Background: The pyrogen test represents an important parameter for the quality control (QC) of PE... more Background: The pyrogen test represents an important parameter for the quality control (QC) of PET tracers. However, the standard test proposed by the U.S. Pharmacopeia using limulus amebocyte lysates takes too long (about 1 h) for short-lived PET tracers. Endosafe® Portable Test System (PTS) has been approved by FDA and was claimed that it takes approximately 15 min to complete test procedure. The aim of this study was to evaluate PTS performance for PET tracers and head-to-head comparison with kinetic chromogenic analysis (KCA) that routinely used in NTUH PET center. Methods: With PTS and the conventional assay method, Lonza KCA assay systems, both experiments were performed on 3 consecutive batches of on-site produced F-18 FDG, C-11 PiB and N-13 NH3 by 6 different executors. All samples were tested with PTS method using 0.05~5.0EU/mL sensitivity cartridges. Additionally, for purpose to verify the accuracy of results from these two endotoxin test methods and the reliability regarding operative procedures among 6 QC staff, fabricated endotoxinpositive samples containing a fixed concentration of USP validated reference standard endotoxin (RSE) were also prepared and tested for blind testing. Results: The results of endotoxin detection among these two methods involving KCA and PTS were similar in most cases, although PTS exhibited significantly shorter time in testing (about 16~17 minutes required). However, results of blind test indicate that the control standard endotoxin used in KCA method has significant impact on the test results, such as inappropriate storage conditions of control standard endotoxin, and the KCA measurement is the most time-consuming method among these three methods. Conclusions: TPTS provided as reliable results as KCA method for endotoxin test and even more rapidly, therefore, is most suitable for short-lived PET radiotracers. Thus, the use of PTS will simplify the routine QC procedures of short-lived PET radiopharmaceuticals and prevent undetectable errors. Also, it will be of benefit to clinical application and future development of PET radiotracers.
We reported a 72-year-old male patient of malignant parotid squamous cell carcinoma (SCC) with ri... more We reported a 72-year-old male patient of malignant parotid squamous cell carcinoma (SCC) with right cervical lymph node metastases. The tumor and metastatic lymph nodes were not found after parotidectomy and radiotherapy (RT). For survey of recurrent cancer, 18Ffluorodeoxyglucose positron emission tomography (FDG PET) was performed twice and showed one hypermetabolic lesion in the right middle cervical region, which was not detected by computed tomography(CT), and the other two in the left posterior auricle and deep lower cervical regions. The final pathology confirmed recurrent metastatic SCC of the right cervical lymph nodes. In this case, the value of FDG-PET for earlier detection of recurrent lymph node metastases after RT was demonstrated.
Background/aims: The purpose of this study is to evaluate the efficacy of technetium-99m labeled ... more Background/aims: The purpose of this study is to evaluate the efficacy of technetium-99m labeled red blood cell liver single photon emission computed tomography (RBC liver SPET) in evaluating the diagnostic ability for differentiating the nature of a solitary liver tumor detected with ultrasonography in hepatitis B carrier patients. Methodology: One hundred and one hepatitis B carrier patients (56 males, 45 females, aged 13-70 years) with a solitary solid liver mass found on ultrasonography were included in this study. The final diagnosis was made after liver biopsy, aspiration with cytology and/or autopsy in 27 patients and after follow-up with both clinical and ultrasonography findings in 74 patients. Results: Hemangioma was found in 79 patients, hepatocellular carcinoma in 14, focal nodular hyperplasia in 5, fatty liver in 2, and metastasis in 1. The diagnostic sensitivity of RBC liver SPET for hemangioma, with a hyperechoic, hypoechoic, or isoechoic ultrasonography pattern, was between 75-80%, while the specificity for all patterns was 100%. For mixed-echoic lesions, the sensitivity was 100%, but the specificity was only 50%. Two false-positives were noted; both were mixed-echoic lesions. Conclusions: RBC liver SPET is useful for differentiating hemangioma from other liver tumors in hepatitis B carrier patients with a various sonographic patterns, especially for those who had a mixed-echoic sonographic liver mass.
To detect non-bacteriuric renal infection in a diabetic patient, though difficult but is very imp... more To detect non-bacteriuric renal infection in a diabetic patient, though difficult but is very important because early diagnosis and early treatment can prevent later complications such as renal abscess, renal hypertension or even end stage renal disease. Herein, we presented a case of diabetic patient with septicemia whose urine culture and renal ultrasonography were negative initially. By using a combination of dual isotope images and single photon emission computed tomography technique, an infectious lesion in the upper pole of left kidney was revealed, which was identified as acute focal bacterial nephritis by computed tomography four days later. This case report showed that 67Ga plus 99mTc dimercaptosuccinic acid images are useful in patients under clinical suspicion of renal infection, especially for those with negative urine analysis and/or urine culture initially.
A 54-year-old man of bladder and prostate cancers complained of painful left thigh swelling and f... more A 54-year-old man of bladder and prostate cancers complained of painful left thigh swelling and fever. Although the clinical presentation and imaging studies suggested infectious process, biopsy confirmed metastatic bladder cancer. F-18 FDG PET/CT scan demonstrated additional hypermetabolic focus at left psoas muscle. Skeletal muscle metastasis is rare and remains a diagnostic challenge, particularly in the absence of widespread metastasis. However, it should be included in the differential diagnosis for oncologic patients presenting with muscular pain refractory to antibiotics. It also highlighted the value of F-18 FDG PET/CT scan to detect occult metastatic foci and to monitor treatment response.
Background and purpose: Lymphoscintigraphy has been considered a useful tool for sentinel lymph n... more Background and purpose: Lymphoscintigraphy has been considered a useful tool for sentinel lymph node (SLN) mapping for malignant melanoma. This study evaluated the usefulness of SLN detection by lymphoscintigraphy and excision with intraoperative gamma probe in Taiwanese patients with malignant melanoma. Methods: Thirty six malignant melanoma patients in clinical stage I and II were enrolled. The Breslow thickness of the primary melanomas was </= 1.0 mm in 8 patients, 1.01 to 2.0 mm in 12 patients, 2.01 to 4.0 mm in 9 patients, >/= 4 mm in 3 patients, and unknown in 4 patients who were transferred from other hospitals and had no nodal or distant metastasis. SLN lymphoscintigraphy was performed with filtered 99mTc-sulfur colloid. An intraoperative gamma probe was used to identify the SLN for dissection. Results: A total of 44 SLNs were detected in 36 patients, with a mean of 1.22 SLNs per patient. The SLN detection rate by lymphoscintigraphy was 100%. During surgery, 39 of the 44 SLNs (88.6%) in 33 of 36 patients (91.7%) were identified. SLN metastasis was found in 8 of 39 dissected SLNs (20.5%) or in 8 of 36 patients (22.2%). The SLN metastatic rate in the patients with primary melanoma with Breslow thickness </= 2.0 mm was 10.0% (2/20), and in patients with Breslow thickness > 2.0 mm was 41.7% (5/12). Conclusions: Lymphoscintigraphy and intraoperative gamma probe are useful in localizing and dissecting SLN in patients with malignant melanoma. SLN mapping changed the clinical stage in 22.2% of melanoma patients.
Radionuclide imaging of the inferior vena cava (RIVC) was performed by injecting [99mTc] phytate ... more Radionuclide imaging of the inferior vena cava (RIVC) was performed by injecting [99mTc] phytate into a dorsal pedal vein, as an initial diagnostic procedure for eight patients with clinical features of Budd-Chiari syndrome. In five of them, membranous occlusion of the inferior vena cava (IVC) was proved by contrast venography and subsequent surgery. The other three patients, with histologically verified hepatocellular carcinoma, were proved to have tumor-induced narrowing or occlusion of the IVC by contrast venography. The RIVC findings include a sharply truncated inferior vena cava with marked hand-up of activity, extensive collaterals, and delayed visualization of the heart. Our results indicate that RIVC is as accurate and specific as contrast venography, by demonstrating the occlusion of the IVC and collateral circulation from the functional aspect. This simple and noninvasive method could therefore be used as a first-line test in patients with unexplained edema, ascites, superficial abdominal venous collaterals, and even in patients with hepatocellular carcinoma, for the detection of obstruction in the inferior vena cava.
A whole-body gallium-67 (Ga-67) scan of a 61-y-old male with diabetes mellitus who suffered from ... more A whole-body gallium-67 (Ga-67) scan of a 61-y-old male with diabetes mellitus who suffered from endogenous Klebsiella endophthalmitis is reported. The scan revealed right orbital and lower abdominal lesions. Urinary analysis revealed pyuria. The causes of endogenous Klebsiella endophthalmitis and the usefulness of Ga-67 are discussed.
Background: The pyrogen test represents an important parameter for the quality control (QC) of PE... more Background: The pyrogen test represents an important parameter for the quality control (QC) of PET tracers. However, the standard test proposed by the U.S. Pharmacopeia using limulus amebocyte lysates takes too long (about 1 h) for short-lived PET tracers. Endosafe® Portable Test System (PTS) has been approved by FDA and was claimed that it takes approximately 15 min to complete test procedure. The aim of this study was to evaluate PTS performance for PET tracers and head-to-head comparison with kinetic chromogenic analysis (KCA) that routinely used in NTUH PET center. Methods: With PTS and the conventional assay method, Lonza KCA assay systems, both experiments were performed on 3 consecutive batches of on-site produced F-18 FDG, C-11 PiB and N-13 NH3 by 6 different executors. All samples were tested with PTS method using 0.05~5.0EU/mL sensitivity cartridges. Additionally, for purpose to verify the accuracy of results from these two endotoxin test methods and the reliability regarding operative procedures among 6 QC staff, fabricated endotoxinpositive samples containing a fixed concentration of USP validated reference standard endotoxin (RSE) were also prepared and tested for blind testing. Results: The results of endotoxin detection among these two methods involving KCA and PTS were similar in most cases, although PTS exhibited significantly shorter time in testing (about 16~17 minutes required). However, results of blind test indicate that the control standard endotoxin used in KCA method has significant impact on the test results, such as inappropriate storage conditions of control standard endotoxin, and the KCA measurement is the most time-consuming method among these three methods. Conclusions: TPTS provided as reliable results as KCA method for endotoxin test and even more rapidly, therefore, is most suitable for short-lived PET radiotracers. Thus, the use of PTS will simplify the routine QC procedures of short-lived PET radiopharmaceuticals and prevent undetectable errors. Also, it will be of benefit to clinical application and future development of PET radiotracers.
We reported a 72-year-old male patient of malignant parotid squamous cell carcinoma (SCC) with ri... more We reported a 72-year-old male patient of malignant parotid squamous cell carcinoma (SCC) with right cervical lymph node metastases. The tumor and metastatic lymph nodes were not found after parotidectomy and radiotherapy (RT). For survey of recurrent cancer, 18Ffluorodeoxyglucose positron emission tomography (FDG PET) was performed twice and showed one hypermetabolic lesion in the right middle cervical region, which was not detected by computed tomography(CT), and the other two in the left posterior auricle and deep lower cervical regions. The final pathology confirmed recurrent metastatic SCC of the right cervical lymph nodes. In this case, the value of FDG-PET for earlier detection of recurrent lymph node metastases after RT was demonstrated.
Background/aims: The purpose of this study is to evaluate the efficacy of technetium-99m labeled ... more Background/aims: The purpose of this study is to evaluate the efficacy of technetium-99m labeled red blood cell liver single photon emission computed tomography (RBC liver SPET) in evaluating the diagnostic ability for differentiating the nature of a solitary liver tumor detected with ultrasonography in hepatitis B carrier patients. Methodology: One hundred and one hepatitis B carrier patients (56 males, 45 females, aged 13-70 years) with a solitary solid liver mass found on ultrasonography were included in this study. The final diagnosis was made after liver biopsy, aspiration with cytology and/or autopsy in 27 patients and after follow-up with both clinical and ultrasonography findings in 74 patients. Results: Hemangioma was found in 79 patients, hepatocellular carcinoma in 14, focal nodular hyperplasia in 5, fatty liver in 2, and metastasis in 1. The diagnostic sensitivity of RBC liver SPET for hemangioma, with a hyperechoic, hypoechoic, or isoechoic ultrasonography pattern, was between 75-80%, while the specificity for all patterns was 100%. For mixed-echoic lesions, the sensitivity was 100%, but the specificity was only 50%. Two false-positives were noted; both were mixed-echoic lesions. Conclusions: RBC liver SPET is useful for differentiating hemangioma from other liver tumors in hepatitis B carrier patients with a various sonographic patterns, especially for those who had a mixed-echoic sonographic liver mass.
To detect non-bacteriuric renal infection in a diabetic patient, though difficult but is very imp... more To detect non-bacteriuric renal infection in a diabetic patient, though difficult but is very important because early diagnosis and early treatment can prevent later complications such as renal abscess, renal hypertension or even end stage renal disease. Herein, we presented a case of diabetic patient with septicemia whose urine culture and renal ultrasonography were negative initially. By using a combination of dual isotope images and single photon emission computed tomography technique, an infectious lesion in the upper pole of left kidney was revealed, which was identified as acute focal bacterial nephritis by computed tomography four days later. This case report showed that 67Ga plus 99mTc dimercaptosuccinic acid images are useful in patients under clinical suspicion of renal infection, especially for those with negative urine analysis and/or urine culture initially.
A 54-year-old man of bladder and prostate cancers complained of painful left thigh swelling and f... more A 54-year-old man of bladder and prostate cancers complained of painful left thigh swelling and fever. Although the clinical presentation and imaging studies suggested infectious process, biopsy confirmed metastatic bladder cancer. F-18 FDG PET/CT scan demonstrated additional hypermetabolic focus at left psoas muscle. Skeletal muscle metastasis is rare and remains a diagnostic challenge, particularly in the absence of widespread metastasis. However, it should be included in the differential diagnosis for oncologic patients presenting with muscular pain refractory to antibiotics. It also highlighted the value of F-18 FDG PET/CT scan to detect occult metastatic foci and to monitor treatment response.
Background and purpose: Lymphoscintigraphy has been considered a useful tool for sentinel lymph n... more Background and purpose: Lymphoscintigraphy has been considered a useful tool for sentinel lymph node (SLN) mapping for malignant melanoma. This study evaluated the usefulness of SLN detection by lymphoscintigraphy and excision with intraoperative gamma probe in Taiwanese patients with malignant melanoma. Methods: Thirty six malignant melanoma patients in clinical stage I and II were enrolled. The Breslow thickness of the primary melanomas was </= 1.0 mm in 8 patients, 1.01 to 2.0 mm in 12 patients, 2.01 to 4.0 mm in 9 patients, >/= 4 mm in 3 patients, and unknown in 4 patients who were transferred from other hospitals and had no nodal or distant metastasis. SLN lymphoscintigraphy was performed with filtered 99mTc-sulfur colloid. An intraoperative gamma probe was used to identify the SLN for dissection. Results: A total of 44 SLNs were detected in 36 patients, with a mean of 1.22 SLNs per patient. The SLN detection rate by lymphoscintigraphy was 100%. During surgery, 39 of the 44 SLNs (88.6%) in 33 of 36 patients (91.7%) were identified. SLN metastasis was found in 8 of 39 dissected SLNs (20.5%) or in 8 of 36 patients (22.2%). The SLN metastatic rate in the patients with primary melanoma with Breslow thickness </= 2.0 mm was 10.0% (2/20), and in patients with Breslow thickness > 2.0 mm was 41.7% (5/12). Conclusions: Lymphoscintigraphy and intraoperative gamma probe are useful in localizing and dissecting SLN in patients with malignant melanoma. SLN mapping changed the clinical stage in 22.2% of melanoma patients.
Radionuclide imaging of the inferior vena cava (RIVC) was performed by injecting [99mTc] phytate ... more Radionuclide imaging of the inferior vena cava (RIVC) was performed by injecting [99mTc] phytate into a dorsal pedal vein, as an initial diagnostic procedure for eight patients with clinical features of Budd-Chiari syndrome. In five of them, membranous occlusion of the inferior vena cava (IVC) was proved by contrast venography and subsequent surgery. The other three patients, with histologically verified hepatocellular carcinoma, were proved to have tumor-induced narrowing or occlusion of the IVC by contrast venography. The RIVC findings include a sharply truncated inferior vena cava with marked hand-up of activity, extensive collaterals, and delayed visualization of the heart. Our results indicate that RIVC is as accurate and specific as contrast venography, by demonstrating the occlusion of the IVC and collateral circulation from the functional aspect. This simple and noninvasive method could therefore be used as a first-line test in patients with unexplained edema, ascites, superficial abdominal venous collaterals, and even in patients with hepatocellular carcinoma, for the detection of obstruction in the inferior vena cava.
A whole-body gallium-67 (Ga-67) scan of a 61-y-old male with diabetes mellitus who suffered from ... more A whole-body gallium-67 (Ga-67) scan of a 61-y-old male with diabetes mellitus who suffered from endogenous Klebsiella endophthalmitis is reported. The scan revealed right orbital and lower abdominal lesions. Urinary analysis revealed pyuria. The causes of endogenous Klebsiella endophthalmitis and the usefulness of Ga-67 are discussed.
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