Treatment outcome and pattern of failure in hepatoblastoma treated with a consensus protocol in Hong Kong.

BACKGROUND AND AIM: We reviewed the results and pattern of failure of the consensus HB/HCC 1996 treatment protocol for pediatric hepatoblastoma (HB) in Hong Kong. The role of SIOPEL and Children's Hepatic tumors International Collaboration (CHIC) risk stratification was evaluated. METHODS: Patients enrolled on the protocol from 1996 to 2014 were included. PRETEXT staging, SIOPEL, and CHIC risk groups were retrospectively assigned. RESULTS: Sixty patients were enrolled with median age at diagnosis of 1.1 years and median follow-up time of 6.8 years. Alpha-fetoprotein (AFP) was raised (>100 ng/mL) in 58 (97%) patients. Five (8%) had metastases at presentation and 7 (12%) experienced tumor rupture prior to or during treatment. Twenty-nine patients (48%) received a first-line cisplatin, 5-fluorouracil, and vincristine regimen only while 23 (38%) also had alternative chemotherapeutic agents. Hepatic resection could be performed in 48 (80%) patients. Three (5%) patients underwent upfront liver transplantation. Five-year event-free survival and overall survival rates were 69.2% ± 6.1% and 77.6% ± 5.5% respectively. Among the 16 patients with relapse/progression, 9 had intrahepatic failure only, 5 had distant failure only, and 2 had combined local and distant failure. Predictors of inferior outcome included advanced Evans staging, disease involving both lobes, rupture, low AFP, and suboptimal response to first-line chemotherapy. Assigned in 44 patients, PRETEXT staging, SIOPEL, and CHIC risk groups significantly predicted EFS and OS. CONCLUSIONS: Although the consensus HB/HCC 1996 protocol led to cure in three-quarters of pediatric HB patients, an upfront risk stratification system is required to identify and improve the outcome of high-risk patients.

Somatic PIK3CA mutations in seven patients with PIK3CA-related overgrowth spectrum.

Somatic mutations in PIK3CA cause many overgrowth syndromes that have been recently coined the "PIK3CA-Related Overgrowth Spectrum." Here, we present seven molecularly confirmed patients with PIK3CA-Related Overgrowth Spectrum, including patients with Congenital Lipomatous Overgrowth, Vascular Malformations, Epidermal Nevi, Scoliosis/Skeletal and Spinal syndrome, Klippel-Trenaunay syndrome, lymphatic malformation and two with atypical phenotypes that cannot be classified into existing disease categories. The literature on PIK3CA-Related Overgrowth Spectrum, suggests that PIK3CA c.1258T>C; p.(Cys420Arg), c.1624G>A; p.(Glu542Lys), c.1633G>A; p.(Glu545Lys), c.3140A>G; p.(His1047Arg), and c.3140A>T; p.(His1047Leu) can be identified in approximately 90% of patients without brain overgrowth. Therefore, droplet digital polymerase chain reaction targeting these mutation hotspots could be used as the first-tier genetic test on patients with PIK3CA-Related Overgrowth Spectrum who do not have signs of overgrowth in their central nervous system. © 2017 Wiley Periodicals, Inc.

Asian consortium on radiation dose of pediatric cardiac CT (ASCI-REDCARD).

BACKGROUND: With incremental utilization of pediatric cardiac CT in congenital heart disease, it is imperative to define its current radiation dose levels in clinical practice in order to help imagers optimize CT protocols, particularly in Asia and other developing countries where CT physicists are not readily available. OBJECTIVE: To evaluate current radiation dose levels and influencing factors in cardiac CT in children with congenital heart disease in Asia by conducting a retrospective multi-center, multi-vendor study. MATERIALS AND METHODS: We included 1,043 pediatric cardiac CT examinations performed in 8 centers between January 2014 and December 2014 to evaluate congenital heart disease. In five weight groups, we calculated radiation dose metrics including volume CT dose index, size-specific dose estimate, dose-length product and effective dose. Age at CT exam, gender, tube voltage, scan mode, CT indication and image reconstruction algorithm were analyzed to learn whether they influenced CT radiation dose. RESULTS: Volume CT dose index, size-specific dose estimate, dose-length product and effective dose of pediatric cardiac CT showed variations in the range of 4.3-23.8 mGy, 4.9-17.6 mGy, 55.8-501.3 mGy∙cm and 1.5-3.2 mSv, respectively, within five weight groups. Gender, tube voltage, scan mode and cardiac function assessment significantly influenced CT radiation dose. CONCLUSION: This multi-center, multi-vendor study demonstrated variations in radiation dose metrics of pediatric cardiac CT reflecting current practice in Asia. Gender, tube voltage, scan mode and cardiac function assessment should be considered as essential radiation dose-influencing factors in developing optimal pediatric cardiac CT protocols.

Myocardial iron load and fibrosis in long term survivors of childhood leukemia.

BACKGROUND: We sought to assess myocardial iron load and fibrosis, which may potentially affect cardiac function, in adult survivors of childhood leukemias and their relationships with left (LV) and right ventricular (RV) function. PROCEDURE: Fifty-eight (33 males) adult survivors, aged 24.5 ± 4.4, underwent cardiac magnetic resonance (CMR) at 16.6 ± 5.8 years after completion of treatment. Myocardial iron load and fibrosis were quantified using respectively T2* scan and late gadolinium enhancement. Right and left ventricular ejection fraction (EF) was measured by CMR, while myocardial function was assessed using tissue Doppler imaging. RESULTS: None of the survivors had significant myocardial iron overload (T2*<20 msec). The prevalence of LV and RV fibrosis was 9% (5/58) and 38% (22/58), respectively. Left ventricular EF was subnormal (EF 45-<55%) in 9% (5/58), while RV EF was abnormal (EF <45%) in 12% (7/58) and subnormal in 34% (20/58) of survivors. Patients with LV fibrosis had significantly lower mitral annular early diastolic velocity (P = 0.01) and smaller LV end-systolic volume (P = 0.02), while those with RV fibrosis had significantly lower tricuspid late diastolic annular velocity (P = 0.02) and early to late diastolic annular velocity ratio (P = 0.02) compared to those without. Cumulative anthracycline dose correlated with early diastolic mitral (r = -0.28, P = 0.038) and tricuspid (r = -0.40, P = 0.002) annular velocities, but not LV and RV EF or fibrosis (all P > 0.05). CONCLUSION: Ventricular fibrosis may occur in long term survivors of childhood leukemias and is related to diastolic function in the absence of significant myocardial iron overload.

A lucky and reversible cause of 'ischaemic bowel'.

An 81-year-old man was admitted with an infective exacerbation of chronic obstructive pulmonary disease. He also had clinical and radiological features suggestive of ileus. On day 6 after admission, he developed generalised abdominal pain. Urgent computed tomography of the abdomen showed presence of portovenous gas and dilated small bowel with pneumatosis intestinalis and whirl sign. Emergency laparotomy was performed, which showed a 7-mm perforated ulcer over the first part of the duodenum and small bowel volvulus. Omental patch repair and reduction of small bowel volvulus were performed. No bowel resection was required. The patient had a favourable outcome. Clinicians should suspect small bowel volvulus as a cause of ischaemic bowel. Presence of portovenous gas and pneumatosis intestinalis are normally considered to be signs of frank ischaemic bowel. The absence of bowel ischaemia at laparotomy in this patient shows that this is not necessarily the case and prompt surgical treatment could potentially save the bowels and lives of these patients.

Cumulative effective dose and cancer risk for pediatric population in repetitive full spine follow-up imaging: How micro dose is the EOS microdose protocol?

OBJECTIVE: To evaluate and to obtain analytic formulation for the calculation of the effective dose and associated cancer risk using the EOS microdose protocol for scoliotic pediatric patients undergoing full spine imaging at different age of exposure; to demonstrate the microdose protocol capable of delivering lesser radiation dose and hence of further reducing cancer risk induction when compared with the EOS low dose protocol; to obtain cumulative effective dose and cancer risk for both genders scoliotic pediatrics of US and Hong Kong population using the microdose protocol. METHODS: Organ absorbed doses of full spine exposed scoliotic pediatric patients have been simulated with the use of EOS microdose protocol imaging parameters input to the Monte Carlo software PCXMC. Gender and age specific effective dose has been calculated with the simulated organ absorbed dose using the ICRP-103 approach. The associated radiation induced cancer risk, expressed as lifetime attributable risk (LAR), has been estimated according to the method introduced in the Biological Effects of Ionizing Radiation VII report. Values of LAR have been estimated for scoliotic patients exposed repetitively during their follow up period at different age for US and Hong Kong population. RESULTS: The effective doses of full spine imaging with simultaneous posteroanterior and lateral projection for patients exposed at the age between 5 and 18 years using the EOS microdose protocol have been calculated within the range of 2.54-14.75 µSv. The corresponding LAR for US and Hong Kong population was ranged between 0.04 × 10-6 and 0.84 × 10-6. Cumulative effective dose and cancer risk during follow-up period can be estimated using the results and are of information to patients and their parents. CONCLUSION: With the use of computer simulation and analytic formulation, we obtained the cumulative effective dose and cancer risk at any age of exposure for pediatric patients of US and Hong Kong population undergoing repetitive microdose protocol full spine imaging. Girls would be at a statistically significant higher cumulative cancer risk than boys undergoing the same microdose full spine imaging protocol and the same follow-up schedule.

A recurrent de novo DYNC1H1 tail domain mutation causes spinal muscular atrophy with lower extremity predominance, learning difficulties and mild brain abnormality.

We describe four unrelated patients with the same de novo heterozygous missense mutation c.751C>T in the DYNC1H1 gene. We found a high phenotype-genotype correlation with all four patients having early childhood-onset predominant lower limb muscle weakness and wasting which was slowly progressing and later-onset mild upper extremities proximal weakness. All four patients presented minor cognitive dysfunction with learning difficulty and developmental behavioural comorbidities with mild abnormalities in the brain MRI. The leg muscle MRI findings are highly consistent in DYN1CH1-related spinal muscular atrophy with lower limb predominance (SMALED) with relative sparing of biceps femoris and semitendinosus, and hypertrophy of adductor longus in the thighs; and sparing the anterior and medial muscles in the calves. This report provides important clinical evidence indicating the de novo heterozygous missense mutation c.751C>T in the DYNC1H1 gene is pathogenic causing SMALED. Muscle MRI is more specific than muscle biopsy in the diagnosis of SMALED.

Identification of mutations in the PI3K-AKT-mTOR signalling pathway in patients with macrocephaly and developmental delay and/or autism.

Background: Macrocephaly, which is defined as a head circumference greater than or equal to + 2 standard deviations, is a feature commonly observed in children with developmental delay and/or autism spectrum disorder. Although PTEN is a well-known gene identified in patients with this syndromic presentation, other genes in the PI3K-AKT-mTOR signalling pathway have also recently been suggested to have important roles. The aim of this study is to characterise the mutation spectrum of this group of patients. Methods: We performed whole-exome sequencing of 21 patients with macrocephaly and developmental delay/autism spectrum disorder. Sources of genomic DNA included blood, buccal mucosa and saliva. Germline mutations were validated by Sanger sequencing, whereas somatic mutations were validated by droplet digital PCR. Results: We identified ten pathogenic/likely pathogenic mutations in PTEN (n = 4), PIK3CA (n = 3), MTOR (n = 1) and PPP2R5D (n = 2) in ten patients. An additional PTEN mutation, which was classified as variant of unknown significance, was identified in a patient with a pathogenic PTEN mutation, making him harbour bi-allelic germline PTEN mutations. Two patients harboured somatic PIK3CA mutations, and the level of somatic mosaicism in blood DNA was low. Patients who tested positive for mutations in the PI3K-AKT-mTOR pathway had a lower developmental quotient than the rest of the cohort (DQ = 62.8 vs. 76.1, p = 0.021). Their dysmorphic features were non-specific, except for macrocephaly. Among the ten patients with identified mutations, brain magnetic resonance imaging was performed in nine, all of whom showed megalencephaly. Conclusion: We identified mutations in the PI3K-AKT-mTOR signalling pathway in nearly half of our patients with macrocephaly and developmental delay/autism spectrum disorder. These patients have subtle dysmorphic features and mild developmental issues. Clinically, patients with germline mutations are difficult to distinguish from patients with somatic mutations, and therefore, sequencing of buccal or saliva DNA is important to identify somatic mosaicism. Given the high diagnostic yield and the management implications, we suggest implementing comprehensive genetic testing in the PI3K-AKT-mTOR pathway in the clinical evaluation of patients with macrocephaly and developmental delay and/or autism spectrum disorder.

Plasma Levels of High Sensitivity Cardiac Troponin T in Adults with Repaired Tetralogy of Fallot.

Detectable low circulating level of cardiac troponin T (cTnT) may reflect subclinical myocardial injury. We tested the hypothesis that circulating levels of hs-cTnT are altered in adults with repaired tetralogy of Fallot (TOF) and associated with ventricular volume load and function. Eighty-eight TOF patients and 48 controls were studied. Plasma hs-cTnT levels were determined using a highly sensitive assay (hs-cTnT). The right (RV) and left ventricular (LV) volumes and ejection fraction (EF) were measured using 3D echocardiography and, in 52 patients, cardiac magnetic resonance (CMR). The median (interquartile range) for male and female patients were 4.87 (3.83-6.62) ng/L and 3.11 (1.00-3.87) ng/L, respectively. Thirty percent of female but none of the male patients had increased hs-cTnT levels. Female patients with elevated hs-cTnT levels, compared to those without, had greater RV end-diastolic and end-systolic volumes and LV systolic dyssynchrony index (all p < 0.05). For patient cohort only, hs-cTnT levels correlated positively with CMR-derived RV end-diastolic volume and negatively with echocardiography-derived LV and RV EF (all p < 0.05). Multiple linear regression identified sex and RV EF as significant correlates of log-transformed hs-cTnT levels. Increased hs-cTnT levels occur in 30% of female patients after TOF repair, and are associated with greater RV volumes and worse RV EF.

Right ventricular mechanics in adults after surgical repair of tetralogy of fallot: insights from three-dimensional speckle-tracking echocardiography.

BACKGROUND: The clinical relevance of evaluating right ventricular (RV) myocardial deformation in congenital heart disease is increasingly recognized. The aim of this study was to explore, using three-dimensional (3D) speckle-tracking echocardiography, RV mechanics in terms of 3D global area strain and mechanical dyssynchrony in adults with repaired tetralogy of Fallot. METHODS: Twenty patients (12 men) aged 24.7 ± 8.6 years and 22 age-matched controls (11 men) were studied. Global RV peak area strain and area strain-derived systolic dyssynchrony index (SDI) were determined using 3D speckle-tracking echocardiography. RV end-diastolic volume and end-systolic volume, ejection fraction (EF), and pulmonary regurgitation fraction were measured in patients using cardiac magnetic resonance. RESULTS: Coefficients of variation for intraobserver and interobserver measurements of RV global area strain were 6.1% and 7.9%, respectively, and those for SDI were 7.6% and 10.1%, respectively. Compared with controls, patients had significantly lower global area strain (P = .005) and greater SDI (P = .008). The prevalence of RV mechanical dyssynchrony (SDI > control mean + 2 SDs) in patients was 30%. In patients, global area strain correlated inversely with SDI (r = -0.42, P = .04), RV end-diastolic volume (r = -0.48, P = .032), and RV end-systolic volume (r = -0.48, P = .031) and positively with EF (r = -0.51, P = .02), while RV SDI correlated positively with RV end-systolic volume (r = 0.55, P = .012), pulmonary regurgitation fraction (r = 0.54, P = .031), and QRS duration (r = 0.51, P = .022) and negatively with RV EF (r = -0.62, P = .004). Multivariate analysis showed that RV EF (ß = 0.22, P = .048) was a significant correlate of global area strain in patients. CONCLUSIONS: In adults after tetralogy of Fallot repair, 3D RV deformation is impaired in association with RV dyssynchrony, volume overloading, and reduced EF.

Merosin-deficient congenital muscular dystrophy (MDCMD): a case report with MRI, MRS and DTI findings.

Congenital muscular dystrophy (CMD) comprises a heterogeneous group of disorders present at birth with muscle weakness, hypotonia and contractures. Congenital muscular dystrophy (CMD) comprises a heterogeneous group of disorders with muscle weakness, hypotonia and contractures present at birth. A particular subset of classic CMD is characterized by a complete absence of merosin. Merosin-deficient congenital muscular dystrophy (MDCMD) is a rare genetic disease involving the central and peripheral nervous system in the childhood. High signal intensities are often observed throughout the centrum semiovale, periventricular, and sub-cortical white matters on T2-weighted images in MRI brain in children with MDCMD. Apparent diffusion coefficient (ADC) map may reveal increased signal intensity and apparent diffusion coefficient values in the periventricular and deep white matters. These white matter findings, observed in late infancy, decrease in severity with age. The pathogenesis of these changes remains uncertain at present. In this article, we outline the specific MR imaging findings seen in a patient with documented MDCMD and also suggest the causes.

Lactobacillus rhamnosus hepatic abscess associated with Mirizzi syndrome: a case report and review of the literature.

The clinical significance of Lactobacillus spp. isolated from clinical specimens has often been overlooked due to its low virulence. We report the first case of life-threatening bacteremic liver abscess due to Lactobacillus rhamnosus associated with Mirizzi syndrome in a 74-year-old Chinese man. Literature on sporadic reports of Lactobacillus liver abscess is reviewed.