Comparison of MRI, PET, and 18F-choline PET/MRI in patients with oligometastatic recurrent prostate cancer

Objectives The aims of the study were (i) to examine the PCa detection rate of 18F-choline (FCH) PET/MRI and (ii) to assess the impact of PET/MRI findings in patients with PCa who develop OMD using PSA response as a biomarker. Methods We retrospectively analyzed a cohort of 103 patients undergoing FCH PET/MRI for biochemical recurrence of PCa. The inclusion criteria were (1) previous radical prostatectomy (RP) with or without adjuvant radiotherapy (RT); (2) PSA levels available at the time of PET; (3) OMD, defined as a maximum of 5 lesions on PET/MRI; and (4) follow-up data available for at least 6 months after PET. All images were reviewed by two nuclear medicine physicians and interpreted with the support of two radiologists. Results Seventy patients were eligible for the study: 52 patients had a positive FCH PET/MRI and 18 had a negative scan. The overall PCa detection rates for MRI, PET, and PET/MRI were 65.7%, 37.1%, and 74.3%, respectively. Thirty-five patients were treated with radiotherapy (RT), 16 received hormonal therapy (HT), 3 had a combined therapy (RT + HT), and 16 (23%) underwent PSA surveillance. At follow-up, PSA levels decreased in 51 patients (73%), most of whom had been treated with RT or RT + HT. Therapeutic management was guided by PET/MRI in 74% of patients, which performed better than MRI alone (68% of patients). Conclusion FCH PET/MRI has a higher detection rate than MRI or PET alone for PCa patients with OMD and PSA levels > 0.5 ng/mL, prompting a better choice of treatment.

Efficacy of cholecystectomy in patients with positive HIDA Scans with typical or atypical biliary pain: A retrospective study

Introduction: Our investigation aimed to discover the benefits of performing cholecystectomy in patients who had a positive or negative HIDA scan result, presented with either typical or atypical biliary pain. Methods: We performed a retrospective analysis of medical records of patients who had a HIDA scan at Peninsula Health between 2012 and 2017, those who had a HIDA scan and cholecystectomy for biliary pain were selected for this study, and prospective analysis of patient reported outcome post cholecystectomy included. Results: In the past five years, 190 patients had had a HIDA scan to investigate biliary pain without a structural cause. Of those 190, 65 had a positive HIDA result and 20 of these patients went on to have a cholecystectomy. Of the latter, 17 who reported typical biliary pain had their pain resolved post-surgery but 2 out of 3 patients with atypical biliary pain had ongoing pain despite surgery (1 did not respond). Of the 125 patients with a negative HIDA scan, 14 proceeded with a cholecystectomy. Twelve patients had pre-operative typical biliary pain and 5 of these continued to have pain post-operatively. Finally, 1 of the 2 patients with atypical pain continued to have ongoing pain post-surgery. Conclusion: In summary, in patients without a structural cause for biliary pain HIDA scans and patient’s symptoms greatly aid in the decision-making process whether to proceed with a cholecystectomy, as a negative scan should prompt further clinical investigation before proceeding with surgery.

SAT0557 RESIDUAL DISEASE ACTIVITY IN ADULT-ONSET STILL’S DISEASE: QUALITATIVE AND QUANTITATIVE ANALYSIS OF A SERIES OF 18F FDG-PET/MR

Background:Adult-onset Still’s disease (AOSD) is a systemic autoinflammatory disorder characterized by episodes of spiking fever, the presence of an evanescent pink-salmon rash, arthritis/arthralgias, sore throat and increased inflammatory serum markers. The diagnosis is clinical and needs the exclusion of potential mimickers such as infections and lymphoproliferative disorders. Currently, a specific diagnostic test to assess the disease activity is not available.Objectives:To define the residual disease activity in AOSD and establish a possible response to therapy through18F-FDG PET/MR imaging technique.Methods:23 patients affected by AOSD and 24 controls underwent18F-FDG PET/MR between 2014 and 2018. A total of 5418F-FDG PET/MR were analysed. AOSD patients were diagnosed according to the Yamaguchi’s criteria and were in follow-up at the Rheumatology Unit of Padova University Hospital. The controls were chosen among non-AOSD patients with a previous diagnosis of solid tumors (lymphomas excluded). Aqualitative analysisof PET/RM carried out by a Nuclear Medicine Specialist and asemiquantitative analysiscarried out by measuring SUVs-to-liver (Standardized Uptake Value) for spleen, bone marrow (BM), lymph nodes and pharynx were performed. A SUVmax BM/SUVmean liver higher than 2.09 was set up as significant area of uptake for each organ considered. This threshold was calculated by adding the standard deviation multiplied by 2 at the mean ratio between SUVmax BM and SUVmean liver of the control group. The Pouchot score for disease activity was calculated for each subject. The distribution of the variables was investigated by Shapiro-Wilk test. The analysis of the association between the variables was carried out using the Mann-Whitney U test.Results:AOSD patients present areas of focal18F-FDG uptake mainly in BM, lymph nodes, pharynx, spleen and salivary glands. Sites of uptake in spleen were found in 3.3% of PET/MR, in BM in 23.3%, in lymph nodes in 23.3% and in pharynx in 36.6% of PET/RM respectively. Eleven/thirty (47.8%) patients were defined as “positive” since the uptake was higher than liver, and twelve/thirty (52.2%) were defined as “negative” since the uptake was lower than liver, regardless of SUVs and clinical manifestations. A semi-quantitative analysis assessed whether the values of the SUVmax BM/liver were higher than the cut-off of 2.09 in “positive” PET/MR and lower in the “negative” ones and if the clinical manifestations were present or absent in agreement with the evaluation of SUVs for each patient. BM was found to be active (SUVmax ratio > of 2.09) in 7 out of 11 patients when the PET/MR was defined “positive”, while only in 1 case out of 12 BM SUVmax was >2.09 when the exam was “negative”. Clinical manifestations were present in 10 out of 11 AOSD with a “positive” scan and in 7 out of 11 with both a “positive” scan and a SUV max BM/liver >2.09. Clinical manifestations were present in 1 out of 12 patients with a “negative” scan, while in 10 out of 12 cases with both a negative scan and a SUV max BM/liver <2.09 were absent. Six patients repeated PET/MR during follow-up. The values of the SUVmax BM/liver significantly decreased after anti IL-1β treatment with anakinra. In two cases in which anakinra was deferred, the BM SUVmax values exceeded the cut-off of 2.09 despite the patients did not complain any symptom or inflammation markers increase.Conclusion:18F FGD-PET/MR could be able to evaluate the disease activity in AOSD when clinical manifestations and serum markers are not sufficient to establish it. The uptake on BM seems quite sensitive in pointing out the disease severity and in assessing the response to anti IL-1β therapy.18F PET/MR is an accurate and repeatable method, however further studies are required to validate its applicability in routinary clinical practice.Disclosure of Interests:None declared

Association of Histological Findings with Tc-99m Sestamibi Parathyroid Imaging in Hyperfunctional Parathyroid Gland

Background: Hyperthyroidism is a relatively common disorder that results from increased production of parathormone. Tc-99m sestamibi (MIBI) scanning is used for localization of abnormal parathyroid gland, with high reported sensitivities. However, there exists a group of patients in whom MIBI scan is either equivocal or negative. Objectives: The aim of this study was to see association of the histological features of pathologic parathyroid gland with MIBI scan in hyperfunctional parathyroid gland. Methodology: This retrospective study was conducted with primary hyperthyroidism who underwent MIBI scan. The data were collected from the record from January 2012 to December 2014 for a period of two years. All patients underwent parathyroid surgery followed by histopathological examination. According to oxyphil cell distribution patients are divided in three groups. Group I comprised of >25.0% oxyphil cell; group II included the 25 to 75% oxyphil cell and group III included >75% of oxyphil cell. Result: A total 56 patients with hypercalcaemia and high serum parathyroid hormone (PTH) level were studied. Mean age was 41.3(±19.8) years with a range of 21 to 63 years. MIBI scan was true positive in 34(60.7%) cases and false negative in 22(39.3%) cases. In group I MIBI scan was true positive in 4(36.3%) cases and false negative in 7(63.7%) cases. In group II MIBI scan showed positive in 17(62.9%) cases and negative in 10(37.1%) cases. In group III out of 18 patients 13(72.2%) showed MIBI scan positive whereas, 5(27.8%) showed negative scan. The sensitivity was 36.3% in group I whereas, 62.9% and 72.2% in group II and group III respectively. Conclusion: Based on these findings, it could be say that Tc–99m setamibi uptake correlate with parathyroid oxyphil cell content, and false negative scan can occur with parathyroid glands containing predominantly clear cell.Journal of National Institute of Neurosciences Bangladesh, 2016;2(1):14-18

Sestamibi Positive Vs Negative Scan In Primary Hyperparathyroidism; A Clinical Dilemma

Objectives: In primary hyperthyroidism Tc-99m Sestamibi (MIBI) scanning is commonly used for localization of abnormal parathyroid gland and the reported sensitivity is very high. However, false negative scan remain a problem. We examined whether serum calcium and parathormone (PTH) level have any impact in the sensitivity of MIBI scan.Study design: A retrospective review of 55 patients with primary hyperparathyroidism who underwent MIBI scan from January 2012 to December 2014 were included in this study. All patients underwent parathyroid surgery followed by histopathological confirmation.Results: In total, 55 patients were studied. Mean age was 41.3 ± 19.8 years (range 21-63 years). MIBI scan was true positive in 37 cases and false negative in 18 cases. The sensitivity of MIBI scan was 67.2 %. Mean serum calcium level was 12.3 mg/ dL. More than 62.2 % of patients with calcium level greater than 12.3 mg/dL had a positive scan as compared with 37.8% of those with lesser value (P<0.05). Similarly a serum PTH level greater than 316 ± 139 pg/mL correlated with positive scans in 78.4 % as opposed to 21.6 % in those with lower levels (P< 0 .01).Conclusion: Lower calcium and PTH level significantly correlate with reduced sensitivity of MIBI scan. Although we did not find the best cut-off level of serum calcium and PTH level that can predict a positive scan.Bangladesh J. Nuclear Med. 17(2): 142-145, July 2014