Baseline circulating tumour DNA and total metabolic tumour volume as early outcome predictors in aggressive large B-cell lymphoma. A real-world 112-patient cohort.

Approximately 20%-50% of patients with large B-cell lymphoma (LBCL) experience poor outcomes. We aimed to evaluate the combined prognostic value of circulating tumour DNA (ctDNA) and total metabolic tumour volume (TMTV) in LBCL. This observational single-centre study included 112 newly diagnosed LBCL patients, receiving R-CHOP/R-CHOP-like chemotherapies. CtDNA load was calculated following next-generation sequencing of cell-free DNA (cfDNA) using a targeted 40-gene lymphopanel. TMTV was measured using a fully automated artificial intelligence-based method for lymphoma lesion segmentation. CtDNA was detected in cfDNA samples from 95 patients with a median concentration of 3.15 log haploid genome equivalents per mL. TMTV measurements were available for 102 patients. The median TMTV was 501 mL. High ctDNA load (>3.57 log hGE/mL) or high TMTV (>200 mL) were associated with shorter 1-year PFS (44% vs. 83%, p < 0.001 and 64% vs. 97%, p = 0.002, respectively). When combined, three prognostic groups were identified. The shortest PFS was observed when both TMTV and ctDNA load were high (p < 0.001). Even with a short follow up, combining ctDNA load with TMTV improved the risk stratification of patients with aggressive LBCL. In the near future, very high-risk patients could benefit from CAR T-cell therapy or bispecific antibodies as first-line treatments.

Obinutuzumab vs rituximab for advanced DLBCL: a PET-guided and randomized phase 3 study by LYSA.

Rituximab plus polychemotherapy is the standard of care in diffuse large B-cell lymphoma (DLBCL). GAINED, a randomized phase 3 trial, compared obinutuzumab to rituximab. Transplant-eligible patients (18-60 years) with an untreated age-adjusted International Prognostic Index (aaIPI) score ≥1 DLBCL were randomized (1:1) between obinutuzumab or rituximab and stratified by aaIPI (1; 2-3) and chemotherapy regimen (doxorubicin, cyclophosphamide, prednisone plus vindesine, bleomycin [ACVBP] or vincristine [CHOP]). Consolidation treatment was determined according to response to interim positron emission tomography (PET). Responders after cycle 2 and 4 (PET2-/PET4-) received immunochemotherapy. Responders after only cycle 4 (PET2+/4-) received transplantation. The primary objective was an 8% improvement (hazard ratio [HR] = 0.73; 80% power; α risk, 2.5%; 1-sided) in 2-year event-free survival (EFS) in the obinutuzumab arm. From September 2012, 670 patients were enrolled (obinutuzumab, n = 336; rituximab, n = 334). A total of 383 (57.2%) were aaIPI 2-3, 339 (50.6%) received CHOP. Median follow-up was 38.7 months. The 2-year EFS was similar in both groups (59.8% vs 56.6%; P = .123; HR = 0.88). The 2-year PFS in the whole cohort was 83.1% (95% confidence interval, 80% to 85.8%). PET2-/4- and PET2+/4- had similar 2-year progression-free survival (PFS) and overall survival (OS): 89.9% vs 83.9% and 94.8% vs 92.8%. The 2-year PFS and OS for PET4+ patients were 62% and 83.1%. Grade 3-5 infections were more frequent in the obinutuzumab arm (21% vs 12%). Obinutuzumab is not superior to rituximab in aaIPI ≥1 DLBCL transplant-eligible patients. This trial was registered at www.clinicaltrials.gov as #NCT01659099.

Epithelioid glioblastoma diagnosed 70 years after craniofacial radiotherapy.

The authors report a rare case of most likely radiation-induced glioma (RIG) with epithelioid features and the presence of molecular features consistent with RIG. This occurred 70 years after craniofacial brachytherapy. Such a late development of radiation-induced glioblastoma (RIGBM) and the advanced age of presentation for an epithelioid glioblastoma are both unique in the literature. Despite not receiving the full course of adjuvant chemotherapy after surgery and radiotherapy, the patient displayed no signs of recurrence during a 5-year follow-up. RIGBM should be further studied to reveal potential unique clinical and molecular characteristics, as well as to better predict survival and treatment response.

Chest PET/MRI in Solid Cancers: Comparing the Diagnostic Performance of a Free-Breathing 3D-T1-GRE Stack-of-Stars Volume Interpolated Breath-Hold Examination (StarVIBE) Acquisition With That of a 3D-T1-GRE Volume Interpolated Breath-Hold Examination (VIBE) for Chest Staging During Whole-Body PET/MRI.

BACKGROUND: Whole-body positron emission tomography/magnetic resonance imaging (WB-PET/MRI) is increasingly used in oncology. However, chest staging remains challenging. PURPOSE: To compare the diagnostic performance of a free-breathing 3D-T1-GRE stack-of-stars volume interpolated breath-hold examination (StarVIBE) with that of a 3D-T1-GRE volume interpolated breath-hold examination (VIBE) during WB-PET/MRI for chest staging. STUDY TYPE: Retrospective, cohort study. POPULATION: One hundred and twenty-three patients were referred for initial staging of solid cancer, 46 of whom had pulmonary nodules and 14 had pulmonary metastasis. FIELD STRENGTH/SEQUENCE: Free-breathing 3D-T1-GRE stack-of-stars (StarVIBE) and Cartesian 3D-T1-GRE VIBE at 3.0 T. ASSESSMENT: Image quality was assessed using a 4-point scale and using the signal-to-noise ratio (SNR) of lung parenchyma and contrast-to-noise ratio (CNR) of pulmonary nodules. Diagnostic performances of both sequences were determined by three independent radiologists for detection of pulmonary nodules, lymph node involvement, and bone metastases using chest CT, pathology, and follow-up as reference standards. STATISTICAL TESTS: Paired Student's t-test; chi-squared; Fisher's exact test. A P value <0.05 was considered statistically significant. RESULTS: StarVIBE quality was judged as better in 34% of cases and at least equivalent to VIBE in 89% of cases, with significantly higher quality scores (4 [4-4] vs. 3 [3-4], respectively). SNR and CNR values were significantly higher with StarVIBE (8 ± 1.3 and 9.7 ± 4.6, respectively) than with VIBE (1.8 ± 0.2 and 5.5 ± 3.3, respectively). Compared to VIBE, StarVIBE showed significantly higher sensitivity (73% [95% CI 62-82] vs. 44% [95% CI 33-55], respectively) and specificity (95% [95% CI 88-99] vs. 67% [95% CI 56-77]) for pulmonary nodules detection and significantly higher sensitivity (100% [95% CI 89-100] vs. 67% [95% CI 48-82], respectively) for detection of lymph node involvement. Sensitivities for bone metastases detection were not significantly different (100% [95% CI 88-100] vs. 82% [95% CI 63-94], P = 0.054). DATA CONCLUSION: Owing to improved SNR and CNR and spatial resolution, a free-breathing 3D stack-of-stars T1-GRE sequence improves chest staging in comparison with standard 3D-T1-GRE VIBE and may be integrated in WB-PET/MRI acquisitions for initial staging of solid cancer. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Optimization of whole-body 2-[18F]FDG-PET/MRI imaging protocol for the initial staging of patients with myeloma.

OBJECTIVE: To determine the optimal 2-[18F]FDG-PET/MRI imaging protocol for the initial staging of patients with suspected or confirmed multiple myeloma. METHODS: Radiologists and nuclear medicine specialists reviewed all PET/MRI exams of 104 patients with a monoclonal gammopathy (MG). The presence of focal and diffuse bone marrow involvement (BMI) was assessed using 4 different image datasets: WB-MRI, PET, WB-PET/MRI, and WB-DCE-PET/MRI. A reference standard was established by a panel review of all baseline and follow-up imaging, and biological and pathological information. The diagnostic performance for each image dataset to detect BMI was evaluated and compared (Fisher's exact test). RESULTS: Sensitivity, specificity, and accuracy for focal BMI of WB-MRI was 87%, 97%, and 92%; of PET was 78%, 97%, and 95%; of WB-PET/MRI was 93%, 97%, and 95%; and of WB-DCE-PET/MRI was 93%, 97%, and 95%, respectively. WB-PET/MRI and WB-DCE-PET/MRI were statistically superior to PET (p = 0.036) without decreasing specificity. The sensitivity, specificity, and accuracy of WB-MRI for diffuse BMI detection was 91%, 80%, and 85%; of 3DT1-PET was 53%, 89%, and 74%; of WB-PET/MRI was 98%, 66%, and 79%; and of WB-DCE-PET/MRI was 98%, 59%, and 75%, respectively. PET lacked sensitivity compared to all other dataset studies (p < 0.0001). WB-MRI had the best accuracy without reaching statistical significance when compared to the other datasets. CONCLUSION: The WB-PET/MRI dataset including T1 and T2 Dixon, WB-DWI, and PET images provides optimal diagnostic performance to detect both focal lesions and diffuse BMI, with limited added value of WB-DCE for baseline staging of patients with MG. Key Points • The combination of morphological and functional MRI sequences and metabolic (2-[18F]FDG-PET) images increases the diagnostic performance of PET/MRI to detect focal bone lesions. • The adjunction of dynamic contrast-enhanced sequences did not improve diagnostic performance.

Autofluorescence imaging within the liver: a promising tool for the detection and characterization of primary liver tumors.

OBJECTIVES: To assess the performance of 405 nm-induced autofluorescence for the characterization of primary liver nodules on ex vivo resected specimens. MATERIALS AND METHODS: Forty resected liver specimens bearing 53 primary liver nodules were included in this IRB-approved prospective study. Intratissular spectroscopic measurements were performed using a 25-G fibered-needle on all ex vivo specimens: 5 autofluorescence measurements were performed in both nodules and adjacent parenchyma. The spectra derivatives of the 635 and 670 nm autofluorescence peaks observed in nodules and in adjacent liver parenchyma were compared (Kruskal-Wallis and Mann-Whitney when appropriate). RESULTS: A total of 42 potentially evolutive primary liver nodules-34 hepatocellular carcinomas, 4 intrahepatic cholangiocarcinomas, 4 hepatocellular adenomas-and 11 benign nodules-5 focal nodular hyperplasias, 6 regenerative nodules-were included. Both 635 and 670 nm Δderivatives were significantly higher in benign as compared to potentially evolutive (PEV) nodules (respectively 32.9 ± 4.5 vs 15.3 ± 1.4; p < 0.0001 and 5.7 ± 0.6 vs 2.5 ± 0.1; p < 0.0001) with respective sensitivity and specificity of 78% and 91% for distinguishing PEV from benign nodules. CONCLUSION: 405 nm-induced autofluorescence enables the discrimination of benign from PEV primary liver nodules, suggesting that autofluorescence imaging could be used to optimize US targeted liver biopsies. KEY POINTS: • 405 nm-induced autofluorescence can distinguish liver tumors from the adjacent liver parenchyma. • The analysis of autofluorescence imaging observed within primary liver tumors can discriminate benign tumors from those requiring follow-up or targeted liver biopsy. • In current practice, autofluorescence imaging could be embedded within biopsy needle, to enable, in addition to ultrasound guidance, optimal targeting of liver nodules which could optimize tissue sampling.

Utility of Early Posttreatment PET/CT Evaluation Using FDG or 18F-FCH to Predict Response to 90Y Radioembolization in Patients With Hepatocellular Carcinoma.

BACKGROUND. Assessment of hepatocellular carcinoma (HCC) treatment response after transarterial radioembolization (TARE) is challenging, because response by conventional imaging criteria may not become apparent until 6 months after treatment. Though HCC exhibits variable avidity for FDG, some cases of HCC without avidity for FDG show avidity for 18F-fluorocholine (18F-FCH). OBJECTIVE. The purpose of this study was to evaluate the utility of early posttreatment evaluation by PET/CT using FDG or 18F-FCH to predict 6-month treatment response and survival after TARE in patients with HCC. METHODS. This retrospective study included 37 patients (mean age, 67 years; 34 men, three women) with documented HCC treated by TARE who underwent both pre-treatment FDG PET/CT and 18F-FCH PET/CT and early FDG PET/CT and/or 18F-FCH PET/CT 4-8 weeks after treatment; FDG PET/CT and 18F-FCH PET/CT examinations were performed on separate dates. Only one of 73 initially identified potentially eligible patients was excluded because of lack of HCC avidity for both FDG and 18F-FCH. Response assessment by modified RECIST (mRECIST) on multiphase CT or MRI was performed at 1 month and 6 months in 23 patients. Early responses seen on PET/CT and 1-month mRECIST response were assessed as predictors of 6-month mRECIST response. Univariable and multivariable predictors of overall survival (OS) were identified. RESULTS. On pretreatment PET/CT, 28 (76%) patients were FDG-positive (showed visual uptake on FDG PET/CT and tumor-to-normal liver ratio > 1.15), 15 (41%) were FCH-positive (showed visual uptake on 18F-FCH PET/CT), and six (16%) were both FDG-positive and FCH-positive. Twelve of 28 FDG-positive HCCs exhibited early response by FDG PET/CT; seven of 15 FCH-positive HCCs exhibited early response by 18F-FCH PET/CT. Twelve (52%) patients exhibited 6-month mRECIST response. Response seen on early posttreatment PET/CT exhibited 100% (12/12) sensitivity and 100% (11/11) specificity for 6-month mRECIST response, whereas 1-month mRECIST response exhibited 67% (8/12) sensitivity and 100% (11/11) specificity for 6-month mRECIST response. Response seen on early posttreatment PET/CT was a significant independent predictor of OS on univariable (hazard ratio [HR], 0.4; 95% CI, 0.2-0.9; p = .03) and multivariable (HR, 0.2; 95% CI, 0.1-0.8; p = .01) analyses. CONCLUSION. Early evaluation after TARE by PET/CT using FDG or 18F-FCH may pre dict 6-month response and OS in patients with HCC. CLINICAL IMPACT. Early posttreatment evaluation with PET/CT could help more reliably identify true nonresponders after TARE, which in turn could prompt early response-adapted therapeutic management.

Fully automatic segmentation of diffuse large B cell lymphoma lesions on 3D FDG-PET/CT for total metabolic tumour volume prediction using a convolutional neural network.

PURPOSE: Lymphoma lesion detection and segmentation on whole-body FDG-PET/CT are a challenging task because of the diversity of involved nodes, organs or physiological uptakes. We sought to investigate the performances of a three-dimensional (3D) convolutional neural network (CNN) to automatically segment total metabolic tumour volume (TMTV) in large datasets of patients with diffuse large B cell lymphoma (DLBCL). METHODS: The dataset contained pre-therapy FDG-PET/CT from 733 DLBCL patients of 2 prospective LYmphoma Study Association (LYSA) trials. The first cohort (n = 639) was used for training using a 5-fold cross validation scheme. The second cohort (n = 94) was used for external validation of TMTV predictions. Ground truth masks were manually obtained after a 41% SUVmax adaptive thresholding of lymphoma lesions. A 3D U-net architecture with 2 input channels for PET and CT was trained on patches randomly sampled within PET/CTs with a summed cross entropy and Dice similarity coefficient (DSC) loss. Segmentation performance was assessed by the DSC and Jaccard coefficients. Finally, TMTV predictions were validated on the second independent cohort. RESULTS: Mean DSC and Jaccard coefficients (± standard deviation) in the validations set were 0.73 ± 0.20 and 0.68 ± 0.21, respectively. An underestimation of mean TMTV by - 12 mL (2.8%) ± 263 was found in the validation sets of the first cohort (P = 0.27). In the second cohort, an underestimation of mean TMTV by - 116 mL (20.8%) ± 425 was statistically significant (P = 0.01). CONCLUSION: Our CNN is a promising tool for automatic detection and segmentation of lymphoma lesions, despite slight underestimation of TMTV. The fully automatic and open-source features of this CNN will allow to increase both dissemination in routine practice and reproducibility of TMTV assessment in lymphoma patients.

18F-sodium fluoride PET/MRI myocardial imaging in patients with suspected cardiac amyloidosis.

BACKGROUND: We evaluated the diagnostic performance of 18F-NaF PET/MRI in patients with suspected cardiac amyloidosis (CA). METHODS: Twenty-seven consecutive patients underwent myocardial PET 1 hour after injection of 4 MBq/kg 18F-NaF with simultaneous MRI including cine-MRI, T1 and T2 mapping, first-pass and late gadolinium enhancement (LGE). 18F-NaF uptake was measured visually and semi-quantitatively by calculating myocardium-to-blood pool (M/B) ratios. CA was confirmed histologically. RESULTS: Transthyretin (TTR)-CA was diagnosed in 16 patients, light-chain (AL)-CA in 7, and no-CA in 4. Visual interpretation of 18F-NaF images revealed a relative increase in myocardial uptake in only 3 patients, all with TTR CA, and a relative decrease in 13, including 7 AL CA, 3 no-CA, and 3 TTR CA. M/B ratios were significantly higher in TTR CA (1.00 ± 0.12) than in AL CA (0.81 ± 0.06, P = 0.001) or in no-CA (0.73 ± 0.16, P = 0.006). The optimal M/B cut-off to distinguish TTR CA from AL CA was ≥ 0.90 (Fischer, P = 0.0005). By comparison, classification of patients using 99mTc-HMDP heart-to-mediastinum ratios with the previously published cut-off ≥ 1.21 reached higher significance (P < 0.0001). Among MRI parameters, myocardial T1, LGE score, and extracellular volume were higher in CA than in no-CA patients, 1409 ± 76 vs 1278 ± 35 ms (P = 0.004), 10.35 ± 5.30 vs 3.50 ± 3.42 (P = 0.03), and 46 ± 10 vs 33 ± 8 % (P = 0.01), respectively. CONCLUSION: 18F-NaF PET/MRI shows good diagnostic performance when semi-quantification is used. However, contrast is low and visual interpretation may be challenging in routine. PET/MRI could constitute a one-stop-shop evaluation of amyloid load and cardiac function in patients needing rapid work-up.

Extracardiac soft tissue uptake, evidenced on early 99mTc-HMDP SPECT/CT, helps typing cardiac amyloidosis and demonstrates high prognostic value.

PURPOSE: Increased cardiac uptake (CU) on early-phase 99mTc-HMDP scintigraphy has demonstrated diagnostic and prognostic values in amyloid transthyretin (ATTR) cardiac amyloidosis (CA). Extracardiac uptake (ECU) has been poorly studied. We assessed the clinical value of ECU, in combination with CU, on 99mTc-HMDP scintigraphy using a novel Methodological Amyloidosis Diagnostic Index (MADI). METHODS: We reviewed all patients referred for suspicion of CA, who underwent 99mTc-HMDP scintigraphy over an 8-year period. ECU, CU, and MADI were determined: MADI0 = neither ECU or CU, MADI1 = ECU alone, MADI2 = CU alone, and MADI3 = ECU + CU. RESULTS: Of 308 eligible patients, 247 had CA, including 75 ATTRv, 107 ATTRwt, and 65 light-chain (AL), while 61 had another cardiopathy (controls). ECU was observed in 29% of CA and 3% of controls. Most frequent sites of ECU were pleuropulmonary (16% of CA, 3% of controls) followed by the digestive tract and subcutaneous tissues. The liver and spleen ECU was only observed in AL-CA (n = 8). CU was only observed in CA patients (n = 187), of whom 182 had ATTR-CA vs. 5 AL-CA, P < 0.001. MADI0 was only observed in controls (97%) and in AL-CA (60%). MADI1 was mainly observed in AL-CA (positive predictive value, PPV = 91%) while MADI2/3 were more frequent in ATTR-CA (PPV = 97%), P < 0.0001. MADI > 0 vs. MADI0 in AL and MADI3 vs. MADI2 in ATTR were associated with a worse prognosis (P = 0.03 and P = 0.002, respectively). CONCLUSIONS: ECU combined with CU demonstrates high diagnostic and prognostic values in CA patients. MADI seems an easy and reliable score in clinical practice.

Good clinical practice recommendations for the use of PET/CT in oncology.

Positron emission tomography/computed tomography (PET/CT) is a nuclear medicine functional imaging technique with proven clinical value in oncology. PET/CT indications are continually evolving with fresh advances made through research. French practice on the use of PET in oncology was framed in recommendations based on Standards-Options-Recommendations methodology and coordinated by the French federation of Comprehensive Cancer Centres (FNLCC). The recommendations were originally issued in 2002 followed by an update in 2003, but since then, a huge number of scientific papers have been published and new tracers have been licenced for market release. The aim of this work is to bring the 2003 version recommendations up to date. For this purpose, a focus group was set up in collaboration with the French Society for Nuclear Medicine (SFMN) to work on developing good clinical practice recommendations. These good clinical practice recommendations have been awarded joint French National Heath Authority (HAS) and French Cancer Institute (INCa) label status-the stamp of methodological approval. The present document is the outcome of comprehensive literature review and rigorous appraisal by a panel of experts, organ specialists, clinical oncologists, surgeons and imaging specialists. These data were also used for the EANM referral guidelines.

Prognostic value of anthropometric measures extracted from whole-body CT using deep learning in patients with non-small-cell lung cancer.

INTRODUCTION: The aim of the study was to extract anthropometric measures from CT by deep learning and to evaluate their prognostic value in patients with non-small-cell lung cancer (NSCLC). METHODS: A convolutional neural network was trained to perform automatic segmentation of subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), and muscular body mass (MBM) from low-dose CT images in 189 patients with NSCLC who underwent pretherapy PET/CT. After a fivefold cross-validation in a subset of 35 patients, anthropometric measures extracted by deep learning were normalized to the body surface area (BSA) to control the various patient morphologies. VAT/SAT ratio and clinical parameters were included in a Cox proportional-hazards model for progression-free survival (PFS) and overall survival (OS). RESULTS: Inference time for a whole volume was about 3 s. Mean Dice similarity coefficients in the validation set were 0.95, 0.93, and 0.91 for SAT, VAT, and MBM, respectively. For PFS prediction, T-stage, N-stage, chemotherapy, radiation therapy, and VAT/SAT ratio were associated with disease progression on univariate analysis. On multivariate analysis, only N-stage (HR = 1.7 [1.2-2.4]; p = 0.006), radiation therapy (HR = 2.4 [1.0-5.4]; p = 0.04), and VAT/SAT ratio (HR = 10.0 [2.7-37.9]; p < 0.001) remained significant prognosticators. For OS, male gender, smoking status, N-stage, a lower SAT/BSA ratio, and a higher VAT/SAT ratio were associated with mortality on univariate analysis. On multivariate analysis, male gender (HR = 2.8 [1.2-6.7]; p = 0.02), N-stage (HR = 2.1 [1.5-2.9]; p < 0.001), and the VAT/SAT ratio (HR = 7.9 [1.7-37.1]; p < 0.001) remained significant prognosticators. CONCLUSION: The BSA-normalized VAT/SAT ratio is an independent predictor of both PFS and OS in NSCLC patients. KEY POINTS: • Deep learning will make CT-derived anthropometric measures clinically usable as they are currently too time-consuming to calculate in routine practice. • Whole-body CT-derived anthropometrics in non-small-cell lung cancer are associated with progression-free survival and overall survival. • A priori medical knowledge can be implemented in the neural network loss function calculation.

Hepatobiliary MR contrast agent uptake as a predictive biomarker of aggressive features on pathology and reduced recurrence-free survival in resectable hepatocellular carcinoma: comparison with dual-tracer 18F-FDG and 18F-FCH PET/CT.

OBJECTIVES: To compare the performance of the quantitative analysis of the hepatobiliary phase (HBP) tumor enhancement in gadobenate dimeglumine (Gd-BOPTA)-enhanced MRI and of dual-tracer 18F-FDG and 18F-fluorocholine (FCH) PET/CT for the prediction of tumor aggressiveness and recurrence-free survival (RFS) in resectable hepatocellular carcinoma (HCC). METHODS: This retrospective, IRB approved study included 32 patients with 35 surgically proven HCCs. All patients underwent Gd-BOPTA-enhanced MRI including delayed HBP images, 18F-FDG PET/CT, and (for 29/32 patients) 18F-FCH PET/CT during the 2 months prior to surgery. For each lesion, the lesion-to-liver contrast enhancement ratio (LLCER) on MRI HBP images and the SUVmax tumor-to-liver ratio (SUVT/L) for both tracers were calculated. Their predictive value for aggressive pathological features-including the histological grade and microvascular invasion (MVI)-and RFS were analyzed and compared using area under receiver operating characteristic (AUROC) curves and Cox regression models, respectively. RESULTS: The AUROCs for the identification of aggressive HCCs on pathology with LLCER, 18F-FDG SUVT/L, and 18F-FCH SUVT/L were 0.92 (95% CI 0.78, 0.98), 0.89 (95% CI 0.74, 0.97; p = 0.70), and 0.64 (95% CI 0.45, 0.80; p = 0.035). At multivariate Cox regression analysis, LLCER was identified as an independent predictor of RFS (HR (95% CI) = 0.91 (0.84, 0.99), p = 0.022). LLCER - 4.72% or less also accurately predicted moderate-poor differentiation grade (Se = 100%, Sp = 92.9%) and MVI (Se = 93.3%, Sp = 60%) and identified patients with poor RFS after surgical resection (p = 0.030). CONCLUSIONS: HBP tumor enhancement after Gd-BOPTA injection may help identify aggressive HCC pathological features, and patients with reduced recurrence-free survival after surgical resection. KEY POINTS: • In patients with resectable HCC, the quantitative analysis of the HBP tumor enhancement in Gd-BOPTA-enhanced MRI (LLCER) accurately identifies moderately-poorly differentiated and/or MVI-positive HCCs. • After surgical resection for HCC, patients with LLCER - 4.72% or less had significantly poorer recurrence-free survival than patients with LLCER superior to - 4.72%. • Gd-BOPTA-enhanced MRI with delayed HBP images may be suggested as part of pre-surgery workup in patients with resectable HCC.

18F-FDG PET/CT predicts microvascular invasion and early recurrence after liver resection for hepatocellular carcinoma: A prospective observational study.

BACKGROUND: This study assessed the prognostic value of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) in the prediction of MVI and early recurrence following resection. METHOD: This prospective study (ClinicalTrials.gov ID: NCT02145013) included 78 consecutive HCC patients who underwent 18F-FDG PET/CT before curative-intent resection from 2014 to 2017. Prognostic factors available before surgery for predicting MVI and early recurrence (≤2 years) were identified by univariate and multivariate analyses. RESULTS: The 18F-FDG PET/CT result was positive in 30 (38%) patients. MVI was present in 33% (26/78) of specimens. Early recurrence occurred in 19% (14/74) of surviving patients. PET/CT positivity was the sole independent predictor of MVI (odds ratio [OR] = 3.6, 95% confidence interval [CI] = 1.1-11.2; p = 0.03), with a specificity and sensitivity for predicting MVI of 73% and 62%, respectively. Analysis of variables available before surgery showed that PET/CT positivity (hazard ratio [HR] = 5.8, 95% CI = 1.6-20.4; p = 0.006) and the male sex (HR = 6.6; 95% CI = 1.8-24.2; p = 0.005) were independent predictors of early recurrence. CONCLUSION: 18F-FDG PET/CT predicts MVI and early recurrence after surgery for HCC and could be used to select patients for neoadjuvant treatment.

Positron emission tomography/computed tomography with 18F-fluorocholine improve tumor staging and treatment allocation in patients with hepatocellular carcinoma.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) staging according to the Barcelona Clinical Liver Cancer (BCLC) classification is based on conventional imaging. The aim of our study was to assess the impact of dual-tracer 18F-fluorocholine and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) on tumor staging and treatment allocation. METHODS: A total of 192 dual-tracer PET/CT scans (18F-fluorocholine and 18F-fluorodeoxyglucose PET/CT) were performed in 177 patients with HCC. BCLC staging and treatment proposal were retrospectively collected based on conventional imaging, along with any new lesions detected, and changes in BCLC classification or treatment allocation based on dual-tracer PET/CT. RESULTS: Patients were primarily men (87.5%) with cirrhosis (71%) due to alcohol ±â€¯non-alcoholic steatohepatitis (26%), viral infection (62%) or unknown causes (12%). Among 122 patients with PET/CT performed for staging, BCLC stage based on conventional imaging was 0/A in 61 patients (50%), B in 32 patients (26%) and C in 29 patients (24%). Dual-tracer PET/CT detected new lesions in 26 patients (21%), upgraded BCLC staging in 14 (11%) and modified treatment strategy in 17 (14%). In addition, dual-tracer PET/CT modified the final treatment in 4/9 (44%) patients with unexplained elevation of alpha-fetoprotein (AFP), 10/25 patients (40%) with doubtful lesions on conventional imaging and 3/36 patients (8%) waiting for liver transplantation without active HCC after tumor response following bridging therapy. CONCLUSION: When used for HCC staging, dual-tracer PET/CT enabled BCLC upgrading and treatment modification in 11% and 14% of patients, respectively. Dual-tracer PET/CT might also be useful in specific situations (an unexplained rise in AFP, doubtful lesions or pre-transplant evaluation of patients without active HCC). LAY SUMMARY: Using a combination of tracers 18F-fluorocholine and 18F-fluorodeoxyglucose when performing positron emission tomography/computed tomography (PET/CT), often called a PET scan, helps to identify new tumor lesions in patients with hepatocellular carcinoma. This technique enabled staging modification of patients' tumors and led to changes in treatment allocation in certain patients.

Whole-Body Diffusion-weighted MR Imaging of Iron Deposits in Hodgkin, Follicular, and Diffuse Large B-Cell Lymphoma.

Purpose To analyze the frequency and distribution of low-signal-intensity regions (LSIRs) in lymphoma lesions and to compare these to fluorodeoxyglucose (FDG) uptake and biologic markers of inflammation. Materials and Methods The authors analyzed 61 untreated patients with a bulky lymphoma (at least one tumor mass ≥7 cm in diameter). When a LSIR within tumor lesions was detected on diffusion-weighted images obtained with a b value of 50 sec/mm2, a T2-weighted gradient-echo (GRE) sequence was performed and calcifications were searched for with computed tomography (CT). In two patients, Perls staining was performed on tissue samples from the LSIR. LSIRs were compared with biologic inflammatory parameters and baseline FDG positon emission tomography (PET)/CT parameters (maximum standardized uptake value [SUVmax], total metabolic tumor volume [TMTV]). Results LSIRs were detected in 22 patients and corresponded to signal void on GRE images; one LSIR was due to calcifications, and three LSIRS were due to a recent biopsy. In 18 patients, LSIRs appeared to be related to focal iron deposits; this was proven with Perls staining in two patients. The LSIRs presumed to be due to iron deposits were found mostly in patients with aggressive lymphoma (nine of 26 patients with Hodgkin lymphoma and eight of 20 patients with diffuse large B-cell lymphoma vs one of 15 patients with follicular lymphoma; P = .047) and with advanced stage disease (15 of 18 patients). LSIRS were observed in spleen (n = 14), liver (n = 3), and nodal (n = 8) lesions and corresponded to foci FDG uptake, with mean SUVmax of 9.8, 6.7, and 16.2, respectively. These patients had significantly higher serum levels of C-reactive protein, α1-globulin, and α2-globulin and more frequently had microcytic anemia than those without such deposits (P = .0072, P = .003, P = .0068, and P < .0001, respectively). They also had a significantly higher TMTV (P = .0055) and higher levels of spleen involvement (P < .0001). Conclusion LSIRs due to focal iron deposits are detected in lymphoma lesions and are associated with a more pronounced biologic inflammatory syndrome. © RSNA, 2017 Online supplemental material is available for this article.

Correction to: A rare presentation of skull-base osteomyelitis with neurovascular sheath extension following external otitis resolved by PET/MRI.

The figure in the original published version of this article was omitted.

Apical sparing pattern of left ventricular myocardial 99mTc-HMDP uptake in patients with transthyretin cardiac amyloidosis.

BACKGROUND: A decreased longitudinal strain in basal segments with a base-to-apex gradient has been described in patients with cardiac amyloidosis (CA). OBJECTIVES: Aim was to investigate the left ventricular (LV) regional distribution of early-phase 99mTc-Hydroxymethylene diphosphonate (99mTc-HMDP) uptake in patients with transthyretin-related cardiac amyloidosis (TTR-CA). METHODS: All patients underwent a whole-body planar 99mTc-HMDP scintigraphy acquired at 10-min post-injection (early-phase) followed by a thorax SPECT/CT. The segmental uptake (expressed as % of maximal myocardial HMDP uptake) was investigated on the AHA 17-segment model and 3-segment model (basal, mid-cavity, apical). RESULTS: Sixty-one TTR-CA patients were included of whom 29 were wild-type (wt-TTR-CA) and 32 had hereditary TTR-CA (m-TTR-CA). Early myocardial 99mTc-HMDP uptake occurred in all TTR-CA. In all patients, segmental analysis of the LV myocardial distribution of 99mTc-HMDP uptake showed an increased median uptake (interquartile range) in basal/mid-cavity segments compared to the lowest median uptake of apical segments (respectively, 79% [72%-86%] vs. 72% [64%-81%]; P < 10-6). This pattern was similar in wt-TTR-CA group (78% [70%-84%] vs. 70% [61%-81%]; P < 10-6), in m-TTR-CA group (80% [74%-86%] vs. 73 [66%-82%]; P < 10-7) and remained constant independently of the TTR mutation subtype with P ranging 10-5 to 0.03. CONCLUSIONS: Early-phase myocardial scintigraphy identified regional distribution of 99mTc-HMDP uptake characterized by a base-to-apex gradient, corroborating echocardiographic, and cardiac magnetic resonance findings. This apical sparing pattern was similar across TTR-CA and TTR mutation subtypes.

Early-phase myocardial uptake intensity of 99mTc-HMDP vs 99mTc-DPD in patients with hereditary transthyretin-related cardiac amyloidosis.

BACKGROUND: This study sought to compare the intensity of early-phase myocardial uptake of two phosphonate-based radiotracers, 99mTc-hydroxymethylene diphosphonate (HMDP) and 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD), in patients with hereditary transthyretin-related cardiac amyloidosis (TTR-CA). METHODS: Six patients with biopsy-proven diagnosis of TTR-CA and characteristic amyloid fibril composition underwent early-phase 99mTc-HMDP myocardial scintigraphy as part of their routine workup; they were later assessed by 99mTc-DPD scintigraphy after having signed informed written consent. Heart-to-mediastinum-ratio was measured at both time points as well as regional distribution on 17-segment analysis. RESULTS: All patients had an H/M ratio >1.28 on both imaging. 99mTc-DPD uptake was slightly higher than 99mTc-HMDP uptake in 3 patients, but no statistical difference was found (P = 0.13). Regional distribution of the two radiotracers was well correlated on bull's eyes analysis, with only slight underestimation of 99mTc-DPD uptake in the anterior/apical segments, compared with 99mTc-HMDP. CONCLUSION: 99mTc-HMDP and 99mTc-DPD show comparable myocardial uptake intensity on early-phase scintigraphy and can be used alternatively for the diagnosis of TTR-CA.