Search

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome involving an uncontrolled immune response with variable triggers. HLH is rare but highly fatal, even with proper treatment; therefore, early recognition and diagnosis are crucial for management. Although the role of F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in HLH is poorly defined, it can provide valuable information on disease status and possible triggers. Herein, we report an F-18 FDG PET/CT study on a case of NK/T-cell lymphoma that progressed from Epstein-Barr virus-associated HLH.

The appearance of residual disease in F-18-FDG-PET/CT after radiotherapy (RT) in non-small cell lung cancer (NSCLC) is associated with worse survival. The aim of this study was to demonstrate the corresponding subvolume of tumours in pre-RT F-18-FDG-PET/CT (PET1) in patients in whom residual tumour was seen in post-RT F-18-FDG-PET/CT (PET2) after definitive RT/chemoradiotherapy (CRT). Patients with inoperable stagel-IIINSCLC and who received chemoradiotherapy and/or radiotherapy alone and had residual tumour in PET2 were included. After matching the SUV threshold (70%, 80%, and 90%) delineated image seen in PET2 with PET1, we manually increased the tumour threshold of volume of interest (VOI) in PET1. We found which SUV threshold (70%, 80%, 90%) delineated VOI in PET2 corresponded to which tumour subvolume in PET1. Thirty patients were included in the analysis. The median subvolume threshold corresponding to a SUV threshold of 70% VOI in PET2 was 50% (range, 40-65%). The mean SUV subvolume threshold in PET1 corresponding to an 80% SUV threshold VOI in PET2 was 56.3 +/- 7.5% (range, 40-70%). The mean SUV subvolume threshold in PET1 corresponding to a 90% threshold VOI in PET2 was 64.5 +/- 7.5% (range, 50-80%). Pre-RT F-18-FDG-PET/CT can predict high-risk subvolumes for residual disease after radiotherapy. Threshold values of SUVmax 50%, 56.3%, and 64.5% corresponded to high risk areas for residual disease in pre-RT 18F FDG PET/CT.

Objective This study aimed to examine the diagnostic performance of F-18 fluorodeoxyglucose positron emission tomography with computed tomography (F-18 FDG PET/CT) compared with cancer antigen 125 (CA125), human epididymis protein 4 (HE4), and risk of ovarian malignancy algorithm (ROMA) score to distinguish epithelial ovarian cancer from benign tumors. Methods A total of 46 patients with pelvic masses, who underwent F-18 FDG PET/CT, CA125, and HE4 before surgery between January 2015 and December 2018, were included in this retrospective study. The diagnostic performance of CA125, HE4, ROMA score, and maximum standardized uptake value (SUVmax) to differentiate epithelial ovarian cancer from benign pelvic tumors was examined by receiver operating characteristic curve analysis. Results Among the 46 patients, 28 were cases of ovarian cancers and 18 were of benign. The mean values of CA125, HE4, ROMA score, and SUVmax were significantly higher in the ovarian cancer group than the benign group. In early cancer stages (stages I and II), Area under the curve for SUVmax was significantly higher than CA125 and ROMA score (0.778 for CA125, 0.753 for HE4, 0.682 for ROMA score, and 0.922 for SUVmax). Conclusion SUVmax using F-18 FDG PET/CT showed a high diagnostic accuracy for differentiating epithelial ovarian cancer from benign pelvic tumors, including early stage ovarian cancer. F-18 FDG PET/CT can be a useful modality for the assessment of pelvic mass. .

Purpose This retrospective study aimed to analyzed the F-18 fluorodeoxyglucose PET/computed tomography (F-18 FDG PET/CT) features of pulmonary sclerosing pneumocytoma (PSP) to improve the understanding and preoperative diagnostic efficacy of this rare disorder. Methods FDG PET/CT images from 11 patients with 22 lesions (including one patient with 12 lesions) proven PSP in our hospital were reviewed. We summarized the PET/CT features of PSP and analyzed the correlation between FDG uptake and tumor size. Results PET/CT imaging revealed all tumors located in each lobe of the two lungs randomly. All 22 tumors were round or oval nodules; 15 had smooth margins, six were lobulated, six were calcified, and one had a ground-glass halo sign. The mean diameter of these tumors was 19.2 ± 7.8 mm (range: 8-34 mm); the mean maximum standardized uptake value (SUVmax) was 2.8 ± 1.3 (range: 1.1-7.4). Sixteen of the lesions exhibited mild to moderate FDG uptake (mean SUVmax 2.3 ± 0.6), and six of the lesions exhibited intense FDG uptake (mean SUVmax 4.3 ± 1.6). A positive correlation was observed between FDG uptake and tumor size (P Conclusion Single round or ovoid soft-tissue lesions with smooth margins, and mild to moderate FDG uptake on PET/CT images in middle-aged females, suggest a possible diagnosis of PSP. For some atypical cases with intense FDG uptake, a diagnosis of PSP also can be considered. A statistically significant positive correlation was found between SUVmax and PSP lesion size in our study.

Objectives To evaluate the feasibility of radiofrequency ablation (RFA) on follicular neoplasm with low standard uptake value (SUV) in a Positron emission tomography (PET/CT) study. Methods From January 2018 to July 2019, 86 consecutive patients were diagnosed with follicular neoplasm. Of the patients, 28 with PET/CT scans were enrolled in this study. All patients received ultrasound, fine/core needle aspiration, and PET/CT scan prior to treatment. In accordance with previous studies, we recommended 6 patients who had follicular neoplasm with SUVmax ≥5 undergo surgical resection due to an elevated suspicion of malignancy. For 22 patients SUVmax

Positron emission tomography (PET) is a tomographic imaging method that shows three-dimensional distribution of radiopharmaceuticals which are labelled with positron emitter radionuclides. Today most widely used PET radiopharmaceutical F-18 flourodeoxyglucose is an F-18 labelled glucose analogue, and it is trapped by membrane glucose transporters to viable cells. F-18 fluorodeoxyglucose (FDG) uptake is proportional to glucose consumption of the tissue. In several type of cancers, increased glucose consumption is seen due to increased GLUT expression and hexokinase activity. F-18 FDG PET is a proved sensitive method in the diagnosis, staging, restaging and treatment response evaluation for several oncological disease. This practice guideline aims to help nuclear medicine physicians, physicists and technicians as persons who apply, evaluate and report F-18 FDG PET/CT by providing general information of F-18 FDG PET/CT. Additionally it is focused to provide standardization of quality of diagnostic imaging and harmonization of obtained quantitative information.

Aim: To evaluate the diagnostic performance of F-18 FDG PET/CT for the detection of local and distant disease relapse in treated patients with cervical carcinoma. Materials and Methods: This retrospective study includes 43 patients with pathologically proven cervical carcinoma, 36 patients were pathologically proven as Squamous Cell Carcinoma (SQ.C.C.) and 7 were adenocarcinoma. They received initial treatment and with clinico-laboratory suspected recurrence. They referred to nuclear medicine unit, to perform F-18 FDG PET/CT study. Sites of the relapse (classified as positive or negative) were categorized into local and distant recurrence. The final diagnosis of disease status was made on subsequent follow up by conventional imaging (CT/MRI), F-18 FDG PET/CT, or histopathology whenever possible.Results: 34 (79.1%) of the patients were proven to have loco-regional &/or distant recurrence based on histopathology & or follow up. F-18 FDG PET/CT changed management in 8 patients (18.6% of the group). On per patient based analysis for detection of loco-regional and distant recurrence, F-18 FDG PET/CT, outperformed Ce-CT alone as regards the sensitivity indices with NPV 88.89% for F-18 FDG PET/CT compared to 66.67% for Ce-CT alone.As regards loco-regional recurrence, and on per lesion based analysis, statistically higher sensitivity and NPV were seen with F-18 FDG PET/CT of 100% exceeding those of Ce-CT alone(SN 71.11% & NPV 80.6%) with P-value 0.0001 & 0.002 respectively, with overall diagnostic accuracy reached 98.06% with F-18 FDG PET/CT compared to 83.5% with Ce-CT (P-value 0.017). Distant metastases were also analyzed on per lesional basis where PET/CT revealed higher sensitivity and specificity indices compared to Ce-CT, with sensitivity, specificity, NPV and overall accuracy were 97.92%, 83.33%, 89.29%, & 95.4% respectively compared to 82.64%, 66.67%, 44.44%, 79.89%, for Ce-CT respectively with P-value

Assessing response to treatment is an important parameter in oncology practice and there is a growing body of evidence for use of F-18 fludeoxyglucose (FDG) positron emission tomography/computerized tomography (PET/CT) to evaluate response during or after the treatment. The use of FDG PET/CT for this indication is increasing due to its advantages such as enabling rapid evaluation of all lesions and body parts in a single session, assessing viability in residual masses, not being limited to size measurements and low inter-observer variability. Many evaluation criteria have been proposed for standardization and interpretation of PET/CT findings. This guideline aims to provide a brief overview of proposed criteria and assist Nuclear Medicine Physicians in interpreting FDG PET/CT findings for the evaluation of the response.

Histologic confirmation of cardiac sarcoidosis (CS) is challenging. When taken into account of either the invasive nature or potential false negativity of the endomyocardial biopsy, imaging methods represent as a major alternative to establish a clinical diagnosis. Among the imaging methods, the use of fluorine-18-fluorodeoxyglucose (F-18 FDG) positron emission tomography/computed tomography (PET/CT) which detects active inflammation in CS is becoming widespread. Recently, F-18 FDG PET has been identified as one of the new diagnostic criteria in CS, by the Heart Rhythm Society. For diagnosis, a combination of both myocardial perfusion and inflammation findings should be interpreted visually and/or semiquantitatively. Yet, the precision of diagnostic accuracy has been limited by lack of an adequate reference standard. This procedure guideline presents current literature defining the role of F-18 FDG PET in the diagnosis and management of CS along with technical details and recommendations about imaging protocol and interpretation.

We present a rare case of primary diffuse large B-cell lymphoma of the thoracic vertebra in a patient with metastatic lung cancer.

Objective We investigated the role of Ga-68 DOTATATE PET/CT in comparison to F-18 FDG PET/CT in patients with low and intermediate versus high-grade neuroendocrine tumors (NETs). Methods We identified 81 patients who underwent Ga-68 DOTATATE PET/CT at our institution between May 2017 and December 2018 and met inclusion criteria of biopsy-proven NET with known Ki-67 index, histologic grade, or differentiation. Patients were divided into two groups. Control group included Ki-67 ≤20%, grade 1 or 2, or well-differentiated tumors. Experimental group included Ki-67 >20%, grade 3, or poorly-differentiated tumors. Results Mean age was 57 years, with 36 males and 45 females. Most common primary sites were small bowel, pancreas, and lung. Most common distant metastatic sites were liver and bone. In the control group (n = 67), median Ki-67 was 4% (range 1-30%). 55/67 (82.1%) DOTATATE and 6/11 (54.5%) FDG scans were positive (P = 0.04). Positive scans showed >10 lesions in 25/55 (45.5%) DOTATATE and 1/6 (16.7%) FDG scans (P = 0.18). 40/55 (72.7%) positive DOTATATE and 3/6 (50%) FDG scans showed distant disease (P = 0.25). In the experimental group (n = 14), median Ki-67 was 68% (range 25-95%). All 14 DOTATATE and all nine FDG scans were positive. Positive scans showed >10 lesions in 4/14 (28.6%) DOTATATE and 5/9 (55.6%) FDG scans (P = 0.20). 10/14 (71.4%) positive DOTATATE and 7/9 (77.8%) FDG scans showed distant disease (P = 0.74). Conclusion All patients with high grade, poorly-differentiated NETs had positive DOTATATE PET/CTs. In these patients, DOTATATE PET/CT did not significantly differ from FDG PET/CT in identifying >10 lesions or distant disease.

Aim: To evaluate the prognostic value of the initial quantitative PET/CT parameters in terms of therapy response and survival in patients with esophageal carcinoma. Material &methods: This retrospective study includes thirty-two patients (17 males and 15 females). All patients had pathologically proven esophageal cancer. These Patients underwent whole body 18F-FDG PET/CT as a baseline staging method before Neoadjuvant therapy. Initial FDG PET/CT scans were retrieved and PET volumetric images were analysed for metabolic parameters including maximum SUV (SUV max), mean SUV (SUV mean), (SUV peak), MTV and TLG. Results: 53.1% of the enrolledpatients were males and 46.9%were female with the dominating pathological subtype was Squamous cell carcinoma in 20 patients (62.5%). Quantitative analyses of the metabolic parameters of the enrolled patients revealed SUV max with average value 16.13 +/- 8.71, SUV mean with average value 9.47+/- 5.2, SUV peak with average value 13.09 +/-7.1. MTV with average value 32.5+/-21.88 and TLG with average value 332.44+/- 318 and range between (34 and 1149). Survival analysis showed that initial SUV max, SUV mean, SUV Peak of oesophageal tumour were not correlated with OS. While MTV and TLG were correlated with OS with p value of 0.045 and 0.031 respectively. Conclusion: The initial PET/CT MTV and TLG metabolic parameters are prognostic parameter for response and survival ismore efficient than the other metabolic parameters in patients with esophageal cancer.

Mesenteric panniculitis is a relatively rare fibro-inflammatory condition of the mesentery. In acute phase, it demonstrates avid uptake on Fluorine-18 FDG PET/CT (PET/CT). Thorough assessment is needed to differentiate from viable or recurrent disease in patients with malignant lymphoma because it mimics active lymphomatous disease on PET/CT. In this article, 3 illustrative cases of malignant lymphoma are presented. PET/CT demonstrated new FDG-avid mesenteric lesions at the end-of-treatment evaluation while the original disease showed significant response. Early recurrence was initially suspected, but together with clinical course and findings, active surveillance was opted. Sequential follow-up PET/CTs showed various patterns of metabolic activity over time; it can persist for months or more, or metabolic activity can fluctuate over time. Eventually benignity was confirmed in these cases. These cases underscore the importance of interpretation with clinical context and awareness of chronological metabolic changes of mesenteric panniculitis to determine proper management.

Scrub typhus is an acute febrile illness caused by obligate intracellular organism Orientia tsutsugamushi. While there have been many reports on the evaluation of disease activity and infectious diseases using F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT), the clinical value of FDG PET/CT in scrub typhus has not been fully investigated. We enrolled 17 patients who were 18 years of age or older and clinically suspected of having scrub typhus with eschar. Clinical assessments, blood samples, and FDG PET/CT images were obtained at enrolment and again after 3 weeks. The median age of the patients was 65 years; 9 (52.9%) patients were male. On initial FDG PET/CT, the eschars showed markedly increased FDG uptake on PET imaging that improved after treatment. Generalized lymphadenopathy and splenomegaly with high FDG uptake were observed in all patients. On follow-up FDG PET/CT after appropriate therapy, FDG uptake and sizes of eschar, lymph nodes, and spleen were markedly decreased. As far as we are aware, this is the first investigation with multiple patients of FDG PET/CT in scrub typhus and the demonstration of clinical utility. FDG PET/CT imaging of scrub typhus could provide useful information about the clinical features before and after antibiotic treatment.

BACKGROUND. Multiple studies have demonstrated that when incorporated with conventional imaging modalities, cardiac F-18 PET/CT can aid in diagnosis of endocarditis and improve the sensitivity of the Duke Criteria. These studies used as their gold standard the opinion of an endocarditis team and were characterized by low percentages of patients who underwent surgery. We reviewed 4 years of surgically managed IE cases where F-18 cardiac PET/CT was used to aid diagnosis. METHODS. Between July 2014 and December 2018, we retrospectively reviewed 68 surgically managed endocarditis cases to identify patients who underwent pre-operative PET scans. RESULTS. Fourteen patients were identified who underwent F-18 cardiac PET/CT prior to surgical intervention. Nine cases were classified as possible endocarditis by Duke Criteria and 8 involved prosthetic valves. Twelve out of fourteen scans were interpreted as suggestive of or consistent with endocarditis based on FDG uptake. Twelve positive PETs were associated with either operative findings of infection and/or positive PCR testing on the excised valve. Two patients with negative scans were found to have non-infectious mobile masses intra-operatively, negative valve cultures and negative pathology. CONCLUSION. In a small cohort, F-18 FDG cardiac PET/CT correlated closely with intra-operative findings in patients with endocarditis and helped guide surgical decision-making. It could be considered for addition to the Duke Criteria in the American Heart Association endocarditis guidelines similar to European protocols.

Our purpose was to determine the frequency, determinants, and costs of recommendations for additional imaging (RAIs) in clinical F-18-FDG PET/CT reports. Methods: This retrospective study included a random sample of 2,643 F-18-FDG PET/CT scans that were performed for various clinical reasons at a tertiary-care academic medical center without financial incentives for self-referral, within a 1.5-y period. Results: Ninety-eight (3.7%) of 2,643 F-18-FDG PET/CT reports contained an RAI. None of the investigated variables (patient age, hospital status [inpatient or outpatient], indication for F-18-FDG PET/CT scanning [oncologic, infection/inflammation, or miscellaneous], type of F-18-FDG PET/CT scan [low-dose F-18-FDG PET/CT or low-dose F-18-FDG PET/CT combined with diagnostic CT of any body region], or years of experience of the [most senior] signing author) was univariately associated with the presence of an RAI in the F-18-FDG PET/CT report. The hypothesis that RAIs more frequently occur when the anatomic area to which the RAI relates is not covered by a diagnostic CT scan (as part of the F-18-FDG PET/CT examination) was also rejected (P = 0.419). The total costs of all RAIs (regardless of whether they were actually performed by the referring clinicians) were (sic)23,922.21 ($27,065.47), which corresponds to an average of (sic)9.08 ($10.27) RAI costs per F-18-FDG PET/CT exam. The total costs of all RAIs that were actually performed by the referring clinicians were (sic)16,498.62 ($18,666.46), which corresponds to an average of (sic)6.26 ($7.08) RAI costs per F-18-FDG PET/CT exam. Conclusion: RAIs in F-18-FDG PET/CT reports in a European tertiary-care academic medical center without financial incentives for self-referral are infrequent, cannot be anticipated, and result in relatively low overall costs.

Objectives The aim of this study was to compare the quantitative value of standardized uptake value (SUV) SUVmax obtained from F-18 FDG positron emission tomography/computed tomography (PET/CT) imaging of oncology patients with the cell-free DNA (cfDNA) amounts measured in plasma of patients and thus investigate if cfDNA is a significant marker to identify the presence of malignancy in the early period. Methods A total of 184 patients were included in the study. The clinical, histopathologic, laboratory and treatment parameters were extracted from patient files. SUVmax and cfDNA quantities were assessed Results There was no statistically significant difference in plasma cfDNA values between patient and control groups. The comparison of SUVmax and cfDNA values in the study showed that there was a weak correlation between SUVmaxand cfDNA. There was a significant difference between tumor size and SUVmax values. However, there was no statistically significant difference between tumor size and cfDNA. Conclusion cfDNA measurements in the blood as a screening test have provided hope for early diagnosis and monitoring of cancer patients. Comparison of cfDNA levels obtained from plasma and quantitative parameters from PET/CT images of oncology patients in detailed advanced studies with larger patient series are required.

Intrapulmonary solitary fibrous tumors (SFTs) are extremely rare neoplasms. We report a case of an intrapulmonary SFT and describe the findings of computed tomography (CT) and F-18 fluorodeoxyglucose positron emission tomography. The case indicates that a benign intrapulmonary SFT can present as a ground-glass nodule in the early stages of disease and may appear as a well-defined, lobular, homogeneously enhanced mass with slow growth on chest CT images. To our knowledge, this is the first report describing the natural course of an intrapulmonary SFT over 16 years based on the findings of chest CT and F-18 fluorodeoxyglucose positron emission tomography/CT. Keywords: Solitary fibrous tumor (SFT), Intrapulmonary, Computed tomography (CT)

Introduction:Decompressive craniectomy (DC) is commonly used as the treatment for refractory intracranial hypertension. The indications for cranioplasty after DC are cosmetic repair and, mainly, restoration of cerebral protection. Unexpected improvement in patient’s neurological status has been observed among patients that underwent cranioplasty. This study was conducted to determine the impact of cranioplasty on cerebral metabolism and its correlation with clinical outcome.Methods:Twelve patients who underwent DC for various reasons underwent positron emission tomography/computed tomography (PET/CT) with F-18 labeled fluorodeoxyglucose (FDG) before and after cranioplasty.Results:There were 11 (92%) male patients and 1 (8%) female patient in the study. The mean age was 46.8±14.1 years. The most common indication was trauma (58%), while the most frequently affected side was right (67%). The cerebral metabolism evaluated by FDG-PET/CT was found to be significantly decreased in the hemisphere ipsilateral to the trauma compared with the contralateral hemisphere (3.87 vs 2.72, p=0.012). All patients showed improvement in one or more anatomic areas with cranioplasty (median: 6, minimum: 3, maximum: 8). Cranioplasty did not cause a significant change in FDG uptake in both hemispheres (ipsilateral p=0.814, contralateral p=0.308). Nevertheless, a general improvement and decrease in symptoms were observed in all patients before and after cranioplasty.Conclusion:Though we are unable to demonstrate a significant increase in the cerebral metabolism, cranioplasty was observed to have a therapeutic role in terms of clinical outcome improvement.

Introduction:F-18 radioisotope has higher photon energy when compared with other radioisotopes that are preferred in conventional imaging procedures in nuclear medicine. The aim of this study was to measure external radiation dose rate from patients injected with F-18 fluorodeoxyglucose (FDG) and to determine appropriate discharge time after F-18 FDG positron emission tomography/computed tomography (PET/CT) procedure.Methods:Our study included 29 (M/F=9/20) patients who were referred to nuclear medicine department for F-18 FDG PET/CT imaging. Dose rates were measured at a distance of 0, 0.5, 1, 1.5 and 2 m from patients via Geiger-Müller probe at 3 different time points: 1) Just after the intravenous injection of F-18 FDG, 2) before PET/CT imaging and 3) just before discharge of patients from PET/CT department. Statistical analysis was performed to evaluate the differences between measurements.Results:Patients were injected 291±62 megabecquerel (MBq) (range: 226-440 MBq) F-18 FDG via IV route. The patients stayed in nuclear medicine department for 70.3±13.8 min (range: 53 min-100 min) after injection of F-18 FDG. Radiation dose velocity measurements taken at a distance of 1 meter were 39.7±11.9 μSv/h just after the injection, 21.1±4.5 μSv/h before PET/CT examination and 14.3±2.9 μSv/h just before discharge.Conclusion:Although F-18 has high photon energy, its halflife is relatively short and this makes F-18 FDG an ideal radiopharmaceutical for PET/CT imaging. When the PET/CT scan is terminated, the dose rate measurements of the patients at a distance of 1 m are appropriate for discharge according to Turkish Atomic Energy Authority regulations. Therefore, patients can be safely discharged by explaining the necessary radiation safety measures after completing F-18 FDG PET/CT imaging.

We report a case of a patient with locally advanced prostate cancer who had only lymph node involvement without bone metastasis on F-18 FDG PET/CT. A 62-year-old Korean male was admitted to our hospital due to dysuria. His PSA level on admission was 79.35 ng/mL. A transrectal ultrasound-guided prostate biopsy confirmed prostate cancer and his Gleason score was 10 (5+5). F-18 FDG PET/CT demonstrated a hypermetabolic mass lesion with SUVmax 7.0 in the prostate and hypermetabolism with SUVmax 4.7 of the abdominal and pelvic lymph nodes. Tc-99m HDP bone scan showed no significant bone metastasis. The patient underwent hormonal therapy for 9 months. Follow-up F-18 FDG PET/CT showed significantly reduced size and FDG uptake in the prostate and abdominal and pelvic lymph nodes. In this case, treatment monitoring with F-18 FDG PET/CT showed decreased mass size and FDG uptake in the prostate and abdominal and pelvic lymph nodes.

Background: The aim of the present study was to investigate the added value of F-18 fludeoxyglucose (FDG) positron-emission tomography (PET)/computed tomography (CT) compared with conventional imaging modalities for the evaluation of locoregional and distant sites of recurrence in breast cancer patients. Methods: From May 2013 to September 2016, 109 patients with suspected recurrent breast cancer who underwent conventional imaging and F-18 FDG PET/CT with an interval of 6 weeks were consecutively enrolled (mean age: 52.66 years; range: 29?79). Histopathologic results and clinical follow up based on the gold-standard imaging modality or serial imaging were considered as the reference for verification of F-18 FDG PET/CT findings. Results: Of 109 patients, 81 were found to have at least one site of recurrence (74.31%). Local recurrence was correctly identified in 32/32 patients following PET/CT, which was higher than that on conventional imaging (20/32, 62.5%). PET/CT detected 27 additional nodal metastases compared with conventional imaging (59 vs. 32, 45.76%), most frequently in the hilar/mediastinal region (n=27), followed by the supraclavicular lymph nodes (n=20, 62.5%), internal mammary lymph nodes (n=6, 18.77%), and axillary basin (n=6, 18.77%). Additional sites of distant metastasis were identified in 41 patients (37.61%) following F-18 FDG PET/CT imaging, 48.78% of which were localized in the skeletal system (n=20), 21.95% in the liver (n=9), 12.19% in the lungs (n=5), 12.19% in the brain (n=5), and 4.87% in the adrenal glands (n=2). Conclusion: F-18 FDG PET/CT serves as a useful supplement to conventional imaging techniques by identifying additional sites of disease recurrence in patients with breast cancer, which may change the preferred treatment strategy, particularly in regions that are not routinely evaluated by conventional imaging.

Histoplasmosis is a common fungal infection in endemic countries including Malaysia. Although it is commonly diagnosed in immunosuppressed individuals, there is a preponderance of immunocompetent individuals among individuals with disseminated disease involving adrenal gland. There is a diagnostic dilemma in most patients as the clinical presentation, biochemical parameters and imaging features are frequently non-specific. On 18F-FDG PETCT, histoplasmosis shows high FDG avidity. However, due to overlapping features with other disease conditions, tissue biopsy remains as the confirmatory test. In this report, we present a case of disseminated histoplasmosis with high FDG uptake in the adrenal glands and lymph nodes which mimic a metastatic cancer.

Funding Acknowledgements Type of funding sources: None. Background Myocardial inflammation may occur in the context of a multisystem disease such as sarcoidosis, adversely affecting prognosis. A definitive diagnosis of cardiac sarcoidosis (CS) is essential to implementing life-saving treatment but this is complicated by the invasive nature of endomyocardial biopsy (EMB) and its low accuracy. Positron emission tomography (PET) assists in diagnosis, which relies on visual interpretation of myocardial F-18 FDG uptake. The value of quantitative analysis and its application to clinical practice remain uncertain. Purpose To investigate the power of quantitative F-18 FDG PET-CT imaging analysis for detecting CS in patients with suspected disease. Methods All patients underwent F-18 FDG PET-CT after a 24-hour low-carbohydrate diet and 15-hour fasting as part of their diagnostic work-up for suspected cardiac inflammation. Cardiovascular magnetic resonance acted as gatekeeper to PET-CT in 8 of every 10 scans. Myocardial F-18 FDG uptake was assessed qualitatively and quantitatively using both manually drawn regions of interest and automatic polar maps to measure global and segmental standardised F-18 FDG uptake values (SUV). The coefficient of variation (CoV) was calculated to determine uptake heterogeneity. To confirm diagnosis, follow-up data regarding disease progression, further testing and treatment were collected. To allow for sufficient follow-up time, the first 40 consecutive patients from a prospective registry (n= 214; Sep 2017-Jun 2020) were included. Results A comprehensive clinical picture was obtained successfully in 37 patients (median [IQR], 17 [13.5] months) and a final diagnosis of CS reached in 7 (disease prevalence, 19%). EMB was performed in 2 patients only while 3 underwent PPM/ICD implantation. Significant predictors of CS were fulfilment of Japanese Ministry of Health and Welfare criteria (Wald, 6.44; p = 0.01) and left ventricular dysfunction (Wald 6.72; p = 0.01). Qualitative F-18 FDG PET-CT had a high negative (95%) but low positive (45%) predictive value for CS (sensitivity, 83%; specificity, 77%). F-18 FDG SUV CoV was the strongest imaging predictor (Wald, 6.77; p = 0.009) and was significantly higher in CS than non-CS (CoV median [quartiles], 0.26 [0.21, 0.36] and 0.12 [0.11, 0.14] respectively; p = 0.004). As per ROC curve analysis (AUC, 0.84), a CoV threshold of 0.20 was highly specific (93%) and sensitive (86%) for CS. Conclusion In a referring population with a low prevalence of cardiac sarcoidosis, F-18 FDG PET-CT imaging is sensitive for the detection of myocardial inflammation with active disease unlikely in patients with a negative scan. Quantitative evaluation of metabolic heterogeneity within the myocardium provides a strong, independent marker of active disease and should be considered alongside visual assessment.

Objectives The present study aimed to investigate the diagnostic performance of F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the detection of bone marrow involvement (BMI) in paediatric Hodgkin lymphoma (HL) through a systematic review and meta-analysis. Methods PubMed, Cochrane, and EMBASE databases were searched from the earliest available date of indexing till March 31, 2020 for studies evaluating the diagnostic performance of F-18 FDG PET/CT in the detection of BMI in paediatric HL. Results Across seven studies (1265 patients), the pooled sensitivity of F-18 FDG PET or PET/CT was 0.95 (95% confidence interval [CI]: 0.87–0.98) with heterogeneity (I2 = 86.2, p Conclusions The present meta-analysis revealed high sensitivity and specificity of F-18 FDG PET/CT for the detection of BMI in paediatric HL. Currently, the literature regarding the use of F-18 FDG PET/CT for the detection of BMI in paediatric HL is limited. Large multicentre studies are necessary to substantiate the diagnostic accuracy of F-18 FDG PET/CT in the detection of BMI in paediatric HL. Advances in knowledge Through a meta-analysis, this study provided a more reliable assessment of the diagnostic utility of F-18 FDG PET/CT, which exhibited good diagnostic accuracy in the detection of BMI in paediatric HL.

Background Positron emission tomography (PET) findings for gliomatosis and lymphomatosis have been rarely reported. Purpose To compare PET/computed tomography (CT) findings using 11C-methionine (MET) from PET/CT findings using 18F-fluorodeoxy glucose (FDG) for patients with lymphomatosis or gliomatosis of the brain. Material and Methods Participants comprised all 10 patients with lymphomatosis or gliomatosis of the brain treated at our institution in the past 12 years. Underlying pathologies comprised intravascular lymphoma (n = 1), lymphomatosis (n = 3), and gliomatosis (n = 6). All cases were pathologically diagnosed. In seven patients, both MET-PET/CT and FDG-PET/CT were performed simultaneously in a single study. In three patients, only FDG-PET/CT was performed. The degree of tracer accumulation to the lesion was evaluated qualitatively. Quantitatively, the ratio of maximum standard uptake value (SUVmax) in tumor to that in normal tissue (T/N ratio) was measured and compared between FDG and MET. Results Qualitatively, MET accumulated to part of the lesion in six of seven patients and almost all of the lesion in one in seven patients. FDG accumulated to part of the lesion in three of ten patients and almost all of the lesion in one of ten patients. No FDG accumulation was seen in the lesion in six patients. Quantitatively, mean ± SD T/N ratio was significantly higher with MET (2.11 ± 0.63) than with FDG (1.18 ± 0.84; P Conclusion In lymphomatosis and gliomatosis, FDG accumulates in only part of the lesion. FDG is thus less suitable than MET for depicting these lesions.

Introduction Multiple myeloma (MM) is a potentially incurable haematological malignancy with devastating manifestations including lytic bone lesions leading to fractures and renal insufficiency. As a disease of patients with a mean age of 66 years, both the disease and the continuous efforts of treatments lead to frailty and devastation. From this stand point, we aimed to evaluate the development of muscle loss in MM patients and also with a new method of sarcopenia evaluation, F-18 FDG PET/CT. While used for bone disease routinely, this method brings a fresh perspective of metabolic quantitation of alteration of muscles which may be regarded as muscle quality. Materials and methods Data and images of 105 patients with MM both before and after treatment were evaluated in a retrospective manner. Results Both female and male patients were observed to be effected after MM treatment in terms of lumbar and femoral muscle evaluations with CT. Metabolic evaluations confirmed a loss of quality in muscles in terms of metabolic volume and total lesion glycolysis. Conclusion Sarcopenia should be evaluated in every patient and regarded as a treatment target. FDG PET/CT is an easy and handy tool to assess muscle mass and quality as well as MM disease status.

Objectives The aim of the present review was to assess the role of combined 18F-Fluorodeoxyglucose (F-18 FDG) and Ga-68 DOTA-peptides positron emission tomography (PET)-computed tomography (CT) in neuroendocrine tumors (NETs). Methods We have searched MEDLINE databases, including PubMed and Scopus, for studies about the combined FDG and Ga-68 DOTA-peptides PET-CT or PET/Magnetic Resonance Imaging (MRI) in NETs in the last 15 years (from 2004 to November 2019). No limits were applied to the search strategy. Abstracts, reviews, letters to editors, and editorials were excluded. Results Seven studies met the inclusion criteria. In total 236 patients received both 68Ga-DOTA-peptides and F-18 FDG PET-CT for the characterization of NETs. In particular, 84 patients had a neuroendocrine lung tumor while the others mainly a gastroenteropancreatic NET. The combined use of F-18 FDG and Ga-68 DOTA-peptides (mainly TOC) PET studies provides complementary information regarding different biological characteristics of the lesions, thus enabling a more accurate selection of patients for targeted radionuclide therapy and a better stratification of the prognosis. Conclusions Ga-68 DOTA-peptides and F-18 FDG PET should be considered complementary in patients with NETs. They should be both performed in the initial staging and during follow-up, with a specific selection of patients and in a multidisciplinary vision.

International audience; In the latest update of the European Society of Cardiology (ESC) guidelines for the management of infective endocarditis (IE), imaging is positioned at the centre of the diagnostic work-up so that an early and accurate diagnosis can be reached. Besides echocardiography, contrast-enhanced CT (ce-CT), radiolabelled leucocyte (white blood cell, WBC) SPECT/CT and [F-18]FDG PET/CT are included as diagnostic tools in the diagnostic flow chart for IE. Following the clinical guidelines that provided a straightforward message on the role of multimodality imaging, we believe that it is highly relevant to produce specific recommendations on nuclear multimodality imaging in IE and cardiac implantable electronic device infections. In these procedural recommendations we therefore describe in detail the technical and practical aspects of WBC SPECT/CT and [F-18]FDG PET/CT, including ce-CT acquisition protocols. We also discuss the advantages and limitations of each procedure, specific pitfalls when interpreting images, and the most important results from the literature, and also provide recommendations on the appropriate use of multimodality imaging.

BACKGROUND: Aim of the study was to evaluate the diagnostic performance of FDG PET-CT for the detection of local and distant disease relapse in surgically treated patients with renal cell carcinoma (RCC). MATERIAL AND METHODS: This retrospective study includes 96 patients underwent FDG PET-CT scanning in the post-surgical follow up within the first 6–12 months referred to nuclear medicine department, to perform PET/CT study. Each patient underwent FDG PET-CT with low dose CT, followed immediately by full dose Ce-CT. Sites of the relapse were categorized into local and distant recurrence. Distant recurrence sites were divided into lymph nodes, lung, bone, and other soft tissue sites. The final diagnosis of disease status was made on subsequent follow up by conventional imaging (CT/MRI), FDG PET-CT, or histopathology whenever possible. RESULTS: Local and/or distant disease relapse was confirmed in 69 (71.9%) patients and the rest 28.1% were free. Regarding local recurrence FDG PET-CT showed specificity of 100% compared to 98.6% with Ce-CT (p > 0.05) and higher sensitivity noted with Ce-CT (100%) compared to 96% with FDG PET-CT. For global distant sites of metastases Ce-CT revealed high sensitivity and NPV of 93.3% & 96.9% respectively yet lower specificity (93.96%) and PPV (87.5%) was seen with Ce-CT compared to 99.6% and 99.1% with FDG PET-CT respectively. The higher Ce-CT sensitivity was attributed to its ability to detected 100% of cases of lung metastases compared to 80.6% with FDG PET-CT (P-value < 0.05). CONCLUSION: FDG PET-CT appears to be a very efficient tool in post-surgical surveillance of patients with RCC with notable ability to probe even uncommon sites of distant recurrence.

A 72-year-old male patient with a history of polycystic kidney disease and lung malignancy underwent F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) for the evaluation of tumor recurrence. The FDG PET/CT and subsequent non-enhanced CT scans revealed a hemorrhage in the peri-renal space of the left original kidney. Interesting in this case was the incidental detection of unexpected peri-renal hemorrhage during an oncologic assessment with FDG PET/CT.

The incidence of malignant adrenal tumors, including primary adrenal lymphoma (PAL) and adrenocortical carcinoma (ACC), is rather low. Early differentiation between ACC and PAL is necessary because the therapeutic strategies for the two differ and the prognosis of each disease is poor. Unfortunately, there is no pathognomonic characteristic of PAL, so radiologists have difficulty in differentiating it from ACC. To our knowledge, there have been only two case reports on ACC that was evaluated and followed up using F-18 FDG PET/CT. The previously reported cases were simple, involving only the bilateral adrenal glands. Here, we report on a 52-year-old man diagnosed with PAL that radiologically mimicked ACC. He had findings of heterogeneous enhancement on CT, several adjacent lymphadenopathies with internal necrosis, and abutting hepatic and bilateral crural invasion. After pathological confirmation, we monitored his prognosis using F-18 FDG PET/CT after three cycles of rituximab-CHOP and again after six cycles of treatment.

The purpose of this study was to assess the occupational radiation exposure arising from positron emission tomography combined with X-ray computed tomography (PET/CT) procedures. From 2009 through the end of 2014, in a team of six technologists, personal dosimetry was performed using electronic personal dosemeters and film badge dosemeters. The technologists registered the separate exposure after each PET/CT operational step, which included radiopharmaceutical arrival, dispensing in individual syringes, injection and patient positioning.From the total of 3024 PET/CT procedures, 2142 were available for analysis. The personal dose equivalent for the technologists performing PET/CT ranged from 11.5 nSv/MBq to 23.8 nSv/MBq. Whole-body radiation dose originated mainly from radiopharmaceutical injection (41.5%) and patient positioning (51.1%). The sources of occupational exposure were successfully identified for PET/CT procedures. Record keeping using on-site occupational dosimetry is a useful tool for exposure optimisation.

Background The aim of this study was to (1) evaluate the ability of F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) parameters to predict suboptimal cytoreduction and (2) to create a risk model for predicting suboptimal cytoreduction in advanced ovarian cancer. From 2011 to 2015, 51 patients underwent primary cytoreductive surgery for advanced ovarian cancer were enrolled. A residual disease with maximal diameter > 1 cm was considered a suboptimal surgical result. The SUVmax values for nine abdominal regions, the sum of 9 regional SUVmax (WB1SUVmax) and WB2SUVmax (WB1SUVmax plus SUVmax of lymph nodes) were used for PET parameter. Multiple logistic regression analysis was used to determine the predictive value of PET and clinical parameters for risk model. In addition, assessments of disease-free survival (DFS) and overall survival (OS) were performed. Results Seventeen of the 51 patients (33.3%) underwent suboptimal cytoreduction. The ECOG status (OR, 4.091), SUVmax of central (OR, 5.250), right upper (OR, 4.148), left upper (OR, 5.921) and WB2SUVmax (OR, 4.148) were associated with suboptimal cytoreduction. The risk model can divide the risk groups of suboptimal cytoreduction (area under the curve (AUC), 0.775; p = 0.0001). The DFS and OS in the high-risk group were significantly worse than those in the low-risk group (p = 0.0379 for DFS; p = 0.0211 for OS). Conclusions The presence of hypermetabolic lesions in the central, right upper, and left upper regions showed predictive value for suboptimal cytoreduction. Our risk model may be helpful for selecting patients who may show suboptimal cytoreduction.

We evaluated the prognostic significance of the combined use of F-18 FDG (FDG) and F-18 FLT (FLT) PET/CT (PET/CT) in patients (pts) with multiple myeloma (MM) suspected relapse after a first line chemotherapy.twenty-eight patients (57 ± 12 years) underwent both PET/CT scans over 2-4 weeks. Patients were grouped according to imaging results (FDG+/-; FLT+/-) and the findings compared to the event free survival (EFS).five pts had FDG+; FLT+, 8 showed FDG+;FLT-, two had FDG-;FLT + and 13 presented FDG-;FLT-, mostly (87 %) of FDG+;FLT- pts had destructive lytic bone lesions. At Cox regression analysis the FDG PET/CT (HR 4.4, 95 % CI 1.3-15.4, p0.05) and FLT PET/CT (HR 5.8, 95 % CI 1.7-19.3, p0.01) were predictive of worst prognosis. The Kaplan-Meier analysis showed that FDG and FLT PET/CT independently influenced the survival. FDG-;FLT-patients had better EFS as compared to FDG+; FLT + pts and FDG-;FLT + pts, those of FDG+;FLT- group also had worsened EFS.results from the aggregate use of PET/CT FDG and FLT in MM represent a valuable prognostic indicator for identifying patients at higher risk of undue events and may help to correctly stratify the patients with suspected relapse.