PET/CT与低剂量CT诊断T1期肺癌

FDG-PET/CT对于T1期肺癌N期与M期病灶诊断优于普通CT,但受CT衰减校正(CT attenuation-correc-ted,CTAC)数据采集与重建模式影响与早期肺癌糖代谢低的特点,T1期(直径≤3 cm,实性、部分实性、非实性)原发灶检出与定性比较困难。肺部低剂量CT(low dose CT,LDCT)可以弥补前者缺点。通过改进数据采集重建模式,使CTAC图像质量达到LDCT质量要求或对高危患者追加肺部LDCT,制定合理随访计划,配合肿瘤标志物检查,发挥功能影像和解剖影像相结合,无创与微创方法相结合的优势,使其对T1期肺癌诊断的定位、定性、定量、定期与预后判断更准确。     

Dual-phase FDG PET/CT for predicting prognosis in operable breast cancer

PurposeWe aimed to investigate the role of dual-phase FDG PET/CT in predicting the prognosis of patients with operable breast cancer.MethodsWe retrospectively reviewed the data of 998 patients who underwent radical treatment for breast cancer. Before treatment, PET/CT scans were performed 1 and 2 h after FDG administration. The maximum standardized uptake value (SUVmax) at both time points (SUVmax1 and SUVmax2) in the primary tumor and the retention index (RI) were calculated. PET recurrence risk (PET-RR) was determined based on the SUVmax1 and RI, and disease-free survival (DFS) and overall survival (OS) were evaluated according to the metabolic parameters. Propensity score matching was performed to adjust for biological characteristics.ResultsThe cut-off values for SUVmax1 and RI were 3 and 5%, respectively. The 5-year DFS was 94.9% and 86.1% (P < 0.001), and the 5-year OS was 97.6% and 92.7% (P < 0.001) in the low and high PET-RR groups, respectively. In multivariate analysis, high T status, nodal metastasis, the triple-negative subtype, and high PET-RR were independent factors of poor DFS. Propensity score matching revealed similar findings (5-year DFS 91.8% vs. 88.6%, P = 0.041 and 5-year OS 97.1% vs. 94.2%, P = 0.240, respectively).ConclusionThe combined parameters of SUVmax1 and RI on dual-phase FDG PET/CT were useful for predicting prognosis of patients with breast cancer. Patients with a high SUVmax1 and a negative time course of FDG uptake had a favorable prognosis.     

Detection of incidental colorectal tumours with 18F‐labelled 2‐fluoro‐2‐deoxyglucose positron emission tomography/computed tomography scans: results of a prospective study

Aim This study assessed the clinical significance of incidental colorectal 2‐fluoro‐2‐deoxyglucose (FDG) uptake using ¹⁸F‐FDG positron emission tomography/computed tomography (PET/CT) scans and evaluated the importance of colonoscopy when incidental colorectal FDG uptake was observed. Method A prospective study was designed and conducted at a single institution over a 2‐year period. In patients undergoing PET/CT scans, all with FDG uptake in the colorectum were assigned to have colonoscopy and biopsy. The value of PET/CT scanning was studied by comparison with the colonoscopy and biopsy results. Results Among 10 978 PET/CT scans, one or more focal uptakes of FDG in the colorectum were observed in 148 (1.35%) patients. In 136 valid patients, malignant colorectal tumours and polyps were found in 23.5% and 20.5%, respectively,, while the colon in the other 56% was normal. A higher false‐positive rate was found in the right colon compared with the distal colorectum (66.2%vs 36.7%, P = 0.004). A significant increase of the maximum standardized uptake (SUVmax) value was found among normal, polyps and cancer groups. Multivariate analysis revealed that SUVmax was the risk factor for predicting colorectal cancer or polyps and FDG uptake in the right colon was a negative predictive factor for finding cancers or polyps. Conclusions Our study proves the necessity of colonoscopy when incidental FDG uptake is found on PET/CT imaging. The false‐positive FDG uptake is more commonly observed in the right colon. Although the SUVmax value is higher in cancer patients, a high SUVmax value does not necessarily result in malignancies.     

FDG PET/CT during neoadjuvant chemotherapy may predict response in ER-positive/HER2-negative and triple negative,but not in HER2-positive breast cancer

BackgroundResponse monitoring with MRI during neoadjuvant chemotherapy (NAC) in breast cancer is promising, but knowledge of breast cancer subtype is essential. The aim of the present study was to evaluate the relevance of breast cancer subtypes for monitoring of therapy response during NAC with 18F-FDG PET/CT.MethodsEvaluation included 98 women with stages II and III breast cancer. PET/CTs were performed before and after six or eight weeks of NAC. FDG uptake was quantified using maximum standardized uptake values (SUVmax). Tumors were divided into three subtypes: HER2-positive, ER-positive/HER2-negative, and triple negative. Tumor response at surgery was assessed dichotomously (presence or absence of residual disease) and ordinally (breast response index, representing relative change in tumor stage). Multivariate regression and receiver operating characteristic (ROC) analyses were employed to determine associations with pathological response.ResultsA (near) complete pathological response was seen in 19 (76%) of 25 HER2-positive, 7 (16%) of 45 ER-positive/HER2-negative, and 20 (71%) of 28 triple negative tumors. Multivariate regression of pathological response indicated a significant interaction between change in FDG uptake and breast cancer subtype. The area under the ROC curve was 0.35 (0.12–0.64) for HER2-positive, 0.90 (0.76–1.00) for ER-positive/HER2-negative, and 0.96 (0.86–1.00) for triple negative tumors. We found no association between age, stage, histology, or baseline SUVmax and pathological response.ConclusionResponse monitoring with PET/CT during NAC in breast cancer seems feasible, but is dependent on the breast cancer subtype. PET/CT may predict response in ER-positive/HER2-negative and triple negative tumors, but seems less accurate in HER2-positive tumors.     

慢性肿块型胰腺炎的18F-FDG PET/CT影像学表现

目的探讨慢性肿块型胰腺炎18F-FDG PET/CT影像学表现。方法回顾性分析6例经手术病理证实的慢性肿块型胰腺炎的18F-FDG PET/CT影像资料和临床资料。结果 6例共检出6个病灶,3个位于胰头,3个位于胰尾;平均大小3.0cm×2.7cm。CT平扫6个病灶呈均匀等密度,未见钙化灶,平均CT值约为36HU;增强扫描全部病灶呈延迟期强化。全部病灶18F-FDG摄取呈局灶性增高,最大标准摄取值（SUVmax）1.6～5.3,平均SUVmax3.92±1.49,高于正常胰腺组织的2.05±0.39（t=-3.648,P=0.015）。3例病灶累及胰头,胆总管及胰管不同程度扩张,呈双管征,胰体尾部轻度萎缩;3例病灶累及胰尾,胆总管及胰管未见扩张,胰体尾部未见萎缩。病灶邻近的主要血管均未受侵。全部病例胰周及腹膜后淋巴结未见18F-FDG局灶性摄取增高,未见远处脏器或（和）组织转移。结论 18 F-FDG PET/CT对诊断慢性肿块型胰腺炎具有一定价值。     

18F-脱氧葡萄糖正电子发射计算机断层显像CT检查在前列腺癌诊断和分期中的应用价值

目的 评价18F-脱氧葡萄糖(18F-FDG)正电子发射计算机断层显像CT检查(PET/CT)在前列腺癌诊断和分期中的应用价值.方法 经手术或穿刺活检病理证实为前列腺癌患者40例,年龄52 ～ 78岁,平均67岁.其中T24例,T316例,T420例.行18F-FDG PET/CT及99Tcm-MDPECT骨显像检查,统计PET/CT显像对前列腺癌原发灶、淋巴结转移及骨转移诊断的敏感性,对比分析PET/CT显像及99Tcm-MDPECT骨显像对骨转移的诊断效果.结果 40例患者中,18F-FDG PET/CT检查显示前列腺局部结节状放射性浓聚17例,对原发灶诊断敏感性为43％.17例淋巴结转移患者中CT检查发现8例,18F-FDG PET/CT检查发现15例,诊断敏感性为88％,其中5例患者因PET/CT检查改变了临床分期以及治疗方案.18F-FDG PET/CT对骨转移诊断的敏感性与99Tcm-MDP骨显像相近,但特异性(95％)和准确率(96％)均明显高于99Tcm-MDP骨显像,其中6例患者因PET/CT检查改变了临床分期,2例改变了治疗方案.结论 18F-FDG PET/CT对前列腺癌淋巴结转移和骨转移有较高诊断价值,对前列腺的分期具有特殊优势,可为临床医生制定治疗方案提供可靠依据.     

The value of 18F‐FDG PET/CT in diagnosing and localising deep sternal wound infection to guide surgical debridement

Deep sternal wound infection (DSWI) is a severe complication in patients after open heart surgery (OHS). But there is a lack of appropriate imaging tool to detect the infection sites, which may lead to incomplete debridement. The present study aims to investigate the value of ¹⁸F‐fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F‐FDG PET/CT) in comparison with CT scan in diagnosing and localising DSWI. A total of 102 patients with DSWI after OHS were retrospectively collected from January 2012 to December 2017 in our hospital. All the patients had surgical debridements for DSWI with pretreatment imaging of either ¹⁸F‐FDG PET/CT or CT scan. The sensitivity, specificity, and accuracy of localising infection sites were compared between PET/CT and CT groups, with surgical, microbiological, and histopathological findings as the gold standard. The length of hospital stays and the rate of recurrence were also compared. Ten patients in the PET/CT group had a follow‐up PET/CT scan after debridement, and the correlations between the changes of PET/CT findings and surgical outcomes were analysed. ¹⁸F‐FDG PET/CT is more accurate than CT in diagnosing and localising DSWI after OHS, which leads to a more successful surgical debridement with a lower rate of recurrence and a shorter length of hospital stay. In addition, follow‐up PET/CT after debridement could evaluate the treatment effect.     

Preoperative lymph-node staging of invasive urothelial bladder cancer with 18F-fluorodeoxyglucose positron emission tomography/computed axial tomography and magnetic resonance imaging: correlation with histopathology

OBJECTIVE: The treatment and prognosis of bladder cancer are based on the depth of primary tumour invasion and the presence of metastases. A highly accurate preoperative tumour, node, metastasis (TNM) staging is critical to proper patient management and treatment. This study retrospectively investigated the value of 1?F-fluorodeoxyglucose (FDG) positron emission tomography/computed axial tomography (1?F-FDG PET/CT) and magnetic resonance imaging (MRI) for preoperative N staging of bladder cancer. Material and methods. From June 2006 to January 2008, 48 consecutive patients diagnosed with bladder cancer were referred to preoperative staging including MRI and 1?F-FDG PET/CT. Eighteen out of 48 patients underwent radical cystoprostatectomy including removal of lymph nodes for histology, and were included in the study. Values of 1?F-FDG PET/CT and MRI for regional N staging were compared to histopathology findings, the gold standard. Results. 1?F-FDG PET/CT and MRI were performed in 18 patients. The specificities for detection of lymph-node metastases for MRI and 1?F-FDG PET/CT were 80% (n = 15) and 93.33% (n = 15), respectively. The negative predictive values were 80% (n = 15) and 87.5% (n = 16) for MRI and 1?F-FDG PET/CT, respectively. The differences in specificity and negative predictive values were not statistically significant. Conclusions. No significant statistical difference between 1?F-FDG PET/CT and MRI for preoperative N staging of urothelial bladder cancer was found in the study. However, the trend of the data indicates an advantage of 1?F-FDG PET/CT over MRI. Larger prospective studies are needed to elucidate the role of 1?F-FDG PET/CT in N staging of bladder cancer.     

Correlation between Quantified Breast Densities from Digital Mammography and 18F-FDG PET Uptake

Abstract:  To correlate breast density quantified from digital mammograms with mean and maximum standardized uptake values (SUVs) from positron emission tomography (PET). This was a prospective study that included 56 women with a history of suspicion of breast cancer (mean age 49.2 ± 9.3 years), who underwent 18F-fluoro-2-deoxyglucose (FDG)-PET imaging of their breasts as well as digital mammography. A computer thresholding algorithm was applied to the contralateral nonmalignant breasts to quantitatively estimate the breast density on digital mammograms. The breasts were also classified into one of four Breast Imaging Reporting and Data System categories for density. Comparisons between SUV and breast density were made using linear regression and the Student's t -test. Linear regression of mean SUV versus average breast density showed a positive relationship with a Pearson's correlation coefficient of R² = 0.83. The quantified breast densities and mean SUVs were significantly greater for mammographically dense than nondense breasts (p < 0.0001 for both). The average quantified densities and mean SUVs of the breasts were significantly greater for premenopausal than postmenopausal patients (p < 0.05). 8/51 (16%) of the patients had maximum SUVs that equaled 1.6 or greater. There is a positive linear correlation between quantified breast density on digital mammography and FDG uptake on PET. Menopausal status affects the metabolic activity of normal breast tissue, resulting in higher SUVs in pre- versus postmenopausal patients.     

18F-fluorocholine PET/CT compared with extended pelvic lymph node dissection in high-risk prostate cancer

Purpose

To compare ¹⁸F-fluorocholine positron-emission tomography/computed tomography (PET/CT) with extended pelvic lymph node dissection (ePLND) for the detection of lymph node metastases in a large cohort of patients with high-risk prostate cancer.

Materials and methods

Patients with prostate-specific antigen levels between 20 and 99 ng/mL and/or Gleason score 8–10 cancers, planned for treatment with curative intent following a negative or inconclusive standard bone scan, were investigated with ¹⁸F-fluorocholine PET/CT followed by an ePLND. None of the patients received hormonal therapy prior to these staging procedures. Results for PET/CT were compared on a per-patient basis with histopathology from ePLND. Sensitivity, specificity, positive and negative predictive values were calculated.

Results

PET/CT detected a total of 76 suspected lymph node metastases and four suspected bone metastases in 33 (29 %) of the 112 included patients. Of these, 35 suspected lymph node metastases, only within the anatomical template area of an ePLND, were found in 21 of the patients. Histopathology of the ePLND specimens detected 117 lymph node metastases in 48 (43 %) of the 112 patients. Per-patient sensitivity, specificity, positive and negative predictive values for ¹⁸F-fluorocholine PET/CT for lymph node metastases within the ePLND template were 0.33, 0.92, 0.76 and 0.65, respectively. Only 11 patients had lymph nodes larger than 10 mm that would have been reported by CT alone.

Conclusions

¹⁸F-fluorocholine PET/CT detects lymph node metastases in a significant proportion of patients with high-risk prostate cancer with a high specificity, but low sensitivity.     

Clinical Significance of Incidental Colonic 18F-FDG Uptake on PET/CT Images in Patients with Gastric Adenocarcinoma

Background and Objectives

We assessed the ability of positron emission tomography?Ccomputed tomography (PET/CT) to detect synchronous colonic pathology and determined the significance of 18F-fluorodeoxyglucose (¹⁸F-FDG) activity in the colon of gastric cancer patients.

Methods

A total of 239 gastric cancer patients who underwent PET/CT and colonoscopy preoperatively were included. FDG uptake patterns on PET/CT were classified as (1) group A, focal; (2) group B, diffuse; and (3) group C, no uptake. The PET/CT findings were compared with the results of concurrent colonoscopy.

Results

In group A, a total of 123 polyps of >0?mm were observed. Of these, nine polyps were colonic adenocarcinomas and six were high-grade dysplasia. The incidence of colonic adenocarcinomas was significantly higher in group A than in the other two groups (p?=?0.037). There was a significant correlation between SUVmax values and incidence of colonic polyps of >10?mm (r?=?0.471, p?=?0.04). The distribution pattern of SUVmax in polyps with adenoma (>10?mm) was less homogenous than in polyps (>10?mm) with adenocarcinoma.

Conclusions

The focal colonic FDG uptake in PET/CT requires colonoscopic confirmation. The suspicion of colonic malignancy increased in the presence of polyps >10?mm that showed a positive correlation with the SUVmax.     

11C-胆碱PET/CT显像在前列腺癌诊断中的应用价值

目的探讨11C-胆碱PET/CT显像在前列腺癌诊断中的临床价值。方法42例PSA升高的可疑前列腺癌患者为研究组,5例浸润性膀胱癌患者为阴性对照组,静脉注射7.4 MBq/kg 11C-胆碱5 min后行仰卧位盆腔PET/CT显像,可疑转移者行全身显像。测量最高标准化摄取值(SUVmax)并计算前列腺病灶与肌肉组织SUVmax的比值T/B。结果经病理证实为前列腺癌者22例,良性前列腺增生(BPH)者25例(含对照组),两者的T/B值分别为4.32±1.35和1.68±1.23.差异有统计学意义(P<0.01)。11C-胆碱PET/CT显像诊断前列腺癌的敏感性为81.8%(18/22),特异性为84.0%(21/25)。PET/CT显示9例前列腺癌患者伴骨和(或)淋巴结及肺转移。22例前列腺癌者SUVmax与PSA值、Gleason评分值无相关性(P>0.05)。结论11C-胆碱PET/CT显像对前列腺癌的诊断有重要价值。     

Diagnostic Performance of CT Attenuation Values of Focal 18F‐FDG Avid Breast Lesions Detected on Whole‐Body PET‐CT in Postoperative Breast Cancer Patients

To assess whether CT attenuation values help in differentiating benign from malignant etiology of focal ¹⁸F‐FDG avid breast lesions detected on whole‐body PET/CT exam in postoperative breast cancer patients. Institutional review board approval and waived informed consent were obtained for this HIPAA‐compliant retrospective study. Between January 2009 and July 2011, a total of 85 patients had 97 focal ¹⁸F‐FDG avid breast lesions on whole‐body PET/CT. Of these, 54 (56%) lesions were biopsy‐proven primary invasive breast carcinoma that had not undergone treatment at the time of PET/CT, 35 (36%) were benign lesions, and 8 were locally recurrent breast carcinoma. Mean attenuation values were retrospectively measured in Hounsfield units (HU) for the correlative lesion on the CT portion of the exam. Receiver‐operating characteristic curves (ROC) were calculated to determine the optimal cutoff values of HU that would best discriminate between benign and malignant lesions. Interobserver agreement for measured mean attenuation values was assessed by calculating the intraclass correlation coefficient (ICC). Mean HU for the benign lesions group and the local recurrence lesions group was ?11.0 ± 30.3 versus 32.9 ± 6.87 (p < 0.0002). ROC curve analysis comparing benign breast lesions to local recurrence lesions found an optimal cutoff value of 17 HU (area under curve = 0.982, p < 0.0001, Sensitivity = 100%, Specificity = 89%). ICC with regard to interobserver agreement in measuring the mean HU of the benign lesions was 0.84 (95% confidence interval 0.64–0.93) and for the malignant lesions was 0.88 (95% confidence interval 0.77–0.94). A CT attenuation threshold value of less than 17 HU suggests benign etiology of focal ¹⁸FDG avid breast lesions in postoperative breast cancer patients. If confirmed by additional studies, these findings may provide additional information to guide the treating physician regarding decisions for supplementary imaging or the need to biopsy.     

Significance of 18F‐fluorodeoxyglucose positron‐emission tomography/computed tomography for the postoperative surveillance of advanced renal cell carcinoma

OBJECTIVES

To evaluate the role of ¹⁸F‐fluorodeoxyglucose (FDG) positron‐emission tomography (PET)/computed tomography (CT) for the surveillance of patients with renal cell carcinoma (RCC) who have a high risk of local recurrence or distant metastasis, by comparing the results with those of conventional imaging methods.

PATIENTS AND METHODS

Sixty‐three patients with RCC had conventional imaging studies and FDG PET/CT during the follow‐up after surgical treatment. Their pathological stages were T2 in 28 patients, T3a in 14, T3b in 19 and T4 in two; lymph‐node or distant metastases were present in 12 patients. Suspicious recurrent or metastatic lesions were confirmed by histopathology or by clinical follow‐up. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of conventional surveillance methods and FDG PET/CT were analysed. The difference in the accuracy of FDG PET/CT by nuclear grade and histological subtype of tumours was also assessed.

RESULTS

The FDG PET/CT accurately classified the presence of a recurrence or metastasis in 56 (89%) patients. FDG PET/CT had an 89.5% sensitivity, 83.3% specificity, 77.3% positive predictive value, 92.6% negative predictive value, and 85.7% accuracy in detecting recurrence or metastasis, which was not significantly different from the results with conventional methods. Moreover, the accuracy of the FDG PET/CT by nuclear grade and histological subtypes was not significantly different.

CONCLUSION

For the surveillance of high‐risk RCC, FDG PET/CT had results that were as good as conventional methods and were not influenced by the nuclear grades of cancer cells. In addition, it was possible to examine all organ systems in one procedure, and there was no need for contrast agents, that can damage renal function. Therefore, FDG PET/CT might replace conventional methods.     

The clinical advances of fluorine‐2‐D‐deoxyglucose – positron emission tomography/computed tomography in urological cancers

Fluorine‐18 labeled fluorine‐2‐D‐deoxyglucose (FDG) is the most frequently used positron emission tomography (PET) probe but it has certain limitations when used in urological cancers. The introduction of co‐registered PET and computed tomography (PET/CT) represents a major advance in technology and FDG‐PET/CT has now become the new standard. The diagnostic performance of FDG‐PET and PET/CT depends on the metabolic activity of tumor tissue, which is generally low in primary renal cell and prostate cancers and often in their metastatic deposits. In contrast, both seminomatous and nonseminomatous germ cell tumors are characterized by upregulated glucose metabolism with subsequently increased FDG uptake in tumor sites. Generally, the metabolic activity provides accurate information regarding the presence of a viable tumor, except in patients with residual mature teratoma. Although bladder cancer demonstrates sufficiently increased FDG uptake, primary tumors are difficult to identify due to the renal excretion of FDG. The accuracy of FDG‐PET/CT in metabolically active metastases is generally higher compared to conventional CT except for identifying small lung deposits. With disease progression and subsequent de‐differentiation of prostate cancer, castrate resistant disease is more likely to present with lesions that have increased glucose metabolism.     

Bone Scan or 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography; Which Modality Better Shows Bone Metastases of Breast Cancer?

Background

In this multicenter study, we aimed to compare concurrent ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and bone scan results of breast cancer patient.

Patients and Methods

162 patients with breast cancer (158 female, 4 male; mean age 50.6 years) were included in the study. FDG PET/CT examination was performed in all patients, and concurrent bone scintigraphy in 68 patients. The results of FDG PET/CT and bone scan were compared.

Results

132 of the 162 patients were operated on because of breast cancer. 89 patients had metastasis, and 4 had recurrent disease according to FDG PET/CT results. Metastatic sites in order of frequency were lymph nodes, bone, lung, liver, adrenal gland, local skin or muscle, brain, and peritoneum (peritonitis carcinomatosa). The sensitivity, specificity, accuracy, and negative and positive predictive value of bone scintigraphy versus FDG PET/CT were 96 vs. 100%, 100 vs. 98%, 100 vs. 83%, 100 vs. 100%, and 90 vs. 100%, respectively.

Conclusion

Although the 2 modalities were in concordance with each other, in 5 (21%) cases, FDG PET/CT could not show bone metastasis which were detected on bone scintigraphy. Hence, bone scintigraphy was superior to FDG PET/CT in the determination of bone metastasis derived from breast cancer. However, FDG PET/CT should be considered for soft tissue metastasis.     

The application of positron emission tomographic imaging with fluorodeoxyglucose to the evaluation of breast disease.

Positron emission tomography (PET) is a computer-aided tomographic imaging technique that uses positron-emitting compounds to trace biochemical processes of tissue, and construct images based on them. The authors applied a whole-body PET imaging technique to patients with breast masses or mammographic abnormalities using the isotope 2-[F-18]-fluoro-2-deoxy-D-glucose (FDG), in a clinical trial to evaluate the feasibility of using PET to identify primary breast cancer, axillary lymph node involvement, and systemic metastases, before surgical resection. Fourteen patients have been entered on this study, 10 of whom proved to have breast cancer. Positron emission tomography correctly predicted the nature of 12 of the 14 primary breast lesions, and correctly determined the lymph node status of 11 of the 14 patients. The authors conclude that PET with FDG has potential as a diagnostic modality for detection of primary breast cancer, particularly in the patient with radiodense breasts by conventional mammography, and that it has potential for the preoperative identification of axillary lymph node metastases.     

肺部良性结节性病变18F-脱氧葡萄糖正电子发射体层摄影术检查

目的探讨肺部良性结节性病变18F-脱氧葡萄糖(FDG)正电子发射体层摄影术(PET)检查的显像特点.方法回顾分析1998年10月-2004年7月间的47例肺部良性结节性病变患者的FDG-PET检查资料,PET结果采用目测法判读,半定量分析法测量显影病灶的最大与平均标准摄取值(SUVmax与SUVmean)、正常肺组织的标准摄取值(SUVlung).所有患者的病变均手术切除明确诊断,其中17例结核性干酪样坏死、17例钙化及纤维化结节、6例炎性假瘤、3例新型隐球菌性肉芽肿、2例硬化性血管瘤、2例错构瘤.结果 21例病变FDG-PET检查未显影,包括钙化及纤维化结节、错构瘤以及硬化性血管瘤.26例病变或浓或淡显影,半定量分析病变组织的FDG摄取高于相应的正常肺组织(P＜0.001),SUVmax、SUVmean和SUVlung分别为3.04±1.65,2.48±1.35和0.40±0.07,其中9例(35%)患者的SUVmean与11例患者的SUVmax高于2.5;SUV与病变大小无相关性(P＞0.05).结论肺部良性结节性病变中一部分炎性结节表现为高代谢.     

18F-FDG PET/CT评价伽马刀治疗肿瘤疗效

目的探讨18F-FDG PET/CT在评价伽马刀治疗肿瘤疗效中的价值。方法对39例肿瘤术后复发患者,在伽马刀治疗前和治疗后3个月,根据CT显像的病灶大小、PET显像的平均标准摄取值（SUVmean）变化以及SUV变化率（△SUV）分别进行近期疗效判定。结果治疗前PET/CT全身检查后检出病灶并行伽马刀定位病灶65个,平均直径（3.32±3.57）cm;平均SUVmean5.92±2.62。伽马刀治疗3个月后复查,PET/CT检出病灶50个,平均直径（2.54±2.76）cm;平均SUVmean3.82±3.40。伽马刀治疗后病灶最大直径普遍较前缩小（P〈0.05）,伽马刀治疗后SUVmean显著降低（P〈0.001）。伽马刀治疗后CT显示的总有效率为38.46%（25/65）,PET SUVmean显示总有效率为55.38%（36/65）,二者之间差异有统计学意义（χ2=6.24,P〈0.05）。△SUV的总有效率为49.23%（32/65）。结论 18F-FDG PET/CT可以从病灶的大小和代谢两方面评价伽马刀治疗肿瘤的疗效。     

Utility of Preoperative 18F-FDG PET/CT and Brain MRI in Melanoma Patients with Palpable Lymph Node Metastases

Background  

The aims of this prospective study were to determine the diagnostic value of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and brain MRI in melanoma patients with palpable lymph node metastases and to assess the impact of these imaging modalities on their management.