Lorenzo Bacigalupo

Value of Fused 18F-Choline-PET/MRI to Evaluate Prostate Cancer Relapse in Patients Showing Biochemical Recurrence after EBRT: Preliminary Results

Purpose. We compared the accuracy of 18F-Choline-PET/MRI with that of multiparametric MRI (mMRI), 18F-Choline-PET/CT, 18F-Fluoride-PET/CT, and contrast-enhanced CT (CeCT) in detecting relapse in patients with suspected relapse of prostate cancer (PC) after external beam radiotherapy (EBRT). We assessed the association between standard uptake value (SUV) and apparent diffusion coefficient (ADC). Methods. We evaluated 21 patients with biochemical relapse after EBRT. Patients underwent 18F-Choline-PET/contrast-enhanced (Ce)CT, 18F-Fluoride-PET/CT, and mMRI. Imaging coregistration of PET and mMRI was performed. Results. 18F-Choline-PET/MRI was positive in 18/21 patients, with a detection rate (DR) of 86%. DRs of 18F-Choline-PET/CT, CeCT, and mMRI were 76%, 43%, and 81%, respectively. In terms of DR the only significant difference was between 18F-Choline-PET/MRI and CeCT. On lesion-based analysis, the accuracy of 18F-Choline-PET/MRI, 18F-Choline-PET/CT, CeCT, and mMRI was 99%, 95%, 70%, and 85%, respectively. Accuracy, sensitivity, and NPV of 18F-Choline-PET/MRI were significantly higher than those of both mMRI and CeCT. On whole-body assessment of bone metastases, the sensitivity of 18F-Choline-PET/CT and 18F-Fluoride-PET/CT was significantly higher than that of CeCT. Regarding local and lymph node relapse, we found a significant inverse correlation between ADC and SUV-max. Conclusion. 18F-Choline-PET/MRI is a promising technique in detecting PC relapse.

Crohn's disease: prevalence of intestinal and extraintestinal manifestations detected by computed tomography enterography with water enema.

BackgroundComputed tomography enterography (CTE) may detect the presence, severity, and extent of bowel inflammation in patients with Crohn’s disease (CD). The aim of our study was to assess, among a cohort of 22 histologically proven CD patients, the prevalence of disease distribution, behavior, anastomotic recurrence and extraintestinal manifestations detected by an original CTE technique.MethodsTwo radiologists reviewed 221 CTEs performed providing both small and large bowel distension by oral administration of neutral contrast material and trans-rectal introduction of a water enema (CTE-WE).ResultsIleal CD was detected in 116 CTE-WEs (52.4%), including 71/116 (61.2%) non-stricturing/non-penetrating, 17/116 (14.6%) stricturing, and 28/116 (24.1%) penetrating forms. Colonic CD was appreciable in 35 (15.8%) patients, including 18/35 (51.4%) non-stricturing/non-penetrating, 6/35 (17.1%) stricturing, and 11/35 (31.4%) penetrating forms. Ileocolic CD was present in 52 (23.5%) CTE-WEs, including 30/52 (57.7%) non-stricturing/ non-penetrating; 3/52 (5.7%) stricturing, and 19/52 (36.5%) penetrating forms. In 10/221 patients (4.5%), upper gastrointestinal involvement (UGI) was present. Perianal disease was observed in 17/221 patients (7.7%). Fistulas were present in 52 (23.5%) and abscesses in 24 (10.8%) CTE-WEs, respectively. Among 57/221 (25.8%) patients who had undergone a disease-related intestinal resection, in 30/57 cases (52.6%) CD recurrence at the anastomosis was present. 4/221 patients (1.8%) with a histologically confirmed intestinal neoplastic stenosis were observed. Sacroiliitis (24%) was found to be prevalent over hepatic steatosis (10.8%), cholelithiasis (8.6%), and nephrolithiasis (4%).ConclusionsCTE-WE represents a comprehensive imaging technique which may demonstrate bowel inflammation and CD extraintestinal manifestations. A peculiar prevalence of UGI involvement and neoplastic strictures were observed. In our study the prevalence of sacroiliitis resulted higher than previously reported.

What is the sensitivity of mammography and dynamic MR imaging for DCIS if the whole-breast histopathology is used as a reference standard?

Purpose. Our purpose was to compare mammography and dynamic contrast-enhanced magnetic resonance imaging (MRI) in the detection of ductal carcinoma in situ (DCIS)Materials and methods. Ninety patients (aged 58.6±16.1 years) who were candidates for unilateral (n=81) or bilateral (n=9) mastectomy underwent mammography and dynamic contrast-enhanced breast MRI using a coronal three-dimensional gradient-echo sequence with slice thickness ≤3 mm before and after intravenous injection of gadoteridol (0.1 mmol/kg). Mammographic and MR images were evaluated by two offsite readers working in consensus. Pathological examination performed on 5-mm sections covering the whole breast was used as a reference standardResults. Out of 99 breasts, pathology revealed 26 DCIS in 14 breasts of 14 patients, aged 52.0+_9.6 years. Lesion diameter at pathology was <5 mm (n=4); ≥5 and <10 mm (n=7); ≥10 and <20 mm (n=3); ≥20 mm (n=2); not assessed (n=10). Sensitivity was 35% (9/26) for mammography and 38% (10/26) for MRI (not significant difference, McNemar test). Both mammography and MRI provided a true positive result in seven cases (four of them measured at pathology, with a diameter of 20.0±12.9 mm; median 20 mm) and a false negative result in 14 cases (10 of them measured at pathology, with a diameter of 4.2±1.9 mm; median 4.6 mm) (p=0.024, Mann-Whitney U test). Only 46% (12/26) of DCIS were detected at mammography and/or MRI; the remaining 54% (14/26) were diagnosed only at pathological examinationConclusions. When the whole breast is used as the histopathological reference standard, both mammography and MRI show low sensitivity for DCISRiassuntoObiettivo . Confrontare la sensibilità per il carcinoma duttale in situ (DCIS) della mammografia e della risonanza magnetica (RM) con mezzo di contrastoMateriali e metodi . Novanta pazienti (età 58.6±16.1 anni) candidate alla mastectomia monolaterale (n=81) o bilaterale (n=9) sono state sottoposte a mammografia e RM a contrasto dinamico mediante sequenza tridimensionale coronale gradient-echo con spessore di strato ≤3 mm, prima e dopo iniezione endovenosa di gadoteridolo (0.1 mmol/kg). Mammografia e RM sono state valutate da due lettori off-site, in consenso. L’;esame istologico dell’;intera mammella (strati di 5 mm di spessore) ha rappresentato lo standard di riferimentoRisultati . L’esame istologico delle 99 mammelle ha evidenziato 26 DCIS in 14 mammelle di 14 pazienti (età 52.0±9.6 anni). All’esame istologico il diametro della lesione è risultato <5 mm (n=4); ≥5 e <10 mm (n=7); ≥10 e <20 mm (n=3); ≥20 mm (n=2); non valutato (n=10). La sensibilità è risultata del 35% (9/26) per la mammografia e del 38% (10/26) per la RM (differenza non significativa, test di McNemar). Mammografia e RM sono risultate entrambe vere positive in 7 casi (4 dei quali con diametro misurato istologicamente, pari a 20.0±12.9 mm, mediana 20 mm) ed entrambe false negative in 14 casi (10 dei quali con diametro misurato istologicamente, pari a 4.2±1.9 mm, mediana 4.6) (p=0.024, test U di Mann-Whitney). Solo il 46% (12/26) dei DCIS sono stati identificati alla mammografia e/o alla RM mentre il rimanente 54% (14/26) è stato riconosciuto solo all’esame istologicoConclusioni . Allorquando l’intera mammella è assunta come standard di riferimento istologico, sia la mammografia che la RM mostrano ridotta sensibilità per il DCIS

Diagnostic value of real-time elastography in the assessment of hepatic fibrosis in patients with liver iron overload

OBJECTIVE The objective of our prospective monocentric work was to determine the diagnostic value of real-time elastography (RTE) in the assessment of liver fibrosis in patients with iron overload, using transient elastography (TE) as reference standard. METHODS Sixty-seven consecutive patients with MRI detectable iron overload (T2*<6.3 ms) were enrolled. TE and RTE were performed on the same day as MRI. Elastograms were acquired by an experienced operator and analyzed by calculating the elastic ratio between perihepatic soft tissues and liver parenchyma. An elliptical ROI of 1cm(2) (Z1) was positioned in the liver parenchyma and a smaller elliptical ROI of 2mm(2) (Z2) was positioned in a homogeneously soft (red) region of the diaphragm, which was considered as internal control to calculate the elastic ratio Z2/Z1. RESULTS Seven patients were excluded because of invalid TE or RTE examinations. The remaining 60 patients were 57% males and 43% females (mean age: 42 [21-76] years), including 37 homozygous-β-thalassemics, 13 patients with β-thalassemia intermedia, 6 with primary hemochromatosis, and 4 with myelodysplastic syndrome. Increasing elastic ratios were significantly correlated with increasing TE values (r=0.645, 95% CI 0.468-0.772, P<0.0001). The mean elastic ratios for each METAVIR group were as follows: F0/1 = 1.9 ± 0.4; F2 = 2.2 ± 0.4; F3 = 2.9 ± 0.5; F4 = 3.2 ± 0.4. The diagnostic accuracy of RTE for F ≥ 2 evaluated by AUC-ROC analysis was 0.798 (95% CI 0.674-0.890). The diagnostic accuracy of RTE for F ≥ 3 was 0.909 (95% CI 0.806-0.968). At a cut-off ≥ 2.75, RTE showed a sensitivity of 70% (95% CI 45.7-88.1) and a specificity of 97.5% (95% CI 86.8-99.9). CONCLUSIONS In patients with MRI-detectable liver iron-overload RTE allows to discriminate between F0/1-F2 and F3-F4 with a reasonable diagnostic accuracy.

Musculoskeletal Manifestations of Chronic Anemias

This article provides an overview of the current use of diagnostic imaging modalities in the evaluation of a heterogeneous group of disorders causing chronic anemias by impaired blood cell production (inherited bone marrow failure syndromes of childhood, aplastic anemia and myelodysplastic syndromes, β-thalassemia) or increased blood cell destruction (sickle cell disease). During the course of these disorders, various musculoskeletal abnormalities can be encountered, including marrow hyperplasia, reversion of yellow marrow to red marrow, growth disturbances, and, occasionally, extramedullary hematopoiesis. Diagnostic imaging may help the clinician to identify specific complications related to either the disease (e.g., bone infarction and acute osteomyelitis in sickle cell disease) or transfusion (e.g., iron overload due to increased hemolysis) and iron chelation (e.g., desferrioxamine-related dysplastic bone changes and deferiprone-related degenerative arthritis) treatments. In this field, magnetic resonance imaging plays a pivotal role because of its high tissue contrast that enables early assessment of bone marrow changes before they become apparent on plain films or computed tomography or metabolic changes occur on bone scintigraphy or positron emission tomography scan. Overall, familiarity with the range of radiological appearances in chronic anemias is important to diagnose complications and establish appropriate therapy.

Computed Tomography Colonography in Acromegaly

INTRODUCTION AND AIM Acromegalic patients have an increased risk for the development of colorectal cancer. For this reason, since 1996, screening colonoscopy has been recommended in all patients with acromegaly. The aim of our study was to assess the feasibility and to evaluate the results of computed tomography (CT)-colonography in acromegaly. PATIENTS AND METHODS We examined 23 acromegalic patients with no history of colorectal cancer (11 females and 12 males; age range 18-79 yr; disease duration range 1-15 yr) with CT-colonography. Twenty of them underwent traditional colonoscopy after the CT-colonography. RESULTS CT-colonography examination results were adequate in 17 of 23 cases (73%). CT-colonography found 12 polyps in eight patients, 95% confirmed by traditional colonoscopy. One polyp was a sigmoid cancer, and the diagnosis was confirmed at surgery. There were no polyps found by traditional colonoscopy that CT-colonography was not able to identify. The lesions were located in right colon (two), transversum (three), left colon (five), and sigmoid colon (two). Patient acceptance of the technique was good in 65%, medium in 20%, and poor in 15%. CONCLUSION For the first time we have demonstrated that CT-colonography has the potential ability to replace traditional colonoscopy in acromegalic patients. CT-colonography could be used as a screening modality for colon cancer in acromegaly.

Measurement of liver iron overload: Noninvasive calibration of MRI‐R2* by magnetic iron detector susceptometer

An accurate assessment of body iron accumulation is essential for the diagnosis and therapy of iron overload in diseases such as thalassemia or hemochromatosis. Magnetic iron detector susceptometry and MRI are noninvasive techniques capable of detecting iron overload in the liver. Although the transverse relaxation rate measured by MRI can be correlated with the presence of iron, a calibration step is needed to obtain the liver iron concentration. Magnetic iron detector provides an evaluation of the iron overload in the whole liver. In this article, we describe a retrospective observational study comparing magnetic iron detector and MRI examinations performed on the same group of 97 patients with transfusional or congenital iron overload. A biopsy‐free linear calibration to convert the average transverse relaxation rate in iron overload (R2 = 0.72), or in liver iron concentration evaluated in wet tissue (R2 = 0.68), is presented. This article also compares liver iron concentrations calculated in dry tissue using MRI and the existing biopsy calibration with liver iron concentrations evaluated in wet tissue by magnetic iron detector to obtain an estimate of the wet‐to‐dry conversion factor of 6.7 ± 0.8 (95% confidence level). Magn Reson Med, 2011.

Assessment of liver metastases from colorectal adenocarcinoma following chemotherapy: SPIO-MRI versus FDG-PET/CT

PurposeThis study compared superparamagnetic iron-oxide-enhanced magnetic resonance imaging (SPIO-MRI) and combined fluorodeoxyglucose positron emission tomography and computed tomography (FDG-PET/CT) in evaluating liver metastases from colorectal adenocarcinoma following chemotherapy.Materials and methodsNineteen patients were included in this retrospective study. SPIO-MRI and PET/CT results were compared with surgery, intraoperative ultrasound and pathology results in 11 patients and with the follow-up in eight patients.ResultsSPIO-MRI and PET/CT identified 125 and 71 metastases, respectively. False negative lesions were 11 for SPIO-MRI and 65 for PET/CT. In the whole study population, the per-lesion analysis of SPIO-MRI and PET/CT showed a sensitivity of 92% and 52% (p<0.001) and the per-segment analysis a sensitivity of 99% and 79% (p<0.001), respectively. In patients who underwent surgery, the per-lesion analysis of SPIO-MRI and PET/CT showed a sensitivity of 85% and 58% (p<0.05) and the per-segment analysis a sensitivity of 97% and 63% (p<0.05), respectively. In patients who underwent follow-up, the per-lesion analysis of SPIO-MRI and PET/CT showed a sensitivity of 97% and 47% (p<0.001) and the per-segment analysis a sensitivity of 100% and 63% (p<0.007), respectively. For lesions ≥15 and <30mm and for lesions <15 mm, SPIO-MRI demonstrated a higher sensitivity than PET/CT (p<0.001).ConclusionsSPIO-MRI appears superior to PET/CT in evaluating liver metastases from colorectal adenocarcinoma following chemotherapy.RiassuntoObiettivoScopo del presente lavoro è stato confrontare la superparamagnetic iron oxid-risonanza magnetica (SPIORM) e la tomografia computerizzata associata a tomografia a emissione di positroni con fluorodesossiglucosio (TC-PET-FDG) nella valutazione delle metastasi epatiche di adenocarcinoma colorettale dopo chemioterapia.Materiali e metodiDiciannove pazienti sono stati inclusi in questo studio. I risultati della SPIO-RM e della TC-PET sono stati confrontati con la chirurgia, l’ecografia intraoperatoria e l’anatomia patologica in 11 pazienti; con il follow-up in 8 pazienti.RisultatiLa SPIO-RM e la TC-PET hanno individuato 125 e 71 metastasi rispettivamente (falsi negativi: 11 e 65 rispettivamente). Considerando tutti i pazienti: analisi per lesione sensibilità del 92% per SPIO-RM e del 52% per TC-PET (p<0,001), analisi per segmento epatico sensibilità del 99% e del 79% (p<0,001) rispettivamente. Nei pazienti operati: analisi per lesione sensibilità del 85% per SPIO-RM e del 58% per TC-PET (p<0,05), analisi per segmento epatico sensibilità del 97% e del 63% (p<0,05) rispettivamente. Nei pazienti non operati in follow-up: analisi per lesione sensibilità del 97% per SPIO-RM e del 47% per TC-PET (p<0,001), analisi per segmento epatico sensibilità del 100% e del 63% (p<0,007) rispettivamente. La SPIO-RM ha dimostrato una sensibilità superiore alla TC-PET-FDG nella valutazione delle lesioni comprese tra 15 e 30 mm e delle lesioni <15 mm (p<0,001).ConclusioniLa SPIO-RM appare superiore alla TC-PET nella valutazione delle metastasi epatiche dopo chemioterapia

Value of bimodal (18)F-choline-PET/MRI and trimodal (18)F-choline-PET/MRI/TRUS for the assessment of prostate cancer recurrence after radiation therapy and radical prostatectomy.

Abstract Between 27% and 53% of all patients who undergo radical prostatectomy (RP) or radiation therapy (RT) as the first-line treatment of prostate cancer (PCa) develop a biochemical recurrence. Imaging plays a pivotal role in restaging by helping to distinguish between local relapse and metastatic disease (i.e., lymph-node and skeletal metastases). At present, the most promising tools for assessing PCa patients with biochemical recurrence are multiparametric magnetic resonance imaging (mpMRI) and positron emission tomography (PET)/computed tomography (CT) with radio-labeled choline derivatives. The main advantage of mpMRI is its high diagnostic accuracy in detecting local recurrence, while choline-PET/CT is able to identify lymph-node metastases when they are not suspicious on morphological imaging. The most recent advances in the field of fusion imaging have shown that multimodal co-registration, synchronized navigation, and combined interpretation are more valuable than the individual; separate assessment offered by different diagnostic techniques. The objective of the present essay was to describe the value of bimodal choline-PET/mpMRI fusion imaging and trimodal choline-PET/mpMRI/transrectal ultrasound (TRUS) in the assessment of PCa recurrence after RP and RT. Bimodal choline-PET/mpMRI fusion imaging allows morphological, functional, and metabolic information to be combined, thereby overcoming the limitations of each separate imaging modality. In addition, trimodal real-time choline-PET/mpMRI/TRUS fusion imaging may be useful for the planning and real-time guidance of biopsy procedures in order to obtain histological confirmation of the local recurrence.

Advantages of percutaneous abdominal biopsy under PET-CT/ultrasound fusion imaging guidance: a pictorial essay

Positron emission tomography (PET) is a functional imaging technique that can investigate the metabolic characteristics of tissues. Currently, PET images are acquired and co-registered with a computed tomography (CT) scan (PET-CT), which is employed for correction of attenuation and anatomical localization. In spite of the high negative predictive value of PET, false-positive results may occur; indeed, Fluorine 18 (18F)-fluorodeoxyglucose (18F-FDG) uptake is not specific to cancer. As 18F-FDG uptake may also be seen in non-malignant infectious or inflammatory processes, FDG-avid lesions may necessitate biopsy to confirm or rule out malignancy. However, some PET-positive lesions may have little or no correlative ultrasound (US) and/or CT findings (i.e., low conspicuity on morphological imaging). Since it is not possible to perform biopsy under PET guidance alone, owing to intrinsic technical limitations, PET information has to be integrated into a CT- or US-guided biopsy procedure (multimodal US/PET-CT fusion imaging). The purpose of this pictorial essay is to describe the technique of multimodal imaging fusion between real-time US and PET/CT, and to provide an overview of the clinical settings in which this multimodal integration may be useful in guiding biopsy procedures in PET-positive abdominal lesions.