Feichao Bao

Segmentectomy or lobectomy for early stage lung cancer: a meta-analysis

Early stage lung cancer is routinely treated by lobectomy whenever clinically feasible, whereas the role of segmentectomy is controversial. The purpose of this study was to investigate the benefits of segmentectomy vs lobectomy for early stage lung cancer through a meta-analysis of published data. Eligible studies were identified from MEDLINE through February 2013. The manual selection of relevant studies was based on the summary analysis. We used published hazard ratios (HRs) if available or estimates from the published survival data. Lobectomy was chosen as the reference in all HR calculations. We compared the effect of segmentectomy and lobectomy for Stage I, Stage IA, Stage IA with tumours larger than 2 cm but smaller than 3 cm in size and Stage IA with tumours of 2 cm or smaller in 22 observational studies. The HRs of overall and cancer-specific survival indicated significant benefits of lobectomy for Stage I, Stage IA and Stage IA with tumours larger than 2 cm but smaller than 3 cm at 1.20 (95% confidence interval [CI] 1.04-1.38; P = 0.011), 1.24 (95% CI 1.08-1.42; P = 0.002) and 1.41 (95% CI 1.14-1.71; P = 0.001), respectively. For tumours 2 cm or smaller, segmentectomy provided an effect equivalent to that of lobectomy (HR 1.05; 95% CI 0.89-1.24; P = 0.550). No significant publication bias was detected in any part of the analysis. These findings should be interpreted in the context of the inherent limitations of meta-analyses of retrospective studies, including the heterogeneity of patient characteristics.

Single-port video-assisted thoracoscopic right upper lobectomy using a flexible videoscope.

Single-port video-assisted thoracoscopic surgery (VATS) has recently been proposed as an innovative minimally invasive alternative to the standard three-port VATS for lobectomies, most of which are performed using a conventional rigid thoracoscope. Here, we report a single-port VATS approach for right upper lobectomy and systematic lymph node dissection using a flexible endoscope. A 61-year-old male smoker presented with a pulmonary nodule. A single-port VATS procedure was performed through a 4-cm intercostal incision using a flexible laparo-thoraco videoscope. Right upper lobectomy and systematic lymph node dissection were performed. The total operating time was 106 in. The procedure was successful and the recovery uneventful. The patients chest tube was removed on the third day, and he was discharged home on the fourth. The use of a flexible videoscope facilitated the single-port VATS procedure by avoiding interference between the videoscope and other operating instruments and providing ample space for the surgeon.

Is video-assisted thoracic surgery a versatile treatment for both simple and complex pulmonary aspergilloma?

BACKGROUND Pulmonary aspergilloma (PA) is a common fugal infectious disease mostly occurred in developing countries. This study aims to evaluate the outcomes of video-assisted thoracic surgery (VATS) treatment for simple pulmonary aspergilloma (SPA) and complex pulmonary aspergilloma (CPA). METHODS From October 2009 to March 2013, 16 patients were treated by VATS for PA in our department. The patients were divided into SPA group and CPA group. Records were retrospectively reviewed and data were collected and compared. RESULTS Patients had a median age of 52.8 years [95% confidence interval (CI): 47.8-57.9 years]. The most common symptom was hemoptysis (68.7%) in our patients. The underlying lung diseases were tuberculosis (31.1%), bronchiectasis (12.5%) and pneumatocele (6.2%). All patients received successful lesion resection by VATS, none was converted to thoracotomy. No significant difference was found in terms of sex and age. Patients with CPA tent to have larger lesion (P=0.001) and more intraoperative findings (P=0.003), they also needed longer operative time (P=0.016) and more blood loss (P=0.003). In addition, CPA patients had more volume of drainage after surgery (P=0.005), longer duration of drainage ((P=0.007) and length of stay in hospital (P=0.004). No difference was found in postoperative complications between the two groups. CONCLUSIONS SPA patients are the best candidates for VATS, but comprehensive measure should be taken for the overall benefit of CPA patients before conducting VATS.

Predictive risk factors for lymph node metastasis in patients with small size non-small cell lung cancer

BACKGROUND Accurate clinical staging of non-small cell lung cancer (NSCLC) is essential for developing an optimal treatment strategy. This study aimed to determine the predictive risk factors for lymph node metastasis, including both N1 and N2 metastases, in clinical T1aN0 NSCLC patients. METHODS We retrospectively evaluated clinical T1aN0M0 NSCLC patients who showed no radiologic evidence of lymph node metastasis, and who had undergone surgical pulmonary resection with systematic mediastinal node dissection or sampling at the First Affiliated Hospital of Zhejiang University between January 2011 and June 2013. Univariate and multivariate logistic regression analyses were performed to identify predictive factors for node metastasis. RESULTS Pathologically positive lymph nodes were found in 16.2% (51/315) of the patients. Positive N1 nodes were found in 12.4% (39/315) of the patients, and positive N2 nodes were identified in 13.0% (41/315) of the patients. Some 9.2% (29/315) of the patients had both positive N1 and N2 nodes, and 3.8% (12/315) of the patients had nodal skip metastasis. Variables of preoperative radiographic tumor size, non-upper lobe located tumors, high carcinoembryonic antigen (CEA) levels and micropapillary predominant adenocarcinoma (AC) were identified as predictors for positive N1 or N2 node multivariate analysis. CONCLUSIONS Pathologically positive lymph nodes were common in small size NSCLC patients with clinical negative lymph nodes. Therefore, preoperative staging should be performed more thoroughly to increase accuracy, especially for patients who have the larger size, non-upper lobe located, high CEA level or micropapillary predominant ACs.

Clinical, cellular, and bioinformatic analyses reveal involvement of WRAP53 overexpression in carcinogenesis of lung adenocarcinoma

Lung cancer, of which non-small cell lung cancer accounts for 80%, remains a leading cause of cancer-related mortality and morbidity worldwide. Our study revealed that the expression of WD repeat containing antisense to P53 (WRAP53) is higher in lung-adenocarcinoma specimens than in specimens from adjacent non-tumor tissues. The prevalence of WRAP53 overexpression was significantly higher in patients with tumor larger than 3.0 cm than in patients with tumor smaller than 3.0 cm. The depletion of WRAP53 inhibits the proliferation of lung-adenocarcinoma A549 and SPC-A-1 cells via G1/S cell-cycle arrest. Several proteins interacting with WRAP53 were identified through co-immunoprecipitation and liquid chromatography/mass spectrometry. These key proteins indicated previously undiscovered functions of WRAP53. These observations strongly suggested that WRAP53 should be considered a promising target in the prevention or treatment of lung adenocarcinoma.

Reply to Ng et al.

We thank Ng et al. [1] for their insightful comments on our manuscript recently published in the European Journal of Cardiothoracic Surgery [2]. In the letter, Dr Ng and colleagues provided us with an in-depth view on advancing scope technology by addressing three important aspects of video-endoscopy, which we would like to discuss in detail. The first issue mentioned was the choice of either the flexible video-endoscope or the rigid thoracoscope for single-port VATS lung resections. As mentioned in their Letter to the Editor, the flexible video-endoscope may occasionally interfere with other operating instruments, which may damage the soft scope tip; the authors also stated that a long period is required to gain sufficient familiarity with the flexible scope. Most of the thoracic surgeons— including camera assistants—in our centre have the advantages of professional skills and good experience in the aspect of bronchoscopy. Besides, we have performed lobectomy using a single-direction approach, which facilitates the procedure without repeated rotation of the scope and, during the procedure, the rigid part of the scope was at the incision, whereas the entire soft scope tip was put inside the thoracic cavity [3]. All of the above dramatically reduced the risk of damage to the soft scope tip by other instruments. Additionally, we prefer to use the flexible scope because its 5.4 mm diameter is considerably slimmer than the 10 mm of our rigid one. Another important issue is how to make best use of the single incision, as well as the three-dimensional pleural cavity space; this needs persistent innovation and improvement of surgical instruments. Apart from generally reducing their diameter, a multiple-angle stapler— facilitating the transection of vessels and bronchus—and a hollow scope that allows instruments to pass through, could make efficient use of the single incision. In addition to this, proper positioning of the instruments at different stages of the operation makes it possible to conveniently carry out the resection via a single incision [4]. The inserted instruments were controlled by magnetic anchoring and guidance system (MAGS) through a coupling with an externally held magnet [5]. Preclinical in vivomodels showed that MAGS greatly decreased surgeon workload and improved ergonomics, and was especially well suited to either single-port laparoscopic surgery or natural orifice translumenal endoscopic surgery (NOTES) [5]. We agree with Dr Ng’s team that MAGS shows promise in thoracic surgery, few research work has been done on the subject; besides, further platform development and optimization are warranted—for example, in assessing the distance at which available instrument prototypes can be used and also to develop new ones that can work in overweight patients [6]. Again, we thank Dr Ng and colleagues for their comments, from which we have learnt a great deal.

Reply to Cao et al.

We thank Cao et al. [1] for their insightful comments on our manuscript recently published in the European Journal of CardioThoracic Surgery [2]. Cao et al. addressed, in their letter to the editor, two important and controversial aspects of segmentectomy comparing with lobectomy for early stage non-small-cell lung cancer (NSCLC), which we would like to discuss in detail. The first issue emphasized by Cao et al. was the rationality of using combined overall survival (OS) and cancer-specific survival (CSS) outcomes to compare the two different surgical procedures. Our study aimed at assessing the survival difference between segmentectomy and lobectomy. We must admit that combining OS and CSS does have some shortcomings such as it may overestimate the adverse survival outcomes of segmentectomy procedures just as Cao et al. pointed out. However, the data we based our study on were divergent, with few providing CSS, whereas most of the published studies use OS to assess the two procedures. The overestimation exists in each published study which selected the patients with limited cardiopulmonary function as candidates for segmentectomy; it is inevitable for us to avoid such overestimation. Besides, a previously published paper also used combined OS and CSS to assess oncological outcomes [3]. It is insufficient to conduct meta-analysis for the comparison of segmentectomy and lobectomy exclusively based on either OS or CSS data and it would be possible in future to conduct such a meta-analysis with subgroups of OS and CSS as new suitable data are published. The other issue proposed by Cao et al. is to differentiate the intentional segmentectomy from the compromised one; recently, several studies also excluded compromised segmentectomy and aimed to compare intentional segmentectomy with lobectomy [4, 5]. Some studies, such as Tsutani et al. [6], reported the use of propensity score analysis. We agree with Cao et al. that these studies would be the future direction. However, as the data are insufficient, it is still meaningful to estimate the oncological effects of segmentectomy including both compromised and intentional procedures. We are also undertaking a prospective study aimed at selecting the optimal candidates for intentional segmentectomy. The issue that segmentectomy, especially the intentional one, or lobectomy, which is suitable for early stage NSCLC, would be long-existing until the future randomized controlled trials such as CALGB 140503 and JCOG 0802. We are grateful to Cao et al. [1] for their kind and insightful comments, and we thank them for taking the time to remark on our work.