Dosimetric Analysis of a Phase I Study of PSMA-Targeting Radiopharmaceutical Therapy With 177 LuLudotadipep in Patients With Metastatic Castration-Resistant Prostate Cancer

Objective@#177 Lutetium [Lu] Ludotadipep is a novel prostate-specific membrane antigen targeting therapeutic agent with an albumin motif added to increase uptake in the tumors. We assessed the biodistribution and dosimetry of [ 177 Lu]Ludotadipep in patients with metastatic castration-resistant prostate cancer (mCRPC). @*Materials and Methods@#Data from 25 patients (median age, 73 years; range, 60–90) with mCRPC from a phase I study with activity escalation design of single administration of [ 177 Lu]Ludotadipep (1.85, 2.78, 3.70, 4.63, and 5.55 GBq) were assessed. Activity in the salivary glands, lungs, liver, kidneys, and spleen was estimated from whole-body scan and abdominal SPECT/CT images acquired at 2, 24, 48, 72, and 168 h after administration of [ 177 Lu]Ludotadipep. Red marrow activity was calculated from blood samples obtained at 3, 10, 30, 60, and 180 min, and at 24, 48, and 72 h after administration. Organand tumor-based absorbed dose calculations were performed using IDAC-Dose 2.1. @*Results@#Absorbed dose coefficient (mean ± standard deviation) of normal organs was 1.17 ± 0.81 Gy/GBq for salivary glands, 0.05 ± 0.02 Gy/GBq for lungs, 0.14 ± 0.06 Gy/GBq for liver, 0.77 ± 0.28 Gy/GBq for kidneys, 0.12 ± 0.06 Gy/GBq for spleen, and 0.07 ± 0.02 Gy/GBq for red marrow. The absorbed dose coefficient of the tumors was 10.43 ± 7.77 Gy/GBq. @*Conclusion@#[ 177 Lu]Ludotadipep is expected to be safe at the dose of 3.7 GBq times 6 cycles planned for a phase II clinical trial with kidneys and bone marrow being the critical organs, and shows a high tumor absorbed dose.

One Versus Up‑to‑5 Lesion Measurements for Response Assessment by PERCIST in Patients with Lung Cancer / 대한핵의학회잡지

Purpose@#The optimal number of lesions to measure for response assessment from fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) is not validated for lung cancer. We compared 1 lesion and up-to-5 lesion measurements for response assessment in lung cancer per PET Response Criteria in Solid Tumors (PERCIST). @*Methods@#Patients with lung cancer with pre- and post-treatment PET/CT images were included. The standard uptake value corrected for lean body mass (SULpeak) of up-to-5 hottest target lesions was measured at each time point. The percent changes of ­SULpeak of the single hottest lesion and the sum of up-to-5 hottest lesions were computed. Pearson correlation coefficient evaluated the strength of association between the percent changes of ­SUL peak values from the 1 lesion and up-to-5 lesion analyses. Response categories were complete metabolic response (CMR) with no perceptible lesion; partial metabolic response (PMR), stable metabolic disease (SMD), or progressive metabolic disease (PMD) using the threshold of 30% and 0.8 unit change in ­SULpeak ; and unequivocal new lesion meant PMD. The concordance for response categorization was assessed by kappa statistics. @*Results@#A total of 40 patients (25 non-small cell lung cancer; 15 small cell lung cancer) were analyzed, all with 18F-FDGavid lung cancer. Average of 3 target lesions were measured for up-to-5 lesion analysis. Pearson’s r was 0.74 (P < 0.001) and increased to 0.96 (P < 0.001) when two outliers were excluded. Response categorization with 1 lesion and up-to-5 lesion analyses was concordant in 37 patients (92.5%, weighted kappa = 0.89). @*Conclusion@#Analyzing 1 lesion and up-to-5 lesions for response assessment by PERCIST showed high concordance in patients with lung cancer.

Predictive Value of Interim and End-of-Therapy 18F-FDG PET/CT in Patients with Follicular Lymphoma / 대한핵의학회잡지

PURPOSE: ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is the standard imaging modality for response evaluation in FDG-avid lymphoma, but the prognostic value is not established in follicular lymphoma (FL). This study investigated the prognostic value of Deauville 5-point scale (D5PS) from paired interim PET/CT (PET(Interim)) and end-of-induction therapy PET/CT (PET(EOI)) in patients with FL.METHODS: FL staging and response assessment PET/CT images from 2013 to 2015 were retrospectively reviewed. PET(Interim) was performed 3 or 4 cycles after chemotherapy and PET(EOI) after 6 or 8 cycles. D5PS scores of 1, 2, and 3 were considered as negative (−), and scores 4 and 5 were considered as positive (+). Statistical analysis was done using Cox regression analysis, Kaplan-Meier survival analysis, and the log-rank test.RESULTS: Thirty-three patients with set of baseline, interim, and end-of-induction therapy PET/CTstudies were included. Ten patients (30.3%) had progression. The median progression-free survival (PFS) was 38.8 months (range 3.5–72.7 months). On PET(Interim), 23 patients were negative and 10 were positive. On PET(EOI) scans, 29 patients were negative, and 4 were positive. On multivariate analysis, PET(EOI)(−) was associated with longer PFS. PET(Interim)(+) and PET(EOI)(+) patients had a significantly shorter PFS than PET(Interim)(−) patients (39.9 months, 95%confidence interval [CI] 23.0–56.9, versus 55.5months, 95%CI 49.7–61.2, p=0.005) and PET(EOI)(−) patients (14.2 months, 95% CI 8.5–19.8, versus 60.5 months, 95% CI 52.1–69.0, p<0.001).CONCLUSION: For patients with FL, PET(Interim) and PET(EOI) response is predictive of PFS, and PET(EOI)(+) is an independent prognostic factor for progression of FL.

Predictive Value of Interim and End-of-Therapy 18F-FDG PET/CT in Patients with Follicular Lymphoma / 대한핵의학회잡지

PURPOSE@#¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is the standard imaging modality for response evaluation in FDG-avid lymphoma, but the prognostic value is not established in follicular lymphoma (FL). This study investigated the prognostic value of Deauville 5-point scale (D5PS) from paired interim PET/CT (PET(Interim)) and end-of-induction therapy PET/CT (PET(EOI)) in patients with FL.@*METHODS@#FL staging and response assessment PET/CT images from 2013 to 2015 were retrospectively reviewed. PET(Interim) was performed 3 or 4 cycles after chemotherapy and PET(EOI) after 6 or 8 cycles. D5PS scores of 1, 2, and 3 were considered as negative (−), and scores 4 and 5 were considered as positive (+). Statistical analysis was done using Cox regression analysis, Kaplan-Meier survival analysis, and the log-rank test.@*RESULTS@#Thirty-three patients with set of baseline, interim, and end-of-induction therapy PET/CTstudies were included. Ten patients (30.3%) had progression. The median progression-free survival (PFS) was 38.8 months (range 3.5–72.7 months). On PET(Interim), 23 patients were negative and 10 were positive. On PET(EOI) scans, 29 patients were negative, and 4 were positive. On multivariate analysis, PET(EOI)(−) was associated with longer PFS. PET(Interim)(+) and PET(EOI)(+) patients had a significantly shorter PFS than PET(Interim)(−) patients (39.9 months, 95%confidence interval [CI] 23.0–56.9, versus 55.5months, 95%CI 49.7–61.2, p=0.005) and PET(EOI)(−) patients (14.2 months, 95% CI 8.5–19.8, versus 60.5 months, 95% CI 52.1–69.0, p<0.001).@*CONCLUSION@#For patients with FL, PET(Interim) and PET(EOI) response is predictive of PFS, and PET(EOI)(+) is an independent prognostic factor for progression of FL.

Effect of Pioglitazone in Combination with Moderate Dose Statin on Atherosclerotic Inflammation: Randomized Controlled Clinical Trial Using Serial FDG-PET/CT

BACKGROUND AND OBJECTIVES@#Non-statin therapy plus lower intensity statin might be an alternative in patients with coronary artery disease (CAD). A recent data suggested an anti-inflammatory therapy can reduce recurrent cardiovascular events and pioglitazone is also an intriguing inflammatory-modulating agent. However, limited data exist on whether pioglitazone on top of statins further attenuates plaque inflammation.@*METHODS@#Statin-naïve patients with stable CAD and carotid plaques of ≥3 mm were randomly prescribed moderate dose atorvastatin (20 mg/day), or moderate dose atorvastatin plus pioglitazone (30 mg/day) for 3 months. The primary endpoint was the change in the arterial inflammation of the carotid artery measured by 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) during 3 months.@*RESULTS@#Of the 41 randomized patients, 33 underwent an evaluation by fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT; 17 atorvastatin plus pioglitazone and 16 atorvastatin patients). The addition of pioglitazone significantly improved the insulin sensitivity and increased the high-density lipoprotein cholesterol after 3 months. Although a reduction in the (FDG) uptake by pioglitazone on top of atorvastatin in carotid arteries with plaque showed marginally statistical significance in the entire patient group (atorvastatin plus pioglitazone; −0.10±0.07 and atorvastatin −0.06±0.04, p=0.058), pioglitazone showed a further reduction of the fluorodeoxyglucose (FDG) uptake among patients who had a baseline FDG uptake above the median (atorvastatin plus pioglitazone; −0.14±0.04 and atorvastatin −0.03±0.03, p < 0.001).@*CONCLUSIONS@#Pioglitazone demonstrated marginally significant anti-inflammatory effects in addition to moderate dose atorvastatin. This may have been due to the lack of power of the study. However, pioglitazone may have an anti-inflammatory effect in those patients with high plaque inflammation (Trial registry at ClinicalTrials.gov, NCT01341730).

Effect of Pioglitazone in Combination with Moderate Dose Statin on Atherosclerotic Inflammation: Randomized Controlled Clinical Trial Using Serial FDG-PET/CT

BACKGROUND AND OBJECTIVES: Non-statin therapy plus lower intensity statin might be an alternative in patients with coronary artery disease (CAD). A recent data suggested an anti-inflammatory therapy can reduce recurrent cardiovascular events and pioglitazone is also an intriguing inflammatory-modulating agent. However, limited data exist on whether pioglitazone on top of statins further attenuates plaque inflammation. METHODS: Statin-naïve patients with stable CAD and carotid plaques of ≥3 mm were randomly prescribed moderate dose atorvastatin (20 mg/day), or moderate dose atorvastatin plus pioglitazone (30 mg/day) for 3 months. The primary endpoint was the change in the arterial inflammation of the carotid artery measured by 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) during 3 months. RESULTS: Of the 41 randomized patients, 33 underwent an evaluation by fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT; 17 atorvastatin plus pioglitazone and 16 atorvastatin patients). The addition of pioglitazone significantly improved the insulin sensitivity and increased the high-density lipoprotein cholesterol after 3 months. Although a reduction in the (FDG) uptake by pioglitazone on top of atorvastatin in carotid arteries with plaque showed marginally statistical significance in the entire patient group (atorvastatin plus pioglitazone; −0.10±0.07 and atorvastatin −0.06±0.04, p=0.058), pioglitazone showed a further reduction of the fluorodeoxyglucose (FDG) uptake among patients who had a baseline FDG uptake above the median (atorvastatin plus pioglitazone; −0.14±0.04 and atorvastatin −0.03±0.03, p < 0.001). CONCLUSIONS: Pioglitazone demonstrated marginally significant anti-inflammatory effects in addition to moderate dose atorvastatin. This may have been due to the lack of power of the study. However, pioglitazone may have an anti-inflammatory effect in those patients with high plaque inflammation (Trial registry at ClinicalTrials.gov, NCT01341730).

Prognostic Value of Pre- and Post-Treatment FDG PET/CT Parameters in Small Cell Lung Cancer Patients / 대한핵의학회잡지

PURPOSE: To evaluate the prognostic value of PET parameters obtained from pre- and post-treatment FDG PET/CT examinations in patients with SCLC.METHODS: Fifty-nine patients with initially diagnosed SCLC from 2009 to 2014 were included and had chemotherapy and/or concurrent chemoradiotherapy. FDG PET/CT examinations were performed before (PET1) and after (PET2) treatment to evaluate treatment response. A region of interest was placed over the primary lesion and metastatic lymph nodes within the thoracic cavity. PET parameters including change from PET1 to PET2 (Δ in %) were acquired: SUVmax, SUVpeak, MTV2.5, TLG, ΔSUVmax, ΔSUVpeak, ΔMTV and ΔTLG. Patient characteristics including staging, age, sex, LDH and response evaluation by RECIST were surveyed. Statistical analysis was done using Kaplan-Meier method and Cox regression analysis with respect to OS and PFS.RESULTS: The median follow-up was 9.6 months (2.5–80.5 months). 27 patients were LD and 32 were ED. Fortysix patients (78.0%) had died, and median OS was 8.6 months; 51 patients (86%) showed disease progression, and median PFS was 2.5 months. On univariate analysis, patients with ED, high interval change (ΔSUVmax and ΔSUVpeak) and low PET2 parameters showed longer OS and PFS. Multivariate analyses demonstrated that ΔSUVpeak (HR 2.6, P = 0.002) was an independent prognostic factors for OS, and MTV2.5 of PET2 (HR 2.8, P = 0.001), disease stage (HR 2.7, P = 0.003) and RECIST (HR 2.0, P = 0.023) were independent prognostic factors for PFS.CONCLUSIONS: Metabolic and volumetric PET parameters obtained from pre- and post-treatment FDG PET/CT examinations in patients with SCLC have significant prognostic information.

PERCIST in Perspective / 대한핵의학회잡지

Positron Emission tomography Response Criteria In Solid Tumors (PERCIST) version 1.0 was introduced in 2009 for objective assessment of tumor metabolic response using ¹⁸F-FDG PET/CT. Practical PERCIST: A Simplified Guide to PET Response Criteria in Solid Tumors 1.0 was published in 2016 to review and clarify some of the issues with the PERCIST. In this article, we reflect on the benefits and challenges of implementing PERCIST, and speculate on topics that could be discussed in PERCIST 1.1 in the future.

Prognostic Value of Pre- and Post-Treatment FDG PET/CT Parameters in Small Cell Lung Cancer Patients / 대한핵의학회잡지

PURPOSE@#To evaluate the prognostic value of PET parameters obtained from pre- and post-treatment FDG PET/CT examinations in patients with SCLC.@*METHODS@#Fifty-nine patients with initially diagnosed SCLC from 2009 to 2014 were included and had chemotherapy and/or concurrent chemoradiotherapy. FDG PET/CT examinations were performed before (PET1) and after (PET2) treatment to evaluate treatment response. A region of interest was placed over the primary lesion and metastatic lymph nodes within the thoracic cavity. PET parameters including change from PET1 to PET2 (Δ in %) were acquired: SUVmax, SUVpeak, MTV2.5, TLG, ΔSUVmax, ΔSUVpeak, ΔMTV and ΔTLG. Patient characteristics including staging, age, sex, LDH and response evaluation by RECIST were surveyed. Statistical analysis was done using Kaplan-Meier method and Cox regression analysis with respect to OS and PFS.@*RESULTS@#The median follow-up was 9.6 months (2.5–80.5 months). 27 patients were LD and 32 were ED. Fortysix patients (78.0%) had died, and median OS was 8.6 months; 51 patients (86%) showed disease progression, and median PFS was 2.5 months. On univariate analysis, patients with ED, high interval change (ΔSUVmax and ΔSUVpeak) and low PET2 parameters showed longer OS and PFS. Multivariate analyses demonstrated that ΔSUVpeak (HR 2.6, P = 0.002) was an independent prognostic factors for OS, and MTV2.5 of PET2 (HR 2.8, P = 0.001), disease stage (HR 2.7, P = 0.003) and RECIST (HR 2.0, P = 0.023) were independent prognostic factors for PFS.@*CONCLUSIONS@#Metabolic and volumetric PET parameters obtained from pre- and post-treatment FDG PET/CT examinations in patients with SCLC have significant prognostic information.

PERCIST in Perspective / 대한핵의학회잡지

Positron Emission tomography Response Criteria In Solid Tumors (PERCIST) version 1.0 was introduced in 2009 for objective assessment of tumor metabolic response using ¹⁸F-FDG PET/CT. Practical PERCIST: A Simplified Guide to PET Response Criteria in Solid Tumors 1.0 was published in 2016 to review and clarify some of the issues with the PERCIST. In this article, we reflect on the benefits and challenges of implementing PERCIST, and speculate on topics that could be discussed in PERCIST 1.1 in the future.

The Role of F-18 FDG PET/CT in Intrahepatic Cholangiocarcinoma / 대한핵의학회잡지

PURPOSE: The aim of this study was to evaluate the diagnostic and prognostic role of metabolic parameters of FDG PET/CT in patients with intrahepatic cholangiocarcinoma (ICC).METHODS: From December 2008 to December 2013, 76 FDG PET/CT scans performed for initial staging of ICC in a single institution (57 male and 19 female; mean age 68 ± 9 years) were retrospectively reviewed. Patients with history of other known malignancy were excluded. Detection rates of regional lymph node and distant metastasis by FDG PET/CT were analyzed in comparison with conventional imaging modalities such as CT or MRI. Metabolic parameters including maximum, peak and mean standardized uptake values (SUVmax, SUVpeak, SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG), glucose corrected SUV (SUVgluc), and glucose corrected TLG (TLGgluc) were measured for the primary tumor. Cut-off values for the metabolic parameters were calculated by ROC curve analysis, and used to dichotomize the patient groups. The overall survival time (OS) was calculated and compared using the Cox proportional hazard regression analysis.RESULTS: The median duration of follow-up period was 5.4 months (interquartile range: 1.45~15.45). FDG PET/CT showed higher sensitivity than conventional imagingmodalities in detection of regional node involvement (74.5 % vs. 61.8 %, p = 0.013). In six patients, distant metastasis was identified only by FDG PET/CT. The mean SUVmax, SUVpeak, SUVmean, MTV, and TLG for the primary tumor were 8.2 ± 3.1, 6.8 ± 2.5, 4.0 ± 0.8, 192.7 ± 360.5 cm3, and 823.7 ± 1615.4, respectively. Patients with higher (≥7.3, HR: 4.280, p = 0.001), higher SUVpeak (≥6.5, HR: 2.333, p = 0.020), higher SUVmean (≥3.9, HR: 2.799, p = 0.004), higher SUVgluc (≥8.1, HR: 2.648, p = 0.012), and higher TLGgluc (≥431.6, HR: 2.186, p = 0.030) showed significantly shorter survival time. By multivariate study, operability was an independent prognostic factor for longer survival (HR: 4.113, p= 0.005).CONCLUSION: FDG PET/CT is an important diagnostic imaging tool in the nodal staging and detection of distant metastasis in ICC patients. Metabolic parameters may have a significant role as prognostic factors in patients with ICC.

Analysis of treatment outcomes for primary tonsillar lymphoma

PURPOSE: Although each Waldeyer’s ring sub-site is considered an independent prognostic factor, few studies have assessed the prognosis and treatment of tonsillar lymphoma. Treatment outcomes were analyzed in patients with primary tonsillar lymphoma who were treated with chemotherapy and radiotherapy (RT). MATERIALS AND METHODS: Nineteen patients with diffuse large B-cell lymphoma were evaluated, with a median follow-up of 53 months. Age, sex, and histology, amongst other factors, were reviewed. Progression-free survival (PFS) and overall survival (OS) rates were analyzed. RESULTS: Most patients had Ann Arbor stage I-II (94.7%), IPI score of 0 (89.5%), and complete remission after chemotherapy (89.5%). The 5-year PFS and OS rates were 74.6% and 80%, respectively. In univariate analysis, the rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) regimen resulted in a better PFS than the cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) regimen (88.9% vs. 50.0%; p = 0.053). RT dose was related to the survival outcome (p = 0.010 for PFS, p = 0.044 for OS). Patients were classified into the CHOP + RT (>40 Gy) group and R-CHOP + RT (≤40 Gy) group. The 5-year PFS rates were 50% in the CHOP + RT group, and 100 % in the R-CHOP + RT group (p = 0.018). The 5-year OS rates were 66.7% and 100%, respectively (p = 0.087). CONCLUSION: Primary tonsillar lymphoma patients typically have favorable outcomes. Chemotherapy (R-CHOP) combined with relatively lower dose consolidative RT may be safe and effective for primary tonsillar lymphoma.

Clinical Significance of Observation without Repeated Radioiodine Therapy in Differentiated Thyroid Carcinoma Patients with Positive Surveillance Whole-Body Scans and Negative Thyroglobulin

BACKGROUND/AIMS: Currently, there is no consensus on the necessity of repeated radioiodine therapy (RAI) in patients who show iodine uptake in the thyroid bed on a diagnostic whole-body scan (DxWBS) despite undetectable thyroglobulin (Tg) levels after remnant ablation. The present study investigated the clinical outcomes of scan-positive, Tg-negative patients (WBS+Tg-) who did or did not receive additional RAI. METHODS: We retrospectively reviewed 389 differentiated thyroid carcinoma patients who underwent a total thyroidectomy and received high-dose RAI from January 2003 through December 2005. The patients were classified according to surveillance DxWBS findings and TSH-stimulated Tg levels 6 to 12 months after the initial RAI. RESULTS: Forty-four of the 389 patients (11.3%) showed thyroid bed uptake on a DxWBS despite negative Tg levels (WBS+Tg-). There was no difference in clinical and pathological parameters between WBS+Tg- and WBS-Tg- patients, except for an increased frequency of thyroiditis in the WBS+Tg- group. Among the 44 WBS+Tg- patients, 27 subjects were treated with additional RAI; 25 subjects showed no uptake in subsequent DxWBS. Two patients were evaluated only by ultrasonography (US) and displayed no persistent/recurrent disease. The other 17 patients received no further RAI; Eight patients and two patients showed no uptake and persistent uptake, respectively, on subsequent DxWBS. Six patients presented negative subsequent US findings, and one was lost to follow-up. Over the course of 53.2 +/- 10.1 months, recurrence/persistence was suspicious in two patients in the treatment group. CONCLUSIONS: There were no remarkable differences in clinical outcomes between observation and treatment groups of WBS+Tg- patients. Observation without repeated RAI may be an alternative management option for WBS+Tg- patients.

Histologic Base of Mild 18F-FDG Uptake in Simple Bone Cyst of Adult Rib: A Case Report with Multi-image Correlation / 핵의학분자영상

Simple bone cyst (SBC) is very rare in adult ribs. The diagnosis basically relies on conventional radiography and occasionally on CT. There has been no earlier publication on PET/CT diagnosis of SBC. We report a case of adult costal SBC diagnosed by positive 18F-fluorodeoxyglucose (FDG) uptake. Histology showed the FDG uptake to be associated with reactive woven bone formation and nonspecific chronic inflammation. Correlation of PET, CT, plain radiography and sonography are also described.

Role of 18F-fluorodeoxyglucose PET/CT in Recurrent Ovary Cancer / 핵의학분자영상

PURPOSE: To date, anatomical imaging modalities of the pelvis and tumor markers have been the mainstay of surveillance for recurrent ovary cancer. This study aimed to assess the role of 18F-FDG PET/CT in evaluation of ovary cancer recurrences, especially in comparison with enhanced CT and tumor marker CA 125. Materials and METHODS: 73 patients who had PET/CT scan for restaging of confirmed ovary cancer, and additional imaging with enhanced CT of the pelvis within one month were included. CA 125 level was available in all patients. From the PET/CT images, maximum standard uptake values (SUVmax) of suspected recurrence sites were recorded. Confirmation was available through re-operation or biopsy in 26 cases, and clinical assessment with series of follow-up images in 47. RESULTS: PET/CT had 93% sensitivity and 88% specificity for detecting recurrent ovary cancer. Enhanced CT of pelvis had sensitivity and specificity of 83% and 88%, and CA 125 50% and 95%. CONCLUSION: PET/CT has higher sensitivity for detecting recurrent ovary cancer compared to enhanced CT though the differences were not significant. PET/CT has significantly higher sensitivity than CA 125. However, the three tests all agreed in only 43% of the recurrence cases, and recurrence should be suspected when any of the tests, especially PET/CT, show positive findings.

Assessment of Cerebrovascular Reserve before and after STA-MCA Bypass Surgery by SPECT and SPM Analysis

OBJECTIVE: The purpose of this study was to objectively assess the efficacy of superficial temporal artery to middle cerebral artery (STA-MCA) bypass surgery using Technetium (Tc)-99m-ethyl cysteinate dimer (ECD) single photon emission computed tomography (SPECT) in patients who underwent STA-MCA bypass surgery. MATERIALS AND METHODS: Brain perfusion SPECT images obtained at baseline and after the administration of acetazolamide were reconstructed using statistical parametric mapping in 23 patients, both before and after STA-MCA bypass surgery. The clinical outcomes of the surgery were also recorded and compared with the hemodynamic changes. A voxel with an uncorrected p-value of less than 0.001 was considered to be statistically significant. RESULTS: SPECT images of the territory supplied by the bypass graft showed an increase in both cerebrovascular flow and reserve at baseline, and the increase was significantly higher following the administration of acetazolamide. All patients showed improvement of clinical symptoms and increased blood flow to the left temporal, parietal, and frontal cortices as well as the thalamus. CONCLUSION: Brain SPECT effectively and objectively demonstrated the improved outcomes of STA-MCA bypass surgery, and thus may be used in postoperative analyses.

PET-CT Manifestation of Candida Esophagitis / 핵의학분자영상

No abstract available.

Determination of Appropriate Sampling Frequency and Time of Multiple Blood Sampling Dual Exponential Method with 99mTc-DTPA for Calculating GFR / 핵의학분자영상

PURPOSE: To determine appropriate sampling frequency and time of multiple blood sampling dual exponential method with 99mTc-DTPA for calculating glomerular filtration rate (GFR). MATERIALS AND METHODS: Thirty four patients were included in this study. Three mCi of 99mTc-DTPA was intravenously injected and blood sampling at 9 different times, 5ml each, were done. Using the radioactivity of serum, measured by gamma counter, the GFR was calculated using dual exponential method and corrected with the body surface area. Using spontaneously chosen 2 data points of serum radioactivity, 15 collections of 2-sample GFR were calculated. And 10 collections of 3-sample GFR and 12 collections of 4-sample GFR were also calculated. Using the 9-sample GFR as a reference value, degree of agreement was analyzed with Kendall's tau correlation coefficients, mean difference and standard deviation. RESULTS: Although some of the 2-sample GFR showed high correlation coefficient, over or underestimation had evolved as the renal function change. The 10-120-240 min 3-sample GFR showed a high correlation coefficient (tau=0.93), minimal difference (Mean+/-SD=-1.784+/-3.972), and no over or underestimation as the renal function changed. The 4-sample GFR showed no better accuracy than the 3-sample GFR. CONCLUSIONS: In the wide spectrum of renal function, the 10-120-240 min 3-sample GFR could be the best choice for estimating the patients' renal function.

Incidental Visualization of Hepatic Hemangioma by Tc-99m-HDP Bone Scan / 대한핵의학회잡지

Hepatic hemangioma is the most common benign liver tumor and must be considered in the differential diagnosis of other space occupying hepatic masses. A 54-year-old man was referred to evaluate bone metastases of lung adenocarcinoma. In our case, we thought that a focal hepatic uptake in the bone scan was a metastatic lesion, because of underlying lung adenocarcinoma. However, the findings of abdominal CT and Tc-99m RBC scan results were deemed to be characteristic of hepatic hemangioma. The biopsy of the lesion was not performed.