甲状腺18F-FDG弥漫性摄取增高的临床意义

G摄取增高者其抗甲状腺抗体阳性检出率增高,可能与桥本甲状腺炎有关.     

Diagnostic value of 18 F-FDG PET/CT in patients with fever of unknown origin

This study investigates the diagnostic value of (18) F-fluorodeoxyglucose positron emission tomography/computed tomography ((18) F-FDG PET/CT) in patients with 109 classical fever of unknown origin (FUO). Of the 48 (18) F-FDG PET/CT scans, 41 (85.4%) were interpreted as abnormal, and 25 (52.1% of all scans) were considered clinically helpful. The final cause of fever was determined in 41 patients (85.4%); infection (25%), malignancy (12.5%), non-infectious inflammatory disease (16.7%) and miscellaneous causes (31.3%). (18) F-FDG PET/CT contributed to the final diagnosis of FUO in 65.8%.     

Endometrioma presenting as a cavitary lung mass with intense 18F-FDG uptake on PET-CT

[18F]-fluoro-2-deoxy-D-glucose positron emission tomography computed tomography is a useful tool to suggest the diagnosis of malignant processes. However, false positive results are known to occur in benign lesions that have a high metabolic activity. Here we describe the unusual diagnosis of a pulmonary endometrioma in a 47-year-old woman, presenting as a cavitary lung mass with intense (18)F-FDG uptake on PET-CT.     

Pulmonary cavitations with increased 18F-FDG uptake revealing a thoracic endometriosis: A case report

Rationale:Thoracic endometriosis is a rare disorder that can involve airways, pleura and lung parenchyma. It is the most frequent form of extra-abdominopelvic endometriosis. Multiple lung cavitations are a rare feature of thoracic endometriosis.Patient concerns:A 46-year-old woman was referred to our hospital after incidental finding of multiple pulmonary cavitations with surrounding areas of ground glass opacity on a thoraco-abdominal computed tomography-scan performed for abdominal pain. Retrospectively, the patient also reported mild hemoptysis occurring 4 months ago.Diagnoses:Positron emission tomography–computed tomography scan revealed moderate and homogeneous [¹⁸F] fluoro-2-deoxy-D-glucose (¹⁸F-FDG) uptake in pulmonary cavitations (maximum standardized uptake value 5.7). The diagnosis of thoracic endometriosis was confirmed by histological examination of surgical resection of a left lower lobe cavitation.Interventions and outcome:Gonadotropin-releasing hormone analogues associated with add-back therapy was started. Four months after initiating pharmacological treatment, the chest computed tomography-scan showed a dramatic decrease in lung cavitations size.Lessons:Thoracic endometriosis is a rare disorder requiring a multidisciplinary management including gynaecologist, pulmonologist, radiologist, nuclear physician, pathologist and thoracic surgeon for early diagnosis and treatment. Our case report highlights that an increased ¹⁸F-FDG uptake can be found in thoracic endometriosis syndrome presenting as multiple lung cavitations.     

18F-FDG与99mTc同时心肌显像对不同缺损大小的模型研究

目的本研究通过模型试验旨在评价18F-FDG及99mTc同时心肌显像(DISA)的准确性.方法应用标准心脏模型进行心肌断层采集.模型内部备有不同大小的缺损块,模拟心肌梗死,分别为整个心肌容积的3%、5%、10%及15%.模型内部注入99mTc-O4-74 MBq(2mCi)及18F-FDG11.1MBq(300μCi).使用配备超高能准直器的Varicam双探头SPECT,行双核素心肌DISA.采用滤波反投影法,进行重建,产生双核素图像(99mTc,18F-FDG).采用5×5像素大小的感兴趣区,计算缺损区放射性计数,及与最大心肌计数的比值.结果所得图像中,缺损清晰可见.18F-FDG的图像中,缺损部位的放射性计数明显高于99mTc的图像,在小到中度缺损时尤其显著,而在大面积的缺损则差别减小.结论此项技术可能高估存活心肌的大小,在灌注显像显示小或中等的缺损时,代谢显像可能会产生部分假的不匹配.因此,应考虑到此影响的存在,定量分析可能会提高DISA评价心肌灌注-代谢估价的准确性.     

^18F-FDG在原发性胃淋巴瘤中的摄取特点及其与D-二聚体、LDH的关系

目的分析氟代脱氧葡萄糖（^18F-FDG）在原发性胃淋巴瘤（PGL）的摄取特点,探讨PET-CT显像对其诊断价值。方法回顾性分析53例经病理确诊为PGL患者（PGL组）的^18F-FDG PET-CT图像及临床资料,分析病灶最大标准摄取值（SUVmax）与D-二聚体、乳酸脱氢酶的关系。同期收集50例胃癌患者（胃癌组）、45例健康查体者（查体组）的PET-CT显像结果,对比分析PGL的PET-CT显像特点。结果胃癌组、查体组与PGL组SUVmax比较,差异均有统计学意义（P均〈0.05）;黏膜相关性PGL、胃癌与侵袭性PGL患者SUVmax比较差异有统计学意义（P均〈0.05）。在PGL患者中,不同病理分型、临床分期间SUVmax差异有统计学意义（P均〈0.05）;D-二聚体水平与SUVmax显示较好相关性（r=0.831,P〈0.01）。结论临床确诊或可疑PGL患者及时行PET-CT检查,结合D-二聚体水平,有利于其鉴别诊断、临床分期及治疗方案的确定。     

Persistent tumor 18F-FDG uptake after a few cycles of polychemotherapy is predictive of treatment failure in non-Hodgkin's lymphoma

BACKGROUND AND OBJECTIVE: Early recognition of the ineffectiveness of chemotherapy could result in lower cumulative drug toxicity and tumor burden at the start of salvage therapy, which might improve clinical outcome. Therefore, we studied the value of (18)F-FDG PET for early evaluation of response in patients with non-Hodgkin's lymphoma (NHL). DESIGN AND METHODS: We studied 28 patients by (18)F-FDG PET after a median of 3 cycles of polychemotherapy. The presence or absence of abnormal (18)F-FDG uptake was correlated to clinical outcome (median follow-up: 17.5 months, range 4-47 months). RESULTS: Five of 28 patients still had increased (18)F-FDG uptake in one or more sites previously shown to be involved by lymphoma at baseline evaluation. Only one of these five patients entered complete remission (CR), whereas among the 23 patients with negative (18)F-FDG PET studies, two died of toxicity during chemotherapy and all the others entered clinical CR (p<0.00001). All five patients with and 7/21 patients without residual abnormal (18)F-FDG uptake relapsed or reprogressed (positive predictive value for relapse: 100%, negative predictive value: 67%). By Kaplan-Meier analysis, progression-free survival (PFS) at 1 and 2 years was respectively 20+/-18% and 0% for (18)F-FDG PET positive patients and 81+/-9% and 62+/-12% for (18)F-FDG PET negative patients (p=0.0001). Overall survival (OS) at 1 and 2 years was respectively 20+/-18% and 0% for (18)F-FDG PET positive and 87+/-7% and 68+/-11% for (18)F-FDG PET negative patients (p<0.0001). INTERPRETATION AND CONCLUSIONS: Persistent tumoral (18)F-FDG uptake after a few cycles of polychemotherapy is predictive of CR, PFS and OS in NHL. Further studies are warranted to determine whether (18)F-FDG PET has a predictive value independent from conventional prognostic factors. However, the sensitivity of qualitative (18)F-FDG PET imaging in identifying patients with a poor outcome was insufficient. Earlier evaluation after only one cycle of chemotherapy and quantitative analysis might increase the sensitivity of 18F-FDG PET is predicting treatment failure.     

18F-FDG uptake in primary gastric malignant lymphoma correlates with glucose transporter 1 expression and histologic malignant potential

Positron emission tomography (PET) is used for staging and response evaluation in primary gastric lymphoma (PGL). However, the implications of [¹⁸F]-2-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) uptake in PGL at first diagnosis have not been reported. The relationship between ¹⁸F-FDG uptake and the expression of facilitative glucose transporters (GLUTs), hexokinase II (HK II), and Ki67, as well as malignant potential in PGL, was assessed in this study. We analyzed 23 patients with PGL [nine with diffuse large B-cell lymphoma (DLBCL); seven with high-grade mucosa-associated lymphoid tissue (MALT) lymphoma; and seven with low-grade MALT lymphoma]. The expression levels of GLUT1, GLUT3, HK II, and Ki67 were evaluated according to the percentage of positive area determined by immunohistochemistry. Standardized uptake values correlated significantly with pathological malignant potentials (low-grade/high-grade MALT lymphoma and DLBCL: p = 0.001–0.002), Ki67 (p < 0.001), and GLUT1 expression (p = 0.02). We determined that ¹⁸F-FDG uptake is related to GLUT1 expression and tumor histological grade as well as Ki67 in PGL.     

Early colon cancer detected by 18F-FDG PET

Positron emission tomography (PET) is a noninvasive functional imaging modality that can disclose the presence of a malignant disease. It has recently been reported that PET may be useful to detect primary colorectal cancer (CRC). We present the case of a 47-yr-old man with early colon cancer detected by ¹⁸F-fluorodeoxyglucose (FDG) PET. The patient consulted us because of a positive fecal occult blood test and focal FDG uptake in the pelvic cavity detected at a physical check-up. After the usual work up, he was diagnosed as having a sigmoid polyp, 16 mm in diameter. Subsequently, colonoscopic polypectomy was carried out. The surgical specimen was histologically diagnosed as a well-differentiated adenocarcinoma, invading the submucosal layer with lymphatic invasion. Therefore, the involved portion of the sigmoid colon was laparoscopically resected. The FDG PET carried out 1 yr after the operation, showed no abnormal FDG uptake. PET can noninvasively detect an early colon cancer as small as in our patient, as well as other cancers in the whole body. Therefore, we consider it suitable as a screening examination.     

Prognostic impact of 18F-FDG uptake on PET in non-small cell lung cancer patients with postoperative recurrence following platinum-based chemotherapy

BackgroundWhether fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) uptake within tumor cells differs between primary and recurrent lung cancers is unknown. The aim of this study was to investigate the prognostic significance of ¹⁸F-FDG uptake by comparing that measured preoperatively at the primary site to that measured postoperatively at sites of non-small cell lung cancer (NSCLC) recurrence. Only patients with postoperative recurrences who received platinum-based chemotherapy as the initial treatment after recurrence were included in the study.MethodsFifty-two patients underwent ¹⁸F-FDG positron emission tomography (PET) examinations before thoracotomy and at the time of recurrence after curative surgery. All recurrences were treated with platinum-based chemotherapy.Results¹⁸F-FDG uptake in the preoperative primary tumors was significantly higher than that in the recurrent tumors (p=0.028), demonstrating a statistically significant correlation (Pearson's correlation coefficient γ=0.482, p<0.001), especially in adenocarcinoma (AC) patients. Low ¹⁸F-FDG avidity within the primary tumor significantly correlated with the presence of epidermal growth receptor factor (EGFR) mutations. ¹⁸F-FDG uptake in the primary tumors was an independent prognostic factor for predicting outcome in NSCLC patients receiving platinum-based chemotherapy for the treatment of postoperative recurrence.ConclusionsIn NSCLC patients treated by chemotherapy for recurrence, preoperative measurements of ¹⁸F-FDG uptake may be a more powerful surrogate marker for predicting outcome when measured preoperatively at the primary tumor site rather than postoperatively at sites of recurrence.     

Quantitative comparison of ~(68)Ga-NGR and ~(18)F-FDG uptake in well-differentiated hepatocellular carcinoma bearing mice

正Objective To quantitatively compare the diagnostic capability of ~(68)Ga-NGR and ~(18)F-FDG in well-differentiated hepatocellular carcinoma(HCC)bearing mice by micro PET/CT imaging.Methods The in vitro cellular uptake,in vivo micro PET/CT imaging and biodistribution studies of ~(68)Ga-NGR and~(18)F-FDG were quantitatively compared in SMMC-7721-based well-differentiated HCC.The human fibrosarcoma(HT-1080)and human colorec-