Efficacy and safety of the Spiration Valve System™ for the treatment of severe emphysema in patients with Alpha-1 antitrypsin deficiency (EMPROVE)

OBJECTIVES

Alpha-1 antitrypsin deficiency (AATD) is a hereditary condition associated with emphysema. This study analyzed the efficacy and safety of Spiration Valve System TM (SVS) among AATD patients with severe emphysema.

METHODS

This multicenter prospective study included 20 patients demonstrating AATD as assessed by quantitative levels of AAT and genotype containing two ZZ alleles. Most diseased lobe based on high resolution computed tomography was selected for treatment with endobronchial SVS. The change from baseline in forced expiratory volume in 1 s (FEV1) at 6 months (Primary outcome) and at 12 months, quality-of-life (QoL) measured by St. George's Respiratory Questionnaire (SGRQ) as health status, dyspnea scale measured by mMRC, Chronic obstructive pulmonary disease (COPD) Assessment Test (CAT), 36-item Short Form Health Survey (SF-36) physical component summary (PCS) and safety were assessed.

RESULTS

Lung function (FEV1) significantly improved at 6 months (P = 0.02); but did not reach statistical significance at 12 months (P = 0.22). Significant improvement was observed in dyspnea (at all time points), QoL measures (3, 6, and 12 months), CAT score and PCS of SF-36 (1, 3 and 6 months). Response rates based on minimal clinically important difference reached 50-80% for all variables. Overall, 4.4 valves/patient were used to isolate the target lobe, with a mean procedure time of 20.3 min. Serious adverse events included COPD exacerbations (5%), pneumonia (10%), pneumothorax (15%) and death (5%), occurring within first three months.

CONCLUSION

SVS endobronchial valve treatment showed improvement in lung function, dyspnea, and QoL in AATD patients with severe emphysema.

Sustained Clinical Benefits of Spiration Valve System in Patients with Severe Emphysema: 24-Month Follow-Up of EMPROVE

Rationale: Follow-up of patients with emphysema treated with endobronchial valves is limited to 3-12 months after treatment in prior reports. To date, no comparative data exist between treatment and control subjects with a longer follow-up. Objectives: To assess the durability of the Spiration Valve System (SVS) in patients with severe heterogeneous emphysema over a 24-month period. Methods: EMPROVE, a multicenter randomized controlled trial, presents a rigorous comparison between treatment and control groups for up to 24 months. Lung function, respiratory symptoms, and quality-of-life (QOL) measures were assessed. Results: A significant improvement in forced expiratory volume in 1 second was maintained at 24 months in the SVS treatment group versus the control group. Similarly, significant improvements were maintained in several QOL measures, including the St. George's Respiratory Questionnaire and the COPD Assessment Test. Patients in the SVS treatment group experienced significantly less dyspnea than those in the control group, as indicated by the modified Medical Research Council dyspnea scale score. Adverse events at 24 months did not significantly differ between the SVS treatment and control groups. Acute chronic obstructive pulmonary disease exacerbation rates in the SVS treatment and control groups were 13.7% (14 of 102) and 15.6% (7 of 45), respectively. Pneumothorax rates in the SVS treatment and control groups were 1.0% (1 of 102) and 0.0% (0 of 45), respectively. Conclusions: SVS treatment resulted in statistically significant and clinically meaningful durable improvements in lung function, respiratory symptoms, and QOL, as well as a statistically significant reduction in dyspnea, for at least 24 months while maintaining an acceptable safety profile. Clinical trial registered with www.clinicaltrials.gov (NCT01812447).

Pulmonary Open, Robotic, and Thoracoscopic Lobectomy (PORTaL) Study: Survival Analysis of 6646 Cases

OBJECTIVE

The aim of this study was to analyze overall survival (OS) of robotic-assisted lobectomy (RL), video-assisted thoracoscopic lobectomy (VATS), and open lobectomy (OL) performed by experienced thoracic surgeons across multiple institutions.

SUMMARY BACKGROUND DATA

Surgeons have increasingly adopted RL for resection of early-stage lung cancer. Comparative survival data following these approaches is largely from single-institution case series or administrative data sets.

METHODS

Retrospective data was collected from 21 institutions from 2013 to 2019. Consecutive cases performed for clinical stage IA-IIIA lung cancer were included. Induction therapy patients were excluded. The propensity-score method of inverse-probability of treatment weighting was used to balance baseline characteristics. OS was estimated using the Kaplan-Meier method. Multivariable Cox proportional hazard models were used to evaluate association among OS and relevant risk factors.

RESULTS

A total of 2789 RL, 2661 VATS, and 1196 OL cases were included. The unadjusted 5-year OS rate was highest for OL (84%) followed by RL (81%) and VATS (74%); P =0.008. Similar trends were also observed after inverse-probability of treatment weighting adjustment (RL 81%; VATS 73%, OL 85%, P =0.001). Multivariable Cox regression analyses revealed that OL and RL were associated with significantly higher OS compared with VATS (OL vs. VATS: hazard ratio=0.64, P <0.001 and RL vs. VATS: hazard ratio=0.79; P =0.007).

CONCLUSIONS

Our finding from this large multicenter study suggests that patients undergoing RL and OL have statistically similar OS, while the VATS group was associated with shorter OS. Further studies with longer follow-up are necessary to help evaluate these observations.

Outcomes after sublobar resection versus lobectomy in non-small cell carcinoma in situ

OBJECTIVE

Guidelines for treatment of non-small cell lung cancer identify patients with tumors ≤2 cm and pure carcinoma in situ histology as candidates for sublobar resection. Although the merits of lobectomy, sublobar resection, and lymphoid (LN) sampling, have been investigated in early-stage non-small cell lung cancer, evaluation of these modalities in patients with IS disease can provide meaningful clinical information. This study aims to compare these operations and their relationship with regional LN sampling in this population.

METHODS

The National Cancer Database was used to identify patients diagnosed with non-small cell lung cancer clinical Tis N0 M0 with a tumor size ≤2 cm from 2004 to 2017. The χ2 tests were used to examine subgroup differences by type of surgery. Kaplan-Meier method and Cox proportional hazard model were used to compare overall survival.

RESULTS

Of 707 patients, 56.7% (401 out of 707) underwent sublobar resection and 43.3% (306 out of 707) underwent lobectomy. There was no difference in 5-year overall survival in the sublobar resection group (85.1%) compared with the lobectomy group (88.9%; P = .341). Multivariable survival analyses showed no difference in overall survival (hazard ratio, 1.044; P = .885) in the treatment groups. LN sampling was performed in 50.9% of patients treated with sublobar resection. In this group, LN sampling was not associated with improved survival (84.9% vs 85.0%; P = .741).

CONCLUSIONS

We observed no difference in overall survival between sublobar resection and lobectomy in patients with cTis N0 M0 non-small cell lung cancer with tumors ≤2 cm. Sublobar resection may be an appropriate surgical option for this population. LN sampling was not associated with improved survival in patients treated with sublobar resection.

Esophagectomy vs Gastrectomy for Early Stage Adenocarcinoma of the Gastroesophageal Junction: What is the Optimal Oncologic Surgical Treatment?

Guidelines for the management of gastroesophageal junction (GEJ) adenocarcinoma recommend esophagectomy as the preferred surgical treatment. Gastrectomy has been proposed as an equivalent procedure. This study aims to compare the oncologic outcomes of these operations. The National Cancer Database was queried for patients with clinical T1N0M0 (all sizes) and T2N0M0 (≤2cm) GEJ adenocarcinoma from 2004-2017. Patients treated with surgery-only were included and were stratified by surgical treatment. Propensity-score matching (PSM) was used to create a balanced cohort. Multivariable logistic regression was performed to evaluate for factors predictive of treatment. Kaplan-Meier (KM) and Cox proportional hazards models were used to compare overall survival (OS). 2,446 patients were identified. 75.1% received esophagectomy, while 24.9% were treated with gastrectomy. Patients at high volume facilities were more likely to undergo esophagectomy (OR 1.750, P < 0.001). Factors associated with lower likelihood of undergoing esophagectomy included age ≥75 years (OR 0.588, P = 0.001), female sex (OR 0.706, P = 0.003), and non-White race (OR 0.430, P < 0.001), compared to age ≤50 years, male, and White race, respectively. In the unmatched cohort, gastrectomy was associated with a higher rate of positive margins (4.1% vs 2.3%, P = 0.022). PSM yielded 591 pairs. In the matched cohort, patients treated with esophagectomy had improved 5-year OS compared to gastrectomy (70.6% vs 66.5%, P = 0.030). Multivariable analysis showed improved OS in patients treated with esophagectomy compared to gastrectomy (HR 0.767, P = 0.010). Esophagectomy is associatedwith improved survival and a lower incidence of positive margins in patients with early-stage GEJ adenocarcinoma when compared to gastrectomy.

Utilization and costs of epidermal growth factor receptor mutation testing and targeted therapy in Medicare patients with metastatic lung adenocarcinoma

Background

Guidelines in 2013 and 2014 recommended Epidermal Growth Factor Receptor (EGFR) testing for metastatic lung adenocarcinoma patients as the efficacy of targeted therapies depends on the mutations. However, adherence to these guidelines and the corresponding costs have not been well-studied.

Methods

We identified 2362 patients at least 65 years old newly diagnosed with metastatic lung adenocarcinoma from January 2013 to December 2015 using the SEER-Medicare database. We examined the utilization patterns of EGFR testing and targeted therapies including erlotinib and afatinib. We further examined the costs of both EGFR testing and targeted therapy in terms of Medicare costs and patient out-of-pocket (OOP) costs.

Results

The EGFR testing rate increased from 38% in 2013 to 51% and 49% in 2014 and 2015 respectively. The testing rate was 54% among the 394 patients who received erlotinib, and 52% among the 42 patients who received afatinib. The median Medicare and OOP costs for testing were $1483 and $293. In contrast, the costs for targeted therapy were substantially higher with median 30-day costs at $6114 and $240 for erlotinib and $6239 and $471 for afatinib.

Conclusion

This population-based study suggests that testing guidelines improved the use of EGFR testing, although there was still a large proportion of patients receiving targeted therapy without testing. The costs of targeted therapy were substantially higher than the testing costs, highlighting the need to improve adherence to testing guidelines in order to improve clinical outcomes while reducing the economic burden for both Medicare and patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-07857-y.

Are Routine Chest Radiographs After Chest Tube Removal in Thoracic Surgery Patients Necessary?

INTRODUCTION

The routine use of chest x-ray (CXR) to evaluate the pleural space after chest tube removal is a common practice driven primarily by surgeon preference and institutional protocol. The results of these postpull CXRs frequently lead to additional interventions that serve only to increase health care costs and resource utilization. We investigated the utility of these postpull CXRs in thoracic surgery patients and assessed their effectiveness in predicting the need for tube replacement.

METHODS

Single-institution retrospective study comprising thoracic surgery patients requiring postoperative chest tube drainage over a 3-y period. Demographics and surgical characteristics, including surgical approach, procedure, and procedure type, were recorded. Outcomes included postpull CXR findings, interventions resulting from radiographic abnormalities, and the additional health resource utilization incurred by obtaining these studies on asymptomatic patients.

RESULTS

The study included 433 patients. Postpull CXRs were performed in 87.1% of patients, with 33.2% demonstrating an abnormality compared with the prior study. Among these, 65.7% resulted only in repeat imaging and 25.7% resulted in discharge delay. Overall, a total of 13 patients (3%) required chest tube replacement, three during the index hospitalization and the other 10 requiring readmission. Among those requiring chest tube replacement, 75% had normal postpull imaging, and all were symptomatic.

CONCLUSIONS

Recurrent pneumothorax after chest tube removal requiring immediate tube reinsertion is relatively rare and does not occur in the absence of symptoms. Our study suggests that routine postpull CXRs have limited clinical utility and can be safely omitted in asymptomatic patients with appropriate clinical observation.

Mediastinal IgG4-Related Disease Manifesting as Superior Vena Cava Syndrome

Immunoglobulin G4 (IgG4)-related disease was first identified as a systemic condition in 2003 when extrapancreatic manifestations were identified in patients with autoimmune pancreatitis. Its peak incidence occurs in the fifth or sixth decades of life. Isolated extraaortic mediastinal involvement is extremely rare. This report describes a case of isolated extraaortic mediastinal IgG4-related disease encasing the superior vena cava (SVC) and manifesting as SVC syndrome in a 25-year-old man with no personal or family history of autoimmune disease. Resection with SVC reconstruction was performed.

The Impact of Minimally Invasive Gastrectomy on Survival in the USA

BACKGROUND

Minimally invasive surgical approaches for gastric adenocarcinoma are increasing in prevalence. Although recent studies suggest such approaches are associated with improvements in short-term outcomes, long-term outcomes have not been well studied. This study aimed to evaluate the impact of minimally invasive gastrectomy on long-term survival.

METHODS

The National Cancer Database (NCDB) was used to identify patients who underwent gastrectomy for adenocarcinoma between 2010 and 2015. Patient characteristics were stratified by open and minimally invasive approaches and compared using chi-square and t tests. Unadjusted survival functions were estimated using Kaplan-Meier methodology. Multivariable modeling of risks factors for survival was analyzed with Cox proportional hazard models. Covariate imbalance was controlled using propensity score matching.

RESULTS

The study included 17,449 patients who underwent gastrectomy. Cox proportional hazard modeling demonstrated that minimally invasive surgery improved survival (hazard ratio = 0.86, P < 0.0001). Predictors of worsened survival included community facility type, comorbidities, tumor size, extent of gastrectomy, clinical T and N staging (P < 0.0060 for all). After propensity score matching, minimally invasive surgery had a significantly improved survival at 5 years compared to an open approach, 51.9% versus 47.7% (P < 0.0001). Survival was not significantly different between propensity score-matched patients who received laparoscopic and robotic approaches (P = 0.2611).

CONCLUSIONS

Minimally invasive approaches for gastric carcinoma are associated with improved long-term survival. There was no significant difference in survival when comparing laparoscopic to robotic gastrectomy. The mechanisms that drive these improvements deserve further investigation.

Improving Lung Function in Severe Heterogenous Emphysema with the Spiration Valve System (EMPROVE). A Multicenter, Open-Label Randomized Controlled Clinical Trial

Rationale: Less invasive, nonsurgical approaches are needed to treat severe emphysema.

Objectives: To evaluate the effectiveness and safety of the Spiration Valve System (SVS) versus optimal medical management.

Methods: In this multicenter, open-label, randomized, controlled trial, subjects aged 40 years or older with severe, heterogeneous emphysema were randomized 2:1 to SVS with medical management (treatment) or medical management alone (control).

Measurements and Main Results: The primary efficacy outcome was the difference in mean FEV₁ from baseline to 6 months. Secondary effectiveness outcomes included: difference in FEV₁ responder rates, target lobe volume reduction, hyperinflation, health status, dyspnea, and exercise capacity. The primary safety outcome was the incidence of composite thoracic serious adverse events. All analyses were conducted by determining the 95% Bayesian credible intervals (BCIs) for the difference between treatment and control arms. Between October 2013 and May 2017, 172 participants (53.5% male; mean age, 67.4 yr) were randomized to treatment (n = 113) or control (n = 59). Mean FEV₁ showed statistically significant improvements between the treatment and control groups—between-group difference at 6 and 12 months, respectively, of 0.101 L (95% BCI, 0.060–0.141) and 0.099 L (95% BCI, 0.048–0.151). At 6 months, the treatment group had statistically significant improvements in all secondary endpoints except 6-minute-walk distance. Composite thoracic serious adverse event incidence through 6 months was greater in the treatment group (31.0% vs. 11.9%), primarily due to a 12.4% incidence of serious pneumothorax.

Conclusions: In patients with severe heterogeneous emphysema, the SVS shows significant improvement in multiple efficacy outcomes, with an acceptable safety profile.

Clinical trial registered with www.clinicaltrials.gov (NCT01812447).

Postoperative chemotherapy and radiation improve survival following cardiac sarcoma resection

OBJECTIVE

Cardiac sarcoma represents a rare and aggressive form of cancer with a paucity of data to produce outcome-driven evidence-based guidelines. Current surgical management consists of resection with postoperative therapy (chemotherapy, radiation, or both) offered on a selective, individualized basis. This study was designed to determine whether postoperative therapy was associated with improved overall survival after resection.

METHODS

The National Cancer Database was used to identify patients with cardiac sarcoma between 2004 and 2015. Patient characteristics were stratified by treatment (surgical, nonsurgical, and none), and treatment was analyzed by stage. Overall survival, assessed with Kaplan-Meier methodology, was compared between patients who received postoperative therapy and those who did not following resection. Multivariable survival modeling using a Weibull model identified risk factors associated with survival while controlling for confounders.

RESULTS

The study included 617 patients diagnosed with cardiac sarcoma. Only 24% (149/617) of patients were diagnosed with early-stage disease. Angiosarcoma represented 48% (298/617) of cases and was the most commonly identified histologic subtype. 60% (372/617) underwent surgical resection and 58% (216/372) of those patients were treated with postoperative therapy. Following surgery, median survival was more than doubled for patients treated with postoperative therapy (19 months vs 8 months, P = .026). However, 5-year overall survival was similar between the groups. Multivariable analysis confirmed an improvement in survival with postoperative therapy (hazard ratio, 0.68; 95% confidence interval, 0.51-0.91, P = .009).

CONCLUSIONS

Postoperative therapy is associated with better median survival following resection of cardiac sarcoma. However, at 5 years, the difference in overall survival is not statistically significant.

Readmissions After Lobectomy in an Era of Increasing Minimally Invasive Surgery: A Statewide Analysis

Objective

Utilization of minimally invasive surgical modalities for lobectomy is increasing. Lobectomy can be associated with notable rates of readmission. As use of these modalities increases, evaluation of the impact on readmission is warranted.

Methods

Data from the Pennsylvania Health Care Cost Containment Council were used to identify lobectomy operations performed in Pennsylvania from 2011 through 2014. Operations were stratified by approach: open, video-assisted thoracoscopic surgery (VATS) or robotic. Differences in patient characteristics were assessed with analysis of variance and chi-squared tests. Logistic regression modeled risk of 30-day readmission and linear regression modeled length of stay (LOS) after controlling for confounders.

Results

We evaluated 4,939 lobectomy operations (2,501 open, 1,944 VATS, 494 robotic) with 583 readmissions (11.8%). Robotic cases increased 333% over 4 years. VATS and open cases increased 38% and 22%, respectively. Surgical approach was not associated with hospital readmission (VATS odds ratio (OR) = 0.95; P = 0.632; and robotic OR = 1.02; P = 0.916). Longer LOS was associated with a greater likelihood of readmission (OR = 1.58; P = 0.002). LOS was 1 day less for VATS ( P < 0.001) and 1.5 days less for robotic lobectomy ( P < 0.001) when compared to an open approach. The most common reasons for readmission were respiratory complications and nonrespiratory infection.

Conclusions

Surgical approach does not directly affect readmission. However, minimally invasive lobectomy appears to be associated with shorter LOS and results in more patients discharged home. Decreased LOS and discharge home are associated with fewer readmissions.

Chest Tube Drainage Devices

Placement of a chest tube drains intrapleural fluid and air. The tube should be attached to a drainage system, such as one-, two-, or three-compartment devices, a one-way (Heimlich) valve for ambulatory drainage, a digital system, or a vacuum bottle. The frequently employed three-compartment systems, currently integrated disposable units, allow adjustment of negative pressure or no suction (water seal), and include an air leak meter on the water seal chamber to be used for demonstrating and quantifying air leak. These readings are subjective and prone to interobserver variability. Digital pleural drainage systems offer the benefits of quantification of any air leak and pleural pressure. Indwelling pleural catheters, typically utilized for malignant pleural effusion, can be drained using vacuum bottles. Knowledge of the design and functionality of each device in the setting of an individual patient's specific pleural process facilitates the selection of practical and financially prudent chest tube drainage strategies.

Minimally Invasive Lobectomy Modality and Other Predictors of Conversion to Thoracotomy

OBJECTIVE

Minimally invasive approaches to lobectomy are increasing. Rates of conversion to thoracotomy are well reported but risk factors are poorly understood. This study aimed to determine the impact of surgical modality (video-assisted thoracoscopic surgery [VATS] and robotic) on conversion as well as to identify other risk factors for conversion.

METHODS

The National Cancer Database (NCDB) was used to identify patients who underwent minimally invasive lobectomy between 2010 and 2015. Patient characteristics were compared between VATS and robotic approaches using chi-squared tests and t-tests. Logistic regression models were used to control for covariates and identify factors associated with all minimally invasive conversion, VATS conversion, and robotic conversion. Propensity score matching was used to compare conversion rates of VATS and robotic lobectomy.

RESULTS

The study included 51,723 patients with lung cancer who underwent minimally invasive lobectomy (VATS or robotic). Conversion was identified in 7,109 (7.3%) operations. The odds of VATS conversions were nearly twice that of robotic conversions (OR 1.94 P < 0.0001). After controlling for VATS and robotic patient imbalances with propensity score matching, there was a 5% difference in conversion rates (14% vs. 9%, P < 0.0001). Other predictors of minimally invasive conversion included community hospitals, tumor size 4.5 cm or greater, and an increasing Charlson comorbidity index (P < 0.03 for all).

CONCLUSIONS

VATS is associated with nearly twice the odds of conversion as robotic lobectomy. Identifying specific risk factors for both VATS and robotic conversions may aid in appropriate modality selection and reduction of conversions.

Perioperative chemotherapy is not associated with improved survival in stage I pleomorphic lung cancer

OBJECTIVES

Pulmonary pleomorphic carcinoma represents an understudied, rare, and aggressive histologic subtype of non-small cell lung cancer. Better understanding of rare disease subtypes allows for improved individualization of patient care. This study aimed to evaluate current trends in treatment and survival of pleomorphic carcinoma.

METHODS

The National Cancer Database was used to identify patients with staged, pleomorphic carcinoma and adenocarcinoma between 2004 and 2015. Patient characteristics and treatments were compared using χ² tests. Cox proportional hazard models examined survival by stage after controlling for confounders. Propensity score matched Kaplan-Meier curves estimated survivor functions stratified by stage. Differences in survival following treatment for stage I pleomorphic carcinoma with surgery alone versus surgery plus chemotherapy were compared with Cox proportional hazard models and Kaplan-Meier survival curves.

RESULTS

One thousand four hundred eight patients with pleomorphic carcinoma and 607,561 patients with adenocarcinoma were identified. Pleomorphic carcinoma accounted for 0.1% of all non-small cell lung cancers. Pleomorphic disease had poorer overall 5-year survival compared with adenocarcinoma for stages I through IV (49.4% vs 59.1%, 34.5% vs 43.8%, 16.9% vs 28.4%, and 5.7% vs 7.8%, respectively; P < .0047 for all). Perioperative chemotherapy was used more frequently for pleomorphic disease (17.5% vs 6.1%; P < .001). For stage I pleomorphic cancer, treatment with surgery alone (n = 253) and surgery with chemotherapy (n = 57) had overall 5-year survival rates of 55.2% and 53.7%, respectively, and were not significantly different (P = .2868).

CONCLUSIONS

Pulmonary pleomorphic carcinoma is rare and aggressive, with worse survival when compared with adenocarcinoma. Perioperative chemotherapy has not demonstrated significant survival benefits in stage I pleomorphic cancer.

Robotic-Assisted Versus Thoracoscopic Lobectomy Outcomes From High-Volume Thoracic Surgeons

BACKGROUND

Reports of surgical outcomes comparing proficient surgeons who perform either robotic-assisted or video-assisted thoracoscopic lobectomy are lacking. We evaluate the comparative effectiveness of robotic-assisted and video-assisted thoracoscopic lobectomies by surgeons who performed 20 or more annual surgical procedures in a national database.

METHODS

Patients 18 years or older, who underwent elective lobectomy by surgeons who performed 20 or more annual lobectomies by robotic-assisted or thoracoscopic approach from January 2011 through September 2015, were identified in the Premier Healthcare database with the use of codes from the ninth revision of the International Statistical Classification of Diseases and Related Health Problems. Propensity-score matching based on patient and hospital characteristics and by year was performed 1:1 to identify comparable cohorts for analysis (n = 838 in each cohort). All tests were two-sided, with statistical significance set at p less than 0.05.

RESULTS

A total of 23,779 patients received an elective lobectomy during the study period: 9,360 were performed by video-assisted thoracoscopic approach and 2,994 were by robotic-assisted approach. Propensity-matched comparison of lobectomies performed by surgeons who performed 20 or more procedures annually (n = 838) showed that robotic-assisted procedures had a longer mean operative time by 25 minutes (mean 247.1 minutes vs 222.6 minutes, p < 0.0001) but had a lower conversion-to-open rate (4.8% vs 8.0%, p = 0.007) and a lower 30-day complication rate (33.4% vs 39.2%, p = 0.0128). Transfusion rates and 30-day mortality rates were similar between the two cohorts.

CONCLUSIONS

When surgical outcomes are limited to surgeons who perform 20 or more annual procedures, the robotic-assisted approach is associated with a lower conversion-to-open rate and lower 30-day complication rate when than video-assisted thoracoscopic surgeons, with a mean operative time difference of 25 minutes.

Circulating tumor cell isolation during resection of colorectal cancer lung and liver metastases: a prospective trial with different detection techniques

BACKGROUND

Colorectal cancer (CRC) metastasectomy improves survival, however most patient develop recurrences. Circulating tumor cells (CTCs) are an independent prognostic marker in stage IV CRC. We hypothesized that CTCs can be enriched during metastasectomy applying different isolation techniques.

METHODS

25 CRC patients undergoing liver (16 (64%)) or lung (9 (36%)) metastasectomy were prospectively enrolled (clinicaltrial.gov identifier: NCT01722903). Central venous (liver) or radial artery (lung) tumor outflow blood (7.5 ml) was collected at incision, during resection, 30 min after resection, and on postoperative day (POD) 1. CTCs were quantified with 1. EpCAM-based CellSearch® system and 2. size-based isolation with a novel filter device (FMSA). CTCs were immunohistochemically identified using CellSearch®'s criteria (cytokeratin 8/18/19+, CD45- cells containing a nucleus (DAPI+)). CTCs were also enriched with a centrifugation technique (OncoQuick®).

RESULTS

CTC numbers peaked during the resection with the FMSA in contrast to CellSearch® (mean CTC number during resection: FMSA: 22.56 (SEM 7.48) (p = 0.0281), CellSearch®: 0.87 (SEM ± 0.44) (p = 0.3018)). Comparing the 2 techniques, CTC quantity was significantly higher with the FMSA device (range 0-101) than CellSearch® (range 0-9) at each of the 4 time points examined (P < 0.05). Immunofluorescence staining of cultured CTCs revealed that CTCs have a combined epithelial (CK8/18/19) and macrophage (CD45/CD14) phenotype.

CONCLUSIONS

Blood sampling during CRC metastasis resection is an opportunity to increase CTC capture efficiency. CTC isolation with the FMSA yields more CTCs than the CellSearch® system. Future studies should focus on characterization of single CTCs to identify targets for molecular therapy and immune escape mechanisms of cancer cells.

Endobronchial Valves for Challenging Air Leaks

BACKGROUND

Prolonged air leaks may result in increased morbidity and mortality. Endobronchial valves have been used as a nonoperative treatment. We evaluated the efficacy of endobronchial valves at achieving chest tube removal and hospital discharge for air leaks resulting from varied etiologies.

METHODS

All consecutive patients undergoing endobronchial valve placement for persistent air leak were evaluated by a multidisciplinary team at a single institution. Those receiving valves underwent bronchoscopy with balloon occlusion to identify airways contributing to the leak. After airway sizing, unidirectional endobronchial valves were deployed.

RESULTS

During an 18-month period, 21 patients underwent 24 valve placement procedures; 88 valves were placed (median, 3; mean, 3.6; range, 1 to 12). Patient age range was 16 months to 70 years. The underlying cause of persistent air leak was postoperative (n = 8), pneumothorax (n = 11), cavitary lung infection (n = 3), and postpneumonectomy bronchopleural fistula (n = 2). There were no valve-related complications during placement, dwell time, or removal. Three patients died as a result of their underlying disease, unrelated to valves. Of those with chest tubes who survived and were discharged, all had successful removal of their chest tubes. Median duration to chest tube removal after initial valve placement was 15 days (mean, 21 days; range, 0 to 86 days). Median length of stay after final valve placement was 5 days (mean, 15 days; range, 0 to 196 days).

CONCLUSIONS

Challenging air leaks often occur in medically compromised patients. They may persist despite multiple interventions. Endobronchial valves offer minimally invasive management. Time to chest tube removal and length of stay are variable, frequently because of clinical status and underlying disease.

Nodal stage of surgically resected non-small cell lung cancer and its effect on recurrence patterns and overall survival

PURPOSE

Current National Comprehensive Cancer Network guidelines recommend postoperative radiation therapy (PORT) for patients with resected non-small cell lung cancer (NSCLC) with N2 involvement. We investigated the relationship between nodal stage and local-regional recurrence (LR), distant recurrence (DR) and overall survival (OS) for patients having an R0 resection.

METHODS AND MATERIALS

A multi-institutional database of consecutive patients undergoing R0 resection for stage I-IIIA NSCLC from 1995 to 2008 was used. Patients receiving any radiation therapy before relapse were excluded. A total of 1241, 202, and 125 patients were identified with N0, N1, and N2 involvement, respectively; 161 patients received chemotherapy. Cumulative incidence rates were calculated for LR and DR as first sites of failure, and Kaplan-Meier estimates were made for OS. Competing risk analysis and proportional hazards models were used to examine LR, DR, and OS. Independent variables included age, sex, surgical procedure, extent of lymph node sampling, histology, lymphatic or vascular invasion, tumor size, tumor grade, chemotherapy, nodal stage, and visceral pleural invasion.

RESULTS

The median follow-up time was 28.7 months. Patients with N1 or N2 nodal stage had rates of LR similar to those of patients with N0 disease, but were at significantly increased risk for both DR (N1, hazard ratio [HR] = 1.84, 95% confidence interval [CI]: 1.30-2.59; P=.001; N2, HR = 2.32, 95% CI: 1.55-3.48; P<.001) and death (N1, HR = 1.46, 95% CI: 1.18-1.81; P<.001; N2, HR = 2.33, 95% CI: 1.78-3.04; P<.001). LR was associated with squamous histology, visceral pleural involvement, tumor size, age, wedge resection, and segmentectomy. The most frequent site of LR was the mediastinum.

CONCLUSIONS

Our investigation demonstrated that nodal stage is directly associated with DR and OS but not with LR. Thus, even some patients with, N0-N1 disease are at relatively high risk of local recurrence. Prospective identification of risk factors for local recurrence may aid in selecting an appropriate population for further study of postoperative radiation therapy.

Pleural space infections after image-guided percutaneous drainage of infected intraabdominal fluid collections: a retrospective single institution analysis

Background

Percutaneous drainage of infected intraabdominal fluid collections is preferred over surgical drainage due to lower morbidity and costs. However, it can be a challenging procedure and catheter insertion carries the potential to contaminate the pleural space from the abdomen. This retrospective analysis demonstrates the clinical and radiographic correlation between percutaneous drainage of infected intraabdominal collections and the development of iatrogenic pleural space infections.

Methods

A retrospective single institution analysis of 550 consecutive percutaneous drainage procedures for intraabdominal fluid collections was performed over 24 months. Patient charts and imaging were reviewed with regard to pleural space infections that were attributed to percutaneous drain placements. Institutional review board approval was obtained for conduct of the study.

Results

6/550 (1.1%) patients developed iatrogenic pleural space infections after percutaneous drainage of intraabdominal fluid collections. All 6 patients presented with respiratory symptoms and required pleural space drainage (either by needle aspiration or chest tube placement), 2 received intrapleural fibrinolytic therapy and 1 patient had to undergo surgical drainage. Pleural effusion cultures revealed same bacteria in both intraabdominal and pleural fluid in 3 (50%) cases. A video with a dynamic radiographic sequence demonstrating the contamination of the pleural space from percutaneous drainage of an infected intraabdominal collection is included.

Conclusions

Iatrogenic pleural space infections after percutaneous drainage of intraabdominal fluid collections occur at a low incidence, but the pleural empyema can be progressive requiring prompt chest tube drainage, intrapleural fibrinolytic therapy or even surgery. Expertise in intraabdominal drain placements, awareness and early recognition of this complication is critical to minimize incidence, morbidity and mortality in these patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12893-015-0030-4) contains supplementary material, which is available to authorized users.

Endobronchial occlusion with one-way endobronchial valves: a novel technique for persistent air leaks in children

PURPOSE

In children, persistent air leaks can result from pulmonary infection or barotrauma. Management strategies include surgery, prolonged pleural drainage, ventilator manipulation, and extracorporeal membrane oxygenation (ECMO). We report the use of endobronchial valve placement as an effective minimally invasive intervention for persistent air leaks in children.

METHODS

Children with refractory prolonged air leaks were evaluated by a multidisciplinary team (pediatric surgery, interventional pulmonology, pediatric intensive care, and thoracic surgery) for endobronchial valve placement. Flexible bronchoscopy was performed, and air leak location was isolated with balloon occlusion. Retrievable one-way endobronchial valves were placed.

RESULTS

Four children (16 months to 16 years) had prolonged air leaks following necrotizing pneumonia (2), lobectomy (1), and pneumatocele (1). Patients had 1-4 valves placed. Average time to air leak resolution was 12 days (range 0-39). Average duration to chest tube removal was 25 days (range 7-39). All four children had complete resolution of air leaks. All were discharged from the hospital. None required additional surgical interventions.

CONCLUSION

Endobronchial valve placement for prolonged air leaks owing to a variety of etiologies was effective in these children for treating air leaks, and their use may result in resolution of fistulae and avoidance of the morbidity of pulmonary surgery.

Endobronchial valve placement as destination therapy for recurrent pneumothorax in the setting of advanced malignancy

The development of a persistent air leak after pneumothorax can be encountered in patients with underlying structural lung disease. In those with advanced malignancy or other comorbidities, the ability to tolerate general anesthesia and thoracoscopic procedures may limit definitive management. We describe the case of a 68-y-old male with refractory acute myelogenous leukemia presenting with recurrent secondary spontaneous pneumothorax and persistent air leak related to an underlying fungal pneumonia. Endobronchial valve placement allowed for timely chest tube removal and discharge from the hospital, as well as avoidance of a thoracoscopic procedure and pleurodesis.

Would screening for lung cancer benefit 75- to 84-year-old residents of the United States?

Background: The National Lung Screening Trial demonstrated that screening for lung cancer improved overall survival (OS) and reduced lung cancer mortality in the 55- to 74-year-old age group by increasing the proportion of cancers detected at an early stage. Because of the increasing life expectancy of the American population, we investigated whether screening for lung cancer might benefit men and women aged 75–84 years.

Materials/Methods: Rates of non-small cell lung cancer (NSCLC) from 2000 to 2009 were calculated in both younger and older age groups using the surveillance epidemiology and end reporting database. OS and lung cancer-specific survival (LCSS) in patients with Stage I NSCLC diagnosed from 2004 to 2009 were analyzed to determine the effects of age and treatment.

Results: The per capita incidence of NSCLC decreased in the 55–74 cohort, but increased in the 75–84 cohort over the study period. Crude lung cancer death rates in the two age groups who had no specific treatment were 39.5 and 44.9%, respectively. These rates fell in both age groups when increasingly aggressive treatment was used. Rates of OS and LCSS improved significantly with increasingly aggressive treatment in the 75–84 age group. The survival benefits of increasingly aggressive treatment in 75- to 84-year-old females did not differ from their counterparts in the younger cohort.

Conclusion: Screening for lung cancer might be of benefit to individuals at increased risk of lung cancer in the 75–84 age group. The survival benefits of aggressive therapy are similar in females between 55–74 and 75–84 years old.

Endobronchial valve placement for spontaneous pneumothorax from stage IIIA non-small cell lung cancer facilitates neoadjuvant therapy

Spontaneous pneumothorax has previously been described as a presenting symptom of lung cancer. This presentation can, unfortunately, complicate and delay further definitive oncologic care until the pneumothorax can be effectively managed. We describe the case of a 58-year-old man who presented with secondary spontaneous pneumothorax and persistent air leak related to his primary lung carcinoma. Endobronchial valve placement allowed for the avoidance of pleurodesis, timely discharge, and neoadjuvant chemotherapy, followed by definitive surgical resection.

Specimen processing techniques for endobronchial ultrasound-guided transbronchial needle aspiration

BACKGROUND

Endobronchial ultrasound is used for sampling thoracic pathologic processes. Histologic examination may provide added diagnostic yield to cytologic preparations owing to superior assessment of architecture and immunohistochemistry. It remains unclear whether specific specimen processing technique impacts diagnostic yield. We hypothesized that diagnostic yield using histologic analysis of core needle biopsies is higher than cytologic preparations alone.

METHODS

We evaluated 177 consecutive patients with mediastinal abnormalities. An interventional pulmonologist or thoracic surgeon performed endobronchial ultrasound. We compared diagnostic yields of two specimen processing techniques, fixed slides (cytology) and formalin-fixed core samples (histology). Results were categorized as malignant, benign (infectious, inflammatory), normal nodal tissue, or inadequate sampling (nondiagnostic). Malignancy, a defined benign process, and normal lymph node were considered diagnostic.

RESULTS

The diagnostic yield for benign processes was higher by histologic examination (n = 37) than in cytologic preparations (n = 22; p = 0.0064). The diagnostic yield was comparable in malignancy (p = 0.7530). The combination of both techniques provided a higher overall diagnostic rate: 84% (n = 148) by histology, 82% (n = 146) by cytology, and 89% (n = 158) using both. Using two techniques revealed discordance in 23% (n = 40), demonstrating that the use of one technique alone would have resulted in missed diagnoses.

CONCLUSIONS

Adding histologic analysis of tissue cores obtained by endobronchial ultrasound offers higher diagnostic accuracy than only cytologic preparation of needle aspirates. Histologic and cytologic methods offer comparable diagnostic rates for malignancy. However, diagnostic yield for benign conditions is higher using histologic examination. Together, histology and cytology provide fewer missed diagnoses than either individually. When using endobronchial ultrasound, it is ideal to routinely use both needle aspirate cytology and core biopsy histology.

Video-assisted thoracoscopic splanchnicectomy for pain control in chronic pancreatitis

BACKGROUND

: Management of pain in patients with chronic pancreatitis can be frustrating. The authors retrospectively evaluated their experience with video-assisted thoracoscopic surgery (VATS) for pain secondary to chronic pancreatitis.

METHODS

: From September 1999 to August 2004, 16 patients underwent VATS for pain associated with chronic pancreatitis. Data were collected retrospectively.

RESULTS

: Eight patients were female and 8 were male. Their ages ranged from 17 to 81 years, with a mean age of 40 years. There were 22 VATS splanchnicectomies performed: 7 right, 10 left, and 5 bilateral. The average operative time was 75 minutes for right VATS splanchnicectomy, 86 minutes for left VATS splanchnicectomy, and 88 minutes for bilateral VATS splanchnicectomies. The average length of stay (LOS) was 2.6 days after right VATS splanchnicectomy, 2.2 days after left VATS splanchnicectomy, and 1 day after bilateral VATS splanchnicectomies. Two cases were nonelective and not included in the determination of LOS. No postoperative complications occurred in any of the patients admitted for elective operations. Postoperative mortality was zero. Complete resolution of pain occurred in 4 patients (25%): 1 right splanchnicectomy, 1 left splanchnicectomy, and 2 bilateral splanchnicectomies. Total pancreatectomy with islet cell transplant was subsequently performed in 5 patients (31%), who improved but then had recurrent pain. Continued chronic pain managed with nonsteroidal antiinflammatory drugs and narcotic analgesics was the result in 7 patients (44%)

CONCLUSIONS

: Video-assisted thoracoscopic splanchnicectomy surgery may alleviate pain in patients with chronic pancreatitis. It can be performed with minimal morbidity and mortality, and has been safe and useful in the workup, evaluation, and management of pain associated with chronic pancreatitis.

Can lung cancer screening by computed tomography be effective in areas with endemic histoplasmosis?

OBJECTIVE

Low-dose chest computed tomography (CT) is being evaluated in several national trials as a screening modality for the early detection of lung cancer. The goal of the present study was to determine whether lung cancer screening could be done while minimizing the number of benign biopsy specimens taken in an area endemic for histoplasmosis.

METHODS

The subjects were recruited by letters mailed to area physicians and local advertisement. The inclusion criteria were age older than 50 years and at least a 20 pack-year smoking history. The exclusion criteria were symptoms suggestive of lung cancer or a history of malignancy in the previous 5 years. The participants completed a questionnaire and underwent a chest CT scan at baseline and annually for 5 years. The management of positive screening results was determined using a defined algorithm: annual follow-up CT scan for nodules less than 5 mm; 6-month follow-up CT scan for nodules 5 to 7 mm; review by our multidisciplinary tumor board for nodules 8 to 12 mm; and biopsy for nodules greater than 12 mm.

RESULTS

A total of 132 patients were recruited. Of the 132 patients, 61% had positive baseline CT findings and 22% had positive findings on the annual CT scans. Six cancers were detected. Of these 6 patients, 5 had stage I disease and underwent lobectomy, and 1 had stage IIIA disease and underwent induction chemotherapy and radiotherapy followed by lobectomy. All patients were alive and disease free at a mean follow-up of 41.7 ± 18.6 months. No biopsies were performed for benign lesions. Also, no cancers were missed when the protocol was followed.

CONCLUSIONS

Screening with CT can be done effectively in an area endemic for histoplasmosis while minimizing benign biopsies.

Indications and approach to surgical resection of lung metastases

Pulmonary metastasectomy is a curative option for selected patients with cancer spread to the lungs. Complete surgical removal of pulmonary metastases can improve survival and is recommended under certain criteria. Specific issues that require consideration in a multidisciplinary setting when planning pulmonary metastasectomy include: adherence to established indications for resection, the surgical strategy including the use of minimally invasive techniques, pulmonary parenchyma preservation, and the role of lymphadenectomy.

Traumatic diaphragmatic injury: experience from a level I trauma center

OBJECTIVE

Traumatic diaphragmatic injuries (TDI) are uncommon but associated with substantial morbidity and mortality. We sought to analyze patients with TDI at a large trauma center and associated county coroner to identify characteristics predictive of increased mortality.

METHODS

We queried a level I university trauma center and associated county coroner databases containing >20,000 patients to identify patients with ICD-9 diagnoses pertaining to TDI from January 1992 through May 2005. Once identified, hospital records, operative details, and autopsy reports were reviewed to determine injury characteristics, treatment provided, and outcome. Statistical analyses were performed using the Student t-test, chi-square analysis, analysis of variance, and multiple logistic regression.

RESULTS

TDI were identified in 254 individuals. Two hundred (79%) survived to undergo operation. Of the 81 (32%) deaths, 33 (41%) occurred before arrival at the trauma center. Survivors were younger, had lesser injury severity scores (ISS), were more likely to be female, and had more bilateral injuries (P < or = .002 all) than nonsurvivors. By multiple logistic regression analyses, increased age (odds ratio [OR], 1.044; 95% confidence interval [CI], 1.015-1.074; P = .0029) and greater ISS (OR, 1.145; 95% CI, 1.103-1.188; P < .0001) were predictors of the probability of death in all patients.

CONCLUSION

Although TDI may indicate substantive trauma burden in any patient, those with greater ISS and advanced age are at the greatest risk of death.

Efficacy of intrapleural tissue-type plasminogen activator in the treatment of loculated parapneumonic effusions

PURPOSE

To assess the feasibility and effectiveness of intrapleural recombinant tissue-type plasminogen activator (r-tPA) in the treatment of loculated parapneumonic effusions (PPEs).

MATERIALS AND METHODS

A single-arm prospective study of 25 consecutive patients with loculated PPEs was analyzed. All patients received 6-mg doses of intrapleural r-tPA on a defined schedule via a thoracostomy tube. The volume of output from the tubes was recorded and analysis of the fluid composition performed. Follow-up was both clinical and radiographic, with all patients undergoing pre- and postprocedural computed tomography.

RESULTS

Eighteen of the 25 patients (72%) required no additional intervention and had a complete clinical and radiographic response with the fibrinolytic therapy. Seven patients (28%) were treated with video-assisted thoracoscopic surgery, but no patient required thoracotomy for total decortication. There were no hemorrhagic complications.

CONCLUSIONS

Intrapleural r-tPA is effective in the treatment of loculated PPEs. It can be performed safely and in some patients may avoid the need for additional surgical intervention.

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.

Robotic Heller myotomy: a safe operation with higher postoperative quality-of-life indices

INTRODUCTION

Achalasia is a primary motility disorder of the esophagus that is treated most effectively with operative myotomy. Excellent outcomes with laparoscopic myotomy and fundoplication are well known. Heller myotomy utilizing a computer-enhanced (robotic) laparoscopic platform allows for a more precise dissection by utilizing the superior optics of a 3-dimensional camera and greater degrees of freedom provided by robotic instrumentation. How this affects outcome and quality of life is unknown.

METHODS

We assessed patients' health perceptions using a standardized, validated, health-related, disease-specific quality-of-life metric. Sixty-one consecutive patients undergoing laparoscopic or robotic myotomy over a 6-year period were evaluated prospectively. All operations were performed using intraoperative manometric and endoscopic guidance and all except 5 patients had a fundoplication. The effects of the operation on health-related quality of life were evaluated with the Short Form (SF-36) Health Status Questionnaire and a disease-specific gastroesophageal reflux disease activity (GERD) activity index (GRACI) preoperatively and postoperatively. All patients completed the questionnaire at both time points. Patient scores were compared using 2-way repeated measures analyses of variance followed by the Tukey test. Operative time, estimated blood loss, duration of stay, intraoperative complication, and postoperative complications were analyzed.

RESULTS

Thirty-seven patients had laparoscopic and 24 patients had robotic Heller myotomy. There was an increase in SF-36 overall evaluation of health postoperatively compared with preoperatively in both groups (P < .05). The robotic myotomy patients had better SF-36 Role Functioning (emotional) and General Health Perceptions (P < .05) compared with the laparoscopic group. The GRACI showed an equivalent improvement in severity of symptoms in both groups (P < .05). Operative time was 287 +/- 9 minutes for laparoscopic cases and 355 +/- 23 minutes for robotic cases. Estimated blood loss and duration of stay were not different between groups. There were 3 operative esophageal perforations (8%) during laparoscopic myotomy and all were repaired immediately. There were no perforations or operative complications in the robotic group. Neither group had any additional complications.

CONCLUSIONS

Minimally invasive operative myotomy improves functional status and overall evaluation of health in patients with achalasia. Robotic myotomy had no intraoperative esophageal perforations compared with an 8% intraoperative rate during laparoscopic myotomy. Heller myotomy with partial fundoplication using a robotic platform appears to be a more precise and safer operation than laparoscopic myotomy with improved quality-of-life indices postoperatively compared with laparoscopic myotomy with fewer complications; this suggests that, in skilled hands, the robotic platform may be safer, with improved quality-of-life outcomes.

Retinoblastoma deficiency increases chemosensitivity in lung cancer

The retinoblastoma (RB) tumor suppressor is mutated or functionally inactivated in the majority of human malignancies, and p16(INK4a)-cyclin D1-cyclin-dependent kinase 4-RB pathway aberrations are present in nearly all cases of non-small cell lung cancer (NSCLC). Here, the distinct role of RB loss in tumorigenic proliferation and sensitivity to chemotherapeutics was determined in NSCLC cells. Attenuation of RB led to a proliferative advantage in vitro and aggressive tumorigenic growth in xenograft models. Clinically, such aggressive disease is treated with genotoxic and cytotoxic chemotherapeutic agents. In vitro analysis showed that RB deficiency resulted in bypass of the checkpoint response to multiple chemotherapeutic challenges concomitant with an elevated apoptotic response. Correspondingly, RB deficiency in xenograft models led to increased chemosensitivity. However, this response was transient, and a durable response was dependent on prolonged chemotherapeutic administration. Together, these findings show that although RB deficiency enhances sensitivity to chemotherapeutic challenge, efficient and sustainable response is highly dependent on the specific therapeutic regimen, in addition to the molecular environment.

RB activity alters checkpoint response and chemosensitivity in lung cancer lines

BACKGROUND

The retinoblastoma tumor suppressor (RB) is a key regulator of cell cycle progression and is functionally inactivated in the majority of human non-small cell lung cancers (NSCLC). The specific influence of RB on therapeutic response in NSCLC remains elusive.

MATERIALS AND METHODS

We investigated the consequence of reintroduction of RB on checkpoint response and chemosensitivity in NSCLC cell lines. RB introduction into RB-proficient (NCI-H1299) and -deficient (H1734, H2172) NSCLC cells was achieved by adenoviral infection. RB/E2F target gene expression was determined by immunoblot analysis. Cell cycle response and viability after chemotherapeutic exposure were assessed by flow cytometry and MTT viability assay.

RESULTS

RB reconstitution in RB-deficient lines restored regulation of topoIIalpha, thymidylate synthase, and cyclin A. Similarly, RB overexpression in RB-proficient cells caused further regulation of some RB/E2F target genes including thymidylate synthase and topoIIalpha. In addition, RB overexpression resulted in restoration of the G1 arrest mechanism. Exposure of RB-proficient cells to cisplatin, etoposide, or 5-fluorouracil elicited arrest in various phases of the cell cycle while lines deficient for RB exhibited different checkpoint responses. However, introduction of RB restored ability to arrest following chemotherapeutic exposure. Chemotherapeutic challenge resulted in varying effects on cellular viability independent of RB status, yet restoration of RB activity conferred partial chemoresistance.

CONCLUSIONS

These results demonstrate that RB reconstitution into RB-deficient NSCLC lines establishes regulation of certain RB/E2F target genes and restores G1 arrest mechanisms. Furthermore, introduction of RB enhances the G1 checkpoint response to chemotherapeutics and decreases chemosensitivity. Knowledge of RB-dependent chemosensitivity may ultimately contribute to individualized therapy based on molecular characterization of tumors.

Loss of the retinoblastoma tumor suppressor: differential action on transcriptional programs related to cell cycle control and immune function

Functional inactivation of the retinoblastoma tumor suppressor gene product (RB) is a common event in human cancers. Classically, RB functions to constrain cellular proliferation, and loss of RB is proposed to facilitate the hyperplastic proliferation associated with tumorigenesis. To understand the repertoire of regulatory processes governed by RB, two models of RB loss were utilized to perform microarray analysis. In murine embryonic fibroblasts harboring germline loss of RB, there was a striking deregulation of gene expression, wherein distinct biological pathways were altered. Specifically, genes involved in cell cycle control and classically associated with E2F-dependent gene regulation were upregulated via RB loss. In contrast, a program of gene expression associated with immune function and response to pathogens was significantly downregulated with the loss of RB. To determine the specific influence of RB loss during a defined period and without the possibility of developmental compensation as occurs in embryonic fibroblasts, a second system was employed wherein Rb was acutely knocked out in adult fibroblasts. This model confirmed the distinct regulation of cell cycle and immune modulatory genes through RB loss. Analyses of cis-elements supported the hypothesis that the majority of those genes upregulated with RB loss are regulated via the E2F family of transcription factors. In contrast, those genes whose expression was reduced with the loss of RB harbored different promoter elements. Consistent with these analyses, we found that disruption of E2F-binding function of RB was associated with the upregulation of gene expression. In contrast, cells harboring an RB mutant protein (RB-750F) that retains E2F-binding activity, but is specifically deficient in the association with LXCXE-containing proteins, failed to upregulate these same target genes. However, downregulation of genes involved in immune function was readily observed with disruption of the LXCXE-binding function of RB. Thus, these studies demonstrate that RB plays a significant role in both the positive and negative regulations of transcriptional programs and indicate that loss of RB has distinct biological effects related to both cell cycle control and immune function.

Preliminary Report of a Prospective, Randomized Trial of Underwater Seal for Spontaneous and Iatrogenic Pneumothorax

BACKGROUND

Management of pneumothorax has traditionally been tube thoracostomy and -20 cm H2O suction. The purpose of our study was to determine if underwater seal in iatrogenic and spontaneous pneumothoraces is safe and efficacious and if small-caliber chest tubes are appropriate for routine use in pneumothorax.

STUDY DESIGN

From April 2001 through October 2003 patients with iatrogenic or spontaneous pneumothorax were enrolled in this prospective, randomized trial. Small-bore catheters were inserted. Initial management was 1 hour -20 cm H2O suction, chest radiography, and randomization into -20 cm H2O suction, -10 cm H2O suction, or underwater seal. Tubes were discontinued at 48 hours if there were no pneumothoraces and no air leaks. Those with air leaks and recurrent pneumothoraces persisting 5 days underwent pleurodesis. The primary end point was successful chest tube removal at 48 hours. The secondary end point was need for pleurodesis.

RESULTS

Twenty-nine patients were analyzed. Seven were randomized to -20 cm H2O suction, 11 to -10 cm H2O suction, and 11 to underwater seal. Most (59%, 17 of 29) chest tubes were successfully removed 48 hours after placement: 57% (4 of 7) after -20 cm H2O suction, 73% (8 of 11) after -10 cm H2O suction, and 45% (5 of 11) after underwater seal (p = 0.48). Seven (24%) required pleurodesis: 29% (2 of 7) after -20 cm H2O suction, 27% (3 of 11) after -10 cm H2O suction, and 18% (2 of 11) after underwater seal (p = 0.70).

CONCLUSIONS

Early underwater seal appears to be safe for treating iatrogenic and spontaneous pneumothoraces. It can achieve comparable frequencies of early chest tube removal and avoidance of operation compared with traditional management. A larger, multi-institutional study should be performed to demonstrate that pneumothorax treatment can effectively incorporate small-caliber tubes and underwater seal.

A phase II study of sequential neoadjuvant gemcitabine and paclitaxel, radiation therapy with cisplatin and 5-fluorouracil and surgery in locally advanced esophageal carcinoma

OBJECTIVE

To evaluate the feasibility and efficacy of sequential neoadjuvant chemotherapy, chemoradiation, and surgery in patients with locally advanced esophageal cancer.

PATIENTS AND METHODS

There were 29 patients who received paclitaxel 150 mg/m2 and gemcitabine 3000 mg/m2 2 weeks apart. Two weeks later, patients received cisplatin 75 mg/m2 and 5-fluorouracil (5-FU) 1000 mg/m2/d continuous infusion for 4 days with concurrent radiotherapy in 15 fractions to a total dose of 4000 cGy. After 6 weeks, cisplatin and 5-FU were repeated at the above doses. After 4 to 6 weeks, patients were restaged and underwent surgical resection.

RESULTS

All 29 patients completed the prescribed gemcitabine, paclitaxel, and radiation therapy. Febrile neutropenia occurred in 1 patient and 4 patients received growth factor support. After neoadjuvant treatment, 1 patient refused surgery, 23 underwent R0 resection (82%), while 5 developed progressive disease. Four patients developed anastomotic leaks (17%). Four patients had complete pathologic responses (14%) and 4 (14%) had only residual microscopic disease. Nine patients remain alive at a median follow-up of 48 months. Three-year survival for the entire cohort was 36%.

CONCLUSION

This regimen was associated with a high rate of compliance and induction therapy had an acceptable toxicity profile. The R0 resection rate and 3-year survival data are similar to recently reported studies. While active, gemcitabine and paclitaxel induction therapy was associated with an increased rate of postoperative complications, but no increase in survival. Patterns of failure continue to demonstrate the need for regimens incorporating greater emphasis on systemic therapy for locally advanced esophageal cancer.

Congenital diaphragmatic hernia presenting as splenic rupture in an adult

We present the case of a 66-year-old man with a congenital diaphragmatic hernia and splenic rupture. The adult presentation of congenital posterolateral diaphragmatic (Bochdalek) hernia is rare. We describe the operative approach and provide a brief review of the literature.

Distinct action of the retinoblastoma pathway on the DNA replication machinery defines specific roles for cyclin-dependent kinase complexes in prereplication complex assembly and S-phase progression

The retinoblastoma (RB) and p16ink4a tumor suppressors are believed to function in a linear pathway that is functionally inactivated in a large fraction of human cancers. Recent studies have shown that RB plays a critical role in regulating S phase as a means for suppressing aberrant proliferation and controlling genome stability. Here, we demonstrate a novel role for p16ink4a in replication control that is distinct from that of RB. Specifically, p16ink4a disrupts prereplication complex assembly by inhibiting mini-chromosome maintenance (MCM) protein loading in G1, while RB was found to disrupt replication in S phase through attenuation of PCNA function. This influence of p16ink4a on the prereplication complex was dependent on the presence of RB and the downregulation of cyclin-dependent kinase (CDK) activity. Strikingly, the inhibition of CDK2 activity was not sufficient to prevent the loading of MCM proteins onto chromatin, which supports a model wherein the composite action of multiple G1 CDK complexes regulates prereplication complex assembly. Additionally, p16ink4a attenuated the levels of the assembly factors Cdt1 and Cdc6. The enforced expression of these two licensing factors was sufficient to restore the assembly of the prereplication complex yet failed to promote S-phase progression due to the continued absence of PCNA function. Combined, these data reveal that RB and p16ink4a function through distinct pathways to inhibit the replication machinery and provide evidence that stepwise regulation of CDK activity interfaces with the replication machinery at two discrete execution points.