• Nuclear Medicine and Molecular Imaging
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• 제42권sup1호
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• pp.46-51
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• 2008

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal neoplasm of the gastrointestinal tract, and can be distinguished from the smooth muscle or neural tumors in approximately 95% of patients by expression of the KIT receptor tyrosine kinase (CD117). GISTs are known to have high malignant potential and none can be labeled definitely as benign. However, GISTs are unresponsive to standard sarcoma chemotherapy, and only complete surgical resection provides chance for cure. Although the imaging modality of choice is enhanced CT scan in patients with GIST, FDG PET can reflect the malignant potential of GIST. Clinical management of patients with GISTs has dramatically changed with the introduction of novel therapeutics, such as imatinib mesylate (Glivec). This has created a need to re-evaluate the existing criteria used to assess treatment response. FDG PET as functional imaging modality proved to be significantly more accurate than CT alone when assessing GIST response to imatinib. And, FDG PET and PET ICT have been found to be highly sensitive in detecting early response, and to be useful in predicting long-term response to imatinib in patients with recurrent or metastatic GISTs.

• Asian Pacific Journal of Cancer Prevention
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• 제17권7호
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• pp.3465-3468
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• 2016

Background: Fluorodeoxyglucose ($^{18}FDG$) PET/CT imaging has become an important component of the management paradigm in oncology. However, the significant imparted radiation exposure is a matter of growing concern especially in younger populations who have better odds of survival. The aim of this study was to estimate the effective dose received by patients having whole body $^{18}F$-FDG PET/CT scanning as per recent dose reducing guidelines at a tertiary care hospital. Materials and Methods: This prospective study covered 63 patients with different cancers who were referred for PET/CT study for various indications. Patients were prepared as per departmental protocol and 18FDG was injected at 3 MBq/Kg and a low dose, non-enhanced CT protocol (LD-NECT) was used. Diagnostic CT studies of specific regions were subsequently performed if required. Effective dose imparted by 18FDG (internal exposure) was calculated by using multiplying injected dose in MBq with coefficient $1.9{\times}10^{-2}mSv/MBq$ according to ICRP publication 106. Effective dose imparted by CT was calculated by multiplying DLP (mGy.cm) with ICRP conversion coefficient "k" 0.015 [mSv / (mG. cm)]. Results: Mean age of patients was $49{\pm}18$ years with a male to female ratio of 35:28 (56%:44%). Median dose of 18FDG given was 194 MBq (range: 139-293). Median CTDIvol was 3.25 (2.4-6.2) and median DLP was 334.95 (246.70 - 576.70). Estimated median effective dose imparted by $^{18}FDG$ was 3.69 mSv (range: 2.85-5.57). Similarly the estimated median effective dose by low dose (non-diagnostic) CT examination was 4.93 mSv (range: 2.14 -10.49). Median total effective dose by whole body 18FDG PET plus low dose non-diagnostic CT study was 8.85 mSv (range: 5.56-13.00). Conclusions: We conclude that the median effective dose from a whole body 18FDG PET/CT in our patients was significantly low. We suggest adhering to recently published dose reducing strategies, use of ToF scanner with CT dose reducing option to achieve the lower if not the lowest effective dose. This would certainly reduce the risk of second primary malignancy in younger patients with higher odds of cure from first primary cancer.

• 대한핵의학회지
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• 제35권6호
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• pp.398-400
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• 2001

The authors report a case of unsuspected myocardial ischemia detected during CoDe FDG PET (coincidence detection fluorodeoxyglucose positron emission tomogram) which was performed for the evaluation of a solitary pulmonary nodule. Camera-based FDG PET without attenuation correction often reveals false defect in the inferior wall of the left ventricle in normals due to excessive attenuation. However, this asymptomatic patient had increased uptake in the inferior wall suggesting ischemic myocardium. The scan finding was confirmed by Tl-201 myocardial SPECT and coronary angiogram. The patient then underwent successful PTCA of mild RCA and right ventricular branch followed by right upper lobectomy for small cell lung cancer.

• 핵의학기술
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• 제17권2호
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• pp.37-43
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• 2013

PET/CT검사는 목적장기 및 조직에 집적된 방사성의약품의 표준섭취계수(SUV, standardized uptake value)를 객관적 지표로 이용하여, 인체 내 각 장기의 생리화학반응에 대한 정성 및 정량분석이 가능하다. 본 연구는 PET/CT검사를 하는 환자에게 $^{18}F-FDG$ (fluororodeoxyglucose) 투여 후 안정 상태 유지 중 음악 청취 여부에 따른 SUV의 변화를 분석하고, 음악 청취가 안정을 취하는 환자의 주관적 만족도에 어떠한 영향을 미치는지 평가하였다. 2011년 4월부터 2013년 2월까지 서울성모병원과 부천성모 병원을 내원한 원발성 암 환자 중 $^{18}F-FDG$ PET/CT를 시행 하고, 추적검사를 통해 진료 받는 108명(평균연령 $55.61{\pm}12.41$세, 남자 48명, 여자 60명)을 대상으로 하였다. $^{18}F-FDG$ 투여 후, 1시간 안정 시 환자의 음악 청취 여부에 따라-최초 검사 시 음악 청취 없이 안정을 유지(A:최초 검사), 추적 검사 시 음악 청취를 하면서 안정을 유지(B: 추적 검사)-두 가지 그룹으로 분류하였다. 검사 종료 후 간 우엽의 중앙과 뇌의 3곳(전두엽, 후두엽, 측두엽)에 관심영역을 설정하여 SUV를 측정 후 SPSS software version 12.0K for window (SPSS Inc., Chicago, IL)를 이용해 paired t-test를 실시하여 통계적 유의성을 검증하였다(P>0.05). 또한 음악 청취 여부에 따른 고객만족도를 평가하기 위하여 1:1 설문지 조사법을 시행하였고 설문지는 Likert 5점 척도를 이용해 작성하여 단순빈도, 백분율, 평균값, 표준편차를 분석하였다. 음악 청취 여부에 따른 SUV의 변화는 관심영역 4곳 모두 유의하지 않은(전두엽 P=0.611, 후두엽 P=0.499, 측두엽 P=0.717, 간 P=0.334: P>0.05) 것으로 나타났으며, 고객만족도는 실험 A는 3.95점, 실험 B는 4.37점(5점 만점 기준)으로 실험 A에 비해 실험 B의 경우 0.42점 높게 나타나 실험 B에서 환자들이 더욱 만족하는 것으로 나타났다. $^{18}F-FDG$를 이용한 PET/CT 검사 시 방사성의약품 투여 후 음악청취는 SUV에 영향을 미치지 않고 심리적으로 편안 한 상태를 주어 환자의 만족도를 향상 시킬 수 있는 것으로 사료된다.

• Journal of Gynecologic Oncology
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• 제29권6호
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• pp.98.1-98.13
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• 2018

Objective: We describe a systematic review and meta-analysis of the performance of ${18}F$-fluorodeoxyglucose ($^{18}F-FDG$) positron emission tomography/computed tomography (PET/CT) for detecting metastasis in ovarian cancer. Methods: MEDLINE and Embase were searched for diagnostic accuracy studies that used $^{18}F-FDG$ PET or PET/CT for pre-treatment staging, using surgical findings as the reference standard. Sensitivities and specificities were pooled and plotted in a hierarchic summary receiver operating characteristic plot. Potential causes of heterogeneity were explored through sensitivity analyses. Results: Eight studies with 594 patients were included. The overall pooled sensitivity and specificity for metastasis were 0.72 (95% confidence interval [CI]=0.61-0.81) and 0.93 (95% CI=0.85-0.97), respectively. There was considerable heterogeneity in sensitivity ($I^2=97.57%$) and specificity ($I^2=96.74%$). In sensitivity analyses, studies that used laparotomy as the reference standard showed significantly higher sensitivity and specificity (0.77; 95% CI=0.67-0.87 and 0.96; 95% CI=0.92-0.99, respectively) than those including diagnostic laparoscopy (0.62; 95% CI=0.46-0.77 and 0.84; 95% CI=0.69-0.99, respectively). Higher specificity was shown in studies that confirmed surgical findings by pathologic evaluation (0.95; 95% CI=0.90-0.99) than in a study without pathologic confirmation (0.69; 95% CI=0.24-1.00). Studies with a lower prevalence of the FDG-avid subtype showed higher specificity (0.97; 95% CI=0.94-1.00) than those with a greater prevalence (0.89; 95% CI=0.80-0.97). Conclusion: Pre-treatment $^{18}F-FDG$ PET/CT shows moderate sensitivity and high specificity for detecting metastasis in ovarian cancer. With its low false-positive rate, it can help select surgical approaches or alternative treatment options.

• 대한두경부종양학회지
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• 제34권1호
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• pp.21-27
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• 2018

Background/Objectives: This study aimed to evaluate the changes of uptake around the sternoclavicular joint (SCJ) according to 18F-FDG PET images in patients with head and neck cancer who underwent neck dissection. Materials & Methods: Retrospectively, the medical records of patients who received selective or comprehensive neck dissection were reviewed. Preoperative and 1-year postoperative 18F-FDG PET images, if available, were analyzed by nuclear medicine physicians in both qualitative and quantitative manners. Correlation between the changes of uptake around SCJ and perioperative data were statistically analyzed. Results: Thirty-seven patients satisfying the inclusion criteria were enrolled. Seven patients with increased uptake around SCJ on 1-year postoperative 18F-FDG PET showed a correlation with radical or comprehensive neck dissection, accessory nerve sacrifice, and high postoperative SUVmax. When 20 patients with increased uptake around SCJ according to quantitative measurement were compared with other patients without increased uptake, no parameter was significantly different, except postoperative SUVmax. Bivariate logistic regression analysis revealed that the clinical symptom (shoulder or sternal pain) was significantly correlated with the extent of neck dissection (OR 0.227, CI 0.053-0.966, p=0.045) and spinal accessory nerve sacrifice (OR 13.500, CI 1.189-153.331, p=0.036). Conclusions: Increased uptake around SCJ on 1-year postoperative 18 F-FDG PET was correlated with either the radical or comprehensive procedure, as well as with accessory nerve sacrifice. This suggests that subjective analysis of 18F-FDG PET can be used to detect subclinical shoulder instability.

• 한국방사선학회논문지
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• 제17권5호
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• pp.701-707
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• 2023

PET/CT에서 ¹⁸F-FDG의 주사용량은 SUV(Standard Uptake Value)에 직접적인 영향을 끼쳐 판독결과에 영향을 미칠 수 있다. 따라서 정확한 ¹⁸F-FDG의 dose 값을 주사하는 것이 중요하다. 본 연구에서는 ¹⁸F-FDG 주사 시 플러싱 횟수에 따른 주사기와 혈관삽입기구의 잔류방사능간의 상관관계분석을 실시하였다. 실험장비는 CRC-25R 검량계, 3WAY line과 needle, 3 cc 주사기 및 50 cc 생리식염수를 사용하였고 결과값을 SP SS 21 Statics로 통계 분석하였다. 그 결과, 주사기와 혈관삽입기구의 총 잔류 방사능은 2회 플러싱 시 5.84 % 로 가장 높았고 5회 플러싱 시 1.49 % 로 가장 낮게 잔류하였다. 상관관계분석결과, 플러싱 횟수는 주사기의 잔류방사능과 -0.436, 혈관삽입기구와 - 0.300으로 음(-)의 상관관계를 보였다. 플러싱횟수에 따른 주사기, 혈관확보기구의 잔류 방사능 평균값을 일원배치 분산분석(One way - ANOVA)를 실시한 결과, 주사기의 잔류방사능은 4회부터 유의미한 감소를 보였고, 혈관확보기구의 잔류방사능은 5회부터 유의미한 감소를 보였다. 그러나 혈관확보기구의 평균 잔류방사능이 총 잔류방사능의 0.8 %라는 점을 고려할 때, 4회의 플러싱횟수가 가장 합리적으로 보인다.

• 한국융합학회논문지
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• 제9권1호
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• pp.433-440
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• 2018

FDG PET 영상에서 MTV는 종양의 전체 대사정도를 반영하여 종양의 체적을 나타낸다. 하지만 MTV는 영상재구성의 영향을 받게 된다. 본 연구의 목적은 팬텀실험을 통하여 영상재구성에 따라 SUVmax의 역치 값을 달리하여 실제 체적과 MTV의 상관관계를 평가해보고자 하였다. NEMA IEC Body 팬텀에 $^{18}F-FDG$를 구와 배후 방사능의 비율(4:1, 8:1, 10:1, 20:1)이 되도록 주입 후 영상을 획득하였다. 획득한 영상에 4가지 방법(OSEM3D, OSEM3D+PSF, OSEM3D+TOF, OSEM3D+TOF+PSF)으로 영상을 재구성한 후 다양한 SUVmax 역치 값을 적용하여 MTV의 변화를 비교해 보았다. 전반적으로 SUVmax 역치 값이 증가 할수록 MTV가 감소하였으며, 구와 배후방사능 비율이 증가할수록 동일한 SUVmax 역치 값에서 MTV가 감소하였다. PSF와 TOF+PSF재구성영상에서 40% 역치 값, OSEM3D와 TOF 재구성 영상에서는 45% 역치 값을 적용하였을 때 팬텀의 실제체적과 MTV의 높은 상관관계를 보였다. 이번 연구결과를 통하여 영상재구성에 따라 MTV 측정에 기초적인 자료로 제공되어 질 것으로 사료된다.

• Tuberculosis and Respiratory Diseases
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• 제55권3호
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• pp.280-286
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• 2003

목 적 : 폐암의 골전이 진단을 위해 흔히 이용하는 골주사는 예민도는 높으나 특이도가 낮아서, 악성 병변과 양성 병변을 구분하는 데에는 유용성이 낮다. 최근 전신 촬영이 가능한 $^{18}FDG$ PET이 암 진단에 널리 이용되고 있으므로 폐암의 골전이를 진단하는데 있어서 골주사와의 차이를 비교하기 위해 후향적 연구를 시행하였다. 방 법 : 폐암으로 진단된 환자 중 골수사와 전신 $^{18}FDG$ PET를 시행한 시간 차이가 1달 이내인 92명을 대상으로 하였다. 골전이의 판정은 골주사와 $^{18}FDG$ PET에서 이상 부위를 단순 X-선, 자기공명영상으로 평가하거나, 추적 영상검사로 확진하였다. 결 과 : 폐암의 골전이를 판정하는데 있어서 골주사의 민감도, 특이도, 정확도는 각각 59%, 71%, 68%이었으며, $^{18}FDG$ PET의 경우 각각 82%, 94%, 91%으로 $^{18}FDG$ PET이 골주사보다 특이도와 정확도에서 유의하게 우월하였다(p<0.0001). 결 론 : 폐암의 골전이를 평가하는데 있어서 $^{18}FDG$ PET은 전통적인 골주사보다 유용한 검사로 생각된다.

• Journal of Gastric Cancer
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• 제14권1호
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• pp.1-6
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• 2014

Aerobic glycolysis has been the most important hypothesis in cancer metabolism. It seems to be related to increased bioenergetic and biosynthetic needs in rapidly proliferating cancer cells. To this end, F-18 fluorodeoxyglucose (FDG), a glucose analog, became widely popular for the detection of malignancies combined with positron emission tomography/computed tomography (PET/CT). Although the potential roles of FDG PET/CT in primary tumor detection are not fully established, it seems to have a limited sensitivity in detecting early gastric cancer and mainly signet ring or non-solid types of advanced gastric cancer. In evaluating lymph node metastases, the location of lymph nodes and the degree of FDG uptake in primary tumors appear to be important factors affecting the diagnostic accuracy of PET/CT. In spite of the limited sensitivity, the high specificity of PET/CT for lymph node metastases may play an important role in changing the extent of lymphadenectomy or reducing futile laparotomies. For peritoneal metastases, PET/CT seems to have a poorer sensitivity but a better specificity than CT. The roles of PET/CT in the evaluation of other distant metastases are yet to be known. Studies including primary tumors with low FDG uptake or peritoneal recurrence seem suffer from poorer diagnostic performance for the detection of recurrent gastric cancer. There are only a few reports using FDG PET/CT to predict response to neoadjuvant or adjuvant chemotherapy. A complete metabolic response seems to be predictive of more favorable prognosis.