Selection of the surgical approach for patients with cStage IA lung squamous cell carcinoma: A population-based propensity score matching analysis.

Background: This study aimed to conduct a comparative analysis of the survival rates after segmentectomy, wedge resection, or lobectomy in patients with cStage IA lung squamous cell carcinoma (SCC). Methods: We enrolled 4,316 patients who had cStage IA lung SCC from the Surveillance, Epidemiology, and End Results (SEER) database. The Cox proportional hazards model was conducted to recognize the potential risk factors for overall survival (OS) and lung cancer-specific survival (LCSS). To eliminate potential biases of included patients, the propensity score matching (PSM) method was used. OS and LCSS rates were compared among three groups stratified according to tumor size. Results: Kaplan-Meier analyses revealed no statistical differences in the rates of OS and LCSS between wedge resection (WR) and segmentectomy (SG) groups for patients who had cStage IA cancers. In patients with tumors ≤ 1 cm, LCSS favored lobectomy (Lob) compared to segmentectomy (SG), but a similar survival rate was obtained for wedge resection (WR) and lobectomy (Lob). For patients with tumors sized 1.1 to 2 cm, lobectomy had improved OS and LCSS rates compared to the segmentectomy or wedge resection groups, with the exception of a similar OS rate for lobectomy and segmentectomy. For tumors sized 2.1 to 3 cm, lobectomy had a higher rate of OS or LCSS than wedge resection or segmentectomy, except that lobectomy conferred a similar LCSS rate compared to segmentectomy. Multivariable analyses showed that patients aged ≥75 and tumor sizes of >2 to ≤3 cm were potential risk factors for OS and LCSS, while lobectomy and first malignant primary indicator were considered protective factors. The Cox proportional analysis also confirmed that male patients aged ≥65 to <75 were independent prognostic factors that are indicative of a worse OS rate. Conclusions: The tumor size can influence the surgical procedure recommended for individuals with cStage IA lung SCC. For patients with tumors ≤1 cm, lobectomy is the recommended approach, and wedge resection or segmentectomy might be an alternative for those who cannot tolerate lobectomy if adequate surgical margin is achievable and enough nodes are sampled. For tumors >1 to ≤3 cm, lobectomy showed better survival outcomes than sublobar resection. Our findings require further validation by randomized controlled trial (RCT) or other evidence.

[Clinical Application of Vectorial Localization of Peripheral Pulmonary Nodules Guided by Electromagnetic Navigation Bronchoscopy in Thoracic Surgery].

BACKGROUND: More patients with pulmonary nodules are being referred to thoracic surgeons under the increasing use of computed tomography scans (CT). Impalpable peripheral subpleural solitary pulmonary nodules are difficult to be localized by video assisted thoracic surgery. Although some common techniques including CT-guided puncture positioning and electromagnetic navigation bronchoscopy (ENB)-guided methylene blue staining positioning, can bring good results in positioning, there are still some complications such as pneumothorax, hemorrhage and inaccurate positioning. Vectorial localization guided by electromagnetic navigational bronchoscopy followed by thoracoscopic resection is a novel alternative technique by us firstly for definitive diagnosis, which can avoid the possible injury of pleural or enlargement of the location area, providing some guidance for ENB-guided location technology. The main objective of this study was to evaluate the feasibility and our initial experience of vectorial localization guided by electromagnetic navigation followed by video-assisted thoracoscopic pulmonary solitary nodules resection. METHODS: We retrospectively analyzed 22 cases who undergoing vectorial localization of peripheral pulmonary lesion guided by electromagnetic navigation prior to video assisted lung resection, and characteristics and intraoperative outcomes were explored. RESULTS: Twenty-two nodules of twenty-two patients were all localized by this method successfully with an average location time (17.5±4.2) min. The average nodule size was (11.0±3.6) mm. The distance between the locatable guide probe (LG) and lesion on the electromagnetic navigation bronchoscopy screen was (14.5±10.1) mm. The distance between the lesion and probe mark on the dissected specimen was (15.3±11.0) mm. There was no displacement of any case. No conversion to thoracotomy was found. And there were no adverse events during the localization and operation procedure. Length of hospital stay was (3.8±1.2) d and the operative mortality was 0.0%. Malignant lesions were found in 19 patients and they were all completely resected with negative microscopic margins. CONCLUSIONS: Our initial experience with vectorial localization of peripheral pulmonary lesion guided by electromagnetic navigation and minimally invasive resection proved that this technique was an alternative accurate and safe way for small pulmonary nodules. Thoracic surgeons should further investigate this method and apply it to clinical practice.

Learning curve for robot-assisted lobectomy of lung cancer.

BACKGROUND: Robotic lobectomy is widely used for lung cancer treatment. So far, few studies have been performed to systematically analyze the learning curve. Our purpose is to define the learning curve to provide a training guideline of this technique. METHODS: A total of 208 consecutive patients with primary lung cancer who underwent robotic-assisted lobectomy by our surgical team were enrolled in this study. Baseline information and postoperative outcomes were collected. Learning curves were then analyzed using the cumulative sum (CUSUM) method. Patients were divided into three groups according to the cut-off points of the learning curve. Intraoperative characteristics and short-term outcomes were compared among the three groups. RESULTS: CUSUM plots revealed that the docking time, console time and total surgical time in patients were 20, 34 and 32 cases, respectively. Comparison of the surgical time among the 3 phases revealed that the total surgical time (197.03±27.67, 152.61±21.07, 141.35±29.11 min, P<0.001), console time (150.97±26.13, 103.89±18.04, 97.49±24.80 min, P<0.001) and docking time (13.53±2.08, 11.95±1.10, 11.89±1.49 min, P<0.001) were decreased significantly. Estimated blood loss differed among groups (90.63±45.41, 87.63±59.84, 60.29±28.59 mL, P=0.001) and was associated with shorter operative time. There was no conversion or 30-day mortality. No significant differences were observed among other clinic-pathological characteristics among the groups. CONCLUSIONS: For a surgeon, the learning time of robotic lobectomy was in the 32th operation. For a bedside assistant, at least 20 cases were required to achieve the level of optimal docking.

Predictive value of a prognostic model based on pathologic features in lung invasive adenocarcinoma.

OBJECTIVES: Tumor spread through air spaces (STAS) was recently reported as a novel risk factor for the prognosis of patients with resected lung adenocarcinoma that indicates invasive tumor behavior. The purpose of this study was to build a prognostic model consisting of STAS and other pathologic features including visceral pleural invasion (VPI), vascular invasion (VI) and histological subtype (HS) in lung invasive adenocarcinoma. MATERIALS AND METHODS: A total of 289 patients with resected lung invasive adenocarcinomas ≤4 cm were analyzed retrospectively to evaluate the potential prognostic value of STAS, VPI, VI and HS for recurrence-free survival (RFS) and overall survival (OS). RESULTS: STAS was observed in 143 patients (49.5%). Univariate and multivariate analysis showed that STAS, VPI, VI and HS were significant prognostic factors for poorer RFS and OS. Thus, a prognostic model including STAS, VPI, VI and HS was built using the results of the multivariate analysis. Nomograms were developed to predict the 5-year RFS and OS. The concordance index (C-index) of the prognostic model was 0.8122 for predicting 5-year RFS and 0.8539 for predicting 5-year OS in the internal validation. Moreover, the calibration curves for the 5-year RFS and OS showed that the nomograms were calibrated well. In addition, a similar predicted capability of the prognostic model was observed in the validation cohort. CONCLUSION: STAS, VPI, VI and HS were significant prognostic factors for poorer RFS and OS. The prognostic model including STAS, VPI, VI and HS could effectively predict prognosis.

Impact of visceral pleural invasion on the association of extent of lymphadenectomy and survival in stage I non-small cell lung cancer.

Visceral pleural invasion (VPI) has been identified as an adverse prognostic factor for non-small cell lung cancer (NSCLC). Accurate nodal staging for NSCLC correlates with improved survival, but it is unclear whether tumors with VPI require a more extensive lymph nodes (LNs) dissection to optimize survival. We aimed to evaluate the impact of VPI status on the optimal extent of LNs dissection in stage I NSCLC, using the Surveillance, Epidemiology, and End Results (SEER) database. We identified 9297 surgically treated T1-2aN0M0 NSCLC patients with at least one examined LNs. Propensity score matching was conducted to balance the baseline clinicopathologic characteristics between the VPI group and non-VPI group. Log-rank tests along with Cox proportional hazards regression methods were performed to evaluate the impact of extent of LNs dissection on survival. VPI was correlated with a significant worse survival, but there was no significant difference in survival rate between PL1 and PL2. Patients who underwent sublobectomy had slightly decreased survival than those who underwent lobectomy. Pathologic LNs examination was significantly correlated with survival. Examination of 7-8 LNs and 14-16 LNs conferred the lowest hazard ratio for T1-sized/non-VPI tumors (stage IA) and T1-sized/VPI tumors (stage IB), respectively. The optimal extent of LNs dissection varied by VPI status, with T1-sized/VPI tumors (stage IB) requiring a more extensive LNs dissection than T1-sized/non-VPI tumors (stage IA). These results might provide guidelines for surgical procedure in early stage NSCLC.