Wee Teng Poh

Polymorphisms in inflammatory pathway genes, host factors and lung cancer risk in Chinese female never-smokers.

Inflammation appears to be important in lung carcinogenesis among smokers, but its role among never-smokers is not well established. We hypothesized that inflammatory medical conditions and gene polymorphisms interact to increase lung cancer risk in never-smokers. We interviewed 433 Singaporean female never-smoker lung cancer patients and 1375 hospital controls, and evaluated six polymorphisms in the interleukin 1-β, interleukin 6 (IL6), cyclooxygenase-2, peroxisome proliferator-activated receptor-γ and interleukin 1-β receptor antagonist (IL1RN) genes. Tuberculosis was associated with a non-significant elevated risk of lung cancer [odds ratio (OR) 1.58, 95% confidence interval (CI) 0.95-2.62]. There was no effect of asthma, atopy or chronic productive cough individually. However, the presence of one or more of these conditions (asthma, cough or atopy) increased risk (OR 2.24, 95%CI 1.15-4.38) in individuals possessing the T/T genotype at interleukin 1-β -31T/C, but not in those possessing the C/T (OR 0.87, 95%CI 0.51-1.57) or C/C genotypes (OR 0.58, 95%CI 0.27-1.27), and in individuals having the *2 variable number of tandem repeat allele of IL1RN [OR 5.09 (1.39-18.67)], but not in those without (OR 0.93, 95%CI 0.63-1.35). The IL6-634 G allele increased the risk of lung cancer (OR 1.44, 95%CI 1.07-1.94). Lung cancer risk also increased with the number of polymorphism sites where at least 1 risk allele was present [interleukin 1-β -31T/C (T allele), IL1RN (*2 allele) and IL6-634C/G (G allele)] among those with asthma, cough or atopy (Ptrend 0.001) but not in those without (Ptrend 0.47). Our results suggest that the effect of inflammatory medical conditions on lung cancer in never-smokers is modulated by host genetic susceptibility and will need to be confirmed in other studies conducted in similar populations.

Female Reproductive Factors, Gene Polymorphisms in the Estrogen Metabolism Pathway, and Risk of Lung Cancer in Chinese Women

The authors examined relations between reproductive factors and 5 estrogen pathway gene polymorphisms (CYP17 rs743572, CYP19A1 rs10046, ERβ rs1256049, ERβ rs4986938, and COMT rs4680) among 702 Singapore Chinese female lung cancer cases and 1,578 hospital controls, of whom 433 cases (61.7%) and 1,375 controls (87.1%) were never smokers. Parity (per child, odds ratio (OR) = 0.92, 95% confidence interval (CI): 0.87, 0.97) and menstrual cycle length (for ≥30 days vs. <30 days, OR = 0.50, 95% CI: 0.32, 0.80) were inversely associated with lung cancer in never smokers, while age at first birth (for ages 21-25, 26-30, and ≥31 years vs. ≤20 years, ORs were 1.54, 2.17, and 1.30, respectively), age at menopause (for ages 49-51 and ≥52 years vs. ≤48 years, ORs were 1.37 and 1.59; P(trend) = 0.003), and reproductive period (for 31-33, 34-36, 37-39, and ≥40 years vs. ≤30 years, ORs were 1.06, 1.25, 1.45, and 1.47; P(trend) = 0.026) were positively associated. Among smokers, parity was inversely associated with lung cancer, but there was no association with other reproductive factors. The COMT rs4680 A allele was positively associated with lung cancer in never smokers (for G/A or A/A vs. G/G, OR = 1.46, 95% CI: 1.12, 1.90) but not in ever smokers. No associations were seen with other polymorphisms. These results support a risk-enhancing role of estrogens in lung carcinogenesis among never smokers.

Meat Consumption and Risk of Lung Cancer Among Never-Smoking Women

The relationship between diet and lung cancer, apart from the protective effect of fruit and vegetables, is poorly understood. Reports on the role of dietary components such as meat are inconsistent, and few studies include sufficient numbers of nonsmokers. We examined the relationship between meat consumption and never-smoking lung cancer in a hospital-based case–control study of Singapore Chinese women, a population with low smoking prevalence. Three hundred and ninety-nine cases and 815 controls were recruited, of whom 258 cases and 712 controls were never smokers. A standardized questionnaire (which included a food frequency questionnaire module) was administered by trained interviewers. Among these never smokers, fruit and vegetable intake were inversely associated with lung cancer risk. Seventy-two percent of meat consumed was white meat (chicken or fish). Meat consumption overall was inversely associated with lung cancer [adjusted odds ratio (OR), 0.88, 0.59 for second, third tertiles, P trend = .012]. An inverse relationship between fish consumption and lung cancer (adjusted OR, 0.81, 0.47 for 2nd, 3rd tertiles, P trend < .001) was observed. No association was seen between consumption of processed meats and lung cancer, nor between dietary heterocyclic amines and lung cancer. Our data suggest that fish consumption may be protective against lung cancer in never smokers.

Aspirin and non-aspirin non-steroidal anti-inflammatory drug use and risk of lung cancer

There is evidence that aspirin and non-aspirin non-steroidal anti-inflammatory drug (NSAID) have anti-carcinogenic properties, but their effect on lung cancer, in particular in never-smokers, is unclear. Information on past or current use of anti-inflammatory medication was obtained in 398 Chinese female primary lung cancer cases and 814 controls in a hospital-based study in Singapore. 65% of cases and 88% of controls were never-smokers. Controls were excluded if they had been admitted for conditions associated with aspirin or NSAID use (n=174). Regular aspirin use (twice a week or more, for a month or more) was associated with a reduced risk of lung cancer (adjusted odds ratio [OR] 0.50, 95% confidence intervals [95%CI] 0.31-0.81 in non-smokers; OR 0.38, 95%CI 0.16-0.93 in smokers). Regular use of non-aspirin NSAID, paracetamol, steroid creams and steroid pills was uncommon and no association with lung cancer was detected. Our results suggest that aspirin consumption may reduce lung cancer risk in Asian women and are consistent with current understanding of the role of cyclooxygenase in lung carcinogenesis.

Diagnosis of virus infection in orchid plants with high-resolution optical coherence tomography.

This work investigates the use of optical coherence tomography (OCT) to identify virus infection in orchid plants. Besides revealing the cross-sectional structure of orchid leaves, highly scattering upper leaf epidermides are detected with OCT for virus-infected plants. This distinct feature is not observable under histological examination of the leaf samples. Furthermore, the leaf epidermides of stressed but healthy plants, which exhibit similar visual symptoms as virus-infected plants, are not highly scattering and are similar to those of healthy plants. The results suggest that virus-infected orchid plants can be accurately identified by imaging the epidermal layers of their leaves with OCT. The OCT modality is suitable for fast, nondestructive diagnosis of orchid virus infection, which may potentially lead to significant cost savings and better control of the spread of viruses in the orchid industry.

Metachronous cholangiocarcinoma 13 years post resection of choledochal cyst—is long-term follow-up useful?: a case study and review of the literature

BackgroundPatients with congenital choledochal cyst are at risk of the development of hepatobiliary malignancy, with recommended treatment of choledochal cyst being surgical excision. The development of cholangiocarcinoma more than 10xa0years after excision of choledochal cysts is rare, with less than 21 cases reported in the literature from 1972 to 2014. This is the first reported case of metachronous recurrence after a previously excised adenocarcinoma within a choledochal cyst.Case presentationHerein, we review the case of a patient with cholangiocarcinoma arising 13xa0years post excision of a Todani type 1 choledochal cyst and discuss the theories of carcinogenesis and long-term management of patients with choledochal cysts. The long-term development of a malignancy must be considered in these patients.ConclusionsReviewing all published cases to date, regular follow-up post resection did not improve on the resectability and long-term survival of these patients. Patients presenting with symptoms did not prejudice against resectability. Despite curative resection, median survival was dismal. Optimal long-term follow-up strategies for these patients remain to be elucidated.

Solitary necrotic nodule of the liver: radiologic-pathologic correlation in a case with unusual imaging features.

Solitary necrotic nodule of the liver (SNNL) is rare. Generally thought to be nonmalignant, it is often mistaken for malignancy based on imaging findings alone. We present a case of a hepatitis B carrier who was found to have a new sonographically detected hepatic lesion. The lesion was further evaluated with CT and MRI, and as appearances were suggestive of a hypovascular hepatoma, the lesion was surgically resected. This case is unique in that while it demonstrates several characteristic features of SNNL, several other imaging and histological features have not been previously described.

Eosinophilic cholangiopathy: the diagnostic dilemma of a recurrent biliary stricture. Should surgery be offered for all?

A 63-year-old man presented with the initial diagnosis of autoimmune pancreatitis with obstructive jaundice. CT of the abdomen revealed an oedematous pancreas and dilated common bile duct (CBD), without gallstones. After failure of initial retrograde cholangiopancreatography, a percutaneous biliary catheter was inserted with good drainage. Subsequent endoscopic retrograde cholangiopancreatography (ERCP) revealed a 2u2005cm distal CBD stricture. A biliary stent was inserted past the stricture. Biopsy of the stricture, brush cytology of the bile duct and fine needle aspiration of pancreatic head under endoscopic ultrasound guidance were negative for malignancy. Autoimmune screen was negative as well. However, the patient represented with cholangitis requiring repeat ERCP and insertion of a second biliary stent. He finally underwent cholecystectomy with excision of the distal CBD and Roux-En-Y hepaticojejunostomy. Histology revealed diffuse eosinophilic cholecystitis and cholangitis. A retrospective review of the blood results showed persistent eosinophilia in full blood count measurements from presentation and persisting throughout the treatment period.

An unusual case of recurrent hepatocellular carcinoma presenting as an indeterminate right intrahepatic duct stricture

A 46-year-old man with segment 8 hepatocellular carcinoma (HCC) from hepatitis C-related, Child–Pugh class A cirrhosis underwent successful hepatic resection. This was complicated by a postoperative bilioma that was treated by percutaneous drainage. He presented again 6 months later with abdominal pain and cholestasis. Computed tomography (CT) of the liver showed no tumor recurrence. Magnetic resonance imaging (MRI) showed postcholecystectomy status, a mildly dilated common bile duct, non-visualization of the central right intrahepatic duct, a focal defect in the left intrahepatic duct, and proximal dilatation of both intrahepatic ducts (● Fig.1). Cholangioscopy using the SpyGlass DS Direct Visualization System (Boston Scientific, Natick, Massachusetts, USA) was performed. Blood clots were visualized in the left intrahepatic duct. A friable mass was visualized in the right intrahepatic duct (● Fig.2) and was biopsied (● Video 1). Bilateral stenting was performed. Histology revealed recurrent HCC (● Fig.3). HCC recurrence tends to present as a mass, so patients routinely undergo surveillance CT or MRI scans at scheduled intervals [1]. Uncommonly intraluminal biliary obstruction may arise postoperatively because of hemobilia, migration of tumor debris, or a tumor mass with continuous growth along the biliary tree [2]. In this case, the only positive finding was the MRI scan that demonstrated an indeterminate stricture with no mass. The first-generation Spyglass cholangioscopy system, which uses a fiber-optic probe, has been shown to be useful in determining the nature of indeterminate biliary strictures [3]. A systemic review demonstrated that the pooled sensitivity and specificity of cholangioscopy with targeted biopsies for the detection of cholangiocarcinoma were 66.2% and 97.0%, respectively [4]. The second-generation digital Spyglass system has much better cholangioscopic image resolution, thereby facilitating endoscopic diagnosis and targeted biopsies. In this case, it was used to diagnose recurrent HCC with a rare presentation of isolated intrahepatic bile duct stricture with no associated liver parenchymal lesion.

Foreign Material in Histological Specimens from Living Intravenous Drug Abusers (IVDA) — Illustration of 3 Cases

Drug addicts using the injection mode for drug delivery often suffer from complications relating to non-sterile needle pricks besides unintentional effects of the drugs such as anaphylaxis and other organ damage. Non-sterile injections lead to infections of all kinds, most common being viral such as Hepatitis B & C and HIV infections; besides the usual bacterial and fungal infections. The evidence for this habit however, resides in the inert fillers they inject into their bodies together with the drug. Particles phagocytosed by macrophages in the body constitute permanent evidence of their past demeanor. The present write-up serves to illustrate the presence of injected crystalline material in various organs/tissues of 3 living subjects as seen at routine diagnostic histology in a regional acute hospital. The findings at autopsies of those who die from illicit drug abuse are well documented in the forensic literature1.