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Purpose: The purposes was to build model incorporating PET +  computed tomography (CT) radiomics features from baseline PET/CT + clinical parameters to predict outcomes in patients with non-Hodgkin lymphomas., Methods: Cohort of 138 patients with complete clinical parameters and follow up times of 25.3 months recorded. Textural analysis of PET and manual correlating contouring in CT images analyzed using LIFE X software. Defined outcomes were overall survival (OS), disease free-survival, radiotherapy, and unfavorable response (defined as disease progression) assessed by end of therapy PET/CT or contrast CT. Univariable and multivariable analysis performed to assess association between PET, CT, and clinical., Results: Male ( P  = 0.030), abnormal lymphocytes ( P  = 0.030), lower value of PET entropy ( P  = 0.030), higher value of SHAPE sphericity ( P  = 0.002) were significantly associated with worse OS. Advanced stage (III or IV, P  = 0.013), abnormal lymphocytes ( P  = 0.032), higher value of CT gray-level run length matrix (GLRLM) LRLGE mean ( P  = 0.010), higher value of PET gray-level co-occurrence matrix energy angular second moment ( P  < 0.001), and neighborhood gray-level different matrix (NGLDM) busyness mean ( P  < 0.001) were significant predictors of shorter DFS. Abnormal lymphocyte ( P  = 0.033), lower value of CT NGLDM coarseness ( P  = 0.082), and higher value of PET GLRLM gray-level nonuniformity zone mean ( P  = 0.040) were significant predictors of unfavorable response to chemotherapy. Area under the curve for the three models (clinical alone, clinical + PET parameters, and clinical + PET + CT parameters) were 0.626, 0.716, and 0.759, respectively., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Purpose: To determine in a group of patients with progressive metastatic neuroendocrine tumors (PM-NETs) treated with 177Lu-DOTATATE whether a correlation exists between somatostatin receptor (SSTR)-2 expression in various tumors on baseline 68Ga-DOTATATE PET and their response to therapy. A secondary aim was to determine whether an association exists between tumor product of diameter (POD) and PET-derived Krenning score., Materials Methods: Patients treated PM-NETs who had SSTR-2 overexpression (SSTR-RADS 5) on screening 68Ga-DOTATATE PET and CT at baseline and 3 months after therapy completion were included. Marker lesions on baseline CT were reassessed on CT after therapy using adapted Southwest Oncology Group solid tumor evaluation criteria. For each lesion, bidimensional diameter on CT and SSTR expression on PET (SSTR-RADS uptake score & PET-derived Krenning score) were recorded. Logistic regression models fitted through generalized estimating equations were used to assess for an association between SSTR expression and response to therapy, or lesion's POD., Results: Forty-one patients with SSTR-RADS 5 PM-NETs treated with 177Lu-DOTATATE were included. There were 135 marker lesions (mean 3.2 lesions/patient) with Krenning score of 4 (n = 74), 3 (n = 44) or 2 (n = 17). There was no association found between SSTR-2 expression, as determined by SSTR-RADS uptake score or PET-derived Krenning score, and POD or response to therapy., Conclusion: In patients with SSTR-RADS 5 PM-NETs treated with 177Lu-DOTATATE, there was similar response to therapy for all lesions with PET-generated Krenning score ≥2. No correlation was found between lesion's POD and level of tracer uptake., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Objectives: The aim of the study was to evaluate preliminary feasibility of 18F-FDG-PET/MRI in differentiation of pancreatic serous cystic neoplasms (SCNs) from non-SCNs., Methods: From August 2017 to June 2019, 10 patients (3 men, 7 women; mean age, 63 years) previously diagnosed with pancreatic cystic neoplasm underwent simultaneous 18F-FDG-PET/MRI prospectively on an integrated 3-Tesla hybrid PET/MRI scanner. PET images were analyzed visually and semiquantitatively measuring standardized uptake values (SUV) including lesion SUVmax and SUVmean, lesion to pancreas and lesion to liver SUVmax and SUVmean ratio independent of MRI diagnosis. The reference standard for lesion diagnosis was by MRI features and interval follow-up., Results: Visual assessment of PET images demonstrated uptake in 57% of SCNs. Lesion to liver SUVmax ratio of ≥0.5 showed the highest accuracy (90%) and area under the curve (0.9) followed by lesion SUVmax of ≥1.6 and lesion to pancreas SUVmax ratio of ≥0.77 for diagnosis of SCN. The sensitivity for lesion SUVmax of ≥1.6 was less than two other ones (71 versus 100%). All non-SCNs exhibited SUVmax value less than 1.6 while 33 and 66% demonstrated lesion to liver SUVmax ratio of >0.5 and lesion to pancreas SUVmax ratio of >0.77, respectively. PET/MRI specificity was 67, 100, 67 and 33% through lesion to liver SUVmax ratio, lesion SUVmax, lesion SUVmean and lesion to pancreas SUVmax ratio, respectively, for diagnosis of SCN., Conclusion: Preliminary results show that PET/MRI utilization is promising for differentiation of pancreatic SCN from non-SCN lesions. This could reduce need for surveillance imaging or avoidance of unnecessary intervention in pancreatic cystic neoplasms with uncertain diagnoses.

Objectives: To evaluate the impact of F-fluorodeoxyglucose PET/CT examinations on the management of patients with plasma cell disorders., Methods: This is a retrospective review of patients in a provincial database with PET/CT performed for plasma cell disorders between 2011 and 2018. The impact of PET/CT on actual patient management and outcome was assessed by two independent readers who compared planned pre-PET/CT management, documented at time of PET/CT requisition, to actual management received through linkages to administrative databases. PET/CT was considered of high impact if it altered the provision of active treatment, changed the modality of treatment or chemotherapy regimen. Change in management and the proportion of patients with high impact PET/CT were assessed., Results: There were 44 patients with plasma cell disorders, including multiple myeloma, solitary plasmacytoma, Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal protein, Skin changes syndrome, or monoclonal gammopathy of undetermined significance or biclonal gammopathy of undetermined significance. Management was altered after 38/56 (67.9%) PET/CT scans. Considering just the initial PET/CT scan in patients who underwent multiple scans, 31/44 (70.5%) patients had their management altered subsequent to PET/CT., Conclusion: PET/CT resulted in a change in planned management in more than two-thirds of patients with plasma cell disorders in the current selected patient cohort. These results should be validated in a larger prospective trial.

The aim of the present study was to assess the ability of a novel bone imaging technique to diagnose accurately the cause for back pain as an isolated and presenting complaint in adolescents. An integrated 18F-fluoride positron-emission tomography-computed tomography (PET-CT) study was performed at the same setting without changing the patients' position, followed by generation of fused images of functional and anatomical data. Fifteen subjects were included in the study. The interpretation of PET-CT fused images was based on increased 18F-fluoride uptake and the corresponding CT-located abnormality. Ten patients had positive findings that included 4 cases of spondylolysis (3 of them active), 3 frank fractures (2 of the transverse process and 1 of the facet), 2 osteoid osteomas, 1 osteitis pubis, 1 sacroiliitis, and 2 herniated disks. Three patients presented 2 coexisting pathologies. Treatment was tailored based on final diagnosis. In 5 patients, in whom no abnormality was identified, the back pain resolved spontaneously. The 18F-fluoride PET-CT can detect spinal lesions with high diagnostic accuracy in adolescents with back pain. Considering the associated costs and radiation exposure, it should be used at present only in cases of long-standing and disabling back pain in which other imaging modalities were inconclusive.

Objective: To assess the role of 18F-Fluorodeoxyglucose (18F-FDG) PET/CT in pediatric patients with Hodgkin disease (HD) and non-Hodgkin lymphoma (NHL)., Materials and Methods: 31 patients, mean age 12.9 +/- 5.1, HD (n = 24), and NHL (n = 7) underwent 18F-FDG PET/CT at diagnosis (n = 31 studies) and later in the course of the disease (n = 75 studies). The findings of PET/CT were correlated with diagnostic CT and clinical follow-up., Results: PET/CT findings resulted in a change of disease staging in 10 patients (32.3%), upstaging in 7 (22.6%) and downstaging in 3 (9.6%). On a lesion analysis, 164 disease sites were detected by PET/CT of which 38 were overlooked by DCT. At mid-treatment, PET was negative in 28 out of 31 patients (90%) with negative predictive value of 96% as all latter patients except for 1, were disease free (mean 15.4 +/- 8.8 months). The positive predictive value of persistent increased 18F-FDG uptake was 100% as 3 patients with latter findings had active disease. On the CT part, 76 residual masses were identified in 22 patients. Increased 18F-FDG uptake was detected in 11 masses in 4 patients who had active disease. Remaining 65 PET negative masses were false positive findings. The positive predictive value of residual CT mass was 14%., Conclusions: PET/CT is associated with change in staging in approximately 1 out of 3 pediatric patients with HD and NHL. When used for monitoring response to treatment, a negative study is associated with disease-free period, even when residual mass is detected. A positive PET study indicates residual malignant disease.

Our objective was to evaluate the toxicity and antitumor efficacy of concurrent biochemotherapy in metastatic melanoma patients and the effectiveness of adding temozolomide to protect the brain from metastases. Twenty-three patients with advanced inoperable melanoma were hospitalized for 5-6 days for the following treatment: cisplatin 20 mg/m daily for 4 days, vinblastine 1.6 mg/m daily for 4 days and oral temozolomide 250 mg/m daily for 5 days, with 18 x 10 IU/m intravenous interleukin-2 by continuous infusion for 4 days (the dose was cut daily by 50%) and 5 x 10 U/m interferon-alfa subcutaneously daily for 5 days, repeated at 28-day intervals for a maximum of nine courses. According to the standard World Health Organization response criterion, the objective response rate was 43.4% and the median survival was 18.6 months. All but one patient survived for more than 12 months, and no responding patient progressed first in the brain. Substituting dacarbazine by temozolomide in the MD Anderson melanoma section protocol appears to offer protection against dissemination of brain metastases, equal activity in the periphery and a possible lower incidence of toxicity due to the oral route.

Objectives: To determine if there is added value to oncology studies performed with a dedicated in-line positron emission tomography (PET)/computed tomography (CT) scanner as compared with PET read side by side with diagnostic CT (DCT)., Methods: Forty-one consecutive oncology patients referred for PET/CT who had contemporary DCT scans for review were enrolled. Body regions assessed on a DCT scan were assessed on PET/CT and by side-by-side reading of PET and DCT (SBS PET/DCT). Lesions identified on DCT, the CT portion of PET/CT, SBS PET/DCT, and the reading of fused PET/CT images were scored as benign or malignant. The PET portion of the PET/CT study was read by 2 teams: the first read the SBS PET/DCT scan and the other read the complete fused PET/CT scan. For discordant lesions, the final diagnosis was determined by pathologic findings (n = 6) or imaging follow-up (n = 21)., Results: Twenty-seven (16.1%) of the 168 lesions were discordant when comparing analysis of fused PET/CT and SBS PET/DCT. Sixteen (9.5%) were fundamentally discordant, and 11(6.6%) were discordant in degree of confidence. For all discordant lesions only, the sensitivity, specificity, negative predictive value, positive predictive value, and accuracy for PET/CT were 100%, 33%, 100%, 94%, and 78%, respectively, and for SBS PET/DCT, they were 38%, 50%, 19%, 73%, and 30%, respectively (P < 0.001 for sensitivity, P = not specific for specificity). The 2 main causes for misclassification on SBS PET/DCT were incorrect localization (n = 12) and changes occurring in the time gap between DCT and PET/CT (n = 4)., Conclusions: In-line PET/CT offers better lesion localization in comparison to the visual fusion of PET and CT, especially for small lymph nodes, lesions adjacent to mobile organs, or lesions adjacent to the chest or abdominal wall.

Objectives: We sought to define an accurate diagnostic approach for differentiating benign from malignant pleural effusion on positron emission tomography-computed tomography (PET-CT)., Material and Methods: PET-CT studies of 31 patients with primary extrapleural malignancy and pleural effusion were reviewed retrospectively. CT parameters assessed were size and density (Hounsfield units, or HU) of the effusion and density (HU) and morphology of any solid pleural abnormality. Interpretation of PET data included review of the attenuation-corrected and nonattenuation-corrected images., Results: PET-CT parameters that were found to be significant in identifying malignant pleural effusion included focal increased uptake of 18-fluorodeoxyglucose in the pleura (P<0.0001) and the presence of solid pleural abnormalities on CT (P<0.002): the sensitivity was 86% and 71%, respectively, and the specificity was 90% for each of the 2 parameters. A PET-CT pattern composed of pleural uptake and increased effusion activity on nonattenuation-corrected images was associated with sensitivity of 95%, specificity of 80%, positive predictive value of 91%, negative predictive value of 89%, and accuracy of 90%., Conclusions: On PET-CT, the presence of concomitant pleural abnormalities is the most accurate criterion in determining the malignant nature of pleural effusion.

Rationale and Objectives: A new method of measurement, simultaneous multigated spectral Doppler imaging (MSDI), was used to quantify the hemodynamic changes in kidneys after administration of captopril., Methods: Forty kidneys in 22 hypertensive patients were included in the study. All underwent MSDI and scintigraphy before and after administration of captopril., Results: With scintigraphy used as the gold standard for diagnosing renal artery stenosis (RAS), three kidneys were found to be positive for RAS. Multigated spectral Doppler imaging detected a decrease in the resistive index after administration of captopril in all patients with RAS and correctly excluded RAS in one patient who was diagnosed as having RAS on scintigraphy. The resistive index was increased after captopril administration in normally functioning kidneys and was unchanged in kidneys with impaired function., Conclusions: With further supportive evidence, MSDI may prove to be a powerful tool for the acquisition of resistive index information and may increase the value of the resistive index as a physiological hemodynamic parameter in the evaluation of normal and abnormal conditions.