Selection of the Most Suitable Culture Medium for Patient-Derived Lung Cancer Organoids.

INTRODUCTION: Patient-derived organoids have emerged as a promising in vitro model for precision medicine, particularly in cancer, but also in noncancer-related diseases. However, the optimal culture medium for culturing patient-derived lung organoids has not yet been agreed upon. This study aimed to shed light on the optimal selection of a culture media for developing studies using patient-derived lung organoids. METHODS: Tumor and normal paired tissue from 71 resected non-small cell lung cancer patients were processed for organoid culture. Lung cancer organoids (LCOs) were derived from tumor tissue and normal lung organoids (LNOs) from nonneoplastic lung tissue. Three different culture media were compared: permissive culture medium (PCM), limited culture medium (LCM), and minimum basal medium (MBM). We assessed their effectiveness in establishing organoid cultures, promoting organoid growth and viability, and compared their differential phenotypic characteristics. RESULTS: While PCM was associated with the highest success rate and useful for long-term expansion, MBM was the best option to avoid normal organoid overgrowth in the organoid culture. The density, size, and viability of LNOs were reduced using LCM and severely affected with MBM. LNOs cultured in PCM tend to differentiate to bronchospheres, while alveolosphere differentiation can be observed in those cultured with LCM. The morphological phenotype of LCO was influenced by the culture media of election. Mesenchymal cell overgrowth was observed when LCM was used. CONCLUSION: This work highlights the importance of considering the research objectives when selecting the most suitable culture medium for growing patient-derived lung organoids.

Characterization of the MicroRNA Cargo of Extracellular Vesicles Isolated from a Pulmonary Tumor-Draining Vein Identifies miR-203a-3p as a Relapse Biomarker for Resected Non-Small Cell Lung Cancer.

In resected non-small cell lung cancer (NSCLC), post-surgical recurrence occurs in around 40% of patients, highlighting the necessity to identify relapse biomarkers. An analysis of the extracellular vesicle (EV) cargo from a pulmonary tumor-draining vein (TDV) can grant biomarker identification. We studied the pulmonary TDV EV-miRNAome to identify relapse biomarkers in a two-phase study (screening and validation). In the screening phase, a 17-miRNA relapse signature was identified in 18 selected patients by small RNAseq. The most expressed miRNA from the signature (EV-miR-203a-3p) was chosen for further validation. Pulmonary TDV EV-miR-203a-3p was studied by qRT-PCR in a validation cohort of 70 patients, where it was found to be upregulated in relapsed patients (p = 0.0194) and in patients with cancer spread to nearby lymph nodes (N+ patients) (p = 0.0396). The ROC curve analysis showed that TDV EV-miR-203a-3p was able to predict relapses with a sensitivity of 88% (AUC: 0.67; p = 0.022). Moreover, patients with high TDV EV-miR-203a-3p had a shorter time to relapse than patients with low levels (43.6 vs. 97.6 months; p = 0.00703). The multivariate analysis showed that EV-miR-203a-3p was an independent, predictive and prognostic post-surgical relapse biomarker. In conclusion, pulmonary TDV EV-miR-203a-3p is a promising new relapse biomarker for resected NSCLC patients.

Evaluation of a Powered Vascular Stapler in Video-Assisted Thoracic Surgery Lobectomy.

BACKGROUND: A narrow-profile powered vascular stapler (PVS) was developed to provide superior access and precise staple placement in thoracic procedures. The objective of this study was to determine if the PVS would yield an equivalent rate of hemostatic interventions compared with standard of care (SOC) staplers in video-assisted thoracoscopic surgery lobectomy. MATERIALS AND METHODS: A randomized, controlled, multicenter study was conducted comparing PVS with SOC staplers in lobectomies performed for non-small cell lung cancer. The primary performance endpoint was the incidence of intraoperative hemostatic interventions, and the primary safety endpoint was the frequency of postoperative bleeding-related interventions. RESULTS: A total of 98 subjects participated in the SOC group and 103 in the PVS group. Rates of intraoperative hemostatic interventions were 5.3% and 8.3% for the SOC and PVS groups, respectively. These rates were not statistically different (P = 0.137), although the upper bound of the 95% confidence interval for the difference in intervention rates between PVC and SOC exceeded a predefined 3% criterion for equivalence. Simple compressions were performed more frequently in the PVS subjects, which accounted for the higher intervention rate in this group. Postoperative interventions for bleeding were required in one SOC subject (1.0%) and one subject from the PVS group (0.9%). Procedure-related adverse events occurred in 21 (21.9%) SOC subjects and 23 (21.9%) PVS subjects, with no adverse events related to use of the study devices. CONCLUSIONS: The PVS exhibited similar overall safety and effectiveness to SOC staplers in video-assisted thoracoscopic surgery lobectomy.

Multi-level immune response network in mild-moderate Chronic Obstructive Pulmonary Disease (COPD).

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is associated with an abnormal pulmonary and systemic immune response to tobacco smoking. Yet, how do immune cells relate within and between these two biological compartments, how the pulmonary infiltrate influences the lung transcriptome, and what is the role of active smoking vs. presence of disease is unclear. METHODS: To investigate these questions, we simultaneously collected lung tissue and blood from 65 individuals stratified by smoking habit and presence of the disease. The immune cell composition of both tissues was assessed by flow cytometry, whole lung transcriptome was determined with Affymetrix arrays, and we used Weighted Gene Co-expression Network Analysis (WGCNA) to integrate results. RESULTS: Main results showed that: (1) current smoking and the presence of COPD were both independently associated with a reduction in the proportion of lung T cells and an increase of macrophages, specifically those expressing CD80 + CD163+; (2) changes in the proportion of infiltrating macrophages, smoking status or the level of airflow limitation were associated to different WGCNA modules, which were enriched in iron ion transport, extracellular matrix and cilium organization gene ontologies; and, (3) circulating white blood cells counts were correlated with lung macrophages and T cells. CONCLUSIONS: Mild-moderated COPD lung immune infiltrate is associated with the active smoking status and presence of disease; is associated with changes in whole lung tissue transcriptome and marginally reflected in blood.

Progenitor cell mobilisation and recruitment in pulmonary arteries in chronic obstructive pulmonary disease.

BACKGROUND: Pulmonary vascular abnormalities are a characteristic feature of chronic obstructive pulmonary disease (COPD). Cigarette smoking is the most important risk factor for COPD. It is believed that its constant exposure triggers endothelial cell damage and vascular remodelling. Under pathological conditions, progenitor cells (PCs) are mobilized from the bone marrow and recruited to sites of vascular injury. The aim of the study was to investigate whether in COPD the number of circulating PCs is related to the presence of bone marrow-derived cells in pulmonary arteries and the association of these phenomena to both systemic and pulmonary endothelial dysfunction. METHODS: Thirty-nine subjects, 25 with COPD, undergoing pulmonary resection because of a localized carcinoma, were included. The number of circulating PCs was assessed by flow cytometry using a triple combination of antibodies against CD45, CD133 and CD34. Infiltrating CD45+ cells were identified by immunohistochemistry in pulmonary arteries. Endothelial function in systemic and pulmonary arteries was measured by flow-mediated dilation and adenosine diphosphate-induced vasodilation, respectively. RESULTS: COPD patients had reduced numbers of circulating PCs (p < 0.05) and increased numbers of CD45+ cells (< 0.05) in the pulmonary arterial wall than non-COPD subjects, being both findings inversely correlated (r = - 0.35, p < 0.05). In pulmonary arteries, the number of CD45+ cells correlated with the severity of vascular remodelling (r = 0.4, p = 0.01) and the endothelium-dependent vasodilation (r = - 0.3, p = 0.05). Systemic endothelial function was unrelated to the number of circulating PCs and changes in pulmonary vessels. CONCLUSION: In COPD, the decrease of circulating PCs is associated with their recruitment in pulmonary arteries, which in turn is associated with endothelial dysfunction and vessel remodelling, suggesting a mechanistic link between these phenomena. Our findings are consistent with the notion of an imbalance between endothelial damage and repair capacity in the pathogenesis of pulmonary vascular abnormalities in COPD.

Clinical significance of long non-coding RNA HOTTIP in early-stage non-small-cell lung cancer.

BACKGROUND: HOTTIP, a long non-coding RNA located in the HOXA cluster, plays a role in the patterning of tissues with mesodermal components, including the lung. Overexpression of HOXA genes, including HOTTIP, has been associated with a more aggressive phenotype in several cancers. However, the prognostic impact of HOTTIP has not yet been explored in non-small-cell lung cancer (NSCLC). We have correlated HOTTIP expression with time to relapse (TTR) and overall survival (OS) in early-stage NSCLC patients. METHODS: Ninety-nine early-stage NSCLC patients who underwent surgical resection in our center from June 2007 to November 2013 were included in the study. Mean age was 66; 77.8% were males; 73.7% had stage I disease; and 55.5% had adenocarcinoma. A validation data set comprised stage I-II patients from The Cancer Genome Atlas (TCGA) Research Network. RESULTS: HOTTIP was expressed in all tumor samples and was overexpressed in squamous cell carcinoma (p = 0.007) and in smokers (p = 0.018). Patients with high levels of HOTTIP had shorter TTR (78.3 vs 58 months; p = 0.048) and shorter OS (81.2 vs 61 months; p = 0.023) than those with low levels. In the multivariate analysis, HOTTIP emerged as an independent prognostic marker for TTR (OR: 2.05, 95%CI: 1-4.2; p = 0.05), and for OS (OR: 2.31, 95%CI: 1.04-5.1; p = 0.04). HOTTIP was validated as a prognostic marker for OS in the TCGA adenocarcinoma cohort (p = 0.025). Moreover, we identified a 1203-mRNA and a 61-miRNA signature that correlated with HOTTIP expression. CONCLUSIONS: The lncRNA HOTTIP can be considered a prognostic biomarker in early-stage NSCLC.

N2 disease in non-small-cell lung cancer: straight to surgery?

The correct treatment for patients with non-small-cell lung cancer and ipsilateral mediastinal involvement (N2) remains a challenge. The heterogeneity of this group of patients has been shown, as well as many different prognostic factors, that will determine a specific management to each of them. Although the standard treatment is based on a multimodality therapy consisting of chemotherapy, radiotherapy and surgery, surgery is not always indicated. The selection of patients who are going to be operated, reminds being a key point of the treatment of this disease. Recent reports on operable N2 disease have been reviewed by our group in order to discuss surgery indications and when to bring it about, with the possibility to go straight to surgery.

Is it appropriate to perform video-assisted thoracoscopic surgery for advanced lung cancer?

Video-assisted thoracoscopic surgery (VATS) has showed benefits in terms of pain, hospital stay and accomplishment of adjuvancy therapy versus open surgery in early stage of non-small-cell lung cancer. Over the last years, the indication of VATS technique has been expanded to advanced lung cancer. In this article, we discuss the definition of VATS and advanced lung cancer, and the safety and feasibility of VATS technique for the resection of advanced tumors.

Characterization, localization and comparison of c-Kit+ lung cells in never smokers and smokers with and without COPD.

BACKGROUND: c-Kit + lung stem cells have been described in the human healthy lung. Their potential relation with smoking and/or chronic obstructive pulmonary disease (COPD) is unknown. METHODS: We characterized and compared c-Kit+ cells in lung tissue of 12 never smokers (NS), 15 smokers with normal spirometry (S) and 44 COPD patients who required lung resectional surgery. Flow cytometry (FACS) was used to characterize c-Kit+ cells in fresh lung tissue disaggregates, and immunofluorescence (IF) for further characterization and to determine their location in OCT- embedded lung tissue. RESULTS: We identified 4 c-Kit+ cell populations, with similar proportions in NS, S and COPD: (1) By FACS, c-Kithigh/CD45+ cells (4.03 ± 2.97% (NS), 3.96 ± 5.30% (S), and 5.20 ± 3.44% (COPD)). By IF, these cells were tryptase+ (hence, mast cells) and located around the airways; (2) By IF, c-Kitlow/CD45+/triptase- (0.07 ± 0.06 (NS), 0.03 ± 0.02 (S), and 0.06 ± 0.07 (COPD) cells/field), which likely correspond to innate lymphoid cells; (3) By FACS, c-Kitlow/CD45-/CD34+ (0.95 ± 0.84% (NS), 1.14 ± 0.94% (S) and 0.95 ± 1.38% (COPD)). By IF these cells were c-Kitlow/CD45-/CD31+, suggesting an endothelial lineage, and were predominantly located in the alveolar wall; and, (4) by FACS, an infrequent c-Kitlow/CD45-/CD34- population (0.09 ± 0.14% (NS), 0.08 ± 0.09% (S) and 0.08 ± 0.11% (COPD)) compatible with a putative lung stem cell population. Yet, IF failed to detect them and we could not isolate or grow them, thus questioning the existence of c-Kit+ lung stem-cells. CONCLUSIONS: The adult human lung contains a mixture of c-Kit+ cells, unlikely to be lung stem cells, which are independent of smoking status and/or presence of COPD.

Completion pneumonectomy: a valuable option for lung cancer recurrence or new primaries.

BACKGROUND: The preoperative selection of patients with lung cancer recurrence remains a major clinical challenge. Several aspects of this kind of surgery are still insufficiently evidence-based, with only a few series with more than 50 patients. METHODS: A retrospective study on 29 patients who underwent a completion pneumonectomy for postoperative lung cancer recurrence or new primary was done in the period between October 2004 and December 2015. Inclusion criteria include complete (R0) first and second resections, histologically proven recurrent or new malignancy, complete pathohistological report after both operations, and exact data about the treatment outcome at the time of the last contact with patients or their families. RESULTS: There were 25 (86.2%) males and 4 (13.8%) females (M:F 6.2:1). In 13/29 patients, the interval between the first and second operations was less than 2 years, while in the remaining 16 patients, it was longer than 2 years. Concerning the operative stage distribution, stage I was more frequent after the first operation (44.8 vs. 22%), while stage III was dominant after the second operation (40.7 vs. 10.3%). The same tumor histology after the first and second operations existed in 24 (82.8%) patients. Adjuvant treatment was given to 53.6% of patients after the first and to 45.5% of patients after the second operation. The overall 5-year survival was 30%, median survival being 35 ± 16.9 months (1.896, 68.104 95% CI). A median survival of patients in post-surgery stage I after re-do surgery was better in comparison with that in higher stages (35 ± 22.6 vs.17.2 ± 15.1 vs. 21 ± 6.7 months, p > 0.05). Patients with the same tumor type at both operations lived significantly longer (median survival 48 ± 21.5 vs. 7.7 ± 1.9 months) than patients with different tumor histology after the second operation. Patients under 60 years (42.9%) lived longer than patients older than 60 years (median survival 69 ± 4.5 vs. 17.2 ± 14.3 months). The Cox regression analysis revealed only the disease stage at first operation and the same/different tumor histology as significant prognostic factors. One patient died from cardiac insufficiency caused by bronchopleural fistula (3.4% operative mortality). Operative morbidity was 34.4%. CONCLUSION: Completion pneumonectomy may be a reasonable option for postoperative lung cancer recurrence or new primaries only in carefully selected patients, in whom the potential oncological benefits overweigh the surgical risk.

Mediastinal staging by videomediastinoscopy in clinical N1 non-small cell lung cancer: a prospective multicentre study.

A quarter of patients with clinical N1 (cN1) non-small cell lung cancer (NSCLC) based on positron emission tomography-computed tomography (PET-CT) imaging have occult mediastinal nodal involvement (N2 disease). In a prospective study, endosonography alone had an unsatisfactory sensitivity (38%) in detecting N2 disease. The current prospective multicentre trial investigated the sensitivity of preoperative mediastinal staging by video-assisted mediastinoscopy (VAM) or VAM-lymphadenectomy (VAMLA).Consecutive patients with operable and resectable (suspected) NSCLC and cN1 after PET-CT imaging underwent VAM(LA). The primary study outcome was sensitivity to detect N2 disease. Secondary endpoints were the prevalence of N2 disease, negative predictive value (NPV) and accuracy of VAM(LA).Out of 105 patients with cN1 on imaging, 26% eventually developed N2 disease. Invasive mediastinal staging with VAM(LA) had a sensitivity of 73% to detect N2 disease. The NPV was 92% and accuracy 93%. Median number of assessed lymph node stations during VAM(LA) was 4 (IQR 3-5), and in 96%, at least three stations were assessed.VAM(LA) has a satisfactory sensitivity of 73% to detect mediastinal nodal disease in cN1 lung cancer, and could be the technique of choice for pre-resection mediastinal lymph node assessment in this patient group with a one in four chance of occult-positive mediastinal nodes after negative PET-CT.

Assessment of a Combined Panel of Six Serum Tumor Markers for Lung Cancer.

RATIONALE: We have previously identified six serum tumor markers (TMs) (carcinoembryonic antigen, carbohydrate antigen 15.3, squamous cell carcinoma-associated antigen, cytokeratin-19 fragment, neuron-specific enolase, and pro-gastrin-releasing peptide) related to the presence of lung cancer (LC). OBJECTIVES: To validate their individual performance in an independent cohort, and to explore if their combined assessment (≥1 abnormal TM value) is a more accurate marker for LC presence. METHODS: We determined these six TMs in 3,144 consecutive individuals referred to our institution by their primary care physician because of the clinical suspicion of LC. MEASUREMENTS AND MAIN RESULTS: LC was excluded in 1,316 individuals and confirmed in 1,828 patients (1,563 with non-small cell LC and 265 with small cell LC). This study validated the previously reported performance of each individual TM. We also showed that their combined assessment (≥1 abnormal TM) had a better sensitivity, specificity, negative predictive value, and positive predictive value (88.5, 82, 83.7, and 87.3%, respectively) than each TM considered individually and that it increased the diagnostic performance (area under the curve) of a clinical model that included tumor size, age, and smoking status. In patients with radiographic nodules less than 3 cm, the negative predictive value of the TM panel was 71.8%, hence providing some support for a more conservative diagnostic approach. Finally we identified two TMs (neuron-specific enolase and pro-gastrin-releasing peptide) that differentiate the risk of non-small cell LC from that of small cell LC. CONCLUSIONS: The combined assessment of a panel of six serum TMs is a more accurate marker for LC presence than these same TMs considered individually. The potential of these TMs in the diagnostic and screening settings deserves further research.

NKX2-1 expression as a prognostic marker in early-stage non-small-cell lung cancer.

BACKGROUND: NKX2-1, a key molecule in lung development, is highly expressed in non-small cell lung cancer (NSCLC), particularly in lung adenocarcinoma (ADK), where it is a diagnostic marker. Studies of the prognostic role of NKX2-1 in NSCLC have reported contradictory findings. Two microRNAs (miRNAs) have been associated with NKX2-1: miR-365, which targets NKX2-1; and miR-33a, which is downstream of NKX2-1. We have examined the effect of NKX2-1, miR-365 and miR-33a on survival in a cohort of early-stage NSCLC patients and in sub-groups of patients classified according to the mutational status of TP53, KRAS, and EGFR. METHODS: mRNA and miRNA expression was determined using TaqMan assays in 110 early-stage NSCLC patients. TP53, KRAS, and EGFR mutations were assessed by Sanger sequencing. RESULTS: NKX2-1 expression was upregulated in never-smokers (P = 0.017), ADK (P < 0.0001) and patients with wild-type TP53 (P = 0.001). A negative correlation between NKX2-1 and miR-365 expression was found (ρ = -0.287; P = 0.003) but there was no correlation between NKX2-1 and miR-33a expression. Overall survival (OS) was longer in patients with high expression of NKX2-1 than in those with low expression (80.8 vs 61.2 months (P = 0.035), while a trend towards longer OS was observed in patients with low miR-365 levels (P = 0.07). The impact of NKX2-1 on OS and DFS was higher in patients with neither TP53 nor KRAS mutations. Higher expression of NKX2-1 was related to higher OS (77.6 vs 54 months; P = 0.017) and DFS (74.6 vs 57.7 months; P = 0.006) compared to low expression. The association between NKX2-1 and OS and DFS was strengthened when the analysis was limited to patients with stage I disease (P = 0.005 and P=0.003 respectively). CONCLUSIONS: NKX2-1 expression impacts prognosis in early-stage NSCLC patients, particularly in those with neither TP53 nor KRAS mutations.

Impact of inappropriate lymphadenectomy on lung metastasectomy for patients with metastatic colorectal cancer.

PURPOSE: To evaluate the characteristics of lymph node assessment in the Spanish Colorectal Metastasectomy Registry (GECMP-CCR) and to analyze and compare the survival of patients with pathological absence or presence of lymph node metastases (LNM) with the survival of those with uncertain lymph node status (uLNs). METHODS: A total of 522 patients with lung metastases from colorectal carcinoma were prospectively registered from 2008 to 2010. To confirm the pathologic absence of LNM, systematic nodal dissection or systematic sampling was required, or the lymph node status was coded as uncertain. Disease-specific survival and disease-free survival were calculated by the Kaplan-Meier method with the log-rank test for comparisons. RESULTS: Lymphadenectomy was performed in 250 (48%) patients. LNM was found in 25 (10%) of the patients who had lymph node assessment done. The 3- and 5-year disease-specific survival rates according to lymph node status were 73.5 and 58.3% in the absence of LNM, 50.5 and 24.8% when LNM was confirmed, and 69 and 44% for those with uLNs, respectively (p = 0.006). CONCLUSIONS: The presence of LNM and uLNs is associated with an increased risk of death. The association of nodal assessment at the time of metastasectomy to identify LNM helps us to refine the postoperative prognosis; therefore, its impact should be properly studied in a prospective clinical trial.

Experience with the Nuss technique for the treatment of Pectus Excavatum in Spanish Thoracic Surgery Departments.

INTRODUCTION: Although the Nuss technique revolutionized the surgical treatment of pectus excavatum, its use has not become widespread in our country. The aim of this study was to analyze the current use of this technique in a sample of Thoracic Surgery Departments in Spain. METHODS: Observational rectrospective multicentric study analyzing the main epidemiological aspects and clinical results of ten years experience using the Nuss technique. RESULTS: Between 2001 and 2010 a total of 149 patients were operated on (mean age 21.2 years), 74% male. Initial aesthetic results were excellent or good in 93.2%, mild in 4.1% and bad in 2.7%. After initial surgery there were complications in 45 patients (30.6%). The most frequent were wound seroma, bar displacement, stabilizer break, pneumothorax, haemothorax, wound infection, pneumonia, pericarditis and cardiac tamponade that required urgent bar removal. Postoperative pain appeared in all patients. In 3 cases (2%) it was so intense that it required bar removal. After a mean follow-up of 39.2 months, bar removal had been performed in 72 patients (49%), being difficult in 5 cases (7%). After a 1.6 year follow-up period good results persisted in 145 patients (98.7%). CONCLUSION: Nuss technique in adults has had good results in Spanish Thoracic Surgery Departments, however its use has not been generalized. The risk of complications must be taken into account and its indication must be properly evaluated. The possibility of previous conservative treatment is being analyzed in several departments at present.

Prospective Clinical Study to Evaluate Clinical Performance of a Powered Surgical Stapler in Video-assisted Thoracoscopic Lung Resections.

Video-assisted thoracic surgery (VATS) research often focuses on postoperative air leak, with special consideration for prolonged air leak. There is limited clinical data regarding how stapling devices might affect performance and postoperative outcomes, including air leak. This prospective research evaluates intraoperative and postoperative data associated with VATS, using a new surgical stapling device, in two different geographic regions (the U.S. and Europe). A total of 226 subjects across 10 institutions were enrolled in this study. The primary endpoint was occurrence and duration of postoperative air leaks, including prolonged air leak. Additional data collected included intraoperative details and postoperative outcomes. Prolonged air leak occurred in 22 subjects (10.3%) across procedures (152 lobectomies, 63 wedge resections, and 11 occurrences of wedge resection plus lobectomy). There were no significant differences in occurrence or duration of PAL between the U.S. and Europe. Regional differences were observed for intraoperative leak testing and cartridge selection relative to tissue type. Despite differences in surgical technique between continents, no major or significant difference in air leak or other clinical outcome was detected. Additional research is needed to characterize optimal cartridge selection to tissue properties and how these may potentially impact clinical outcomes.

Robotic Lobectomy Learning Curve Has Better Clinical Outcomes than Videothoracoscopic Lobectomy.

Introduction: The robotic-assisted (RATS) lobectomy learning curve is usually measured compared to an established videothoracoscopic (VATS) surgery program. The objective of our study is to compare the learning curves of both techniques. Methods: We performed an intention-to-treat analysis comparing the RATS vs. VATS lobectomies. Surgical time, conversions, complications, number of lymph nodes (LNs) and lymph node stations harvested, chest drainage duration, length of stay, readmissions, and 90-day mortality were compared between both groups. The learning curve was assessed using the CUSUM method. Results: RATS cases (30) and VATS cases (35) displayed no significant differences. The RATS learning curve was completed after 23 procedures while the VATS curve required 28 interventions. Complications appeared in four RATS procedures and in eight VATS patients. No differences in the number of LNs and harvested LN stations were reported. Four patients were readmitted in the RATS group, and eight in the VATS group. No 90-day postoperative mortality was observed in either group. The RATS group reported fewer chest tube days (3 (2-5) vs. 5 (4-5.8), p = 0.005) and hospital days (4 (3-6) vs. 5 (4-6), p = 0.023). Conclusions: The RATS curve appears shorter than the VATS curve. RATS lobectomies resulted in reduced chest tube duration and length of stay during the learning time period.

Low miR-145 and high miR-367 are associated with unfavourable prognosis in resected nonsmall cell lung cancer.

The transcription factors SRY-related HMG box (SOX)2 and octamer-binding transcription factor (OCT)4 regulate the expression of the miR-302-367 cluster. miR-145 regulates SOX2 and OCT4 translation and p53 regulates miR-145 expression. We analysed the expression of the miR-302-367 cluster and miR-145 and the mutational status of p53 in resected nonsmall cell lung cancer (NSCLC) patients and correlated results with time to relapse (TTR). Tumour and paired normal tissue samples were obtained from 70 NSCLC patients. MicroRNA expression was assessed with TaqMan MicroRNA Assays. p53 exons 5 to 8 were sequenced. miR-145 was downregulated (p<0.0001) and miR-367 was upregulated (p<0.0001) in tumour compared with normal tissue. Mean TTR was 18.4 months for patients with low miR-145 levels and 28.2 months for those with high levels (p=0.015). Mean TTR was 29.1 months for patients with low miR-367 levels and 23.4 months for those with high levels (p=0.048). TTR was shorter for patients with both unfavourable variables (p=0.009). Low miR-145 expression (p=0.049), the combination of unfavourable microRNA levels (p=0.02) and the combination of low miR-145 with p53 mutations (p=0.011) were independent markers of shorter TTR. In conclusion, miR-145 and miR-367 expression could be novel markers for relapse in surgically treated NSCLC. p53 may play a role in modulating miR-145 expression in NSCLC.