were fed to tilapia. Each diet was fed to three replicate groups of fish initially weighing a mean value of 0.77 (SE 0.01) g/fish in a closed, recirculating rearing system. Weight gain was higher (P < 0.05) in fish fed the diets supplemented with 2, 3 and 4 g K/kg diet than in fish fed diet with 10 g K/kg diet and the unsupplemented control diet. Gill Na+-K+ ATPase activity was highest in fish fed the diets supplemented with 1-3 g K/kg diet, followed by fish fed the diet with 5 g K/kg diet and lowest in fish fed the diet with 10 g K/kg diet. Whole-body K content in fish were generally increased as the dietary K supplementation level increased. Analysis by polynomial regression of weight gain and gill Na+-K+ ATPase activity and by linear regression of whole-body K retention of the fish indicated that the adequate dietary K concentration for tilapia is about 2-3 g/kg diet.

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

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.

Tissue polypeptide-specific antigen and carcinoembryonic antigen for early prediction of recurrence in lung adenocarcinoma

Fifty patients with lung adenocarcinoma, including 20 cases with recurrence and 30 cases without recurrence 1 year after operation, were enrolled in this study. The serial serum levels of tissue polypeptide-specific antigen (TPS) and carcinoembryonic antigen (CEA) were measured before operation and at 1 week, and at 1, 3, 6, 9, and 12 months after operation for early detection of recurrence. The results revealed that: 1) mean serum values of TPS were significantly higher at 1, 3, 6, 9, and 12 months after operation in 20 patients with recurrent adenocarcinoma, when compared with 30 patients without recurrent adenocarcinoma; 2) mean serum values of CEA were significantly higher at 9 months and 12 months after operation in 20 patients with recurrent adenocarcinoma, when compared with 30 patients without recurrent adenocarcinoma. We conclude that TPS is a better marker than CEA for early prediction of adenocarcinoma recurrence in lung within 1 year after operation. However, a longer follow-up study should be encouraged.

Detection of esophagitis by 99mTc-methoxyisobutylisonitrile chest SPECT

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.

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.

Comparison of 18-fluoro-2-deoxyglucose positron emission tomography and computed tomography in detection of cervical lymph node metastases of nasopharyngeal carcinoma

Neck lymph nodes (LNs) from 18 patients with nasopharyngeal carcinoma (NPC) were evaluated with 18-fluoro-2-deoxyglucose positron emission tomography (FDG-PET). Eighteen NPC patients underwent head and neck FDG-PET and computed tomography (CT) for detection of suspected neck LN metastases. For final diagnosis, biopsies were taken from neck LNs with discordant findings between FDG-PET and CT. Meanwhile, standard uptake values (SUVs) of the FDG-PET images were calculated to differentiate metastatic LNs from benign LNs. A total of 90 neck LNs found on either FDG-PET or CT were evaluated. In addition to 27 concordant positive results and 42 concordant negative LN results, biopsy findings revealed 11 metastatic LNs that were detected by FDG-PET but not by CT. However, the SUVs of the 11 metastatic LNs and 7 benign LNs were not significantly different. The CT scanning showed positive findings for I metastatic LN with negative FDG-PET findings. In addition, the tumor stage was upgraded in 5 patients on the basis of FDG-PET findings. In comparison with CT, FDG-PET has a higher potential for detecting neck LN metastases of NPC and assessing NPC tumor stage.

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

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.

The role of rhinoscintigraphy in the evaluation of nasal mucociliary clearance function in patients with sinusitis

Nasal mucociliary clearance is one of the homeostatic systems of the respiratory mucosa. Various rhinopathic conditions may involve alterations in nasal mucociliary clearance. The aim of this study was to assess the clinical role of rhinoscintigraphy in the evaluation of nasal mucociliary clearance function of sinusitis patients in comparison with a healthy control group. A single droplet of 99Tcm-labelled macroaggregated albumin (99Tcm-MAA) was deposited on the floor of the nasal meatus about 1 cm behind the mucocutaneous junction, and its course was followed with a gamma camera. The nasal mucociliary clearance was presented as the velocity (mm x min(-1)) of nasal mucociliary transport of the 99Tcm-MAA droplet. A significant difference in nasal mucociliary clearance was observed between the two groups, with a mean of 4.28+/-1.38 mm x min(-1) (4.3+/-1.35 mm x min(-1) in the right nostril, 4.27+/-1.42 mm x min(-1) in the left nostril) for the controls; and 1.8+/-0.64 mm x min(-1) (1.79+/-0.65 mm x min(-1) in the right nostril, 1.82+/-0.63 mm x min(-1) in the left nostril) for the patients with sinusitis. Rhinoscintigraphy is a safe, easy, quick and reliable imaging method for evaluating the ciliary activity of nasal mucosa and the nasal mucociliary clearance function in patients with sinusitis.

Does bowel preparation improve the quality of abdominal gallium scintigraphy?

Physiological accumulation of gallium in the intestine is a major weakness of gallium scintigraphy in evaluating the abdomen. In this study, we used two different cathartics to evaluate the efficacy of bowel cleansing in improving the quality of abdominal gallium imaging. One hundred and fifty patients underwent gallium scintigraphy and were randomly divided into three groups. Group A received no bowel preparation, Group B received 30 ml of castor oil the night before imaging, and Group C received bisacodyl the night before imaging. Gallium activity in the intestine was rated on a three-point scale from 0 to II based on the anterior view of a delayed 48-h gallium image. Our data showed that the incidence of gallium accumulation in the small intestine was low. On the contrary, there was high prevalence of gallium activity in the colon. Forty-eight percent of Group A patients had obvious gallium activity in the colon. The percentage decreased significantly to 28% and 22% in Groups B and C, respectively. No significant difference was noted between Group B and Group C. In conclusion, our data suggest that the application of either castor oil or bisacodyl significantly improves the quality of 48-h abdominal gallium scintigraphy. There were no significant differences in the efficacy of bowel cleansing on gallium activity between these two laxatives.

Semi-quantitative evaluation of gallium-67 scintigraphy in lupus nephritis

Within nuclear medicine there is a trend towards quantitative analysis. Gallium renal scan has been reported to be useful in monitoring the disease activity of lupus nephritis. However, only visual interpretation using a four-grade scale has been performed in previous studies, and this method is not sensitive enough for follow-up. In this study, we developed a semi-quantitative method for gallium renal scintigraphy to find a potential parameter for the evaluation of lupus nephritis. Forty-eight patients with lupus nephritis underwent renal biopsy to determine World Health Organization classification, activity index (AI) and chronicity index (CI). A delayed 48-h gallium scan was also performed and interpreted by visual and semi-quantitative methods. For semi-quantitative analysis of the gallium uptake in both kidneys, regions of interest (ROIs) were drawn over both kidneys, the right forearm and the adjacent spine. The uptake ratios between these ROIs were calculated and expressed as the "kidney/spine ratio (K/S ratio)" or the "kidney/arm ratio (K/A ratio)". Spearman's rank correlation test and Mann-Whitney U test were used for statistical analysis. Our data showed a good correlation between the semi-quantitative gallium scan and the results of visual interpretation. K/S ratios showed a better correlation with AI than did K/A ratios. Furthermore, the left K/S ratio displayed a better correlation with AI than did the right K/S ratio. In contrast, CI did not correlate well with the results of semi-quantitative gallium scan. In conclusion, semi-quantitative gallium renal scan is easy to perform and shows a good correlation with the results of visual interpretation and renal biopsy. The left K/S ratio from semi-quantitative renal gallium scintigraphy displays the best correlation with AI and is a useful parameter in evaluating the disease activity in lupus nephritis.

Beta-2-microglobulin (beta 2M) as a tumor marker in nasopharyngeal carcinoma

The purpose of this study was to assess the clinical value of serum beta-2-microglobulin (beta 2M) in patients with nasopharyngeal carcinoma (NPC). beta 2M levels were assayed in 145 Taiwanese patients with untreated NPC, including 100 squamous cell carcinomas (SCC) and 45 undifferentiated carcinomas. The 145 NPC patients were separated into different subgroups based on the International Union Against Cancer (UICC) TNM classification system. In addition, 50 healthy subjects without any evidence of malignancy or other systemic diseases were included as controls. The results showed that (1) the mean serum, beta 2M level of the 145 NPC patients was higher than that of the 50 healthy controls and (2) the mean serum beta 2M levels of NPC patients who were male, older, with SCC, with higher TNM stages, and with a shorter survival time were higher than those patients who were female, younger, with undifferentiated carcinomas, with lower TNM stages, and with a longer survival time. However, none of the differences were significant. In addition, the overall detecting sensitivity of beta 2M for NPC was only 24.1%, and the detecting sensitivities in NPC patients who were male, older, with SCC, with higher TNM stages, and with a shorter survival time were higher than those of patients who were female, younger, with undifferentiated carcinomas, with lower TNM stages, and with a longer survival time. However, these differences also were not significant. In conclusion, our results suggest the beta 2M may have limited clinical potential as a valuable tumor marker for NPC.

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.

Evidence of abnormal esophageal motility in syndrome X by radionuclide esophageal transit test

In 30 patients with syndrome X, esophageal motility was evaluated by radionuclide esophageal transit test (RETT). Esophageal motility measurements included esophageal mean transit time (MTT), residual fraction (RF), and retrograde index (RI). In comparison with 25 age- and sex-matched healthy volunteers, 66% of the patients with syndrome X had abnormal RETT findings including 50% of cases with longer MTT, 50% of cases with higher RF, and 33% of cases with higher RI. In addition, the mean values of MTT, RF, and RI in patients with syndrome X were significantly higher than those of healthy volunteers. We conclude that abnormal esophageal motility occurred in a large portion of syndrome X patients based on an simple and noninvasive RETT.

Technetium-99m methoxy-isobutyl-isonitrile chest single photon emission computed tomography to detect mediastinal lymph node metastasis in patients with non-small cell lung cancer: comparison with computed tomography

This study evaluated the clinical role of Tc-99m-methoxyisobtylisonitrile (Tc-MIBI) single photon emission computed tomography (SPECT) of the chest in the detection of mediastinal lymph node (MLN) metastasis in patients with non-small cell lung cancer (NSCLC). Twenty-five patients with proven NSCLC were enrolled in this study. Each of the patients received computed tomography (CT) of the chest and Tc-MIBI SPECT of the chest for presurgical staging. A postsurgical pathologic diagnosis was made and these patients were evaluated for the study of mediastinal lymph nde (MLN) involvement. Meanwhile, 10 volunteers also accepted Tc-MIBI SPECT of the chest for comparison. The results showed that the diagnostic sensitivity, specificity and accuracy of Tc-MIBI chest SPECT were 81.8%, 85.7% and 84% and for chest CT they are 36.3%, 85.7% and 64%, respectively. Our results indicated that Tc-MIBI chest SPECT was more sensitive and accurate than chest CT in the evaluation and detection of MLN involvement in the NSCLC patients.

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.

Detection of esophageal carcinoma using single photon emission computed tomography with technetium-99m tetrofosmin

Technetium-99m tetrofosmin (Tc-TF) a thallium-201 (Tl-201) and technetium-99m methoxy-isobutyl-isonitrile (Tc-MIBI) competitor, being used as a new radiopharmaceuticalfor myocardial imaging was assessed to understand its value in detecting esophageal carcinoma (Eso-Ca). Forty patients with Eso-Ca underwent Tc-TF single photon emission computed tomography (SPECT) of the chest. Meanwhile 15 controls also accepted Tc-TF SPECT of the chest for comparison. Among the 40 patients Tc-TF chest SPFCT detected Eso-Ca in 33 (82.5%) but not in 7 (17.5%). In contrast all 15 normal controls (100.0%) had negative Tc-TF chest SPECT Detection sensitivities were higher for tumors located in the middle portion of the esophagus for epidermoid ca and for tumors with poor differentiation when compared with tumors in the upper or lower portion for adenocarcinoma and tumors with moderate differentiation. However, the differences were not significant (p values < 0.05). Significantly higher detection sensitivity was found for tumors of larger size than for tumors of smaller size (p value < 0.05). Our results suggest that Tc-TF chest SPECT is a helpful test for detecting Eso-Ca especially larger tumors.

Acute and chronic effects of isosorbide-5-mononitrate administration on effective renal plasma flow and the renin-aldosterone system in cirrhotic patients

BACKGROUND AND AIMS

Isosorbide-5-mononitrate (ISMO) has been shown to be effective in reducing the risk of variceal bleeding in patients with cirrhosis. However, recent studies have suggested that this drug compromises renal function. The present study was conducted to assess the acute and chronic effects of ISMO on effective renal plasma flow (ERPF) and the renin-aldosterone profile in cirrhotic patients.

METHODS

Fifteen cirrhotic patients were included in the present study. The mean arterial pressure (MAP), heart rate (HR), serum renin concentration (SR), ERPF and plasma aldosterone concentration (PA) were checked before ISMO treatment (baseline study), after a single oral dose of 20 mg ISMO (acute effect study) and after 3 weeks of ISMO treatment (chronic effect study).

RESULTS

Our data showed that the oral administration of a single dose (20 mg) of ISMO to cirrhotic patients was associated with significant decreases in ERPF (from 405.18 to 369.06 mL/min) and MAP (from 93.26 to 86.40 mmHg), and increases in HR (from 65.53 to 70.06 beats/min), SR (from 24.15 to 54.41 pg/mL), and PA (from 105.1 to 148.7 pg/mL). However, no significant changes were observed in HR, MAP, PA, SR, or ERPF after 3 weeks of ISMO treatment when compared with the baseline study.

CONCLUSIONS

The administration of ISMO causes a decrease in ERPF in cirrhotic patients and its use in patients with renal impairment should be considered cautiously.

Transient increase in alveolar epithelial permeability induced by volatile anesthesia with isoflurane

Fifteen patients undergoing surgery and receiving volatile anesthesia with isoflurane were enrolled as the study group. At the same time, 15 patients undergoing surgery with intravenous anesthesia drugs were included as a control group to compare each other. Before surgery, 1 h after surgery, and 1 week after surgery, we investigated these two groups of patients with technetium-99m-labeled diethylene triamine pentaacetic acid radioaerosol inhalation lung scan (DTPA lung scan), a test to evaluate lung ventilation (LV), which was evaluated by the first and equilibrium lung ventilation image and alveolar epithelial permeability (AP) which was evaluated by the half time (T1/2, minutes) of Tc-99m DTPA radioaerosol lung clearance. No significant change and abnormality of LV before surgery, 1 h after surgery, or 1 week after surgery was found in either group of patients. In addition, no significant change in AP before surgery (T1/2 = 64.0 +/- 17.3 min), 1 h after surgery (64.5 +/- 19.6 min), or 1 week after surgery (63.6 +/- 17.6 min) was found among the control group patients (p values > 0.05). However, a significant transient increase in AP was found in the study group 1 h after surgery (71.7 +/- 17.5 versus 51.2 +/- 16.4 min), but it recovered 1 week after surgery (51.2 +/- 16.4 versus 70.9 +/- 16.0 min) (p values < 0.05). We conclude that volatile anesthesia with isoflurane can induce transient increase of AP.

Radionuclide esophageal transit test to detect esophageal disorders in patients with mitral valve prolapse

AIM

The origin of chest discomfort in patients with mitral valve prolapse (MVP) is controversial. Our aim was to prospectively determine the incidence of esophageal disorders in MVP patients with or without chest pain.

METHODS

Twenty-five MVP patients with chest pain (group A) and 25 MVP patients without chest pain (group B) underwent evaluation of esophageal motility. None of the total of 50 MVP patients had significant coronary artery disease on cardiac catheterization. Esophageal motility including esophageal mean transit time (MTT), residual fraction (RF), and retrograde index (RI) was analyzed by the radionuclide esophageal transit test (RETT).

RESULTS

In comparison with 25 age and sex-matched healthy volunteers, the results showed that: (1) 19 patients in group A (76%) had abnormal RETT findings (48% of cases with prolonged MTT, 44% of cases with higher RF, and 60% of cases with higher RI); (2) 3 patients in group B (12%) had abnormal RETT findings (8% of cases with prolonged MTT, 4% of cases with higher RF, and 8% of cases with higher RI). In addition, mean values of MTT, RF, and RI in group A patients were significantly higher than in group B patients and healthy volunteers.

CONCLUSION

We found that the chest pain in some MVP patients may be related to abnormal esophageal motility, based on the evidence from a simple and noninvasive RETT.

Monitoring the effect of anticoagulants on left atrial thrombi in patients with rheumatic heart disease: assessment with 111In-oxine-labelled platelet heart scintigraphy and transoesophageal echocardiography

111In-oxine-labelled platelet heart scintigraphy (In-plt) was used to evaluate the activity of left atrial thrombi detected by transoesophageal echocardiography (TEE) in 16 cases of rheumatic heart disease. The effect of anticoagulants on the therapeutic intervention of these patients was evaluated by In-plt and TEE. In-plt was performed in all patients in serial pre- and post-anticoagulant therapy studies with anterior, 45 degrees left anterior oblique and left lateral views taken daily from the second to sixth day after injection of labelled platelets. After discontinuing anticoagulants for at least 1 week, only nine cases of left atrial thrombi were detected among the 16 cases by initial In-plt. After anticoagulants were again used for at least 3 weeks, all nine positive cases became negative on repeat In-plt. These results suggest that the diagnostic sensitivity of In-plt is lower than that of TEE. However, In-plt is more suitable and useful for evaluating the activity of left atrial thrombi after antithrombotic agent therapy and for monitoring the effect of anticoagulant therapy on left atrial thrombi in patients with rheumatic heart disease.

Tissue polypeptide specific antigen and squamous cell carcinoma antigen for early prediction of recurrence in lung squamous cell carcinoma

One of the major problems in the follow-up of patients with lung cancer is the early detection of recurrent disease. Tumor markers have been found helpful in detecting early recurrent disease. The aims of this study were to evaluate and compare the clinical usefulness of serial and simultaneous measurement of tissue polypeptide antigen (TPS) and squamous cell carcinoma (SCC) antigen for the early prediction of recurrence in patients with SCC of the lung. Sixty patients with SCC of the lung, including 25 patients with recurrence and 35 patients without recurrence after 1 year's follow-up after surgery, were enrolled in this study. The serial serum levels of TPS and SCC antigen were measured before surgery and 1 week, 1 month, 3 months, 6 months, 9 months, and 12 months after the operation for early detection of recurrence. The results revealed that (1) the mean serum values of TPS were significantly greater at all times after surgery in the 25 patients with recurrent SCC compared with the 35 patients without recurrent SCC, and (2) the mean serum values of SCC antigen were significantly greater only at 9 and 12 months after surgery in the 25 patients with recurrent SCC compared with the 35 patients without recurrent SCC. We conclude that TPS is a better marker than SCC antigen for early prediction of SCC recurrence in the lung.

Cytokeratin fragment 19 and squamous cell carcinoma antigen for early prediction of recurrence of squamous cell lung carcinoma

Sixty patients with squamous cell carcinoma (SCC) of the lung, including 25 cases with recurrence and 35 cases without recurrence 1 year after operation, were enrolled in this study. The serial serum levels of cytokeratin fragment 19 (CYFRA 21-1) and SCC antigen were measured before operation and 1 week, 1 month, 3 months, 6 months, 9 months, and 12 months after operation for early detection of recurrence. The results revealed that 1) mean serum values of CYFRA 21-1 were significantly higher at early and any times after operation in 25 patients with recurrent SCC when compared with 35 patients without recurrent SCC; and 2) mean serum values of SCC antigen were significantly higher until 9 and 12 months after operation, in 25 patients with recurrent SCC when compared with 35 patients without recurrent SCC. We conclude that CYFRA 21-1 is a better marker than SCC antigen for early prediction of SCC recurrence in the lung.

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.

Effects of single dose of 50mg captopril in patients with liver cirrhosis and ascites

BACKGROUND/AIMS

In patients with liver cirrhosis and ascites, the renin angiotensin system is usually activated. Such a correlation supports the hypothesis that activation of the renin-angiotensin system plays an influential role in the pathogenesis of ascites in liver cirrhosis.

METHODOLOGY

In this study, 25 patients with liver cirrhosis and ascites (10 females, 15 males; age: 45-67 years) were enrolled. We evaluated the acute effects of converting enzyme inhibitor (a single dose of 50 mg captopril taken orally) on glomerular filtration rate, effective renal plasma flow, filtration fraction, plasma renin activity, and plasma aldosterone.

RESULTS

Oral intake of a single 50 mg dose of captopril significantly decreased glomerular filtration rate (65 +/- 6 mL/min/1.73 m2 vs. 53 +/- 9 mL/min/1.73 m2), filtration fraction (21.2 +/- 2.7% vs. 15.5 +/- 4.1%), and plasma aldosterone (340 +/- 80 pg/mL vs. 247 +/- 42 pg/mL), but increased plasma renin activity (2.65 +/- 2.19 ng/mL/hr vs. 11.58 +/- 2.70 ng/mL/hr) and effective renal plasma flow (312 +/- 41 mL/min/1.73 vs. 356 +/- 60 mL/min/1.73 m2).

CONCLUSIONS

We suggest that oral intake of a single dose of 50 mg captopril can block the renin-angiotension system, and result in changes in renal hemodynamics and function in cirrhotic patients with ascites.

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.

The role of Tc-99m methoxyisobutylisonitrile scintimammography as compared to mammography in evaluating palpable breast masses of Taiwanese women

Eighty-one Taiwanese women (age range 31 to 79 years old) with palpable breast masses detected by mammography and or physical examination underwent technetium-99m methoxyisobutylisonitrile (Tc-99m-MIBI) scintimammography to assess its value in the detection of breast carcinomas and their differentiation from benign breast masses. The results showed that 58 of the 66 cases of breast carcinoma were detected by Tc-99m-MIBI scintimammography. Only 2 our of 15 patients with benign breast lesions had an abnormal scintimammographic finding. The mammography diagnosed 55 of the 66 cases of breast carcinoma, whilst 8 out of 15 patients with benign breast lesions had positive mammographic findings. The diagnostic sensitivity specificity and accuracy of Tc-99m-MIBI scintimammography were 88% 87% and 88%, respectively, whilst these parameters for mammography were 83%, 47% and 77%, respectively, regarding the differentiation of malignant from benign breast masses. We concluded that Tc-99m-MIBI scintimammography significantly improves the sensitivity and specificity for the detection of breast cancer in Taiwanese women with dense and small breasts.

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.

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.

Evidence of impaired gallbladder function in patients with liver cirrhosis by quantitative radionuclide cholescintigraphy

OBJECTIVE

The aim of this study was to understand gallbladder function in liver cirrhosis.

METHODS

Gallbladder function was measured in 45 patients with liver cirrhosis by Tc-99m-labeled imino-diacetic acid analog cholescintigraphy. Gallbladder function was represented by the filling fraction and the ejection fraction (EF). The patients were divided into three groups, based on cirrhotic severity, using the modified Child's classification: A = good, B = fair, and C = poor. Fifteen normal control subjects were selected for comparison.

RESULTS

There were no significant differences in filling fraction among all of the study groups. Normal controls had significantly higher 60-min EF values than did liver cirrhosis patients. Among the liver cirrhosis patients, class A patients had the highest EF values, and class C patients had the lowest EF values.

CONCLUSIONS

We found that liver cirrhosis may significantly impair the gallbladder emptying, based on the evidence of quantitative Tc-99m-labeled imino-diacetic acid analog cholescintigraphy findings.

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.

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.

Effects of butter and soybean oils on solid-phase gastric emptying in patients with functional dyspepsia

BACKGROUND

To determine whether vegetable fats cause a slower or quicker rate of gastric emptying (GE) than animal fats, we evaluated the effect of animal butter and vegetable soybean oil on solid-phase GE in patients with functional dyspepsia.

METHODS

Twenty-seven patients with functional dyspepsia were enrolled in this study. Radionuclide-labeled solid meals were used to evaluate GE. A study meal was composed of 206.8 kcal to 9.2 g protein, 45 g carbohydrate, and 10 g fat (formula 1, with animal butter: 26.2% saturated palmitic acid, 29.1% unsaturated oleic acid, 3.5% linoleic acid, and 0.5% linolenic acid; formula 2, with vegetable soybean oil: 11.0% saturated palmitic acid, 23.4% unsaturated oleic acid, 53.7% linoleic acid, and 7.8% linolenic acid). Each patient received formulas 1 and 2 as study meals on separate days. GE was represented by the gastric retention ratio of the study meal at 90 min (RR90): RR90 = residual radioactivity within the region of interest (ROI) covering the entire stomach at 90 min divided by the initial radioactivity within the ROI at 0 min.

RESULTS

The RR90 was 0.648 +/- 0.156 for formula 1 and 0.600 +/- 0.131 for formula 2. There was no significant difference for the RR99 between formulas 1 and 2 (paired Student's t test, p > 0.05). Of the 27 patients, 12 (44.4%) demonstrated an increased RR99 from formula 1 to formula 2, and the RR90 of remaining 15 (55.6%) patient decreased. In addition, neither the patients with increased RR90 nor those with decreased RR90 showed a difference of symptoms between the two study meals.

CONCLUSION

Our data suggest that there is no difference between these two types of fat on gastric emptying.

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.

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.

Gallium-67 citrate scan in extrapulmonary tuberculosis

AIM

Whole-body gallium scan was performed to evaluate the usefulness of gallium scan for detecting extrapulmonary tuberculosis (TB) lesions.

METHODS

Thirty-seven patients with extrapulmonary TB were included in this study. Four patients were found to have two lesions. Totally, 41 lesions were identified, including 19 TB arthritis, 8 spinal TB, 5 TB meningitis, 3 TB lymphadenopathy, 2 TB pericarditis, 1 TB peritonitis, 1 intestinal TB, 1 skin TB and 1 renal TB.

RESULTS

Of the 41 extrapulmonary TB lesions, gallium scan detected 32 lesions with a sensitivity of 78%. All the patients with TB meningitis showed negative gallium scan. When the five cases of TB meningitis were excluded, the detection sensitivity of gallium scan increased to 88.9% (32/36).

CONCLUSION

Our data revealed that gallium scan is a convenient and useful method for evaluating extrapulmonary TB lesions other than TB meningitis. We suggest that gallium scan be included in the clinical routine for patients with suspected extrapulmonary TB.

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

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.

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.

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.

Cytokeratin fragment 19 (CYFRA 21-1) and carcinoembryonic antigen for early prediction of recurrence of lung adenocarcinoma

Fifty patients with adenocarcinoma of the lung were enrolled in this study, including 20 patients with recurrence and 30 patients without recurrence 1 year after surgery. Serial serum levels of cytokeratin fragment 19 (CYFRA 21-1) and carcinoembryonic antigen (CEA) were measured before the operation and 1 week, 1 month, 3 months, 6 months, 9 months, and 12 months after surgery for the early detection of recurrence. The results revealed that the mean serum values of either CYFRA 21-1 or CEA were significantly higher until 9 and 12 months after surgery in the 20 patients with recurrent adenocarcinoma compared with the 30 patients without recurrent adenocarcinoma. We conclude that CYFRA 21-1 is not a better marker than CEA for early prediction of adenocarcinoma. We conclude that CYFRA 21-1 is not a better marker than CEA for early prediction of adenocarcinoma recurrence in lung.

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.