Sandra L. Starnes

Identification of somatic mutations in non-small cell lung carcinomas using whole-exome sequencing

Lung cancer is the leading cause of cancer-related death, with non-small cell lung cancer (NSCLC) being the predominant form of the disease. Most lung cancer is caused by the accumulation of genomic alterations due to tobacco exposure. To uncover its mutational landscape, we performed whole-exome sequencing in 31 NSCLCs and their matched normal tissue samples. We identified both common and unique mutation spectra and pathway activation in lung adenocarcinomas and squamous cell carcinomas, two major histologies in NSCLC. In addition to identifying previously known lung cancer genes (TP53, KRAS, EGFR, CDKN2A and RB1), the analysis revealed many genes not previously implicated in this malignancy. Notably, a novel gene CSMD3 was identified as the second most frequently mutated gene (next to TP53) in lung cancer. We further demonstrated that loss of CSMD3 results in increased proliferation of airway epithelial cells. The study provides unprecedented insights into mutational processes, cellular pathways and gene networks associated with lung cancer. Of potential immediate clinical relevance, several highly mutated genes identified in our study are promising druggable targets in cancer therapy including ALK, CTNNA3, DCC, MLL3, PCDHIIX, PIK3C2B, PIK3CG and ROCK2.

Noninvasive evaluation of hand circulation before radial artery harvest for coronary artery bypass grafting

OBJECTIVE Radial artery harvesting for coronary artery bypass may lead to digit ischemia if collateral hand circulation is inadequate. The modified Allens test is the most common preoperative screening test used. Unfortunately, this test has high false-positive and false-negative rates. The purpose of this study was to compare the results of a modified Allens test with digit pressure change during radial artery compression for assessing collateral circulation before radial artery harvest. METHODS One hundred twenty-nine consecutive patients were studied before coronary artery bypass operations. A modified Allens test was performed with Doppler ultrasound to assess blood flow in the superficial palmar arch before and during radial artery compression. A decreased audible Doppler signal after radial artery compression was considered a positive modified Allens test. First and second digit pressures were measured before and during radial artery compression. A decrease in digit pressure of 40 mm Hg or more (digit DeltaP) with radial artery compression was considered positive. RESULTS Seven of 14 dominant extremities (50%) and 8 of the 16 nondominant extremities (50%) with a positive modified Allens test had a digit DeltaP of less than 40 mm Hg (false positive). Sixteen of 115 dominant extremities (14%) and 5 of 112 nondominant extremities (4%) with a negative Allens test had a digit DeltaP of 40 mm Hg or more with radial artery compression (false negative). CONCLUSION Use of the modified Allens test for screening before radial artery harvest may unnecessarily exclude some patients from use of this conduit and may also place a number of patients at risk for digit ischemia from such harvest. Direct digit pressure measurement is a simple, objective method that may more precisely select patients for radial artery harvest. Additional studies are needed to define objective digital pressure criteria that will accurately predict patients at risk for hand ischemia after radial harvest.

Sustained CTL activation by murine pulmonary epithelial cells promotes the development of COPD-like disease

Chronic obstructive pulmonary disease (COPD) is a lethal progressive lung disease culminating in permanent airway obstruction and alveolar enlargement. Previous studies suggest CTL involvement in COPD progression; however, their precise role remains unknown. Here, we investigated whether the CTL activation receptor NK cell group 2D (NKG2D) contributes to the development of COPD. Using primary murine lung epithelium isolated from mice chronically exposed to cigarette smoke and cultured epithelial cells exposed to cigarette smoke extract in vitro, we demonstrated induced expression of the NKG2D ligand retinoic acid early transcript 1 (RAET1) as well as NKG2D-mediated cytotoxicity. Furthermore, a genetic model of inducible RAET1 expression on mouse pulmonary epithelial cells yielded a severe emphysematous phenotype characterized by epithelial apoptosis and increased CTL activation, which was reversed by blocking NKG2D activation. We also assessed whether NKG2D ligand expression corresponded with pulmonary disease in human patients by staining airway and peripheral lung tissues from never smokers, smokers with normal lung function, and current and former smokers with COPD. NKG2D ligand expression was independent of NKG2D receptor expression in COPD patients, demonstrating that ligand expression is the limiting factor in CTL activation. These results demonstrate that aberrant, persistent NKG2D ligand expression in the pulmonary epithelium contributes to the development of COPD pathologies.

Segmentectomy Versus Wedge Resection for Non-Small Cell Lung Cancer in High-Risk Operable Patients

BACKGROUND Patients with early-stage lung cancer and limited pulmonary reserve may not be appropriate candidates for lobectomy. In these situations, sublobar resection (wedge or segmentectomy) is generally performed. Many physicians believe that segmentectomy is superior because it allows for an improved parenchymal margin and nodal sampling. METHODS We performed an analysis using operative and pathology reports collected as part of planned data collection for American College of Surgeons Surgical Oncology Group (ACOSG) Z4032. This was a prospective trial in which patients with clinical stage I lung cancer and limited pulmonary function were randomized to sublobar resection with or without brachytherapy. The operative approach (video-assisted thoracic surgery [VATS] vs thoracotomy), extent of resection, and degree of lymph node evaluation were at the discretion of the individual surgeon. The primary aim of this analysis was to compare the parenchymal margin achieved between segmentectomy and wedge resection. Secondary aims included the extent of nodal staging and whether the operative approach (VATS vs open) had an effect on margin status and nodal evaluation. RESULTS Among 210 patients, 135 (64%) underwent a VATS approach and 75 (36%) a thoracotomy. A segmentectomy was performed in 57 patients (27%) and a wedge resection in 153 patients (73%). There were no significant differences in the degree of nodal upstaging, stations sampled, or parenchymal margin obtained between VATS and thoracotomy. However, significant differences were observed between patients who underwent a segmentectomy and those who underwent a wedge resection with regard to parenchymal margin (1.5 cm vs 0.8 cm, p = 0.0001), nodal upstaging (9% vs 1%, p = 0.006), and nodal stations sampled (3 vs 1, p < 0.0001) . Notably, 41% of patients treated by wedge resection had no nodes sampled at the time of operation compared with 2% of those who underwent segmentectomy (p < 0.0001). CONCLUSIONS In ACOSG Z4032, wedge resection, regardless of the approach, was associated with a smaller parenchymal margin and a lower yield of lymph nodes and rate of nodal upstaging when compared with segmentectomy.

Impact of brachytherapy on local recurrence rates after sublobar resection: results from ACOSOG Z4032 (Alliance), a phase III randomized trial for high-risk operable non-small-cell lung cancer.

PURPOSE A major concern with sublobar resection (SR) for non-small-cell lung cancer (NSCLC) is high local recurrence (LR). Adjuvant brachytherapy may reduce LR This multicenter randomized trial compares SR to SR with brachytherapy (SRB). PATIENTS AND METHODS High-risk operable patients with NSCLC ≤ 3 cm were randomly assigned to SR or SRB. The primary end point was time to LR, where LR included recurrence at the staple line (local progression), in the primary tumor lobe away from the staple line, and in ipsilateral hilar nodes. The trial was designed to have a 90% power to detect a hazard ratio (HR) of 0.315 in favor of SRB, using a one-sided type I error rate of 0.05 with a sample size of 100 eligible patients in each arm. RESULTS Two hundred twenty-four patients were randomly assigned; 222 patients were evaluable for intent-to-treat analysis. Median age was 71 years (range, 49 to 87 years). No differences were found in baseline characteristics. Median follow-up time was 4.38 years (range, 0.04 to 5.59 years). There was no difference in time to LR (HR, 1.01; 95% CI, 0.51 to 1.98; log-rank P = .98) or in the types of LR. Local progression occurred in only 17 (7.7%) of 222 patients. In patients with potentially compromised margins (margin < 1 cm, margin-to-tumor ratio < 1, positive staple line cytology, wedge resection, nodule size > 2.0 cm), SRB did not reduce LR, although trends favored the SRB arm. This was most marked in 14 patients with positive staple line cytology (HR, 0.22; P = .24). Three-year overall survival rates were similar for patients in the SR (71%) and SRB (71%) arms (P = .97). CONCLUSION Brachytherapy did not reduce LR after SR. This finding may have been related to closer attention to parenchymal margins by surgeons participating in this study.

Vascular endothelial growth factor and basic fibroblast growth factor in children with cyanotic congenital heart disease

OBJECTIVE Vascular endothelial growth factor and basic fibroblast growth factor are potent stimulators of angiogenesis. Children with cyanotic congenital heart disease often experience the development of widespread formation of collateral blood vessels, which may represent a form of abnormal angiogenesis. We undertook the present study to determine whether children with cyanotic congenital heart disease have elevated serum levels of vascular endothelial growth factor and basic fibroblast growth factor. METHODS Serum was obtained from 22 children with cyanotic congenital heart disease and 19 children with acyanotic heart disease during cardiac catheterization. Samples were taken from the superior vena cava, inferior vena cava, and a systemic artery. Vascular endothelial growth factor and basic fibroblast growth factor levels were measured in the serum from each of these sites by enzyme-linked immunosorbent assay. RESULTS Vascular endothelial growth factor was significantly elevated in the superior vena cava (P =.04) and systemic artery (P =.02) but not in the inferior vena cava (P =.2) of children with cyanotic congenital heart disease compared to children with acyanotic heart disease. The mean vascular endothelial growth factor level, determined by averaging the means of all 3 sites, was also significantly elevated (P =.03). Basic fibroblast growth factor was only significantly elevated in the systemic artery (P =.02). CONCLUSION Children with cyanotic congenital heart disease have elevated systemic levels of vascular endothelial growth factor. These findings suggest that the widespread formation of collateral vessels in these children may be mediated by vascular endothelial growth factor.

Predictors of conversion to thoracotomy for video-assisted thoracoscopic lobectomy: a retrospective analysis and the influence of computed tomography-based calcification assessment.

OBJECTIVE Conversion to an open thoracotomy during video-assisted thoracoscopic surgery lobectomy is reported to occur in up to 23% of cases and can be associated with increased morbidity. We developed a preoperative computed tomography calcification score based on anatomic location and extent of calcifications to evaluate the ability to predict video-assisted thoracoscopic surgery conversion. METHODS Patients undergoing planned video-assisted thoracoscopic surgery lobectomy between 2003 and 2009 were identified. Baseline demographics, comorbidities, operative data, and postoperative outcomes were reviewed. Preoperative chest computed tomography scans were examined by an attending thoracic surgeon. Calcifications were scored from 0 (none) to 6 (major hilar calcifications at the resection bronchus). Preoperative patient and tumor characteristics and the calcification score were analyzed for their ability to predict conversion. We then compared outcomes among patients undergoing video-assisted thoracoscopic surgery, converted video-assisted thoracoscopic surgery, and planned open thoracotomy. RESULTS Of the 193 patients undergoing planned video-assisted thoracoscopic surgery lobectomy, 148 (77%) had a completed video-assisted thoracoscopic surgery lobectomy, and 45 (23%) underwent conversion to thoracotomy. The calcification score was found to independently predict video-assisted thoracoscopic surgery conversion. Patients who were converted to a thoracotomy had significantly higher 30-day mortality, more atrial arrhythmias, increased blood loss, longer operative time, and increased length of stay compared with those who underwent completed video-assisted thoracoscopic surgery lobectomy and longer length of stay compared with those undergoing planned open lobectomy. CONCLUSIONS Calcification score based on the location and degree of calcifications can predict the increased likelihood of video-assisted thoracoscopic surgery conversion. This scoring system could be one element used to choose the approach for a lobectomy, especially during a surgeons learning curve.

The impact of adjuvant brachytherapy with sublobar resection on pulmonary function and dyspnea in high-risk patients with operable disease: preliminary results from the American College of Surgeons Oncology Group Z4032 trial.

BACKGROUND Z4032 was a randomized study conducted by the American College of Surgeons Oncology Group comparing sublobar resection alone versus sublobar resection with brachytherapy for high-risk operable patients with non-small cell lung cancer (NSCLC). This evaluates early impact of adjuvant brachytherapy on pulmonary function tests, dyspnea, and perioperative (30-day) respiratory complications in this impaired patient population. METHODS Eligible patients with stage I NSCLC tumors 3 cm or smaller were randomly allocated to undergo sublobar resection with (SRB group) or without (SR group) brachytherapy. Outcomes measured included the percentage predicted forced expiratory volume in 1 second (FEV1%), percentage predicted carbon monoxide diffusion capacity (DLCO%), and dyspnea score per the University of California San Diego Shortness of Breath Questionnaire. Pulmonary morbidity was assessed per the Common Terminology Criteria for Adverse Events version 3.0. Outcomes were measured at baseline and 3 months. A 10% change in pulmonary function test or 10-point change in dyspnea score was deemed clinically meaningful. RESULTS Z4032 permanently closed to patient accrual in January 2010 at 224 patients. At 3-month follow-up, pulmonary function data are currently available for 148 (74 SR and 74 SRB) patients described in this report. There were no differences in baseline characteristics between arms. In the SR arm, 9 patients (12%) reported grade 3 respiratory adverse events, compared with 12 (16%) in the SRB arm (P = .49). There was no significant change in percentage change in DLCO% or dyspnea score from baseline to 3 months within either arm. In the case of FEV1%, percentage change from baseline to 3 months was significant within the SR arm (P = .03), with patients reporting improvement in FEV1% at month 3. Multivariable regression analysis (adjusted for baseline values) showed no significant impact of treatment arm, tumor location (upper vs other lobe), or surgical approach (video-assisted thoracoscopic surgery vs thoracotomy) on 3-month FEV1%, DLCO%, and dyspnea score. There was no significant difference in incidence of clinically meaningful (10% pulmonary function or 10-point dyspnea score change) change between arms. Twenty-two percent of patients with lower-lobe tumors and 9% with upper-lobe tumors demonstrated 10% decline in FEV1% (odds ratio, 2.79; 95 confidence interval, 1.07-7.25; P = .04). CONCLUSIONS Adjuvant intraoperative brachytherapy in conjunction with sublobar resection did not significantly worsen pulmonary function or dyspnea at 3 months in a high-risk population with NSCLC, nor was it associated with increased perioperative pulmonary adverse events. Lower-lobe resection was the only factor significantly associated with clinically meaningful decline in FEV1%.

Analysis of longitudinal quality-of-life data in high-risk operable patients with lung cancer: Results from the ACOSOG Z4032 (Alliance) multicenter randomized trial

BACKGROUND Prior studies have suggested that low baseline quality-of-life (QOL) scores predict worse survival in patients undergoing lung cancer surgery. However, these studies involved average-risk patients undergoing lobectomy. We report QOL results from a multicenter trial, American College of Surgeons Oncology Group Z4032, which randomized high-risk operable patients to sublobar resection (SR), or SR with brachytherapy, and included longitudinal QOL assessments. METHODS Global QOL, using the 36-item Short-Form Health Survey (SF36), and the dyspnea score from the University of California, San Diego Shortness of Breath Questionnaire (SOBQ) scale, was measured at baseline, 3, 12, and 24 months. SF36 physical component summary (PCS) and mental component summary (MCS) scores were standardized and adjusted for age and gender normals, with scores <50 indicating below-average health status. SOBQ scores were transformed to a 0-100 (poor-excellent) scale. Aims were to: (1) determine the impact of baseline scores on recurrence-free survival, overall survival, and 30-day adverse events (AEs); and (2) identify subgroups (surgical approach, resection type. tumor location, tumor size, respiratory function) with a ≥ 10-point decline or improvement in QOL after SR. RESULTS Two hundred twelve eligible patients were included. There were no significant differences in baseline QOL scores between arms. Median baseline PCS, MCS, and SOBQ scores were 42.7, 51.1, and 70.8, respectively. There were no differences in grade-3+ AEs, overall survival, or recurrence-free survival in patients with baseline scores ≤ median versus > median values, except for a significantly worse overall survival for patients with baseline SOBQ scores ≤ median value. There were no significant differences between the study arms in percentage change of QOL scores from baseline to 3, 12, or 24 months. Further comparison combining the 2 arms demonstrated a higher percentage of patients with a ≥ 10-point decline in SOBQ scores with segmentectomy compared with wedge resection (40.5% vs 21.9%, P = .03) at 12 months, with thoracotomy versus video-assisted thoracic surgery (VATS) (38.8% vs 20.4%, P = .03) at 12 months, and T1b versus T1a tumors (46.9% vs 23.5%, P = .020) at 24 months. A ≥ 10-point improvement in PCS score was seen at 3 months with VATS versus thoracotomy (16.5% vs 3.6%, P = .02). CONCLUSIONS In high-risk operable patients, poor baseline QOL scores were not predictive for worse overall or recurrence-free survival, or for higher risk for AEs following SR. VATS was associated with improvement in physical function at 3 months, and improved dyspnea scores at 12 months, lending support for the preferential use of VATS when SR is undertaken.

Thoracoscopic lobectomy: Introduction of a new technique into a thoracic surgery training program

OBJECTIVE Thoracoscopic lobectomy has been demonstrated to be safe and oncologically sound. However, few thoracic surgeons perform the operation. We hypothesized that use of a predetermined, stepwise plan for introduction of thoracoscopic lobectomy into a thoracic surgical training program would facilitate safe learning of the technique. METHODS Databases from 2 affiliated institutions were queried to identify all lobectomies during a 4-year period. Our model for introduction of thoracoscopic lobectomy was established expertise in open lobectomy and video-assisted thoracoscopic surgery, participation in a formal thoracoscopic lobectomy course, stepwise introduction of specific techniques used in thoracoscopic lobectomy into the operative approach, proctoring of initial thoracoscopic lobectomies by partners, and teaching of the technique to other thoracic surgeons and residents. RESULTS We performed 202 lobectomies: 97 open and 105 thoracoscopic. Mortality was 3.0%. The conversion rate from thoracoscopic to open thoracotomy was 13%. When divided into quartiles, the percentage of lobectomies performed thoracoscopically increased from 18% in the first quartile to 82% in the fourth quartile. With ongoing experience, the procedure was performed at higher frequency by new staff and trainees. Residents performed 0% of thoracoscopic lobectomies in the first quartile, increasing to 54% in the third quartile. In the fourth quartile residents and a new staff surgeon performed 76% of thoracoscopic lobectomies. A resident was the operating surgeon for 37 thoracoscopic lobectomies. CONCLUSIONS Introduction of thoracoscopic lobectomy into an academic thoracic surgical practice can be achieved safely if a stepwise transition is invoked. Training of thoracic surgical residents and additional staff can thus be effectively accomplished.