Clinical value of contrast-enhanced computed tomography (CECT) combined with contrast-enhanced ultrasound (CEUS) for characterization and diagnosis of small nodular lesions in liver.

OBJECTIVES: To explore the clinical value of contrast-enhanced computed tomography (CECT) combined with contrast-enhanced ultrasound (CEUS) for characterization and diagnosis of small nodular lesions in the liver and investigate the association between such small nodular lesions and the degree of tumor differentiation. METHODS: Combined imaging modalities were performed on 120 patients who were admitted by Linyi Maternal and Child Health hospital from December 2018 to December 2020 and diagnosed with hepatic nodular lesions. The CT scans were interpreted by two senior imageologists while the ultrasound scans were analyzed by two senior sonographers. A comparative analysis was carried out on different scan modes and the postoperative or post-puncture pathological results using the t-test, the χ2 test, and the Pearson's correlation analysis. RESULTS: Compared to the pathological results, definite diagnoses of 55 malignant cases were made using CECT alone, with the coincidence rate of 78.6%; CECT combined with CEUS formed correct diagnoses in 64 cases, and the coincidence rate was up to 91.4%. The difference between the two scan modes was statistically significant (p= 0.03). Based on pathological diagnosis, seventy out of the 120 cases of small nodular lesions were identified as malignant, while the other 50 cases were benign. The single imaging modality diagnosed 63 malignant and 57 benign nodules, whereas the combined modalities identified 68 malignancies and 52 benign conditions. Compared to CECT as a single imaging modality, the combined modalities showed a higher degree of sensitivity and accuracy, and the difference was statistically significant (sensitivity: p= 0.03; accuracy: p= 0.02); in the malignant cases, the magnitudes of contrast enhancement of CT and ultrasound imaging decreased with an increase in the degree of differentiation, indicating a negative correlation between these factors. CONCLUSIONS: CECT combined with CEUS has a higher coincidence rate, greater sensitivity, and better diagnostic accuracy when being used for characterization and diagnosis of small nodular lesions in the liver. A higher degree of tumor differentiation means a decreased magnitude of contrast enhancement and a blurrier boundary, which indicates that CECT and CEUS are complementary to each other in classifying malignant liver nodules. The use of the combined imaging modalities shows clinical value for characterizing small liver nodules and predicting the degree of malignancy.

Linkage of angiotensinogen gene polymorphisms with hypertension in a sibling study of Hong Kong Chinese.

OBJECTIVE: The angiotensinogen gene has been linked with human essential hypertension in whites but the relationship in Asian populations has been less consistent. This study aimed to examine genetic associations between hypertension and the M235T, T174M, and G-217A polymorphisms of the angiotensinogen gene in Chinese siblings. METHODS: We studied members of 126 families with a hypertensive proband, including 434 siblings, of which 178 were hypertensive. Parental history of hypertension was recorded. The M235T, T174M, and G-217A polymorphisms were examined using a microarray method, validated by sequencing. The transmission disequilibrium test was applied to identify whether the genetic polymorphism loci were related to hypertension. Haplotype analysis of the combined polymorphisms was applied using the TRANSMIT program. Linkage study was conducted by applying the affected pedigree member method. RESULTS: A significant overtransmission was observed for the T235 allele at the M235T polymorphism and hypertension (chi2 = 4.41, P = 0.036) but not for the T174M and G-217A polymorphisms. The haplotype analysis showed a significant association with the haplotypes of paired markers (T174 and T235) with chi2 value of 8.131 (P = 0.004; global test chi2 = 9.131, P = 0.028). Linkage between M235T and hypertension was detected (T = -2.25, P = 0.019), and a tendency for linkage with central obesity-related hypertension was found for the M235T and T174M polymorphisms (P = 0.0087 and P = 0.01). CONCLUSION: The M235T and T174M variants, especially the T235 allele, contribute to an increased risk of hypertension in these Chinese patients.

How well do HapMap haplotypes identify common haplotypes of genes? A comparison with haplotypes of 334 genes resequenced in the environmental genome project.

One of the goals of the International HapMap Project is the identification of common haplotypes in genes. However, HapMap uses an incomplete catalogue of single nucleotide polymorphisms (SNPs) and might miss some common haplotypes. We examined this issue using data from the Environmental Genome Project (EGP) which resequenced 335 genes in 90 people, and thus, has a nearly complete catalogue of gene SNPs. The EGP identified a total of 45,243 SNPs, of which 10,780 were common SNPs (minor allele frequency >or=0.1). Using EGP common SNP genotype data, we identified 1,459 haplotypes with frequency >or=0.05 and we use these as "benchmark" haplotypes. HapMap release 16 had genotype information for 1,573 of 10,780 (15%) EGP common SNPs. Using these SNPs, we identified common HapMap haplotypes (frequency >or=0.05) in each of the four HapMap ethnic groups. To compare common HapMap haplotypes to EGP benchmark haplotypes, we collapsed benchmark haplotypes to the set of 1,573 SNPs. Ninety-eight percent of the collapsed benchmark haplotypes could be found as common HapMap haplotypes in one or more of the four HapMap ethnic groups. However, collapsing benchmark haplotypes to the set of SNPs available in HapMap resulted in a loss of haplotype information: 545 of 1,459 (37%) benchmark haplotypes were uniquely identified, and only 25% of genes had all their benchmark haplotypes uniquely identified. We resampled the EGP data to examine the effect of increasing the number of HapMap SNPs to 5 million, and estimate that approximately 40% of common SNPs in genes will be sampled and that half of the genes will have sufficient SNPs to identify all common haplotypes. This inability to distinguish common haplotypes of genes may result in loss of power when examining haplotype-disease association.

An affected pedigree member analysis of linkage between the dopamine D2 receptor gene TaqI polymorphism and obesity and hypertension.

BACKGROUND: Dopamine modulates a variety of physiological functions including natriuresis and satiety. We have previously reported that the TaqI polymorphism of the dopamine D2 receptor (DD2R) gene is associated with both blood pressure and obesity indices in a normoglycaemic Hong Kong Chinese population. In this study, we present evidence confirming the linkage between this gene polymorphism, obesity and hypertension. METHODS: Two hundred and seventy-four siblings from 96 normoglycaemic hypertensive families were recruited, including 133 who were hypertensive. Central obesity was defined as a waist-to-hip ratio of > or = 0.9 and > or = 0.85 in males and females, respectively, and was identified in 99 of the siblings. The DD2R gene TaqI polymorphism was identified with a polymerase chain reaction based restriction fragment length polymorphism protocol. The affected pedigree member (APM) linkage analysis (sib-pair program, version 0.99.9, by D.L. Duffy) was used to assess for linkage between this gene polymorphism, obesity and hypertension in 73 families with siblings discordant for hypertension. RESULTS: The A1 allele frequencies were similar in the 133 hypertensive, and 141 normotensive siblings, including the 99 centrally obese siblings at 0.431, 0.421 and 0.418, respectively. APM linkage analysis suggested that the DD2R gene TaqI polymorphism had evidence of linkage with blood pressure (T = -1.86, P = 0.013), as well as with obesity (T = -1.58, P = 0.007). CONCLUSION: Our data in normoglycaemic Hong Kong Chinese supports that the DD2R gene TaqI polymorphism is a marker associated with the pathogenesis of obesity and hypertension.

Familial risk and clustering of nasopharyngeal carcinoma in Guangdong, China.

BACKGROUND: Previous studies have suggested that genetic susceptibility may play an important role in the etiology of nasopharyngeal cancer (NPC). However, to date, few large-scale studies have been conducted on familial risk and clustering of NPC in a high-risk area of China. METHODS: In the current study, 2252 patients with NPC who were treated at the Cancer Center of Sun Yat-Sen University in Guangdong Province, China, were identified as probands. Family histories of NPC and other malignancies were observed in first-degree relatives (FDRs) and second-degree relatives, and other information was obtained through interviews. One thousand nine hundred and three Cantonese families were selected for further investigation. To assess familial aggregation, the authors used standardized incidence ratios (SIRs) to measure the risk of NPC for FDRs and compared the observed number of cases with the number predicted by population-based frequencies in the Cantonese population of Hong Kong. RESULTS: The current analysis indicated that families with > or = 3 relatives who had NPC were distributed predominantly among a high-risk subgroup of the Cantonese population in Guangdong Province and that the frequency of these families was 0.68%. An SIR of 2.09 (95% confidence interval [CI], 1.80-2.40) was observed among 13,833 FDRs in the high-risk subgroup, and a significantly elevated risk for NPC was observed in FDRs of probands with early age of onset (age < 40 years; SIR, 9.01 [95% CI, 6.10-13.30]). Furthermore, decreased risks of hepatic, lung, esophageal, gastric, and breast carcinoma, as well as malignancy of all sites, were observed among FDRs of probands with NPC when Hong Kong and Shanghai populations were used as reference groups. CONCLUSIONS: NPC tends to aggregate in Cantonese families in Guangdong Province, and the malignancies in these families appear to be site specific, with no excess of any other malignancy.

[Epidemiological study of nasopharyngeal carcinoma risk in relatives of high-risk families in Guangdong].

BACKGROUND & OBJECTIVE: Familial clustering of NPC has been widely observed, however, related investigations were mainly involved in individual reports for high-risk families or case-control study with small sample size, so no quantitive evaluation for NPC risk in relatives of high-risk families documented in high-risk area until now. The purpose of the study was to estimate NPC risk among relatives of high-risk pedigrees in Guangong province, so as to provide information for genetic epidemiology and clinical genetic consultation. METHODS: One hundred and thirteen high-risk pedigrees were collected in the Cancer Center of Sun Yat-sen University, and standardized incidence ratio (SIR) was used to estimate NPC risk of first degree relatives (FDR). RESULTS: NPC risk was significantly higher in first degree relatives that in general population, and SIR was 37.55; in addition, SIRs were 50.72, 79.64, 7.12, and 33.58 in their brothers, sisters, fathers, and mothers respectively. CONCLUSION: NPC risk of relatives in familial NPC pedigrees elevates 7.12 to 79.64 times in high-risk families.