Somchareon Saeteng

Effect of combined genetic polymorphisms on lung cancer risk in northern Thai women

Lung cancer is a major cause of cancer-related death in developed countries, and its incidence in developing countries is increasing. In Thailand, cancer incidences differ greatly from region to region, and lung cancer is the most common cancer in the northern Thai population. The polymorphic frequency of 10 genetic susceptibility genes and their association with lung cancer were examined in a northern Thai population: CYP1A1 (MspI), CYP1A1 (Ile462Val), CYP2E1 (PstI), CYP2E1 (DraI), GSTM1, GSTT1, MPO (AciI), OGG1 (Ser326Cys), TP53 (Arg72Pro), and MMP1(AluI). The 173 subjects were 91 lung cancer patients and 82 healthy volunteers. Although no significant association between any single genetic variant and lung cancer risk was observed, when genetic variants were analyzed in combination, a significant effect on lung cancer risk was found for the variant allele in a combination of five genes involved in oxidative stress and inflammatory response: GSTM1 (null), MPO (-463A), OGG1 (326Cys), TP53 (72Pro) (alias p53), MMP1 (2G). With a reference group of individuals carrying at least two wild-type genotypes of these five genes, it was found that an individual carrying three or more variant genotypes is at significantly higher risk of developing lung cancer with the increasing of odds ratios (OR) in concurrence with the number of variant genes. The OR was 2.41 (95% CI = 0.76-7.64), 3.90 (95% CI = 1.23-12.34), and 5.20 (95% CI = 1.31-20.54) for individuals carrying three, four, and five variants, respectively. After stratifying by sex, the OR was higher for women: OR 4.05 (95% CI = 0.44-36.94), 9.00 (95% CI = 0.95-84.89) and 18.00 (95% CI = 1.49-216.62) for three, four, and five variant genotypes, respectively. This augmented effect on lung cancer risk of variant genes involved in oxidative stress and inflammatory response in women with a low prevalence of smoking indicates their modifying effect on other risk factors, such as environmental cigarette smoke, air pollution, radon radiation, or infection of the airway. Confirmation would require further investigations with larger sample sizes.

Incidence of and Risk Factors for Cardiovascular Complications After Thoracic Surgery for Noncancerous Lesions

OBJECTIVE The purpose of this study was to determine the incidence of and risk factors for cardiovascular complications after thoracic surgery for noncancerous lesions. DESIGN Retrospective cohort study. SETTING A tertiary medical center. PARTICIPANTS All consecutive patients undergoing either thoracotomy or thoracoscopy for noncancerous lesions between 2005 and 2011 were included. MEASUREMENTS AND MAIN RESULTS The primary outcomes were the incidence and types of cardiovascular complications such as cardiac arrhythmias, cardiac arrest, heart failure, and myocardial ischemia during hospitalization. A total of 719 patients were recruited, 60% of whom had infections. The incidence of cardiovascular complications after thoracic surgery was 6.7% (48 of 719), of which cardiac arrhythmia was the most common (25 of 48, 52%). The multivariate risk regression analysis showed that age>55 years (risk ratio [RR]=4.0; 95% confidence interval [CI]=2.1-7.5; p<0.01), diabetes mellitus (RR=3.0; 95% CI=1.7-5.3; p<0.01), coronary artery disease (RR=4.8; 95% CI=2.3-10.2; p<0.01), duration of surgery>180 minutes (RR=2.6; 95% CI=1.3-5.1; p<0.01), intraoperative hypotension (RR=2.6; 95% CI=1.6-4.3; p<0.01), and positive fluid balance>2,000 mL (RR=2.5; 95% CI=1.4-4.5; p<0.01) were independent risk factors for cardiovascular complications. CONCLUSIONS Knowledge of risk factors could help surgical teams to identify high risk patients and adjust modifiable risk factors including optimization of medical conditions, correction of intraoperative hypotension, and appropriate blood and fluid administration in order to reduce perioperative morbidity and mortality.

Association of positive fluid balance and cardiovascular complications after thoracotomy for noncancer lesions

Objective The purpose of this study was to explore the influence of positive fluid balance on cardiovascular complications after thoracotomy for noncancer lesions. Methods After approval from an institutional review board, a retrospective cohort study was conducted. All consecutive patients undergoing thoracotomy between January 1, 2005 and December 31, 2011 in a single medical center were recruited. The primary outcome of the study was the incidence of cardiovascular complications, which were defined as cardiac arrhythmia, cardiac arrest, heart failure, myocardial ischemia, and pulmonary embolism. Univariable and multivariable risk regression analyses were used to evaluate the association between positive fluid balance and cardiovascular complications. Results A total of 720 patients were included in this study. The incidence of cardiovascular complications after thoracotomy for noncancer lesions was 6.7% (48 of 720). Patients with positive fluid balance >2,000 mL had a significantly higher incidence of cardiovascular complications than those with positive fluid balance ≤2,000 mL (22.2% versus 7.0%, P=0.005). Cardiac arrhythmias were the most common complication. Univariable risk regression showed that positive fluid balance >2,000 mL was a significant risk factor (risk ratio =3.15, 95% confident interval [CI] =1.44–6.90, P-value =0.004). After adjustment for all potential confounding variables during multivariable risk regression analysis, positive fluid balance >2,000 mL remained a strong risk factor for cardiovascular complications (risk ratio =2.18, 95% CI =1.36–3.51, P-value =0.001). Causes of positive fluid balance >2,000 mL included excessive hemorrhage (48%), hypotension without excessive hemorrhage (29.6%), and liberal fluid administration (22.4%). Conclusion Positive fluid balance was a significant risk factor for cardiovascular complications. Strategies to minimize positive fluid balance during surgery for patients at high risk of cardiovascular complications include preparing adequate blood and blood products, considering appropriate hemoglobin level as a transfusion trigger, and adjusting the optimal dose of local anesthetic for intraoperative thoracic epidural analgesia.

P2.15-28 Effect of Insurance Types on Tumor Recurrence and Overall Survival in Resectable Non-Small Lung Cancer Patients in Northern Thailand

Background: High-precision three-dimensional (3D) image analysis system has been used for preoperative planning in various fields including thoracic surgery. Such software has made us quite easy to measure lung volume. Change of pulmonary function after surgery has been surveyed in some reports, but there are few reports about lung volume change after surgery. Method: We conducted a retrospective review of 49 patients who underwent lobectomy between January 2014 and June 2016 at General Hospital of Japan Railway Company. We used 3D image analysis system (SYNAPSE VINCENT, Fujifilm Corp, Tokyo, Japan) to calculate lung volume of each patient from computed tomography (CT) images which were taken twice, before surgery and 6 months after surgery. We estimated lung volume change from the difference between those two values. Result: There were 19 right upper lobectomies (RUL), 7 right middle lobectomies (RML), 8 right lower lobectomies (RLL), 5 left upper lobectomies (LUL), and 10 left lower lobectomies (LLL). We performed lobectomies in three different surgical approaches; Thoracotomy (n1⁄45), Hybrid Video-assisted thoracic surgery (VATS) (n1⁄424), Complete VATS (n1⁄420). 7 patients needed pleurodesis after surgery to treat air leakage. The average of total lung volume change was -10.4%. Right lobectomies showed 11.45% decrease of lung volume in average, while left lobectomies showed 5.34% decrease (p1⁄40.18). Decrease ratio seemed to depend on the way of approaches; Thoracotomy was -19.98% and VATS (hybrid and complete) was -8.58% (p1⁄40.12). Volume change of patients who underwent pleurodesis after surgery was -20.37%, while the ratio of the others was -7.84% (p1⁄40.03). Conclusion: VATS seemed to be better in the point of lung volume after lobectomy than thoracotomy. Pleurodesis turned out to reduce lung volume significantly. For furthur study, we will compare lung volume with pulmonary function on a lager aomount of data.