Value Of PET-CT Research Articles

Comparing the Diagnostic Value of FDG PET or PET/CT With FDG PET/MR in Inflammatory Bowel Disease-A Systematic Review and Meta-analysis.

The aim of this study was to compare the diagnostic value of 18 F-FDG PET or PET/CT with FDG PET/MR in patients with inflammatory bowel disease (IBD). A comprehensive search was performed in PubMed for studies reporting the diagnostic performance of FDG PET (PET/CT) and FDG PET/MR in IBD from the inception of the database to March 14, 2024, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Fourteen studies were included in this systematic review and meta-analysis. Pooled estimates of segment-based sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for FDG PET (PET/CT) and FDG PET/MR were calculated alongside 95% confidence intervals. Summary receiver operating characteristic (SROC) curves were plotted, and the area under the SROC curve was determined alongside the Q * index. The segment-based pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the SROC curve of FDG PET (PET/CT) for diagnosing IBD (9 studies) were 0.81, 0.86, 5.76, 0.22, 31.92, and 0.92, respectively. Those of FDG PET/MR (5 studies) were 0.78, 0.92, 10.97, 0.25, 51.79, and 0.95. There was no significant difference in the abilities of detecting or excluding IBD between FDG PET (PET/CT) and FDG PET/MR. For diagnostic value in patients with IBD, there was no significant difference between FDG PET (PET/CT) and FDG PET/MR. Both FDG PET (PET/CT) and FDG PET/MR have demonstrated high diagnostic performance for accurate diagnosing in patients with IBD.

Progress in treatment of primary mediastinal large B-cell lymphoma

Primary mediastinal large B-cell lymphoma (PMBCL) is an aggressive B-cell lymphoma originating from the thymus, which has different clinical and biological characteristics from diffuse large B-cell lymphoma, NOS. PMBCL tends to occur in young women, usually presenting as a large anterior mediastinal mass. Most patients are in stage Ⅰ-Ⅱ at the time of presentation. There is no standard prognostic scoring system for PMBCL. Immunochemotherapy is commonly used in the treatment of PMBCL, but the optimal first-line treatment has not been determined, and the status of radiotherapy is controversial. The value of PET-CT guided therapy needs to be further verified. Relapsed/refractory PMBCL has a poor prognosis, while novel therapies such as PD-1 inhibitors, brentuximab vedotin, and CAR-T can help improve survival in these patients.

The Effect of Hounsfield Unit Value on the Differentiation of Malignant/Benign Mediastinal Lymphadenopathy and Masses Diagnosed by Endobronchial Ultrasonography.

In cases where standardized maximum uptake (SUVmax) values in positron emission tomography (PET-CT) were not sufficient to differentiate mediastinal lymphadenopathy and masses from malignant or benign, the contribution of Hounsfield unit (HU) values in thorax computed tomography to the diagnosis was evaluated. The study was conducted by evaluating the data of 182 patients between 2019 and 2023. HU values on non-contrast thorax computed tomography and PET-CT SUVmax values of biopsied masses and lymph nodes were compared with histopathological diagnoses. Patients, 58 females (31.9%) and 124 males (68.1%), who underwent EBUS were included in the study. Biopsies were taken from 233 stations (199 lymph nodes, 34 masses) from 182 patients. A total of 135 of the biopsies taken from 233 stations were histopathologically malignant and 98 were benign. While PET-CT SUVmax values of cases with benign histopathology were 4.5 ± 3.5, it was 7.6 ± 4.2 in patients with malignant pathology (p<0.05). The HU value on non-contrast thorax tomography in patients with benign histopathology was 43.1 ± 15.7, and in patients with malignant histopathology it was 40.5 ± 13.7 (p>0.05). When HU was compared according to lung cancer type, it was found to be significantly higher in non-small cell lung cancer (p=0.035). A weak (r=0.182) positive and significant relationship (p<0.01) was found between PET-CT values and HU values in thorax computed tomography. While positron emission tomography maintains its importance in the differentiation of mediastinal lymphadenopathy and masses from malignant to non-malignant, it was concluded that HU values in computed tomography are not sufficient to distinguish malignant/non-malignant.

Positive Predictive Value of PET CT in HPV Associated Oropharyngeal Cancers Treated with Definitive Proton Therapy

Proton therapy (PT) offers attractive dosimetric advantages but there is emerging literature suggesting relative biological effectiveness (RBE) differences at the distal end of the Bragg peak may result in increased posttreatment FDG avidity. While the utility of PET CT is well established, lingering posttreatment inflammation from PT may affect the interpretation of posttreatment scans (PTS). We seek to characterize the positive predictive value (PPV) and negative predictive value (NPV) for residual disease/locoregional recurrence in patients undergoing definitive PT with HPV associated oropharyngeal cancer. We performed a single institution retrospective analysis of patients with HPV associated oropharyngeal cancer treated with PT between 2016-2022. Patients were included if they had both pretreatment and initial posttreatment restaging PET/CT available for analysis. SUVmax was recorded in both the primary tumor and involved lymph nodes. Patients were considered to have a positive PET CT if there was an SUV decrease of less than 65% from the baseline exam or if there was SUV > 4.0 based on thresholds defined by previous studies. Chi-square analysis was used to compare patients who had a positive PTS to those who did not. Sixty-two patients were included for analysis with a median age of 62. The entire cohort had a median follow up of 21 months (Range 2-71 months) of whom 86% received chemotherapy. Eleven patients (17%) had PTS defined as positive, of whom only one (PPV 9%) was found to have residual/locoregionally recurrent disease within an area of FDG avidity on PTS. Another patient developed a new primary tumor 9 months later in an area outside of FDG avidity on PTS. The remainder were followed with serial clinical exam with or without the compliment of repeat imaging. They remained without evidence of residual/locoregionally recurrent disease at the time of last follow up. Fifty-one patients had negative posttreatment scans, with only one patient having residual/locoregionally recurrent disease (NPV 98%). On Chi-square analysis T1-2 vs T3-4 tumor, use of CTV margin vs no margin, chemotherapy vs no chemotherapy, smoking history, and tonsil vs base of tongue subsite were not statistically significant in association with positive PTS. PET/CT for post-treatment evaluation of patients treated with PT had an expectedly high NPV of 98% for residual/locoregionally recurrent disease; however, the PPV was 9% (1/11) which is much lower than would be expected with photon-based treatment. These findings may be the result of lingering acute inflammation caused by RBE differences at the distal end of the Bragg peak. Our findings are hypothesis generating and require validation with larger well-matched patient cohorts.

The Clinical Value of PET-CT in Searching for Primary Lesions of Malignances

This paper is aimed to explore the clinical value of 18F-FDG PET-CT in searching for primary lesions of multiple metastatic malignances. Data of 35 patients with multiple metastatic malignances which the primary lesion was not clear, were retrospectively studied from January 2019 to April 2023 in our hospital. Systemic 18F-FDG PET-CT examination was performed for all the patients, and the follow-up data were analyzed and summarized. The positive rate of 18F-FDG PET-CT for primary malignant lesions was 74.29% (26/35), the specificity was 87.28%, the sensitivity was 85.43%, and the accuracy was 88.73%. The positive predictive value was 92.31% (24/26). 18F-FDG PET-CT showed a high detection rate of metastatic squamous cell carcinoma and metastatic adenocarcinoma, with 85.36% and 82.41% respectively. 18F-FDG PET-CT examination provides high clinical value in multiple searches of primary metastasis throughout the body.

MAOA suppresses the growth of gastric cancer by interacting with NDRG1 and regulating the Warburg effect through the PI3K/AKT/mTOR pathway.

Previous studies have indicated that neurotransmitters play important roles in the occurrence and development of gastric cancer. MAOA is an important catecholamine neurotransmitter-degrading enzyme involved in the degradation of norepinephrine, epinephrine and serotonin. To find a potential therapeutic target for the treatment of gastric cancer, the biological functions of MAOA and the underlying mechanism in gastric cancer need to be explored. The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO) datasets, Kaplan‒Meier (KM) plotter were used to identify the differentially expressed genes, which mainly involved the degradation and synthesis enzymes of neurotransmitters in gastric cancer. We also investigated the expression pattern of MAOA in human and mouse tissues and cell lines by immunohistochemistry and Western blotting analysis. Western blotting, quantitative real-time PCR, enzyme-linked immunosorbent assay (ELISA) and a Seahorse experiment were used to identify the molecular mechanism of cancer cell glycolysis. MAOA expression and patient survival were analysed in the Ren Ji cohort, and univariate and multivariate analyses were performed based on the clinicopathological characteristics of the above samples. MAOA expression was significantly downregulated in gastric cancer tissue and associated with poor patient prognosis. Moreover, the expression level of MAOA in gastric cancer tissue had a close negative correlation with the SUXmax value of PET-CT in patients. MAOA suppressed tumour growth and glycolysis and promoted cancer cell apoptosis. We also reported that MAOA can interact with NDRG1 and regulate glycolysis through suppression of the PI3K/Akt/mTOR pathway. MAOA expression may serve as an independent prognostic factor in gastric cancer patients. MAOA attenuated glycolysis and inhibited the progression of gastric cancer through the PI3K/Akt/mTOR pathway. Loss of function or downregulation of MAOA can facilitate gastric cancer progression. Overexpression of MAOA and inhibition of the PI3K/Akt/mTOR pathway may provide a potential method for gastric cancer treatment in clinical therapeutic regimens.

Diagnosis value of 18F-Fluoro-d-glucose positron emission tomography-computed tomography in pulmonary hamartoma: a retrospective study and systematic review

PurposeThe diagnosis of pulmonary hamartoma (PH) based on computed tomography (CT) is a challenge, especially in patients with atypical imaging characteristics. This study was aimed at summarizing the imaging characteristic of 18F-Fluoro-d-glucose positron emission tomography-computed tomography (18F-FDG PET-CT) in PH and exploring the application value of PET-CT in the diagnosis of PH.Data and methodsPatients diagnosed with PH who had undergone PET-CT from literature pertaining were retrospectively analyzed, which were cases of publications from the Cochrane Library, PubMed, Excerpta Medica Database (EMBASE), China National Knowledge Infrastructure (CNKI) and Wanfang databases, from 2008 to June 2022. The other 20 cases of the collection were patients from our hospital from 2008 to June 2022. Patients’ symptoms, imaging characteristics of chest CT, PET-CT characteristics, the reason for PET-CT and the complications were analyzed.ResultsIn this retrospective study, a total of 216 patients were diagnosed with PH and had been examined by PET-CT. 20 of the cases were patients of our hospital from January 2008 to June 2022. The other cases were collected from the literature. The mean diameter of most PH lesions is 1.7 ± 1.0 cm. The mean maximum standardized uptake value (SUVmax) of the PH lesions was 1.2 ± 1.1. Most of their SUVmax were lower than internationally recognized cut-off value (SUVmax = 2.5). PET-CT was superior to CT in the diagnosis of PH but there was a correlation of between CT diagnosis and PET-CT diagnosis for the PH lesions. In order to draw the Receiver operating characteristic (ROC), we selected 29 patients with a clear SUVmax value of their PH lesion, and 29 lung cancer patients with clear SUVmax value in our hospital were collected as a control group. ROC curve analysis showed that the area under curve (AUC) of SUVmax was 0.899, and the optimal diagnostic threshold was SUVmax > 2.65. PET-CT could distinguish PH from malignant lesions with a sensitivity of 89.66% by applying a SUVmax of 2.65 as a cut-off in this study.ConclusionPET-CT might be a useful tool to diagnose PH, which shows a better diagnostic sensitivity than CT. But PET-CT can not be used as a single diagnostic approach, which should be combined with other methods and the patients’ history to make the most correct diagnosis.

PET/CT Prediction of Head and Neck Melanoma Nodal Metastases

<h3>Purpose/Objective(s)</h3> Lymph node dissection is an important oncologic treatment for many head and neck melanomas. Over time, surgeons have narrowed the basins covered by neck dissections based on the underlying disease. In melanoma, there is a need for diagnostic modalities that can effectively predict locoregional metastasis to tailor the extent of neck dissection. PET-CT is an imaging modality often employed in oncologic staging, but definitive data are lacking on basin-specific predictive capabilities of PET-CT for head and neck melanoma. The objective of this study is to determine the predictive value of PET-CT for detecting melanoma metastasis to head and neck lymph node basins. <h3>Materials/Methods</h3> This is a retrospective case series of adults who underwent lymphadenectomy for melanoma metastasis to the neck at a single tertiary academic medical center from 2000-2018. Exclusion criteria included: prior head and neck radiation or lymphadenectomy except for sentinel lymph node biopsies, lack of preoperative PET-CT images, incomplete pathology records, or less than one year of follow-up. Demographic data, clinical and pathologic staging, surgical details, and post-operative complications were collected. The eighth edition of the American Joint Committee on Cancer staging system was used. PET-CT was performed according to institutional protocol, and all PET-CT images were re-reviewed by a board-certified nuclear medicine physician blinded to pathology results. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of PET-CT for predicting nodal metastasis were calculated by comparing the results of the PET-CT to final pathology, which was considered the gold standard for this study. <h3>Results</h3> 108 subjects were included, 2 of whom had bilateral neck dissections, for a total of 110 neck dissections. Median follow-up was 2.0 years. The average age (SD) was 63 (14), 74% were male, and 93% identified as Caucasian. The most common primary sites were the face (n=30), scalp (n=29), and neck (n=23). The majority of tumors were classified as T2-T4 (77%) and as either cN1 (n=55) or cN0 (n=26) disease. The most frequent surgical complications included seroma (n=7) and hematoma (n=5). There were no reports of gross nerve injury or permanent neuropathies. When compared to final pathology, preoperative PET-CT had a 90% sensitivity (CI 79.5%-95.6%), 92% specificity (CI 80.7 %-97.4%), 93.1% PPV (CI 83.1%-97.8%), and 88.5% NPV (CI 76.7%-95%). In 86.5% of neck dissections, there was concordance on nodal basin metastases between PET-CT and final surgical pathology. <h3>Conclusion</h3> PET-CT demonstrates acceptable predictability of locoregional head and neck melanoma metastases with nodal basin concordance. This information could be incorporated into shared decision making regarding the extent of regional lymph node dissection as treatment paradigms shift.

Interim and end-of-treatment PET-CT suffers from high false-positive rates in DLBCL: Biopsy is needed prior to treatment decisions.

The application of positron emission tomography (PET)‐computed tomography (CT) in treatment response evaluation has increased in diffuse large B‐cell lymphoma (DLBCL), although its predictive value is controversial. We retrospectively analyzed the rate of false‐positive PET‐CTs performed as interim (n = 94) and end‐of‐treatment (n = 8) assessments among 102 DLBCL patients treated during 2010–2017 at Oulu University Hospital. In PET‐CT Deauville score ≥4 was regarded as positive. A biopsy was performed on 35 patients, and vital lymphoma tissue was detected from nine patients. Positive biopsy findings were associated with poor disease outcomes in this study. This difference was statistically significant: 2‐year failure‐free survival (FFS) was 44% in patients with a positive biopsy versus 83% for those with a negative biopsy (p = 0.003). The corresponding overall survival (OS) rates were 53% versus 95% (p = 0.010). In the multivariate analyses, a negative biopsy was an independent protective factor in FFS (Hazard Ratio (HR) 0.093 (95% confidence interval [CI] 0.017–0.511); p = 0.006) unrelated to the International Prognostic Index (IPI) (HR 1.139 [95% CI 0.237–5.474] p = 0.871) or stage (HR 1.365 [95% CI 0.138–13.470]; p = 0.790). There was no statistically significant difference in OS according to the PET results, but the FFS rate was significantly higher in patients with a negative PET. The value of PET‐CT as an evaluation method suffers from a high false‐positive rate, and it is inadequate alone for the justification of treatment decisions. Biopsy results provide more reliable prognostic information for the evaluation of treatment response and outcome and should be used to assess patients with positive PET‐CT scans.

Norepinephrine Enhances Aerobic Glycolysis and May Act as a Predictive Factor for Immunotherapy in Gastric Cancer.

Methods Monoamine neurotransmitters were detected in gastric cancer tissue and paired normal tissue, and The Cancer Genome Atlas was used to identify differentially expressed norepinephrine-degrading and synthetic enzymes. Quantitative real-time PCR and the Seahorse assay were used to determine the effect of norepinephrine on gastric cancer cell glycolysis. MAOA expression in cancer tissues was analyzed by immunohistochemistry and was compared with the patient SUVmax value of PET-CT and other clinicopathological characteristics. Results The norepinephrine levels were markedly high in gastric cancer tissue, while the norepinephrine-degrading enzymes MAOA and MAOB showed low expression. High norepinephrine levels were associated with activated glycolysis. The MAOA or MAOB expression levels in tumor tissue were closely correlated with the patient SUV max values of PET-CT and immunotherapy evaluation indices, such as PD-L1 and the microsatellite status. Conclusions Norepinephrine shows relatively higher expression in gastric cancer tissue than in normal tissue, and its expression level is associated with the glycolysis levels in patients. The norepinephrine-degrading enzymes MAOA and MAOB have significant expression differences in cancer and normal tissue, and their missing or low expression may predict immune therapy outcomes for gastric cancer patients. High norepinephrine levels with metabolic abnormalities may be more suitable for metabolic targeted therapy or immunotherapy.

Impact of Pre-operative Positron Emission Tomography - Computed Tomography for Management of Gallbladder Cancer

Background: Prognosis of gallbladder carcinoma is poor; surgery with R0 resection remains the only chance for long-term survival for these patients.Extensive evaluation is mandatory to accurately define the tumor stage,regional lymph nodes and distant metastases to identify those patients who may benefit from surgery.The purpose of this study was to assess the diagnostic value of PET-CT in relation to a conventional imaging modality,CECT for patients with gallbladder cancer. Methods: This study was prospective observational study conducted at tertiary care institute.Seventy patients with suspected gallbladder cancer who underwent both PET-CT and MDCT for initial staging were included in our study.Results of these two imaging modalities for evaluating primary tumors, regional lymph nodes and distant metastases were compared with the final diagnoses based on histopathological examination. Results: PET-CT demonstrated no significant advantage over MDCT for the diagnosis of a primary tumor.PET-CT showed a significantly higher accuracy (90.8vs.80.0%,P=0.04) than MDCT for diagnosis of regional lymph node metastasis. PET-CT showed significantly higher sensitivity (92.3vs.61.5%,P=0.04) than MDCT in the diagnosis of distant metastasis.Addition of PET-CT changed management in 10 patients(14.3%).In seven patients,radical resection was avoided due to presence of distant lymph nodal disease or distant metastases diagnosed on PET-CT.In three patients with suspicious CT finding,PET was negative for malignancy. Conclusions: In patients with potentially recectable gallbladder carcinoma on primary imaging, PET-CT may be helpful in detecting distant nodal metastasis and unsuspected metastatic disease that may preclude patients from surgical resection.Addition of preoperative PET-CT in staging of gallbladder carcinoma, also result in change of management in significant number of patient.

Diagnostic Laparoscopy Improves Staging of Malignant Pleural Mesothelioma With Routine Positron Emission Tomography Imaging

With a multimodal treatment strategy, cytoreductive surgery extends survival in malignant pleural mesothelioma. Improving the accuracy of staging can refine patient selection. Our objective was to determine whether diagnostic laparoscopy (DL) improves staging for patients with malignant pleural mesothelioma with the routine use of positron emission tomography (PET). We performed a retrospective review of our prospectively maintained database from February 2014 to May 2019. Inclusion criteria were patients who had disease in the chest that was deemed potentially resectable by radiographic criteria and who underwent DL as part of the staging evaluation before surgery. Of 187 patients (71% men, 80% epithelial) who underwent DL during staging, 76% proceeded to surgery; 22% were unresectable at exploratory thoracotomy and 78% underwent resection (pleurectomy and decortication, 68%; extrapleural pneumonectomy, 32%). Also, 89% had a PET computed tomography (CT), and 11% had a preoperative CT without PET. DL revealed peritoneal disease in 17%. Among patients with pathologically proven disease at DL, 77% had negative PET-CT imaging. Based on the pathologic findings at DL the sensitivity, specificity, positive predictive value, and negative predictive value of PET-CT were 23%, 78%, 17%, and 83%, respectively. The accuracy of PET-CT was 68%. PET-CT has low sensitivity and diagnostic accuracy to identify peritoneal disease in malignant pleural mesothelioma. DL as part of the preoperative staging defines an important subset of patients with bicavitary disease. We recommend DL as a component of staging before surgery.

Sequential 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) scan findings in patients with extrapulmonary tuberculosis during the course of treatment—a prospective observational study

Initial studies of tuberculosis (TB) in macaques and humans using 18F-FDG positron emission tomography (PET) imaging as a research tool suggest its usefulness in localising disease sites and as a clinical biomarker. Sequential serial scans in patients with extrapulmonary TB (EPTB) could inform on the value of PET-CT for monitoring response to treatment and defining cure. HIV-negative adults with EPTB from eight sites across six countries had three 18F-FDG PET/CT scans: (i) within 2weeks of enrolment, (ii) at 2months into TB treatment and (iii) at end of ATT treatment. Scanning was performed according to the EANM guidelines. 18F-FDG PET/CT scans were performed 60 ± 10min after intravenous injection of 2.5-5.0MBq/kg of 18F-FDG. One hundred and forty-seven patients with EPTB underwent 3 sequential scans. A progressive reduction over time of both the number of active sites and the uptake level (SUVmax) at these sites was seen. At the end of WHO recommended treatment, 53/147 (36.0%) patients had negative PET/CT scans, and 94/147 (63.9%) patients remained PET/CT positive, of which 12 patients had developed MDR TB. One died of brain tuberculoma. Current 18F-FDG PET/CT imaging technology cannot be used clinically as a biomarker of treatment response, cure or for decision-making on when to stop EPTB treatment. PET/CT remains a research tool for TB and further development of PET/CT is required using new Mycobacterium tuberculosis-specific radiopharmaceuticals targeting high-density surface epitopes, gene targets or metabolic pathways.

The role of FDG-PET-CT is limited in initial staging of nodal metastasis for thin cutaneous melanoma

IntroductionPositron emission tomography computed tomography (PET-CT) is often used to stage nodal metastases in thin cutaneous melanoma, with limited evidence. MethodsA retrospective review of patients with cutaneous malignant melanoma treated at our institution was performed from 2005 to 2015, identifying those who received a PET-CT prior to lymphadenectomy. Biopsy features, lymph node status, and PET-CT results were collected. We calculated the overall sensitivity, specificity, accuracy, likelihood ratios, and positive predictive value of PET-CT in identifying nodal metastases. Results were stratified by initial biopsy tumor depth. ResultsWe identified 367 cases; 95 obtained a PET-CT prior to lymphadenectomy. Overall, sensitivity and specificity of PET-CT was 34.6% and 95.4%, respectively. The positive likelihood ratio and negative likelihood ratio were 7.62 and 0.68, respectively. The accuracy was 78.2%. The positive predictive value for T3 and T4 melanomas were 100% and 81.4%, respectively. For thin melanomas, specificity and accuracy was 88.2% and 88.2%, respectively. ConclusionsPET-CT has low specificity and its use alone is not recommended for initial staging of nodal metastases in thin cutaneous malignant melanoma.

The Value of PET-CT in Ovarian Epithelial Carcinoma: A Population-Based Study in British Columbia, Canada

IntroductionIn epithelial ovarian cancer (EOC), consensus regarding optimal use of PET/CT is lacking. Limited evidence suggests its accuracy in preoperative staging, investigating recurrence and predicting optimal secondary debulking. This study evaluated indications for PET/CT, impact of PET/CT results on EOC management, and its added value over conventional imaging. MethodsPatients with EOC aged 19 years and older who underwent PET/CT at BC Cancer Vancouver between January 2007 and September 2017 were eligible. Medical records were retrospectively reviewed with the following data abstracted: patient demographics, PET/CT indications and results, recent conventional imaging results, and application of PET/CT findings. Basic descriptive analysis was performed to determine most common use of PET/CT and its management impact. Results257 PET/CTs in 216 patients were eligible. Most PET/CTs (135/257, 52.6%) were performed for suspected disease recurrence/progression. Management after PET/CT changed in 1/3 of cases with the greatest impact seen when assessing suitability in recurrent disease for focal radiotherapy or secondary surgical debulking. For 106/257 cases with recent conventional imaging available, although differences in disease extent were found in ~50%, clinical conclusions drawn were the same in ~75%. DiscussionAlthough PET/CT is most commonly used to investigate suspected recurrence/progression, its impact on management here is low. Greater impact is seen when considering localized therapy in EOC recurrence. When compared with recent conventional imaging, although PET/CT may detect differences in disease extent, clinical conclusions are frequently the same. ConclusionImpact of PET/CT on management is greatest in EOC recurrence when considering local therapies, beyond which clinical presentation and conventional imaging may suffice.

Predictive Value of PET-CT in Patients with T-Cell Lymphoma Undergoing Autologous and Allogeneic Stem Cell Transplant

Introduction T-NHL are associated with an aggressive clinical course and poor outcomes. The role of PET-CT at the time of SCT (pre-SCT), BM biopsy, and peripheral blood (PB) flow cytometry have not been well investigated. We retrospectively analyzed 83 pts with T-NHL undergoing auto or allo SCT to determine the predictive value of pre-SCT PET-CT scan, BM and PB flow for relapse-free survival (RFS) and OS. Methods PET CR was defined as the absence of any radiographic dz by PET-CT (5-pt score). Overall CR was defined as negative PET, BM and PB flow. Pre-SCT variables were assessed for their effects on RFS and OS: age, number of previous lines of therapy, CIBMTR dz risk, pre-SCT BM, pre-SCT PB flow, and pre-SCT PET-CT. Results Of 83 pts studied, 49 were autoSCT and 34 were alloSCT. Six pts who underwent alloSCT had received a prior autoSCT. Diagnosis was PTCL NOS 34, AITL 23, CTCL/Sezary syndrome 11, nasal NK-T 6, EATL 3, SPTCL 2, hepatosplenic 1, ALK-ALCL 1, HTLV-2 ATL 1, T-lymphoblastic 1. The majority of pts with AITL (16/23) underwent autoSCT upfront. Conditioning for autoSCT was BEAM. Conditioning for alloSCT was Pentostatin/TBI in all but 6 SCT. Median lines of therapy prior to SCT were 1 for auto and 4 (r 2-13) for alloSCT. Median age at SCT was 60 (r 20-75). A total of 6 out of 49 (12%) autoSCT and 8 out of 34 (24%) alloSCT had positive PET-CT (score 4-5) at the time of SCT. BM was positive in 8 out of 49 (16%) at the time of autoSCT and 7 out of 34 (21%) at the time of alloSCT. PB flow was positive in 9 out of 49 (18%) at the time of auto SCT and 6 out of 34 (12%) at the time of alloSCT. CIBMTR dz index was low in 57(69%), intermediate in 15(18%), and high in 11 (13%) of 83 SCT. The majority of allo-SCT were intermediate-high risk. The median follow-up 56 months (r 6 - 122). Twenty (24%) pts had expired. Univariate analysis of pre-autoSCT variables did not reveal statistically significant (SS) results for BM or PET positivity. Univariate analysis of pre-alloSCT variables identified positive BM and positive PET/CT scan as being SS. There was a SS lower incidence of relapse, longer RFS and OS in alloSCT pts with either negative pre-SCT PET-CT scan or negative pre-SCT BM. Other pre-SCT variables tested were not SS. In multivariate analysis, pre-alloSCT PET-CT alone retained SS. Pre-alloSCT PET-CT scan was a strong predictor of 2-yr RFS and 2-yr OS. Conclusion This data indicates that in heavily pretreated pts with T- NHL undergoing alloSCT, a negative pre-SCT PET-CT is a statistically significant predictor of long-term RFS and OS regardless of dz risk and number of lines of therapy. Due to the small number of autoSCT with positive PET-CT scans, BM biopsy, or PB flow at the time of SCT, no association between the above-mentioned variables and relapse was identified. Further studies with larger numbers of pts are warranted to determine the role of pre-autoSCT PET-CT, BM and PB flow as prognostic factors in T-NHL.

18F-Fluorodeoxyglucose Positron Emission Tomography Computed Tomography (PET/CT) for the diagnosis of prosthetic valve infective endocarditis (PVIE): A prospective multicenter study

18 F-FDG PET/CT has been added as a major criterion in the ESC 2015 infective endocarditis (IE) guidelines, but the value of this new diagnostic algorithm has never been prospectively assessed. To assess the value of the new ESC criteria including PET/CT in prosthetic valve infective endocarditis (PVIE). Secondary objectives: to determine the reproducibility of PET/CT and to assess its ability to predict embolic events. Between 2014 and 2017, 175 patients with suspected PVIE were prospectively included in 3 French centers. After exclusion of patients with uninterpretable or not feasible PET/CT, 115 patients were finally included, including 91 definite IE and 24 rejected IE, as defined by a Consensus of Endocarditis Team after 3-month follow-up as Gold Standard. Nuclear data were blindly analyzed by two independent nuclear medicine physicians. Significant cardiac uptake by PET/CT was observed in 67 among 91 patients with definite PVIE and 6 patients with rejected IE (sensitivity 73.6%, specificity 75%, positive predictive value 91%, negative predictive value 42%). Considering cardiac uptake as a major criterion, the ESC 2015 classification increased the sensitivity of Duke criteria from 57 to 84% ( P < 0.001) but decreased its specificity from 84 to 70% ( P < 0.001). Intraobserver reproducibility of cardiac uptake evaluation was good (kappa = 0.84) but inter observer reproductibility was less satisfactory ( k = 0.63). Embolic events occurred in 31 patients (27%) and were correlated with PET/CT cardiac uptake ( P = 0.02) among others. The value of PET CT and ESC criteria is confirmed and may allow earlier diagnosis of PVIE. Reproducibility of nuclear measurements seems unsatisfactory, justifying efforts to standardize PET studies interpretation. Our study describes for the first time a positive correlation between a positive PET/Ct and occurrence of embolic events, warranting additional studies.

The Role of Staging PETCT Pt4b Melanoma: A 5 Year Analysis

Aim: In our Trust, patients diagnosed with pT4b cutaneous melanoma are offered PETCT for initial staging as a sensitive way to detect tumour metastasis. We assessed the value of PETCT in these patients in terms of positive findings from the scan and subsequent recurrence and survival.

333018F-Fluorodeoxyglucose Positron Emission Tomography Computed Tomography (PET/CT) for the diagnosis of prosthetic valve infective endocarditis (PVIE): a prospective multicenter study

Abstract Background and objectives 18F-FDG PET/CT has recently been added as a major criterion in the ESC 2015 infective endocarditis (IE) guidelines, but the value of this new diagnostic algorithm has never been prospectively assessed. Purposes 1. Primary objective: to assess the value of the new ESC criteria including 18F-FDG PET/CT in prosthetic valve infective endocarditis (PVIE). 2. Secondary objectives: to determine the reproducibility of 18F-FDG PET/CT; to assess its ability to predict embolic events. Methods Between 2014 and 2017, 175 patients with suspected PVIE were prospectively included in 3 French centers. After exclusion of patients with uninterpretable or not feasible PET/CT,115 patients were finally included in the analysis, including 91 definite IE and 24 rejected IE, as defined by an expert Consensus of Endocarditis Team after 3-month follow-up as Gold Standard Nuclear data were blindly analyzed by two independent nuclear medicine physicians. Patients follow-up was scheduled at one and three months after hospitalization Results Significant cardiac uptake by PET/CT (major criterion) was observed in 67 among 91 patients with definite PVIE and 6 patients with rejected IE (sensitivity 73.6%, specificity 75%, positive predictive value 91%, negative predictive value 42%). Considering cardiac uptake as a major criterion, the ESC 2015 classification increased the sensitivity of Duke criteria from 57 to 84% (p&lt;0.001) but decreased its specificity from 84 to 70% (p&lt;0.001). Intraobserver reproducibility of cardiac uptake evaluation was good (kappa = 0.84) but inter observer reproductibility was less satisfactory (kappa = 0.63). Embolic events occurred in 31 patients (27%) and were correlated with vegetation size by ECHO (p&lt;0.001), Staphylococcus infection (p=0.003), and PET/CT cardiac uptake (p=0.02). Conclusion 1. the value of PET CT and ESC criteria is confirmed and may allow earlier diagnosis of PVIE 2. PET CT is associated with an increased risk of false positive results probably related to the technical improvements 3. Reproducibility of nuclear measurements seems unsatisfactory, justifying efforts to standardize PET studies interpretation 4. Our study describes for the first time a positive correlation between a positive PET/Ct and occurrence of embolic events, warranting additional studies.

Choosing the right preoperative imaging: Prognostic value of PET-CT compared to CT for preoperative planning in high risk histology endometrial carcinoma

Choosing the right preoperative imaging: Prognostic value of PET-CT compared to CT for preoperative planning in high risk histology endometrial carcinoma