Diffusion MRI for rectal cancer staging: ADC measurements before and after ultrasonographic gel lumen distension.

OBJECTIVES: To compare Apparent Diffusion Coefficient (ADC) measurements in rectal neoplastic lesions before and after lumen distension obtained with sonography transmission gel. METHODS: From January 2014 to July 2016, 25 patients (average age 63.7, range 41-85, 18 males) were studied for pre-treatment rectal cancer staging using a 1.5T MRI. Diffusion MRI was obtained using echo-planar imaging with b=800 value; all patients were studied acquiring diffusion sequences with and without rectal lumen distension obtained using sonography transmission gel. In both diffusion sequences, two blinded readers calculated border ADC values and small ADC values, drawing regions of interest respectively along tumour borders and far from tumour borders. Mean ADC values among readers - for each type of ADC measurement - were compared using Wilcoxon matched pairs signed rank test. Correlation was assessed using Pearson analysis. RESULTS: Border ADC mean value for diffusion MR sequences without endorectal contrast was 1.122mm2/sec, with 95% Confidence Interval (CI)=1.02-1.22; using gel lumen distension, higher border ADC mean value of 1.269mm2/s (95% CI=1.16-1.38) was obtained. Wilcoxon matched pairs signed rank test revealed statistical difference (p<0.01); a strong Pearson correlation was reported, with r value of 0.69. Small-ADC mean value was 1.038mm2/s (95% CI=0.91-1.16) for diffusion sequences acquired without endorectal distension and 1.127mm2/s (95% CI=0.98-1.27) for diffusion sequences obtained after endorectal gel lumen distension. Wilcoxon analysis did not show statistical difference (p=0.13). A very strong positive correlation was observed, with r value of 0.81. CONCLUSIONS: ADC measurements are slightly higher using endorectal sonographic transmission gel; ROI should be traced far from tumour borders, to minimize gel filled-pixel along the interface between lumen and lesion. Further studies are needed to investigate better reliability of ADC in rectal cancer MRI using sonographic gel intraluminal distension.

Childhood neurofibromatosis type 2 (NF2) and related disorders: from bench to bedside and biologically targeted therapies.

Neurofibromatosis type 2 [NF2; MIM # 101000] is an autosomal dominant disorder characterised by the occurrence of vestibular schwannomas (VSs), schwannomas of other cranial, spinal and cutaneous nerves, cranial and spinal meningiomas and/or other central nervous system (CNS) tumours (e.g., ependymomas, astrocytomas). Additional features include early onset cataracts, optic nerve sheath meningiomas, retinal hamartomas, dermal schwannomas (i.e., NF2-plaques), and (few) café-au-lait spots. Clinically, NF2 children fall into two main groups: (1) congenital NF2 - with bilateral VSs detected as early as the first days to months of life, which can be stable/asymptomatic for one-two decades and suddenly progress; and (2) severe pre-pubertal (Wishart type) NF2- with multiple (and rapidly progressive) CNS tumours other-than-VS, which usually present first, years before VSs [vs. the classical adult (Gardner type) NF2, with bilateral VSs presenting in young adulthood, sometimes as the only disease feature]. Some individuals can develop unilateral VS associated with ipsilateral meningiomas or multiple schwannomas localised to one part of the peripheral nervous system [i.e., mosaic NF2] or multiple non-VS, non-intradermal cranial, spinal and peripheral schwannomas (histologically proven) [schwannomatosis]. NF2 is caused by mutations in the NF2 gene at chromosome 22q12.1, which encodes for a protein called merlin or schwannomin, most similar to the exrin-readixin-moesin (ERM) proteins; mosaicNF2 is due to mosaic phenomena for the NF2 gene, whilst schwannomatosis is caused by coupled germ-line and mosaic mutations either in the SMARCB1 gene [SWNTS1; MIM # 162091] or the LZTR1 gene [SWNTS2; MIM # 615670] both falling within the 22q region and the NF2 gene. Data driven from in vitro and animal studies on the merlin pathway [e.g., post-translational and upstream/downstream regulation] allowed biologically targeted treatment strategies [e.g., Lapatinib, Erlotinib, Bevacizumab] aimed to multiple tumour shrinkage and/or regression and tumour arrest of progression with functional improvement.

Cystic pancreatic neoplasms: diagnosis and management emphasizing their imaging features.

The incidence of cystic pancreatic neoplasms increased in the past decade, due to the recent advances in multidetector computed tomography and magnetic resonance imaging; several pancreatic cysts are incidentally encountered during diagnostic exams performed for non-pancreatic diseases. Indeed, cystic pancreatic tumors are currently considered relatively rare, accounting for approximately 10% of all pancreatic neoplasms. Serous cystadenoma, mucinous cystadenoma, intraductal papillary mucinous neoplasms and solid-pseudopapillary tumor represent about 90% of all pancreatic primary cystic tumours. The non-optimal diagnostic preoperative accuracy in distinguishing benign from malignant cystic lesions ensures that up till now there are no well-defined guidelines regarding the management of cystic pancreatic neoplasms. Imaging findings often do not allow the diagnosis, because there is a considerable overlap among the cystic lesions; the best pre-operative characterization is obtained by the association of all diagnostic procedures available. For their different histology and behavior, cystic pancreatic neoplasms need to be managed according to various factors. In this review, the main elements necessary for their management are assessed--radiological features, tumour dimensions, patients' characteristics, the mode of clinical presentation and the associated oncologic markers. A multidisciplinary approach--including gastroenterologists, radiologists and surgeons--should be adopted in order to perform a differential diagnosis and a correct management.

Endometrial carcinoma: MR staging and causes of error.

PURPOSE: This study was undertaken to prospectively determine the diagnostic capabilities of magnetic resonance (MR) imaging in detecting myometrial and cervical invasion and lymph node involvement in endometrial carcinoma and to identify the causes of errors in staging endometrial carcinoma. MATERIALS AND METHODS: Twenty consecutive patients with a histological diagnosis of endometrial carcinoma underwent preoperative MR imaging. MR findings were compared with surgical staging, considered as the standard of reference. RESULTS: In assessing myometrial invasion, MR imaging showed 70% accuracy, 80% sensitivity, 40% specificity, 80% positive predictive value (PPV), and 40% negative predictive value (NPV). In detecting cervical invasion, MR imaging had 95% accuracy, 100% sensitivity, 94.4% specificity, 66.7% PPV, and 100% NPV. In evaluating lymph node involvement, MR imaging showed 100% accuracy, sensitivity, specificity, PPV and NPV. Errors in evaluating myometrial invasion were caused by polypoid tumour, adenomyosis and leiomyomas, whereas those in evaluating cervical invasion were caused by dilatation and curettage. CONCLUSIONS: MR imaging is a reliable technique for preoperative evaluation of endometrial carcinoma. Its main limitation is differentiating between stage IA and IB carcinomas, which is not highly important for surgical planning. Cooperation between the gynaecologist and radiologist is mandatory to avoid staging errors.

Magnetic resonance with diffusion-weighted imaging in the evaluation of transplanted kidneys: updating results in 35 patients.

BACKGROUND: We compared values of apparent diffusion coefficient (ADC) with renal function indices among a population of kidney transplant recipients who underwent magnetic resonance with diffusion-weighted imaging (DWI) of their grafts. MATERIALS AND METHODS: Thirty-five patients with right iliac transplanted kidneys were studied using 1.5-T magnetic resonance. Diffusion echo-planar sequences with several b-values were acquired to investigate transplanted grafts. Patients were divided into 3 groups according to their creatinine clearances; Group A, clearance >60 mL/min; Group B, clearance >30 and ≤60 mL/min; and Group C, clearance ≤30 mL/min. ADC values between groups were compared using Mann-Whitney U test. Receiver operating characteristic (ROC) curves were used to predict the normal function (Group A) versus renal failure cohorts (Group C). RESULTS: Comparing mean values of ADC between Group A and Group C patients, we observed a significant difference (P = .0003) with higher ADC values among patients with a normal creatinine clearance (>60 mL/min). Comparing Groups B and C did not show a significant difference (P = .05); nor did Group A and Group B reveal a significant difference (P = .38). To predict normal clearance values, the Group A ROC curve showed an area under curve (AUC) of 0.780 with a sensitivity of 92.3% and a specificity of 68.2% at a threshold ADC value of ≥2.08 × 10(-3) mm(2)/sec. In the prediction of low clearance values, the Group C ROC curve showed an AUC of 0.846 with a sensitivity of 83.3% and a specificity of 82.6% using a threshold ADC value of ≤2.07 × 10(-3) mm(2)/sec. CONCLUSIONS: Updating our experience among 35 patients, DWI was confirmed to be a promising noninvasive tool to assess renal function; an ADC ≥2.08 × 10(-3) mm(2)/sec may be used as a threshold to predict a normal clearance. However, an overlap of ADC values between groups is a limit.

Redox regulation of cellular stress response in multiple sclerosis.

Multiple sclerosis (MS) is an autoimmune-mediated neurodegenerative disease with characteristic foci of inflammatory demyelination in the brain, spinal cord, and optic nerves. Recent studies have demonstrated not only that axonal damage and neuronal loss are significant pathologic components of MS, but that this neuronal damage is thought to cause the permanent neurologic disability often seen in MS patients. Emerging finding suggests that altered redox homeostasis and increased oxidative stress, primarily implicated in the pathogenesis of MS, are a trigger for activation of a brain stress response. Relevant to maintenance of redox homeostasis, integrated mechanisms controlled by vitagenes operate in brain in preserving neuronal survival during stressful conditions. Vitagenes encode for heat shock proteins (Hsp) Hsp32, Hsp70, the thioredoxin and the sirtuin protein systems. In the present study we assess stress response mechanisms in the CSF, plasma and lymphocytes of control patients compared to MS patients. We found that the levels of vitagenes Hsp72, Hsc70, HO-1, as well as oxidative stress markers carbonyls and hydroxynonenals were significantly higher in the blood and CSF of MS patients than in control patients. In addition, an increased expression of Trx and sirtuin 1, together with a decrease in the expression of TrxR were observed. Our data strongly support a pivotal role for redox homeostasis disruption in the pathogenesis of MS and, consistently with the notion that new therapies that prevent neurodegeneration through nonimmunomodulatory mechanisms can have a tremendous potential to work synergistically with current MS therapies, unravel important targets for new cytoprotective strategies.

Magnetic resonance with diffusion-weighted imaging in the evaluation of transplanted kidneys: preliminary findings.

BACKGROUND: The aim of this study was to compare values of apparent diffusion coefficient (ADC) and diffusion (D) with renal function indexes, in a population of kidney transplant recipients who underwent magnetic resonance with diffusion-weighted imaging (DWI) of the transplanted graft. MATERIALS AND METHODS: We studied 21 patients using a 1.5-Tesla magnetic resonance; DWI sequences were acquired with several b-values. Patients were divided into 3 groups by their creatinine clearance values: group A, clearance >60 mL/min; group B, clearance >30 and ≤60 mL/min; and group C, clearance ≤30 mL/min. ADCs values between groups were compared using the Mann-Whitney U test. Receiver operating characteristic (ROC) curves were created for prediction of normal renal function (group A) and renal failure (group C). RESULTS: Comparing mean values of ADC between groups A and C, we observed a difference (P=0.0012), with higher values in group A. Regarding mean values of D, we observed a difference between groups A and C (P=0.022). In the comparison between contiguous groups, we observed no difference for ADC and D values. In the prediction of normal clearance values (group A), ROC curve showed an area under curve (AUC) of 0.861, with a sensitivity of 88.89% and specificity of 75% using a threshold ADC value ≥2.1 × 10(-3) mm(2)/sec. For prediction of normal clearance values (group A), ROC curve showed an AUC of 0.787, with a sensitivity of 77.8% and specificity of 83.3% using a threshold D value ≥2.3 × 10(-3) mm(2)/sec. CONCLUSION: Although studies with a larger number of patients are needed, DWI represents a promising tool for noninvasive assessment of renal function. An ADC ≥ 2.1 × 10(-3) mm(2)/sec and a D ≥ 2.3 × 10(-3) mm(2)/sec may be used as a threshold for predicting normal clearance.

Magnetic resonance cholangiopancreatography and contrast-enhanced magnetic resonance cholangiopancreatography versus endoscopic ultrasonography in the diagnosis of extrahepatic biliary pathology.

PURPOSE: This study compared the diagnostic accuracy of magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasonography (EUS) in evaluating the cause of extrahepatic bile duct dilatation. MATERIALS AND METHODS: Forty-five patients (26 men, mean age 57 years) with extrahepatic biliary dilatation, as shown by transabdominal ultrasound, with or without elevated biliary and pancreatic serum indices, were prospectively studied with MRCP and EUS between September 2007 and October 2008. EUS and MRCP were performed within no more than 24 h of each other to reduce the possibility of changes due to stone migration. Image analysis was carried out in a double-blind fashion. RESULTS: MRCP had 88.9% diagnostic accuracy, 91.9% sensitivity and 75% specificity, with 94.4% positive predictive value and 66.7% negative predictive value. EUS had 93.3% diagnostic accuracy, 97.3% sensitivity and 75% specificity; the positive and negative predictive values were 94.7% and 85.7%, respectively. CONCLUSIONS: MRCP and EUS do not show significant statistical differences in diagnostic accuracy. MRCP is an accurate, noninvasive modality in the study of extrahepatic biliary pathology. EUS is especially reliable in patients with extrahepatic biliary obstruction caused by endoluminal sludge.

Evaluation of the biliary and pancreatic system with 2D SSFSE, breathhold 3D FRFSE and respiratory-triggered 3D FRFSE sequences.

PURPOSE: The authors compared biliary and pancreatic imaging obtained through 2D single-shot fast spin-echo (SSFSE), breath-hold 3D fast recovery fast spin-echo (FRFSE) and respiratory-triggered 3D FRFSE sequences. MATERIALS AND METHODS: A total of 106 magnetic resonance cholangiopancreatography (MRCP) examinations performed between December 2007 and September 2008 were evaluated with a comparison of 2D SSFSE (thin section and thick slab), breath-hold 3D FRFSE and respiratory-triggered 3D FRFSE sequences. The biliary tract was divided into seven segments: right hepatic duct, left hepatic duct, common hepatic duct, cystic duct, common bile duct, cystic duct junction and biliary-pancreatic confluence. The main pancreatic duct was divided into three segments (head, body and tail). Visualisation of biliary variants was also compared. Two blinded radiologists evaluated segment visibility using a quantitative scale. The Student's t test for paired samples was used for statistical analysis. RESULTS: Compared with 2D SSFSE, respiratory-triggered 3D FRFSE sequences showed better visibility of the right hepatic duct (p=0.0277), the cystic duct (p=0.0081), the cystic duct junction (p=0.0010), the biliary-pancreatic confluence (p=0.0334) and biliary variants (p=0.0198). In the comparison between breath-hold 3D FRFSE and 2D SSFSE, a significant statistical difference was found in visualisation of the cystic duct (p=0.027), the cystic duct junction (p=0.020), the biliary-pancreatic confluence (p=0.0338) and biliary variants (p=0.0311). CONCLUSIONS: Three-dimensional FRFSE offers a significant benefit over conventional 2D imaging.

Thymic carcinoma, systemic lupus erythematosus, and hypertrophic pulmonary osteoarthropathy in an 11-year-old boy: a novel association.

Thymic carcinoma is exceptionally rare in children and it has never previously been associated with autoimmune disorders. The authors report the case of an 11-year-old boy with thymic carcinoma, hypertrophic pulmonary osteoarthropathy, and an autoimmune disease that resembled systemic lupus erythematosus. To their knowledge, this is the first case of such complex clinical findings. The tumor was of high grade histologically and the boy died after 1 year, in spite of chemotherapy and radiotherapy. A review is presented of the available medical literature on thymic malignancy in childhood.

Thrombectomy of the inferior vena cava from recurrent low-grade endometrial stromal sarcoma: case report and review of the literature.

We report a rare case in which a patient successfully underwent surgical removal from the inferior vena cava of a neoplastic thrombus induced by a recurrent low-grade endometrial stromal sarcoma. The patient was admitted with severe acute renal failure and a large edema on the right lower extremity. One year previously she had undergone hysterectomy and adnexectomy due to an endometrial stromal sarcoma with involvement of the tuba. Because of complete thrombosis of the right internal and common iliac veins and the inferior vena cava, she underwent thrombectomy of the inferior vena cava. The postoperative course was complicated by hydruric renal failure induced by a acute tubular necrosis. At 6-month follow-up, the patient was asymptomatic with normal renal function. The ileocaval axis was patent on magnetic resonance imaging. Only 5 cases of intracaval extension of endometrial stromal sarcoma have been reported. Surgical treatment is viable due to excellent prognosis of the low-grade endometrial stromal sarcoma (80-100% 5-year survival) and likely fatal heart failure in untreated cases.

Megacalycosis on duplex system upper moiety.

The authors report a rare case of megacalycosis located on a duplex system upper moiety, and analyse the problems related to its pathology, etiopathogenesis, clinical manifestations and diagnosis.

Hepatobiliary cystadenoma with hyaline stroma : A pediatric case associated with multiple hemangiomas.

The authors describe a case of hepatobiliary cystadenoma and its pathogenetic, histopathologic, and clinical aspects and point out its association with multiple hemangiomas.

Aneurysmal bone cyst of the acromion: a case report.

The case of 6-year-old girl with an asymptomatic aneurysmal bone cyst of the acromion is reported. Such tumors are rarely located in the scapula and are especially rare in the acromion. The diagnosis was confirmed by biopsy and surgical resection of the lesion. Roentgenographic, CT and histologic features of the cyst are discussed.

[A case of hepatocarcinoma preceded by several years by "isolated" increase in alphafetoprotein]. / Un caso di epatocarcinoma preceduto per anni da aumento "isolato" dell'alfafetoproteina.

Hepatocarcinoma (HCC), the most frequent malignant hepatic neoplasia, is sometimes difficult to diagnose at an early stage since the symptoms may be attributed to concomitant hepatic cirrhosis. The assay of alpha-fetoprotein associated with an ultrasound examination of the hepatic parenchyma is an important screening tool for high-risk patients. Ultrasound examination is considered the most sensitive method and alpha-fetoprotein is a supplementary diagnostic tool. Elevated alpha-fetoprotein only occasionally precedes morphological anomalies and even in these cases the neoplastic aspect emerges within a short period of time. The case reported here illustrates the "astronomic" increase of alpha-fetoprotein in a high-risk patient for HCC (positive HBsAg cirrhosis) without the manifest appearance of any instrumental or histological data confirming the presence of the tumour for two years. When the tumour was identified in instrumental tests it had spread throughout the entire hepatic parenchyma in a form which could no longer be treated using any form of therapy. The case reported here emphasizes the diagnostic value of alphafetoprotein in high-risk patients for HCC, even in the prolonged absence of all other data regarding neoplastic transformation.