Thoracic positron emission tomography: 18F-fluorodeoxyglucose and beyond

Ongoing technologic and therapeutic advancements in medicine are now testing the limits of conventional anatomic imaging techniques. The ability to image physiology, rather than simply anatomy, is critical in the management of multiple disease processes, especially in oncology. Nuclear medicine has assumed a leading role in detecting, diagnosing, staging and assessing treatment response of various pathologic entities, and appears well positioned to do so into the future. When combined with computed tomography (CT) or magnetic resonance imaging (MRI), positron emission tomography (PET) has become the sine quo non technique of evaluating most solid tumors especially in the thorax. PET/CT serves as a key imaging modality in the initial evaluation of pulmonary nodules, often obviating the need for more invasive testing. PET/CT is essential to staging and restaging in bronchogenic carcinoma and offers key physiologic information with regard to treatment response. A more recent development, PET/MRI, shows promise in several specific lung cancer applications as well. Additional recent advancements in the field have allowed PET to expand beyond imaging with ¹⁸F-flurodeoxyglucose (FDG) alone, now with the ability to specifically image certain types of cell surface receptors. In the thorax this predominantly includes ⁶⁸Ga-DOTATATE which targets the somatostatin receptors abundantly expressed in neuroendocrine tumors, including bronchial carcinoid. This receptor targeted imaging technique permits targeting these tumors with therapeutic analogues such as ¹⁷⁷Lu labeled DOTATATE. Overall, the proper utilization of PET in the thorax has the ability to directly impact and improve patient care.     

Prognostic value of metabolic parameters measured by pretreatment dual-time-point 18F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with intrahepatic or perihilar cholangiocarcinoma: A STROBE study

The purpose of this study was to determine the glucose metabolism at delay phase measured by pretreatment dual-time-point ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/ computed tomography (CT) provides prognostic information independent of well-known prognostic factors in patients with intrahepatic or perihilar cholangiocarcinoma (ICC or PCC).From July 2012 to December 2017, 55 patients (men 27, women 28, mean age 68 ± 11 years) with pathologically proven ICC or PCC were enrolled in this retrospective study. The dual-time-point ¹⁸F-FDG PET/CT as part of a staging workup was performed in all patients. The patient''s data includes age, sex, serum CA19-9, presence of LN or distant metastasis, early SUVmax (early maximum standardized uptake value [eSUV]), delay SUVmax (delay maximum standardized uptake value [dSUV]), retention index of SUVmax (percent change of maximum standardized uptake values [ΔSUV]), neutrophil to lymphocyte ratio (NLR) and histopathology including pCEA, p53, Ki-67 index. The analysis of the relationship between metabolic parameters and survival was done using the Kaplan–Meier curve and Cox proportional hazards regression model.Median survival for all patients was 357 days. Median early and delay SUVmax was 5.2 (range: 2.0–21.4) and 6.5 (range 2.7–24.5), respectively. The overall survival was found to be significantly related to eSUV, dSUV, ΔSUV, age, serum CA19-9 and NLR in univariate analysis. In multivariate analysis, dSUV (P = .014, 95%CI; 1.30–10.7, HR 3.74) and ΔSUVmax (P = .037, 95%CI; 1.05–6.12, HR 2.5) were independent factors of overall survival. Kaplan–Meier curve analysis clearly showed the significant difference of overall survival between 2 groups (high eSUV, low eSUV + high ΔSUV vs low eSUV and ΔSUV, P < .001) among the comparisons of the SUV parameters on FDG PET. In the receiver operating characteristic analysis using combinations of the SUV parameters, the 2 groups [eSUV + ΔSUV (P = .0001, area under the curve [AUC] 0.68) and dSUV + ΔSUV (P = .0002, AUC 0.71)] showed significantly larger AUC than the other groups applying eSUV or dSUV alone (AUC 0.61 and AUC 0.68).dSUV and ΔSUV on pretreatment dual-time-point ¹⁸F-FDG PET/CT can be useful parameters in the prediction of survival in patients with ICC or PCC.     

Value of contrast-enhanced 18F-fluorodeoxyglucose positron emission tomography/computed tomography in detection and presurgical assessment of pancreatic cancer: a prospective study

Background and Aim: Positron Emission Tomography (PET) using ¹⁸F‐fluorodeoxyglucose (FDG) associated with computed tomography (CT) is increasingly used for the detection and the staging of pancreatic cancer, but data regarding its clinical added value in pre‐surgical planning is still lacking. The aim of this study is to investigate the performance of FDG PET associated with contrast‐enhanced CT in detection of pancreatic cancer. Methods: We prospectively evaluated FDG PET/CT studies obtained in patients with suspicion of operable pancreatic cancer between May 2006 and January 2008. Staging was conducted according to a standardized protocol, and findings were confirmed in all patients by surgical resection or biopsy examination. Results: Forty‐five patients with a median age of 69 (range 22–82) were included in this study. Thirty‐six had malignant tumors and nine had benign lesions (20%). The sensitivity of enhanced versus unenhanced PET/CT in the detection of pancreatic cancer was 96% versus 72% (P = 0.076), the specificity 66.6% versus 33.3% (P = 0.52), the positive predictive value 92.3% versus 80% (P = 0.3), the negative predictive value 80% versus 25% (P = 0.2), and the accuracy 90.3% versus 64% (P = 0.085). Conclusions: Our preliminary data obtained in a limited number of patients shows that contrast‐enhanced FDG PET/CT offers good sensitivity in the detection and assessment of pancreatic cancer, but at the price of a relatively low specificity. Enhanced PET/CT seems to be superior to unenhanced PET/CT. Further larger prospective studies are needed to establish its value for pre‐surgical diagnosis and staging in pancreatic cancer.     

Contribution of 18F-fluorodeoxyglucose positron emission tomography to the diagnosis of early pancreatic carcinoma

Background/Purpose

Pancreatic carcinoma has a poor prognosis, and early detection is essential to allow potentially curative resection. Despite the wide array of diagnostic tools available, the detection of small pancreatic tumors remains difficult. The aim of this study was to investigate the contribution of ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) to the diagnosis of early pancreatic cancer.

Methods

FDG-PET was performed in 56 patients with pancreatic cancer who underwent curative surgery. The standardized uptake value (SUV) for FDG was calculated in each patient and the relationships between the SUV and various clinicopathological factors were analyzed.

Results

The tumors ranged from 0.8 to 6.5 cm in diameter. When the cutoff value for the SUV was set at 2.5, 51 of the 56 patients (91%) had a positive FDG-PET study. The SUV did not show a significant difference in relation to tumor differentiation or pTS and pT factors. There was also no correlation between the SUV and the maximum tumor diameter (r = 0.22; P = 0.1). Five tumors had an SUV below the cutoff value, and all of these lesions had intermediate or scirrhous stroma rather than medullary stroma.

Conclusions

These results indicate that FDG-PET is useful for the detection of small early pancreatic cancers.     

18 F-fluorodeoxyglucose positron emission tomography to evaluate recurrent gastric cancer: a systematic review and meta-analysis

Background and Aim: We aimed to explore the role of the diagnostic accuracy of ¹⁸F‐fluorodeoxyglucose positron emission tomography (¹⁸F‐FDG PET) in detecting recurrent gastric cancer through a systematic review and meta‐analysis. Methods: The MEDLINE, EMBASE, Cancerlit, and Cochrane Library database, from January 2001 to July 2011, were searched for studies evaluating the diagnostic performance of ¹⁸F‐FDG PET in detecting recurrent gastric cancer. We determined the sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR?), and constructed summary receiver operating characteristic curves. We also compared the performance of ¹⁸F‐FDG PET with computed tomography (CT) by analyzing studies that had also used these diagnostic methods on the same patients. Results: Across nine studies (526 patients), the overall sensitivity of ¹⁸F‐FDG PET was 0.78 (95% confidence interval [CI]: 0.68–0.86), and the overall specificity was 0.82 (95% CI: 0.76–0.87). Overall, LR+ was 3.52 (95% CI: 2.68–4.63) and LR? was 0.32 (95% CI: 0.22–0.46). In studies in which both ¹⁸F‐FDG PET and other diagnostic tests were performed, the sensitivity and specificity of ¹⁸F‐FDG PET were 0.72 (95% CI: 0.62–0.80) and 0.84 (95% CI: 0.77–0.90), respectively; of contrast CT, they were 0.74 (95% CI: 0.64–0.83) and 0.85 (95% CI: 0.78–0.90), respectively; and of combined PET and CT, they were 0.75 (95% CI: 0.67–0.82) and 0.85 (95% CI 0.79–0.90), respectively. Study sensitivity was not correlated with the prevalence of recurrent gastric cancer. Conclusion: ¹⁸F‐FDG PET has good diagnostic performance in the overall evaluation of recurrent gastric cancer, but still has some limited performance compared with contrast CT. ¹⁸F‐FDG PET combined with CT might improve the diagnostic performance in detecting recurrent gastric cancer.     

FDG-positron emission tomography/computed tomography and standardized uptake value in the primary diagnosis and staging of hilar cholangiocarcinoma

Background

The diagnosis and staging of hilar cholangiocarcinoma (HCCA) remain challenging despite recent advances in imaging. Little is known about the use of positron emission tomography/computed tomography (PET/CT) in HCCA.

Objectives

This study aimed to evaluate the additional value of FDG-PET/CT and standardized uptake value (SUV) in patients with highly suspected HCCA.

Methods

Between February 2006 and August 2009, PET/CT was performed in 30 patients with highly suspected HCCA, all of whom were deemed resectable by conventional staging methods, including laparoscopy. The results of PET-CT and SUV were compared with intraoperative and histopathological findings.

Results

The primary tumour was ¹⁸F-FDG-positive in 88% of patients. Sensitivity and specificity for the detection of regional lymph node metastases and distant metastases were 67% and 68%, and 33% and 96%, respectively. The median SUV in the primary tumour was significantly (P < 0.05) higher in patients with (mean: 8.9) than without (mean: 6.1) distant metastases. The SUV in patients with benign disease (n = 4) showed a trend towards lower values than in patients with cholangiocarcinoma, although this was not significant.

Conclusions

After conventional staging including diagnostic laparoscopy, the additional value of PET/CT is limited. This somewhat disappointing finding may reflect the fact that extensive staging studies were carried out prior to PET/CT. The SUV potentially predicts patients with distant metastases and may differentiate between HCCA and benign lesions that mimic malignancies.     

Role of 18F-fluorodeoxyglucose positron emission tomography imaging in surgery for pancreatic cancer

AIM： To evaluate the role of positron emission tomography using 18F-fluorodeoxyglucose （FDG-PET） in the surgical management of patients with pancreatic cancer, including the diagnosis, staging, and selection of patients for the subsequent surgical treatment. METHODS： This study involved 53 patients with proven primary pancreatic cancer. The sensitivity of diagnosing the primary cancer was examined for FDG-PET CT, cytological examination of the bile or pancreatic juice, and the serum levels of carcinoembrionic antigens （CEA） and carbohydrate antigen 19-9 （CA29-9）. Next, the accuracy of staging was compared between FDG-PET and CT. Finally, FDG-PET was analyzed semiquantitatively using the standard uptake value （SUV）. The impact of the SUV on patient management was evaluated by examining the correlations between the SUV and the histological findings of cancer. RESULTS： The sensitivity of FDG-PET, CT, cytological examination of the bile or pancreatic juice, and the serum levels of CEA and CA19-9 were 92.5%, 88.7%, 46.4%, 37.7% and 69.8%, respectively. In staging, FDG-PET was superior to CT only in diagnosing distant disease （bone metastasis）. For local staging, the sensitivity of CT was better than that of FDG-PEr. The SUV did not correlate with the pTNM stage, grades, invasions to the vessels and nerve, or with the size of the tumor. However, there was a statistically significant difference （4.6 ± 2.9 vs 7.8 ± 4.5, P = 0.024） in the SUV between patients with respectable and unresectable disease. CONCLUSION： FDG-PET is thus considered to be useful in the diagnosis of pancreatic cancer. However, regarding the staging of the disease, FDG-PET is not considered to be a sufficiently accurate diagnostic modality. Although the SUV does not correlate with the patho-histological prognostic factors, it may be useful in selecting patients who should undergo subsequent surgical treatment.     

~（18）F-fluorodeoxyglucose positron emission tomography in the diagnosis of small pancreatic cancer

AIM:To investigate the role of 18 F-fluorodeoxyglucose positron emission tomography(FDG-PET) in the diagnosis of small pancreatic cancer. METHODS:This study involved 31 patients with proven invasive ductal cancer of the pancreas.The patients were divided into 3 groups according to the maximum diameter of the tumor:TS1(maximum tumor size≤2.0 cm) ,TS2(>2.0 cm and≤4.0 cm) or TS3-4(>4.0 cm) .The relationships between the TS and various diagnostic tools,including FDG-PET with dual time point evaluation,were anal...     

Diagnostic role of 18F-fluorodeoxyglucose positron emission tomography for follicular lymphoma with gastrointestinal involvement

AIM:To investigate the capacity for 18F-fluorodeoxyglucose(18F-FDG) positron emission tomography(PET) to evaluate patients with gastrointestinal lesions of follicular lymphoma.METHODS:This retrospective case series consisted of 41 patients with follicular lymphoma and gastrointestinal involvement who underwent 18F-FDG-PET and endoscopic evaluations at ten different institutions between November 1996 and October 2011.Data for endoscopic,radiological,and biological examinations performed were retrospectively reviewed from clinical records.A semi-quantitative analysis of 18F-FDG uptake was performed for each involved area by calculating the maximum standardized uptake value(SUVmax).Based on the positivity of 18F-FDG uptake in the gastrointestinal lesions analyzed,patients were subdivided into two groups.To identify potential predictive factors for 18F-FDG positivity,these two groups were compared with respect to gender,age at diagnosis of lymphoma,histopathological grade,pattern of follicular dendritic cells,mitotic rate,clinical stage,soluble interleukin-2 receptor levels detected by 18F-FDG-PET,lactate dehydrogenase(LDH) levels,hemoglobin levels,bone marrow involvement,detectability of gastrointestinal lesions by computed tomography(CT) scanning,and follicular lymphoma international prognostic index(FLIPI) risk.RESULTS:Involvement of follicular lymphoma in the stomach,duodenum,jejunum,ileum,cecum,colon,and rectum was identified in 1,34,6,3,2,3,and 6 patients,respectively.No patient had esophageal involvement.In total,19/41(46.3%) patients exhibited true-positive 18F-FDG uptake in the lesions present in their gastrointestinal tract.In contrast,false-negative 18F-FDG uptake was detected in 24 patients(58.5%),while false-positive 18F-FDG uptake was detected in 5 patients(12.2%).In the former case,2/19 patients had both 18F-FDG-positive lesions and 18F-FDGnegative lesions in the gastrointestinal tract.In patients with 18F-FDG avidity,the SUVmax value of the involved gastrointestinal tract ranged from 2.6 to 17.4(median:4.7).For the 18F-FDG-negative(n = 22) and-positive(n = 19) groups,there were no differences in the male to female ratios(10/12 vs 4/15,P = 0.186),patient age(63.6 ± 2.4 years vs 60.1 ± 2.6 years,P = 0.323),presence of histopathological grade 1 vs 2(20/2 and 17/2,P = 1.000),follicular dendritic cell pattern(duodenal/nodal:13/5 vs 10/3,P = 1.000),mitotic rate(low/partly high,14/1 vs 10/3,P = 0.311),clinical stage according to the Ann Arbor system(stages ⅠE and ⅡE/other,15/7 vs 15/4,P = 0.499),clinical stage according to the Lugano system(stages Ⅰ and Ⅱ-1/other,14/8 vs 14/5,P = 0.489),soluble interleukin-2 receptor levels(495 ± 78 vs 402 ± 83,P = 0.884),LDH levels(188 ± 7 vs 183 ± 8,P = 0.749),hemoglobin levels(13.5 ± 0.3 vs 12.8 ± 0.4,P = 0.197),bone marrow involvement(positive/negative,1/8 vs 1/10,P = 1.000),detectability by CT scanning(positive/negative,1/16 vs 4/13,P = 0.335),and FLIPI risk(low risk/other,16/6 vs 13/6,P = 0.763),respectively in each case.CONCLUSION:These findings indicate that it is not feasible to predict 18F-FDG-avidity.Therefore,18FFDG-PET scans represent a complementary modality for the detection of gastrointestinal involvements in follicular lymphoma patients,and surveillance of the entire gastrointestinal tract by endoscopic examinations is required.     

氟脱氧葡萄糖F18正电子发射体层摄影术在肺癌诊断及分期中的价值

目的　探讨氟脱氧葡萄糖F18正电子发射体层摄影术(18FFDGPET)在肺癌诊断及分期中的价值。方法　94例疑诊为肺部肿瘤的患者进行了CT、18FFDGPET全身或局部检查,并对这些患者手术切除及活检的组织标本及痰液、胸腔积液的细胞标本进行了病理学检查。18FFDGPET图像分析采取单纯标准摄取值(SUV)法及目测与SUV值结合两种方法进行。SUV值法判定标准为:SUV值>25为恶性病灶,SUV值≤25为良性病灶;目测与SUV值结合法:根据病灶18FFDG摄取量与纵隔血池结构相比,并考虑SUV值、病变大小、形态及病史资料做出诊断。以病理及试验性治疗结果为确诊标准,分别计算18FFDGPET及CT在病变的定性、纵隔淋巴结转移、全身远端转移方面的敏感性、特异性、准确性、阳性预测值及阴性预测值,同时对18FFDGPETSUV值法与目测结合SUV值法的诊断效能进行比较。结果　(1)确诊情况:本组58例患者肺部病灶经组织病理学或细胞病理学检查证实为恶性;36例经病理检查或试验治疗证实为良性。(2)定性诊断:CT对肺部肿块定性诊断的敏感性、特异性、准确性、阳性及阴性预测值分别为:69%、65%、68%、82%、49%;18FFDGPET单纯SUV法分别为91%、89%、90%、93%和87%,目测+SUV值法分别为95%、94%、95%、97%和92%。(3)纵隔淋巴结转移:34例病理证实有纵隔淋巴结转移     

Incidental focal colorectal 18F-fluorodeoxyglucose uptake on positron emission tomography/computed tomography

AIM: To assess the clinical significance of incidental focal colorectal 18 F-fluorodeoxyglucose ( 18 F-FDG) uptake on 18 F-FDG-positron emission tomography/computed tomography (PET/CT). METHODS: The records of all the cases which had undergone colonoscopy after PET/CT within a two weeks interval were reviewed. Adenomas were considered advanced when they were villous, ≥ 10 mm in size, or had high-grade dysplasia. Colorectal cancers and advanced adenomas are collectively referred to as advanced colorectal neoplasms. Receiver-operating characteristic curve analysis was used to determine thesignificant predictive maximum standardized uptake value (SUVmax) cutoff value for advanced colorectal neoplasms and cancer. RESULTS: Ninety-five colorectal lesions matched the site of incidental focal colorectal 18 F-FDG uptake on PET/CT and 146 did not. Colonoscopy showed advanced colorectal neoplasms corresponding to the site of 18 F-FDG uptake in 49 of the 95 (51.5%) lesions with incidental uptake. Of the lesions without incidental uptake, only 6 of 146 (4.1%) had advanced colorectal neoplasms on colonoscopy, indicating a statistically significant difference between the two groups (P < 0.001). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of incidental focal 18 F-FDG uptake in identifying advanced colorectal neoplasms were 89.1%, 75.3%, 51.6%, 95.9%, and 78.4%, respectively. In detecting only CRC, these values were 89.2%, 69.6%, 34.7%, 97.3%, and 72.6%, respectively. The significant SUVmax cutoff value for advanced colorectal neoplasms (area under the curve 0.755, P < 0.001) was 4.35, with a sensitivity, specificity, PPV, NPV, and accuracy of 75.5%, 65.2%, 69.8%, 71.4% and 70.5%, respectively. For CRC, 5.05 was the significant SUVmax cutoff value (area under the curve 0.817, P < 0.001), with a sensitivity, specificity, PPV, NPV, and accuracy of 84.8%, 71.0%, 80.9%, 89.8%, and 75.8%, respectively. CONCLUSION: The presence of incidental focal colorectal 1     

Comparative study between endoscopic ultrasonography and positron emission tomography‐computed tomography in staging patients with esophageal squamous cell carcinoma

Treatment strategy of esophageal cancer mainly depends on accurate staging. At present, no single ideal staging modality is superior to another in preoperative tumor‐node‐metastasis (TNM) staging of patients with esophageal cancer. We aimed to investigate the efficacy of endoscopic ultrasonography (EUS) and positron emission tomography‐computed tomography (PET‐CT) for staging of esophageal cancer. We retrospectively studied 118 consecutive patients with esophageal squamous cell carcinoma who underwent esophagectomy with or without neoadjuvant chemoradiotherapy (CRT) over a near 3‐year period between January 2005 and November 2008 at a tertiary hospital in Taiwan. Patients were separated into two groups: without neoadjuvant CRT (group 1, n= 28) and with CRT (group 2, n= 90). Medical records of demographic data and reports of EUS and PET‐CT of patients before surgery were reviewed. A database of clinical staging by EUS and PET‐CT was compared with one of pathological staging. The accuracies of T staging by EUS in groups 1 and 2 were 85.2% and 34.9%. The accuracies of N staging by EUS in groups 1 and 2 were 55.6% and 39.8%. The accuracies of T and N staging by means of PET‐CT scan were 100% and 54.5% in group 1, and were 69.4% and 86.1% in group 2, respectively. In group 2, 38 of 90 patients (42.2%) achieved pathologic complete remission. Among them, two of 34 (5.9%) and 12 of 17 (70.6%) patients were identified as tumor‐free by post‐CRT EUS and PET‐CT, respectively. EUS is useful for initial staging of esophageal cancer. PET‐CT is a more reliable modality for monitoring treatment response and restaging. Furthermore, the accuracy of PET‐CT with regard to N staging is higher in patients who have undergone CRT than those who have not.     

Clinical role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in post-operative follow up of gastric cancer： Initial results

AIM： To evaluate the clinical role of 18F-fluorodeo-xyglucose positron emission and computed tomography （18F-FDG PET/CT） in detection of gastric cancer recurrence after initial surgical resection. METHODS： In the period from January 2007 to May 2008, 23 patients who had previous surgical resection of histopathologically diagnosed gastric cancer underwent a total of 25 18F-FDG PET/CT scans as follow-up visits in our center. The standard of reference for tumor recurrence consisted of histopathologic confirmation or clinical follow-up information for at least 5 mo after PET/CT examinations. RESULTS： PET/CT was positive in 14 patients （61%） and negative in 9 （39%）. When correlated with final diagnosis, which was confirmed by histopathologic evidence of tumor recurrence in 8 of the 23 patients （35%） and by clinical follow-up in 15 （65%）, PET/CT was true positive in 12 patients, false positive in 2, true negative in 8 and false negative in 2. Overall, the accuracy of PET/CT was 82.6%, the negative predictive value （NPV） was 77.7%, and the positive predictive value （PPV） was 85.7%. The 2 false positive PET/CT findings were actually chronic inflammatory tissue lesions. For the two patients with false negativePET/CT, the f inal diagnosis was recurrence of mucinous adenocarcinoma in the anastomosis in one patient and abdominal wall metastasis in the other. Importantly, PET/CT revealed true-positive findings in 11 （47.8%） patients who had negative or no definite findings by CT. PET/CT revealed extra-abdominal metastases in 7 patients and additional esophageal carcinoma in one patient. Clinical treatment decisions were changed in 7 （30.4%） patients after introducing PET/CT into their conventional post-operative follow-up program. CONCLUSION： Whole body 18F-FDG PET/CT was highly effective in discriminating true recurrence in post-operative patients with gastric cancer and had important impacts on clinical decisions in a considerable portion of patients.     

Direct comparison of 18F-fluorodeoxyglucose coincidence gamma camera tomography with gallium scanning for the staging of lymphoma

BACKGROUND: The present study compared the performance of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) using a coincidence dual-head gamma camera (FDG Co-PET) with 67gallium scinti graphy (GS) in pretreatment staging of lymphoma. METHODS: A total of 46 patients underwent FDG Co-PET, computed tomography (CT) scanning and GS for pretreatment staging of lymphoma (40 newly diagnosed and recurrence) between November 1997 and December 1999. RESULTS: Histological subgroups comprised low grade (8 patients), intermediate grade (25) high-grade (3) non-Hodgkin's lymphoma and Hodgkin's disease (10). Based on clinical assessment, CT scan findings and biopsy, 100 nodal sites and 15 extra-nodal sites were deemed positive. FDG Co-PET was superior to GS in nodal site positivity rate (97%vs 79%, P < 0.0001). Compared with GS, FDG Co-PET detected 39 more abnormal sites in 22 patients (48%), of which 28 sites were validated by biopsy, CT and/or progress FDG Co-PET scanning. There was only one proven false negative FDG site in the spleen. CT + FDG Co-PET led to upstaging in 2 patients (4%), compared to CT + GS. CONCLUSION: FDG Co-PET shows potential for providing an accurate means for pretreatment staging of lymphoma and can detect extra sites of disease activity compared to GS.     

18F-fluorodeoxyglucose positron emission tomography after definitive chemoradiotherapy in patients with oesophageal carcinoma

Background

The purpose of the study was to investigate the value of 18F-fluorodeoxyglucose-positron emission tomography performed after definitive chemoradiotherapy in patients with locally advanced oesophageal carcinoma.

Methods

Forty consecutive patients underwent 18F-fluorodeoxyglucose-positron emission tomography at baseline and after chemoradiotherapy completion. Assessment of the clinical complete response to chemoradiotherapy included oesophagoscopy plus biopsies and computed tomography scan. Cox regression analysis was used to develop the univariate and multivariate models describing the association of the independent variables with survival and local control.

Results

A clinical complete response and 18F-fluorodeoxyglucose-positron emission tomography response were present in 29 patients (72.5%) and 13 patients (32.5%), respectively. A combined response was observed in 11 patients (27.5%). During follow-up, a local failure was detected in 27.2% of patients with 18F-fluorodeoxyglucose-positron emission tomography response versus 33.3% in non-responders (p = .9). In multivariate analysis, clinical complete response (HR 5.77, p = .009) and 18F-fluorodeoxyglucose-positron emission tomography response (HR 6.27, p = .031) were identified as independent prognostic factors of overall survival.

Conclusion

In patients treated for an esophageal cancer, the present study suggested that 18F-fluorodeoxyglucose-positron emission tomography after chemoradiotherapy completion was an independent prognostic factor of overall survival without significant impact on local recurrence prediction.     

Prognostic value of dual-time-point 18F-fluorodeoxyglucose positron emission tomography in patients with pulmonary sarcoidosis

Background and objective: The value of dual‐time‐ point ¹⁸F‐FDG PET was investigated to predict the prognosis of patients with pulmonary sarcoidosis. Methods: Twenty‐one patients with pulmonary sarcoidosis underwent ¹⁸F‐FDG PET examinations at two time points: an early scan at 60 min and a delayed scan at 180 min after injection of ¹⁸F‐FDG. Standardized uptake values (SUVs) at the two time points and the retention index (RI‐SUV) calculated from these were evaluated. To evaluate disease progression, all patients underwent chest CT 1 year after ¹⁸F‐FDG PET. Using these results, the accuracy of ¹⁸F‐FDG PET parameters and ⁶⁷Ga uptake for predicting disease persistence were compared, and the correlations between those parameters and serum markers were assessed. Results: RI‐SUV was significantly higher in patients with increased or unchanged pulmonary lesions at follow‐up CT (persistent group; 21.3 ± 9.6%) than in patients with improved pulmonary lesions (improved group; ?9.2 ± 28.6%, P = 0.0075). The diagnostic accuracy of RI‐SUV in the persistent group was significantly greater than that of early SUV or ⁶⁷Ga uptake, and serum soluble IL‐2 receptor showed a significant correlation with RI‐SUV. Conclusions: RI‐SUV showed better diagnostic accuracy compared with early SUV or ⁶⁷Ga uptake, in patients with persistent lung involvement at 1 year. It may be a useful measure of persistent inflammation in patients with pulmonary sarcoidosis.     

Usefulness of 18F‐fluorodeoxyglucose positron emission tomography for diagnosis of asymptomatic giant cell arteritis in a patient with Alzheimer's disease

It is often difficult to diagnose disease in elderly patients, in particular those with dementia, who do not present with typical symptoms. This report describes our experience of an elderly patient (an 83‐year‐old woman) who presented with a chief complaint of memory loss, showed a marked inflammatory response, and was diagnosed with large‐vessel giant cell arteritis (GCA) on the basis of ¹⁸F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) findings. She had no symptoms typical of GCA including jaw claudication, visual field defect and heavy headed feeling. Corticosteroid therapy resulted in a trend toward improvement in the inflammatory response and then she first recognized that she might have experienced slight dull headache before treatment of GCA. This was probably because this patient had large‐vessel GCA, which produces a few symptoms in the head and neck, and because she had Alzheimer's disease and could not accurately describe her symptoms. Our experience suggests the usefulness of FDG‐PET for the diagnosis of GCA, particularly in elderly patients without typical symptoms. Geriatr Gerontol Int 2011; 11: 114–118.     

Advantages of 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography in detecting post cardiac surgery infections

The 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography (FDG-PET/CT) offers an excellent negative predictive value. Consequently, it is a reliable tool for excluding an infectious phenomenon in case of negativity. In case of persistent fever of unknown origin after cardiac surgery and in combination with other bacteriological examinations and medical imaging, we can rely on FDG-PET/CT to confirm or eliminate deep infections and prosthetic endocarditis. For this reason, FDG-PET/CT should be considered among the examinations to be performed in case of suspected infection after cardiac surgery. We have reported the case of a 76-year-old man who presented with a fever of unknown origin and recurrent septic shocks after a biological Bentall procedure combined with left anterior descending (LAD) coronary artery revascularization by the left internal thoracic artery. We performed a FDG-PET/CT which showed external iliac vein and right common femoral vein hyperfixation with infiltration of adjacent soft tissues, highly suspected to be an infectious process.

Learning objective

The aim of this case report is to show that FDG-PET/CT, in combination with other bacteriological examinations and medical imaging, can be extremely helpful in detecting deep infectious sources, even during the early postoperative period.     

18F-Fluorodeoxyglucose positron emission tomography computed tomography detection of single organ vasculitis of the breast: A case report

Rationale:Although single organ vasculitis (SOV) is a rare occurrence and it is difficult to diagnose, its possibility as a cause of fever of unknown origin (FUO) must be considered. Recently, the usefulness of 18F-fluorodeoxyglucose positron emission tomography computed tomography (FDG PET/CT) in the diagnosis of unknown fevers due to vasculitis, especially in cases of small and medium-sized vasculitis, has begun to be pointed out.Patient concerns:We report the case of an 84-year-old woman with persisting fever for more than 2 weeks. She had no accompanying symptoms, other than fever, and the physical examination, echocardiography, and contrast-enhanced CT did not reveal any diagnostic clue.Diagnoses:The FDG PET/CT revealed positive uptakes of FDG in the left breast, with a standardized uptake value (SUV) of 2.9. The biopsy specimen of the left breast lesion revealed rupture of the elastic plate and evidence of fibrinoid necrosis of arteries, leading to the diagnosis of polyarteritis (PAN). Further angiographic examination and additional imaging did not reveal the presence of other lesions. Therefore, the diagnosis was established as a PAN-SOV of the left breast.Interventions:This patient has improved with follow-up only.Outcomes:There has been no evidence of a relapse of PAN over a 5-year follow-up period.Lessons:SOV presenting with unspecific local symptoms is difficult to diagnose based on the medical history and clinical examination. Our findings show that early “Combination of PET-CT and biopsy” can be a powerful diagnostic tool in patients with FUO for whom diagnosis of the underlying cause is difficult despite appropriate clinical examination.