Does intra-tumoural fat on MRI predict visibility of small (≤3 cm) hepatocellular carcinomas during ultrasound-guided tumour ablation?

AIM: To assess if intra-tumoural fat on magnetic resonance imaging (MRI) affects the ultrasonographic (US) visibility of small (≤3 cm) hepatocellular carcinomas (HCC) during radiofrequency ablation (RFA). MATERIALS AND METHODS: Institutional review board approval was obtained. A retrospective review of all patients who underwent image-guided ablation between 1 January 2010 and 31 April 2015 was performed. Patients with HCC who underwent US RFA were included. Inclusion criteria included small tumours (≤3 cm), treatment-naive cases or new focus of HCC in a different and untreated segment, and pre-procedural MRI. The presence of intra-tumoural fat was determined retrospectively via in-and-out-of-phase MRI. Other factors that potentially affect ultrasonographic visibility, such as background fatty liver, presence of cirrhosis, tumour size, and distance from diaphragm, were recorded. RESULTS: Ninety procedures performed on 74 patients (62 men and 12 women; mean age: 67.3 years; range: 39-88 years). Seventy-two tumours were visible on US (hypoechoic n=35, hyperechoic n=28, heterogeneous n=9). Intra-tumoural fat was seen in 23 tumours (25.6%, hyperechoic n=17, hypoechoic n=6). The presence of intra-tumoural fat (p=0.005) and distance from diaphragm (p=0.007) were found to be statistically significant factors affecting tumour visibility on planning US. The presence of background fatty liver (p=0.485), cirrhosis (p=0.48), and tumour size (p=0.15) were not found to be significant. CONCLUSION: The present study shows that the presence of intra-tumoural fat in small HCCs on pre-procedural MRI can accurately predict their visibility on planning US during percutaneous tumour ablation.

Predicting early recurrence of hepatocellular carcinoma with texture analysis of preoperative MRI: a radiomics study.

AIM: To investigate the feasibility of using texture analysis in preoperative magnetic resonance imaging (MRI) to predict early recurrence (ER) in hepatocellular carcinoma (HCC) post-curative surgery. MATERIAL AND METHODS: Institutional review board was obtained. A retrospective review of all patients who underwent hepatectomy between 1 January 2007 and 31 December 2015 was performed. Inclusion criteria included preoperative MRI, tumour size ≥1 cm, new cases of HCC. Exclusion criteria included loss to follow-up, ruptured HCCs, movement artefacts, and previous hepatectomy or interval adjuvant therapy. Patients were divided into ER and late or no recurrence (LNR) groups. ER was defined as new foci of HCC within 730 days of curative surgery. Radiomics feature extraction was performed on T2, diffusion-weighted imaging (DWI), T1 arterial, and T1 portovenous acquisitions on MATLAB (Mathworks, Matick, MA, USA). The MaZda software was used to analyse 290 texture parameters and PRTools was used for feature selection. RESULTS: Fifty patients (43 male, mean age 67 years) were divided into ER (n=20) and LNR (n=30) groups. Serum alpha-fetoprotein level (p=0.026), serum É£-glutamyltranspeptidase (p=0.014), Child-Pugh score (p=0.02) and the presence of vascular invasion (gross and/or microvascular, p=0.025) were found to be statistically significant different between the two groups. Parameters S(4,0)SumVarnc, S(0,3)SumOfSqs, and S(1,1)DifVarnc of the equilibrium phase were most accurate, achieving 84%, 82%, and 78% accuracy, respectively. CONCLUSION: Texture analysis of preoperative MRI has the potential to predict ER of HCC with up to 84% accuracy using an appropriate, single texture analysis parameter. Future studies are needed to validate these findings.

Replication study of SNP associations for colorectal cancer in Hong Kong Chinese.

BACKGROUND: Recent genome-wide association studies of colorectal cancer (CRC) have identified common single-nucleotide polymorphisms (SNPs) mapping to 10 independent loci that confer modest increased risk. These studies have been conducted in European populations and it is unclear whether these observations generalise to populations with different ethnicities and rates of CRC. METHODS: An association study was performed on 892 CRC cases and 890 controls recruited from the Hong Kong Chinese population, genotyping 32 SNPs, which were either associated with CRC in previous studies or are in close proximity to previously reported risk SNPs. RESULTS: Twelve of the SNPs showed evidence of an association. The strongest associations were provided by rs10795668 on 10p14, rs4779584 on 15q14 and rs12953717 on 18q21.2. There was significant linear association between CRC risk and the number of independent risk variants possessed by an individual (P=2.29 × 10(-5)). CONCLUSION: These results indicate that some previously reported SNP associations also impact on CRC risk in the Chinese population. Possible reasons for failure of replication for some loci include inadequate study power, differences in allele frequency, linkage disequilibrium structure or effect size between populations. Our results suggest that many associations for CRC are likely to generalise across populations.

No association between T102C polymorphism of serotonin-2A receptor gene and clinical phenotypes of Chinese schizophrenic patients.

Serotonin dysfunction has been implicated in the pathogenesis of schizophrenia. Previous studies have shown an association between the T102C polymorphism of the 5HT2a receptor gene and schizophrenia. However, negative findings have also been reported. One possible explanation for such discrepancy is disease heterogeneity due to the current limitations in the diagnosis of schizophrenia. We conducted a case-control study of the T102C polymorphism with detailed characterisation of the clinical phenotypes to investigate the possible association with schizophrenia not only at the diagnostic level, but also with reference to other clinical phenotypes potentially related to serotonin dysfunction. Four hundred and seventy-one biologically unrelated schizophrenic patients and 523 unrelated healthy controls of Han Chinese descent in Hong Kong were compared for genotypes and allele frequencies of the T102C polymorphism by PCR amplification and restriction analysis. No evidence of association was detected at the diagnostic level and various clinical phenotypes. However, we found a trend association with small effect size between genotype 102T/102C and patients with better verbal fluency and less motor co-ordination soft neurological signs. There is a need for future large-scale studies on the possible associations between genetic polymorphisms and neurocognitive function impairments in schizophrenia.