Contrast-enhanced ultrasound (CEUS) facilitated US in detecting lateral neck lymph node metastasis of thyroid cancer patients: diagnosis value and enhancement patterns of malignant lymph nodes

Objectives

To examine the value of CEUS as a non-invasive tool in detecting lateral neck metastasis (LNM) and the enhancement patterns of malignant lymph nodes (LN) for thyroid cancer patients.

Methods

Eighty-two consecutive patients, who underwent both preoperative non-enhanced US and CEUS examinations, were retrospectively reviewed. All patients underwent lateral neck dissection (LND). Enhancement patterns of 102 collected LNs matching to CEUS findings were analyzed.

Results

CEUS detected LNM in 53 of 65 patients, showing a higher sensitivity and accuracy than that of conventional US (p?=?0.109 and p?=?0.154, respectively). Thirteen patients’ surgical procedures were altered by CEUS findings, including nine true positive and four false positive cases. Five patients’ surgical procedures were altered by conventional US findings, including two true positive and three false positive cases. Heterogeneous enhancement, perfusion defects, microcalcification, and centripetal/hybrid enhancement were all specific criteria for malignant LNs in univariate analysis. In multivariate analysis, only heterogeneous enhancement and centripetal/hybrid enhancement were significantly related to LN metastasis (p?=?0.000 and p?=?0.037, respectively).

Conclusions

CEUS may be a potential tool to facilitate conventional US in detecting LNM. Heterogeneous enhancement and centripetal/hybrid enhancement are useful criteria to distinguish between malignant and benign LNs.

Key Points

? CEUS findings facilitated conventional US in detecting LNM. ? Heterogeneous, centripetal/hybrid enhancement, microcalcification and perfusion defects were specific criteria of malignant LNs. ? Heterogeneous and centripetal/hybrid enhancement were significantly related to LN metastasis in multivariate analysis.     

Effectiveness of contrast-enhanced ultrasound in the classification and emergency management of abdominal trauma

Objective

To analyse the correlation between contrast-enhanced ultrasound (CEUS)-based classification of the severity of abdominal parenchymal organ trauma and clinical outcomes, and to explore CEUS in classifying patients with such trauma, expecting that the use of CEUS will potentially enhance the quality and speed of the emergency management of abdominal trauma.

Methods

Three hundred six consecutive patients with blunt abdominal parenchymal organ trauma who received CEUS examination were retrospectively analysed. Two CEUS radiologists (identified as Reader A and Reader B in this study) who were not involved in the CEUS examinations of the patients were then asked to classify the patients independently according to their CEUS results. The classification results were later compared with patients’ clinical outcomes using Spearman’s rank correlation.

Results

The final clinical outcomes showed that 25.5 % (78/306) of patients received conservative treatment, 52.0 % (159/306) received minimally invasive treatment, and 22.5 % (69/306) received surgery. Spearman's rank correlation coefficients between the CEUS-based classification and clinical outcome were 0.952 from Reader A and 0.960 from Reader B.

Conclusions

CEUS can play an important role in the emergency management of abdominal trauma through the classification of patients for different treatment methods.

Key points

? The severity of abdominal trauma was classified by contrast-enhanced ultrasound (CEUS) ? There was a high correlation between CEUS-based classification and clinical outcomes ? CEUS-based classification is helpful for surgeons in the emergency management of abdominal trauma     

Utility of contrast-enhanced ultrasound with perflubutane for diagnosing the macroscopic type of small nodular hepatocellular carcinomas

Objective

To clarify the diagnostic value of contrast-enhanced ultrasound (CEUS) with perflubutane in the macroscopic classification of small nodular hepatocellular carcinomas (HCCs).

Methods

A total of 99 surgically resected nodular HCCs with a maximum diameter of 3 cm or less were analysed. HCCs were macroscopically categorized as simple nodular (SN) and non-SN. CEUS findings were evaluated during the arterial phase (vascularity, level and shape of enhancement), portal phase (presence or absence of washout) and post-vascular phase (echo intensity and shape).

Results

Sixty-eight HCCs were categorized as SN and the remaining 31 were categorized as non-SN. For diagnosis of non-SN HCC, the areas under the receiver operating characteristic curve (A _z) value for the shape of enhancement in the late arterial phase and the shape of the post-vascular image were 0.824 (95 % confidence interval [CI] 0.721–0.895) and 0.878 (95 % CI 0.788–0.933), respectively. The A _z value for the combination of the shape of enhancement in the late arterial phase and the shape of the post-vascular image for the diagnosis of non-SN HCC was 0.907 (95 % CI 0.815–0.956), corresponding to a high diagnostic value.

Conclusion

CEUS can provide high-quality imaging assessment for determining the macroscopic classification of small nodular HCCs.

Key points

? Non-SN is one of the poor prognostic factors in patients with HCC ? Assessment of macroscopic type provides valuable information for the management of HCC ? CEUS can provide high-quality imaging assessment for macroscopic classification of HCC ? For non-SN HCC diagnosed using CEUS, hepatectomy is preferred as curative treatment     

Contrast-enhanced ultrasound features of histologically proven focal nodular hyperplasia: diagnostic performance compared with contrast-enhanced CT

Objectives

To investigate and compare contrast-enhanced ultrasound (CEUS) in the characterisation of histologically proven focal nodular hyperplasia (FNH) with contrast-enhanced computed tomography (CECT).

Methods

CEUS was performed in 85 patients with 85 histologically proven FNHs. Enhancement, centrifugal filling, spoke-wheel arteries, feeding artery and central scarring were reviewed and correlated with lesion size or liver background. Independent factors for predicting FNH from other focal liver lesions (FLLs) were evaluated. Forty-seven FLLs with CECT were randomly selected for comparison of diagnostic performance with CEUS.

Results

Centrifugal filling was more common (P?=?0.002) and the significant predictor (P?=?0.003) in FNHs ≤3 cm. Lesion size or liver background has no significant influence on the detection rate of the spoke-wheel arteries and feeding artery (P?>?0.05). Central scarring was found in 42.6 % of FNHs ≥3 cm (P?=?0.000). The area under the ROC curve, sensitivity and specificity showed no significant differences between CEUS and CECT (P?>?0.05), except that the sensitivity of CEUS was better for reader 1 (P?=?0.041).

Conclusion

CEUS is valuable in characterising centrifugal filling signs or spoke wheels in small FNHs and should be employed as the first-line imaging technique for diagnosis of FNH.

Key Points

? The confident diagnosis of focal nodular hyperplasia is important in liver imaging. ? The centrifugal filling sign is useful for diagnosis of FNHs ≤3 cm. ? Contrast-enhanced ultrasound and contrast-enhanced CT have similar diagnostic performance for FNH. ? CEUS should be the first-line imaging technique for the diagnosis of FNH.     

Bone marrow oedema on MR imaging indicates ARCO stage 3 disease in patients with AVN of the femoral head

Objectives

To test the hypothesis that bone marrow oedema (BME) observed on MRI in patients with avascular necrosis (AVN) of the femoral head represents an indicator of subchondral fracture.

Methods

Thirty-seven symptomatic hips of 27 consecutive patients (53 % women, mean age 49.2) with AVN of the femoral head and associated BME on magnetic resonance (MR) imaging were included. MR findings were correlated with computed tomography (CT) of the hip and confirmed by histopathological examination of the resected femoral head. Imaging studies were analysed by two radiologists with use of the ARCO classification.

Results

On MR imaging a fracture line could be identified in 19/37 (51 %) cases, which were classified as ARCO stage 3 (n?=?15) and stage 4 (n?=?4). The remaining 18/37 (49 %) cases were classified as ARCO stage 2. However, in all 37/37 (100 %) cases a subchondral fracture was identified on CT, indicating ARCO stage 3/4 disease. The extent of subchondral fractures and the femoral head collapse was graded higher on CT as compared to MRI (P?Histopathological analysis confirmed bone necrosis and subchondral fractures.

Conclusions

In patients with AVN, BME of the femoral head represents a secondary sign of subchondral fracture and thus indicates ARCO stage 3 disease.

Key Points

? BME on MRI in AVN of femoral head indicates a subchondral fracture. ? BME in AVN of the femoral head represents ARCO stage 3/4 disease. ? CT identifies subchondral fractures and femoral head collapse better than MR imaging. ? This knowledge helps to avoid understaging and to trigger adequate treatment.     

Tumour volume doubling time of molecular breast cancer subtypes assessed by serial breast ultrasound

Objectives

The aim of our study was to evaluate the tumour volume doubling time (TVDT) of molecular breast cancer subtypes by serial ultrasound (US).

Methods

Sixty-six patients (mean age, 50 years; range, 29–78 years) with invasive breast cancer underwent initial and follow-up breast US examinations (at least three months apart) with no intervention. TVDT was determined using the tumours’ greatest dimensions in two orthogonal planes. The results were compared with clinical, imaging, and tumour variables and molecular subtypes (oestrogen receptor [ER]-positive, human epidermal growth factor receptor 2 [HER2]-positive, and triple negative) using a multiple linear regression analysis.

Results

TVDT exhibited a wide range (46–825 days; median, 141 days) with an overall mean of 193?±?141 days and mean values of 241?±?166 days for ER-positive tumours (n?=?37), 162?±?60 days for HER2-positive tumours (n?=?12), and 103?±?43 days for triple-negative tumours (n?=?17) (P?P?Conclusions TVDT differed significantly among the three molecular breast cancer subtypes, with the triple-negative tumours showing the fastest growth.

Key Points

? Knowledge of tumour volume doubling time provides clues for improving screening. ? TVDT assessed by serial US differed significantly between breast cancer subtypes. ? Triple-negative tumours had 2.4-fold shorter TVDT compared to ER-positive tumours. ? Tumours classified as BI-RADS 3 had shorter TVDT than BI-RADS 4.     

MR-sequences for prostate cancer diagnostics: validation based on the PI-RADS scoring system and targeted MR-guided in-bore biopsy

Purpose

This study evaluated the accuracy of MR sequences [T2-, diffusion-weighted, and dynamic contrast-enhanced (T2WI, DWI, and DCE) imaging] at 3T, based on the European Society of Urogenital Radiology (ESUR) scoring system [Prostate Imaging Reporting and Data System (PI-RADS)] using MR-guided in-bore prostate biopsies as reference standard.

Methods

In 235 consecutive patients [aged 65.7?±?7.9 years; median prostate-specific antigen (PSA) 8 ng/ml] with multiparametric prostate MRI (mp-MRI), 566 lesions were scored according to PI-RADS. Histology of all lesions was obtained by targeted MR-guided in-bore biopsy.

Results

In 200 lesions, biopsy revealed prostate cancer (PCa). The area under the curve (AUC) for cancer detection was 0.70 (T2WI), 0.80 (DWI), and 0.74 (DCE). A combination of T2WI + DWI, T2WI + DCE, and DWI + DCE achieved an AUC of 0.81, 0.78, and 0.79. A summed PI-RADS score of T2WI + DWI + DCE achieved an AUC of 0.81. For higher grade PCa (primary Gleason pattern?≥?4), the AUC was 0.85 for T2WI + DWI, 0.84 for T2WI + DCE, 0.86 for DWI + DCE, and 0.87 for T2WI + DWI + DCE. The AUC for T2WI + DWI + DCE for transitional-zone PCa was 0.73, and for the peripheral zone 0.88. Regarding higher-grade PCa, AUC for transitional-zone PCa was 0.88, and for peripheral zone 0.96.

Conclusion

The combination of T2WI + DWI + DCE achieved the highest test accuracy, especially in patients with higher-grade PCa. The use of ≤2 MR sequences led to lower AUC in higher-grade and peripheral-zone cancers.

Key Points

? T2WI + DWI + DCE achieved the highest accuracy in patients with higher grade PCa ? T2WI + DWI + DCE was more accurate for peripheral- than for transitional-zone PCa ? DCE increased PCa detection accuracy in the peripheral zone ? DWI was the leading sequence in the transitional zone     

A high-resolution computed tomography-based scoring system to differentiate the most infectious active pulmonary tuberculosis from community-acquired pneumonia in elderly and non-elderly patients

Objective

The objective of this study was to use high-resolution computed tomography (HRCT) imaging to predict the presence of smear-positive active pulmonary tuberculosis (PTB) in elderly (at least 65 years of age) and non-elderly patients (18–65 years of age).

Methods

Patients with active pulmonary infections seen from November 2010 through December 2011 received HRCT chest imaging, sputum smears for acid-fast bacilli and sputum cultures for Mycobacterium tuberculosis. Smear-positive PTB was defined as at least one positive sputum smear and a positive culture for M. tuberculosis. Multivariate logistic regression analyses were performed to determine the HRCT predictors of smear-positive active PTB, and a prediction score was developed on the basis of receiver operating characteristic curve analysis.

Results

Of 1,255 patients included, 139 were diagnosed with smear-positive active PTB. According to ROC curve analysis, the sensitivity, specificity, positive predictive value, negative predictive value, false positive rates and false negative rates were 98.6 %, 95.8 %, 78.5 %, 99.8 %, 4.2 % and 1.4 %, respectively, for diagnosing smear-positive active PTB in elderly patients, and 100.0 %, 96.9 %, 76.5 %, 100.0 %, 3.1 % and 0.0 %, respectively, for non-elderly patients.

Conclusions

HRCT can assist in the early diagnosis of the most infectious active PTB, thereby preventing transmission and minimizing unnecessary immediate respiratory isolation.

Key Points

? HRCT can assist in the early diagnosis of the infectious active PTB ? HRCT imaging is useful to predict the presence of smear-positive active PTB ? Predictions from the HRCT imaging are valid even before sputum smear or culture results     

Vasogenic edema characterizes pediatric acute disseminated encephalomyelitis

Introduction

MR imaging criteria for diagnosing acute disseminated encephalomyelitis (ADEM) have not been clearly established. Due to the wide spectrum of differential considerations, new imaging features allowing early and accurate diagnosis for ADEM are needed. We hypothesized that ADEM lesions would be characterized by vasogenic edema due to the potential reversibility of the disease.

Methods

Sixteen patients who met the diagnostic criteria for ADEM proposed by the International Pediatric Multiple Sclerosis Study Group (IPMSSG) and had complete MR imaging studies performed at our institution during the acute phase of the disease were identified retrospectively and evaluated by experienced pediatric neuroradiologists.

Results

Vasogenic edema was demonstrated on diffusion-weighted imaging (DWI) and corresponding apparent diffusion coefficient (ADC) maps in 12 out of 16 patients; cytotoxic edema was identified in two patients while the other two patients displayed no changes on DWI/ADC. ADC values for lesions and normal-appearing brain tissue were 1.39?±?0.45?×?10^?3 and 0.81?±?0.09?×?10^?3 mm/s², respectively (p?=?0.002). When considering a cutoff of 5 days between acute and subacute disease, no difference between ADC values in acute vs. subacute phase was depicted. However, we found a significant correlation and an inverse and significant relationship between time and ADC value.

Conclusion

We propose that vasogenic edema is a reliable diagnostic sign of acute neuroinflammation in ADEM.     

99mTc-MAA overestimates the absorbed dose to the lungs in radioembolization: a quantitative evaluation in patients treated with 166Ho-microspheres

Purpose

Radiation pneumonitis is a rare but serious complication of radioembolic therapy of liver tumours. Estimation of the mean absorbed dose to the lungs based on pretreatment diagnostic ^99mTc-macroaggregated albumin (^99mTc-MAA) imaging should prevent this, with administered activities adjusted accordingly. The accuracy of ^99mTc-MAA-based lung absorbed dose estimates was evaluated and compared to absorbed dose estimates based on pretreatment diagnostic ¹⁶⁶Ho-microsphere imaging and to the actual lung absorbed doses after ¹⁶⁶Ho radioembolization.

Methods

This prospective clinical study included 14 patients with chemorefractory, unresectable liver metastases treated with ¹⁶⁶Ho radioembolization. ^99mTc-MAA-based and ¹⁶⁶Ho-microsphere-based estimation of lung absorbed doses was performed on pretreatment diagnostic planar scintigraphic and SPECT/CT images. The clinical analysis was preceded by an anthropomorphic torso phantom study with simulated lung shunt fractions of 0 to 30 % to determine the accuracy of the image-based lung absorbed dose estimates after ¹⁶⁶Ho radioembolization.

Results

In the phantom study, ¹⁶⁶Ho SPECT/CT-based lung absorbed dose estimates were more accurate (absolute error range 0.1 to ?4.4 Gy) than ¹⁶⁶Ho planar scintigraphy-based lung absorbed dose estimates (absolute error range 9.5 to 12.1 Gy). Clinically, the actual median lung absorbed dose was 0.02 Gy (range 0.0 to 0.7 Gy) based on posttreatment ¹⁶⁶Ho-microsphere SPECT/CT imaging. Lung absorbed doses estimated on the basis of pretreatment diagnostic ¹⁶⁶Ho-microsphere SPECT/CT imaging (median 0.02 Gy, range 0.0 to 0.4 Gy) were significantly better predictors of the actual lung absorbed doses than doses estimated on the basis of ¹⁶⁶Ho-microsphere planar scintigraphy (median 10.4 Gy, range 4.0 to 17.3 Gy; p?99mTc-MAA SPECT/CT imaging (median 2.5 Gy, range 1.2 to 12.3 Gy; p?99mTc-MAA planar scintigraphy (median 5.5 Gy, range 2.3 to 18.2 Gy; p?Conclusion In clinical practice, lung absorbed doses are significantly overestimated by pretreatment diagnostic ^99mTc-MAA imaging. Pretreatment diagnostic ¹⁶⁶Ho-microsphere SPECT/CT imaging accurately predicts lung absorbed doses after ¹⁶⁶Ho radioembolization.     

Imaging findings of hepatic focal nodular hyperplasia in men and women: are they really different?

Purpose

This study was undertaken to compare the imaging findings of focal nodular hyperplasia (FNH) in men and women, as seen on multidetector computed tomography (MDCT), magnetic resonance imaging (MRI) and contrast-enhanced ultrasound (CEUS).

Materials and methods

Two radiologists reviewed 195 imaging studies (17 MDCT, 81 MRI and 97 CEUS examinations) pertaining to 111 FNHs (mean size 3 cm) in 91 patients (mean age 39 years). For each lesion, the readers assessed size, location, echogenicity, attenuation, or signal intensity in comparison with adjacent liver parenchyma on both unenhanced and postcontrast images.

Results

Eighty-nine FNHs (mean size 3.1 cm) were observed in 73 women (mean age 37.9 years) and 22 FNHs (mean size 2.7 cm) in 18 men (mean age 41.2 years). No statistically significant differences were found between men and women in terms of age, FNH lesions per patient (1.22 and 1.21, respectively), size, baseline and enhancement pattern on MRI, CEUS and MDCT (p < 0.05). A central scar in FNHs was depicted in 4/18 (22.2 %) men and 16/63 (25.4 %) women on MRI (p < 0.05), and in 1/2 (50 %) men and 7/15 (46.7 %) women on MDCT (p < 0.05), whereas a spoke-wheel pattern, central scar, and/or feeding vessel were seen in 5/17 (29.4 %) men and 22/80 (27.5 %) women on CEUS (p < 0.05).

Conclusions

Our results did not show any differences in imaging features, age of occurrence and size of FNH between men and women.     

The combination of FDG PET and dynamic contrast-enhanced MRI improves the prediction of disease-free survival in patients with advanced breast cancer after the first cycle of neoadjuvant chemotherapy

Purpose

The aim of this study was to investigate the potential of FDG PET/CT and MRI in predicting disease-free survival (DFS) after neoadjuvant chemotherapy (NAC) and surgery in patients with advanced breast cancer.

Methods

The analysis included 54 women with advanced breast cancer. All patients received three cycles of NAC, underwent curative surgery, and then received three cycles of additional chemotherapy. Before and after the first cycle of NAC, all patients underwent sequential PET/CT and MRI. All patients were analysed using a diverse range of parameters. including maximal standardized uptake value (SUV), percent change in SUV (ΔSUV), initial slope of the enhancement curve (MRslope), apparent diffusion coefficient (ADC), tumour size, change in MRslope (ΔMRslope), change in ADC (ΔADC), change in tumour size (Δsize) and other clinicopathological parameters]. The relationships between covariates and DFS after surgery were analysed using the Kaplan-Meier method and the multivariate Cox proportional hazards model. Time-dependent receiver operating characteristic curves were used to determine the optimal cut-off values of imaging parameters for DFS.

Results

Of the 54 patients, 13 (24 %) experienced recurrence at a median follow-up of 38 months (range 25 – 45 months). Univariate and multivariate analyses showed that a lesser decline in SUV, a lesser decline in MRslope, a lesser increase in ADC, and ER negativity were significantly associated with a poorer DFS (P?=?0.0006, ΔSUV threshold ?41 %; P?=?0.0016, ΔMRslope threshold ?6 %; P?=?0.011, ΔADC threshold 11 %; and P?=?0.0086, ER status, respectively). Patients with a combination of ΔSUV >?41 % and ΔMRslope >?6 % showed a significantly higher recurrence rate (77.8 %) than the remaining of patients (13.3 %, P?Conclusion Functional parameters of both FDG PET and MRI after the first cycle of NAC are useful for predicting DFS in patients with advanced breast cancer. This approach could lead to an improvement in patient care because ineffective NAC agents could be avoided and more aggressive therapy could be used in high-risk patients.     

Value of 18F-FDG uptake on PET/CT and CEA level to predict epidermal growth factor receptor mutations in pulmonary adenocarcinoma

Purpose

The identification of the mutation status of the epidermal growth factor receptor (EGFR) is important for the optimization of treatment in patients with pulmonary adenocarcinoma. The acquisition of adequate tissues for EGFR mutational analysis is sometimes not feasible, especially in advanced-stage patients. The aim of this study was to predict EGFR mutation status in patients with pulmonary adenocarcinoma based on ¹⁸F-fluorodeoxyglucose (FDG) uptake and imaging features in positron emission tomography/computed tomography (PET/CT), as well as on the serum carcinoembryonic antigen (CEA) level.

Methods

We retrospectively reviewed 132 pulmonary adenocarcinoma patients who underwent EGFR mutation testing, pretreatment FDG PET/CT and serum CEA analysis. The associations between EGFR mutations and patient characteristics, maximal standard uptake value (SUVmax) of primary tumors, serum CEA level and CT imaging features were analyzed. Receiver-operating characteristic (ROC) curve analysis was performed to quantify the predictive value of these factors.

Results

EGFR mutations were identified in 69 patients (52.2 %). Patients with SUVmax ≥6 (p?=?0.002) and CEA level ≥5 (p?=?0.013) were more likely to have EGFR mutations. The CT characteristics of larger tumors (≥3 cm) (p?=?0.023) and tumors with a nonspiculated margin (p?=?0.026) were also associated with EGFR mutations. Multivariate analysis showed that higher SUVmax and CEA level, never smoking and a nonspiculated tumor margin were the most significant predictors of EGFR mutation. The combined use of these four criteria yielded a higher area under the ROC curve (0.82), suggesting a good discrimination.

Conclusion

The combined evaluation of FDG uptake, CEA level, smoking status and tumor margins may be helpful in predicting EGFR mutation status in patients with pulmonary adenocarcinoma, especially when the tumor sample is inadequate for genetic analysis or genetic testing is not available. Further large-scale prospective studies are needed to validate these results.     

Relationship of decreased accumulation of 99mTc-tetrofosmin on myocardial single-photon emission computed tomography images between QRS duration in dilated cardiomyopathy patient with left bundle branch block

Purpose

This study aimed to clarify the relationship between severity of conduction delay in the left ventricle and myocardial uptake of ^99mTc-tetrofosmin (TF) in dilated cardiomyopathy (DCM) patients with left bundle branch block (LBBB).

Methods and Results

Thirty-two DCM patients with LBBB underwent electrocardiography and ^99mTc-TF myocardial single-photon emission computed tomography (SPECT). SPECT images were acquired at 30 min (early images) and 3 h (late images) after injection. We calculated the total defect score (TDS) using a 20-segment model with a 5-point scoring system. The TDS in early and late images was defined as the summed early score (SES) and summed late score (SLS), respectively. On early images, 29 of 32 patients (91%) had decreased tracer uptake in the septum. All patients showed a decreased tracer uptake in the septum on late images. A significant correlation was observed between TDS (both SES and SLS) and QRS duration, with SLS showing an excellent correlation (SES: r = 0.554, P < 0.001; SLS: r = 0.779, P < 0.0001).

Conclusions

These findings suggest that in DCM patients with LBBB, hypoperfusion and myocardial damage in the septum might occur in accordance with an increase in the QRS duration.     

Prognostic Value of Metabolic Tumor Volume Estimated by 18 F-FDG Positron Emission Tomography/Computed Tomography in Patients with Diffuse Large B-Cell Lymphoma of Stage II or III Disease

Purpose

The purpose of this study was to evaluate the prognostic value of metabolic tumor volume (MTV) measured by ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT) in patients with diffuse large B-cell lymphoma (DLBCL) treated with rituximab-containing immunochemotherapy.

Methods

Patients with newly diagnosed DLBCL who underwent pre-treatment torso FDG-PET/CT scan taken within 10 days before treatment were included. MTV was defined as the volume of hypermetabolic tissue with a standardized uptake value (SUV) greater than a threshold value of 2.5 and calculated using volume viewer software. Association of MTV with patient characteristics and survival were compared.

Results

A total of 96 patients were evaluated. During a median follow-up period of 27.8 months, 3-year event-free survival (EFS) and overall survival was 69.5 % and 72.9 %, respectively. The Ann Arbor staging showed a limitation of prognosis because there was no difference of EFS between patients with Ann Arbor stage II and those with stage III. On the contrary, among patients with Ann Arbor stage II or III disease (n?=?53), the higher MTV group showed significantly inferior EFS compared with the lower MTV group.

Conclusions

In the current study, we identified the pre-treatment MTV measured by FDG-PET/CT as a potential predictor of survival in patients with DLBCL treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP), at least in Ann Arbor stage II and III disease.     

Diagnostic value of FDG-PET/(CT) in children with fever of unknown origin and unexplained fever during immune suppression

Purpose

Fever of unknown origin (FUO) and unexplained fever during immune suppression in children are challenging medical problems. The aim of this study is to investigate the diagnostic value of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and FDG-PET combined with computed tomography (FDG-PET/CT) in children with FUO and in children with unexplained fever during immune suppression.

Methods

All FDG-PET/(CT) scans performed in the Radboud university medical center for the evaluation of FUO or unexplained fever during immune suppression in the last 10 years were reviewed. Results were compared with the final clinical diagnosis.

Results

FDG-PET/(CT) scans were performed in 31 children with FUO. A final diagnosis was established in 16 cases (52 %). Of the total number of scans, 32 % were clinically helpful. The sensitivity and specificity of FDG-PET/CT in these patients was 80 % and 78 %, respectively. FDG-PET/(CT) scans were performed in 12 children with unexplained fever during immune suppression. A final diagnosis was established in nine patients (75 %). Of the total number of these scans, 58 % were clinically helpful. The sensitivity and specificity of FDG-PET/CT in children with unexplained fever during immune suppression was 78 % and 67 %, respectively.

Conclusions

FDG-PET/CT appears a valuable imaging technique in the evaluation of children with FUO and in the diagnostic process of children with unexplained fever during immune suppression. Prospective studies of FDG-PET/CT as part of a structured diagnostic protocol are warranted to assess the additional diagnostic value.     

Correlation between 18F-fluoromisonidazole PET and expression of HIF-1α and VEGF in newly diagnosed and recurrent malignant gliomas

Purpose

Hypoxia and its consequences at the molecular level promote tumour progression and affect patient prognosis. One of the main early cellular events evoked by hypoxia is induction of hypoxia-inducible factor 1 (HIF-1) and subsequent upregulation of vascular endothelial growth factor (VEGF). In this study we sought to determine whether hypoxia detected by ¹⁸F-fluoromisonidazole (FMISO) PET accurately reflects the expression of HIF-1α and VEGF in the tumour and can be used as a biomarker of antiangiogenic treatment and as a prognostic factor in newly diagnosed and recurrent malignant gliomas.

Methods

Enrolled in this study were 32 patients with newly diagnosed glioma and 16 with recurrent glioma of grade III or grade IV. All the patients had undergone FMISO PET preoperatively. The maximum tumour-to-blood FMISO activity ratio (T/B_max) was used to evaluate the degree of tumour hypoxia and the hypoxic volume (HV) was calculated using a tumour-to-blood FMISO uptake ratio of ≥1.2. Immunohistochemical expressions of HIF-1α and VEGF were evaluated semiquantitatively using the immunoreactivity score (IRS, scores 0 to 12) and the correlation was examined between IRS of HIF-1α or VEGF and FMISO uptake of the tumour (SUV_tumour) using navigation-based sampling. Survival was estimated using the Kaplan-Meier method in relation to the T/B_max and the HV.

Results

The T/B_max and the HV in grade IV gliomas were significantly higher than in grade III gliomas (P?P?VEGF expression was observed in the majority of malignant gliomas. The IRS of HIF-1α and VEGF in the tumour were not significantly different between grade III and grade IV gliomas. The IRS of HIF-1α in the tumour did not correlate with the SUV_tumour of FMISO in either newly diagnosed or recurrent glioma. There was a significant but weak correlation between the IRS of VEGF and the SUV_tumour of FMISO in newly diagnosed glioma, but not in recurrent glioma. The overall survival time in patients with a small HV and a low FMISO T/B_max was significantly longer than in those with a large HV and a high FMISO T/B_max (P?P?Conclusion Preoperative FMISO uptake is significantly correlated with the expression of VEGF in the tumour and might be used as a biomarker of antiangiogenic treatment in newly diagnosed malignant gliomas. However, caution is required because the correlation was weak and there was a large overlap of FMISO uptake between glioma with high and low VEGF expression. In addition, hypoxia determined by FMISO PET appears to be a suitable biomarker for predicting a highly malignant tumour and a poor prognosis in patients with malignant glioma.     

Is the type and extent of hippocampal sclerosis measurable on high-resolution MRI?

Introduction

The purpose of this study is to relate hippocampal volume and FLAIR signal intensity to Wyler grading of hippocampal sclerosis (HS).

Methods

Of 100 consecutive patients with temporal lobe epilepsy and HS as histopathological diagnosis, 32 had high-resolution 3 Tesla MRI and anatomically well-preserved hippocampi following amygdalo-hippocampectomy. Hippocampal volume on 3D T1-weighted gradient echo and signal intensity on coronal FLAIR sequences were determined using FreeSurfer and SPM tools and related to Wyler grading. Seizure outcome was determined after 1 year.

Results

Histopathology showed four Wyler II, 19 Wyler III, and 9 Wyler IV HS. Hippocampal volumes were 3.08 ml for Wyler II (Wyler II/contralateral side: p?>?0.05), 2.19 ml for Wyler III (p?p?=?0.01), and 3.08 ml for the contralateral side. Normalized FLAIR signals were 1,354 (p?=?0.0004), 1,408 (p?p?Conclusions Combined volumetry and quantitative FLAIR signal analysis clearly identifies Wyler III and IV HS. Quantitative FLAIR signal analysis may be helpful to identify Wyler II HS.     

68Ga-DOTATATE PET/CT in the evaluation of patients with neuroendocrine metastatic carcinoma of unknown origin

Objective

There is little evidence regarding the role of ⁶⁸Ga-DOTATATE PET/CT for the identification of primary tumors in patients with metastatic neuroendocrine carcinoma of unknown primary. The aim of this study is to assess the value of this technique in the mentioned clinical scenario.

Methods

We retrospectively studied twenty-nine patients (mean age 59.5 ± 10.6 years; female 17) with pathologically proven neuroendocrine metastases. In all cases conventional imaging was negative for primary tumor identification. ⁶⁸Ga-DOTATATE PET/CT was performed with a mean dose of 104.2 ± 18.8 MBq, using a 64-slice PET/CT with time-of-flight correction. A team of an experienced radiologist and a nuclear medicine physician evaluated the images. The maximum SUV (SUVm) was measured in all abnormal foci. Histopathology (when available) and/or clinical follow-up with correlative imaging was considered as reference standard.

Results

⁶⁸Ga-DOTATATE PET/CT identified the primary tumor in 17/29 (59 %) patients in the following locations: pancreas (n = 7), ileum (n = 7), duodenum (n = 1), colon (n = 1) and stomach (n = 1). In this population a significant correlation was found between SUVm of primary tumor and metastases (r = 0.815, P < 0.0001). Furthermore, additional sites of unsuspected metastases were demonstrated in 9 patients of this group and in 6 patients in whom no primary tumor was localized, mainly in lymph nodes and mesentery. Pathology confirmation was obtained in 7 patients who underwent surgery, whereas in the remaining 10 patients, correlative imaging and follow-up confirmed primary tumor localization.

Conclusions

⁶⁸Ga-DOTATATE PET/CT is a clinically useful imaging technique for the localization of primary tumors in patients with neuroendocrine metastatic carcinoma of unknown origin with the potential of having a significant impact in patient management and therapy planning.