New experimental model of hind limb ischemia in pot-bellied pigs.

BACKGROUND: The simulation of limb ischemia in large laboratory animals is a complex and currently topical task in experimental medicine. Meanwhile, there is a demand for a reliable and effective model of limb ischemia for further testing of medicines to stimulate circulation and induce angiogenesis, gene medicines in particular. Aim of this study was to develop and experimentally test an effective method of simulation of hind limb ischemia. METHODS: Female Vietnamese pot-bellied pigs were chosen as biological models. The reproduction of the pathology was evaluated using the following methods: laser doppler flowmetry, laboratory test of venous blood, immunohistochemical reaction with antibodies against CD31, a specific marker of endothelial cells, Van Gieson's staining of muscles for presence of connective tissue and clinical observation to detect the presence of lameness in pigs. RESULTS: Laser doppler flowmetry recorded a significant decrease in the intensity of the blood circulation and a marked decrease in temperate in the operated limb. Increased lactate and creatine kinase were registered immediately after the surgery and were absent 3 or more days later. Clinical observation demonstrated presence of walking lameness. Histological and immunohistochemical methods revealed a credible increase in connective tissue area and a reduction in the number of blood vessels in the muscles, confirming the presence of ischemia. CONCLUSIONS: An effective approach to modeling limb ischemia has been developed and experimentally tested. The proposed model may be used in cardiovascular surgery and will allow further testing of new medications designed to treat ischemia of hind limbs.

Redefining the role of surgery in early small-cell lung cancer.

PURPOSE: Resection is guideline recommended in stage I small-cell lung cancer (SCLC) but not in stage II. In this stage, patients are treated with a non-surgical approach. The aim of this meta-analysis was to assess the role of surgery in both SCLC stages. Surgically treated patients were compared to non-surgical controls. Five-year survival rates were analysed. METHODS: A systematic literature search was performed on December 01, 2021 in Medline, Embase and Cochrane Library. Studies published since 2004 on the effect of surgery in SCLC were considered and assessed using ROBINS-I. We preformed I2-tests, Q-statistics, DerSimonian-Laird tests and Egger-regression. The meta-analysis was conducted according to PRISMA. RESULTS: Out of 6826 records, we identified seven original studies with a total of 15,170 patients that met our inclusion criteria. We found heterogeneity between these studies and ruled out any publication bias. Patient characteristics did not significantly differ between the two groups (p-value > 0.05). The 5-year survival rates in stage I were 47.4 ± 11.6% for the 'surgery group' and 21.7 ± 11.3% for the 'non-surgery group' (p-value = 0.0006). Our analysis of stage II SCLC revealed a significant survival benefit after surgery (40.2 ± 21.6% versus 21.2 ± 17.3%; p-value = 0.0474). CONCLUSION: Based on our data, the role of surgery in stage I and II SCLC is robust, since it improves the long-term survival in both stages significantly. Hence, feasibility of surgery as a priority treatment should always be evaluated not only in stage I SCLC but also in stage II, for which guideline recommendations might have to be reassessed.

Stage I and II Small-Cell Lung Cancer-New Challenge for Surgery.

PURPOSE: The recommended treatment for small-cell lung cancer (SCLC) currently is surgery in stage I disease. We wondered about stage II SCLC and present a meta-analysis on mean-survival of patients that underwent surgery for stage I and II compared to controls. METHODS: A systematic literature search was performed on December 01st 2021 in Medline, Embase and Cochrane Library. We considered studies published on the effect of surgery in SCLC since 2004 and assessed them using ROBINS-I. We preformed I2-tests, Q-statistics, DerSimonian-Laird tests and Egger-regression. The meta-analysis was conducted according to PRISMA. RESULTS: Out of 6826 records, seven studies with a total of 11,241 patients ('surgery group': 3911 patients; 'non-surgery group': 7330; treatment period: 1984-2015) were included. Heterogeneity between the studies was revealed in absence of any publication bias. Patient characteristics did not differ between the groups (p-value > 0.05). The mean-survival in an analysis of patients in stage I was 36.7 ± 10.8 months for the 'surgery group' and 20.3 ± 5.7 months for the 'non-surgery group' (p-value = 0.0084). A combined analysis of patients in stage I and II revealed a mean-survival of 32.0 ± 16.7 months for the 'surgery group' and 19.1 ± 6.1 months for the 'non-surgery group' (p-value = 0.0391). In a separate analysis of stage II, we were able to demonstrate a significant survival benefit after surgery (21.4 ± 3.6 versus 16.2 ± 3.9 months; p-value = 0.0493). CONCLUSION: Our meta-analysis shows a significant survival benefit after surgery not only in the recommended stage I but also in stage II SCLC. Our data suggests that both stages should be considered for surgery of early SCLC.

Postoperative Tobacco Cessation Improves Quality of Life, Lung Function and Long-Term Survival in Non-Small-Cell Lung Cancer Patients.

OBJECTIVES: About 90% of all non-small cell lung cancer (NSCLC) cases are associated with inhalative tabacco smoking. Half of patients continue smoking during lung cancer therapy. We examined the effects of postoperative smoking cessation on lung function, quality of life (QOL) and long-term survival. MATERIALS AND METHODS: In total, 641 patients, who underwent lobectomy between 2012 and 2019, were identified from our single institutional data base. Postoperatively, patients that actively smoked at the time of operation were offered a structured 'smoking cessation' program. For this retrospective analysis, two patient groups (total n = 90) were selected by pair matching. Group A (n = 60) had no postoperative tobacco smoking. Group B (n = 30) involved postoperative continued smoking. Lung function (FEV1, DLCO) and QOL ('SF-36' questionnaire) were measured 12 months postoperatively. We compared long-term outcomes using Kaplan-Meier curves. RESULTS: The mean age in group A was 62.6 ± 12.5 years and that in group B was 64.3 ± 9.7 years (p = 0.82); 64% and 62%, respectively, were male (p = 0.46). Preoperative smoking habits were similar ('pack years': group A, 47 ± 31; group B, 49 ± 27; p = 0.87). All relevant baseline characteristics we collected were similar (p > 0.05). One year after lobectomy, FEV1 was reduced by 15% in both groups (p = 0.98). Smoking cessation was significantly associated with improved DLCO (group A: 11 ± 16%; group B: -5 ± 14%; p <0.001) and QOL (vitality (VT): +10 vs. -10, p = 0.017; physical role function (RP): +8 vs. -17, p = 0.012; general health perceptions (GH): +12 vs. -5, p = 0.024). Patients who stopped smoking postoperatively had a significantly superior overall survival (median survival: 89.8 ± 6.8 [95% CI: 76.6-103.1] months vs. 73.9 ± 3.6 [95% CI: 66.9-80.9] months, p = 0.034; 3-year OS rate: 96.2% vs. 81.0%, p = 0.02; 5-year OS rate: 80.0% vs. 64.0%, p = 0.016). The hazard ratio (HR) was 2.31 [95% CI: 1.04-5.13] for postoperative smoking versus tobacco cessation. CONCLUSION: Postoperative smoking cessation is associated with improved quality of life and lung function testing. Notably, a significant increase in long-term survival rates among non-smoking NSCLC patients was observed. These findings could serve as motivation for patients to successfully complete a non-smoking program.

Closing the RCT Gap-A Large Meta-Analysis on the Role of Surgery in Stage I-III Small Cell Lung Cancer Patients.

INTRODUCTION: Despite clear guideline recommendations, surgery is not consistently carried out as part of multimodal therapy in stage I small cell lung cancer (SCLC) patients. The role of surgery in stages II and III is even more controversial. In the absence of current randomized control trials (RCT), we performed a meta-analysis comparing surgery versus non-surgical treatment in stage I to III SCLC patients. METHODS: A systematic review of the literature was conducted on 1 July 2023, focusing on studies pertaining to the impact of surgery on small cell lung cancer (SCLC). These studies were evaluated using the ROBINS-I tool. Statistical analyses, including I² tests, Q-statistics, DerSimonian-Laird tests, and Egger regression, were performed to assess the data. In addition, 5-year survival rates were analyzed. The meta-analysis was conducted according to PRISMA standards. RESULTS: Among the 6826 records identified, 10 original studies encompassing a collective cohort of 95,323 patients were incorporated into this meta-analysis. Heterogeneity was observed across the included studies, with no discernible indication of publication bias. Analysis of patient characteristics revealed no significant differences between the two groups (p-value > 0.05). The 5-year survival rates in a combined analysis of patients in stages I-III were 39.6 ± 15.3% for the 'surgery group' and 16.7 ± 12.7% for the 'non-surgery group' (p-value < 0.0001). SCLC patients in stages II and III treated outside the guideline with surgery had a significantly better 5-year survival compared to non-surgery controls (36.3 ± 20.2% vs. 20.2 ± 17.0%; p-value = 0.043). CONCLUSIONS: In the absence of current RCTs, this meta-analysis provides robust suggestions that surgery might significantly improve survival in all SCLC stages. Non-surgical therapy could lead to a shortening of life. The feasibility of surgery in non-metastatic SCLC should always be evaluated as part of a multimodal treatment.

Prognostic impact of lymph node spreading pattern in N2 NSCLC patients.

BACKGROUND: One-third of non-small cell lung cancer (NSCLC) patients are diagnosed with locally advanced disease. Long-term survival in stage IIIA/B-N2 remains poor; this may also be due to lymph node spreading pattern. Therefore, we compared the overall survival of stage IIIA/B-N2 patients with superior mediastinal lymph nodes (SML) with infracarinal- or inferior mediastinal lymph nodes (IML) and with multilevel disease (MLD). RESEARCH DESIGN AND METHODS: One-, three-and five-year survival rates were measured. Kaplan-Meier curves and Cox proportional hazards model assessed survival and were used to identify prognostic factors. RESULTS: We reviewed data of stage IIIA/B-N2 patients (n = 129) who underwent surgery for NSCLC between 2012 and 2020. Patients with SML (n = 62) were compared to ILM (n = 37) and MLD (n = 30). SML patients showed significantly better one- (SML: 95.2% vs. IML: 78.6% vs. MLD: 69.4%, p = 0.03), three- (78.8% vs. 27.7 vs. 13.3%; p = <0.001) and five-year (61.1% vs. 17.1 vs. 3%; p < 0.001) survival rates, than IML and MLD patients. Kaplan-Meier curves showed prolonged overall survival for SML patients (log-rank SML, ILM, MLD p < 0.0001). CONCLUSIONS: This study showed significantly better long-term survival of SML patients than IML and MLD patients. The long-term survival of ILM and MLD patients was equally poor.

A comparative study of four thoracic mortality scores.

BACKGROUND: The percentage of patients in resectable stages at initial diagnosis of non-small cell lung cancer (NSCLC) raises due to better screening programs. Therefore, risk prediction models are becoming more critical. Here, we validated and compared four established scoring models, the Thoracoscore, Epithor, Eurloung 2, and the simplified Eurolung 2 (2b), in their ability to predict 30-day mortality. METHODS: All consecutive patients undergoing anatomical pulmonary resection were included. The performance of the four scoring systems was assessed with Hosmer-Lemeshow goodness-of-fit test (calibration) and receiver operating characteristic (ROC) curves (discrimination). We compared the area under the curve (AUC) of the ROC curves by DeLong's method. RESULTS: A total of 624 patients underwent surgery for NSCLC at our institution between 2012 and 2018 30-day mortality was 2.2% (14 patients). The AUC for Eurolung 2 and the simplified Eurolung 2 (0.82) were greater than those of the other scoring systems, Epithor (0.71) and Thoracoscore (0.65). In addition, the DeLong analysis showed a significant superiority of Eurolung 2 and Eurolung 2b over the Thoracoscore (p = 0.04); there were no significant differences compared to Epithor. CONCLUSION: Eurolung 2 and the simplified Eurolung 2 were the favorable scoring systems for predicting 30-day mortality compared to Thoracoscore and Epithor. Therefore, we recommend using Eurolung 2 or the simplified Eurolung 2 for preoperative risk stratification.

Do skip-N2 metastases significantly impact overall survival and disease-free interval in N2 non-small-cell lung cancer patients? A multicentre analysis.

OBJECTIVES: Skip-N2 metastasis (N0N2), thus N2 metastasis in the absence of N1 metastasis, occurs in ∼20-30% of non-small-cell lung cancer patients. N0N2 patients have a better prognosis than continuous-N2 metastasis (N1N2) patients following surgery. However, this effect remains controversial. Therefore, we conducted a multicentre study to compare the long-term survival and disease-free interval (DFI) of N1N2- and N0N2 patients. METHODS: One- and 3-year survival rates were measured. Kaplan-Meier curves and a Cox proportional hazards model assessed survival and were used to identify prognostic factors for overall survival. In addition, we performed propensity score matching (PSM) to rule out confounding factors. All patients received adjuvant chemoradiation therapy according to European guidelines. RESULTS: Between January 2010 and December 2020, 218 stage IIIA/B N2 patients were included in our analysis. The Cox regression analysis revealed that N1N2 significantly influenced the overall survival rate. Before PSM, N1N2 patients showed significantly more metastatic lymph nodes (P < 0.001) and significantly larger tumours (P = 0.05). After PSM, baseline characteristics did not differ between groups. Before and after PSM, N0N2 patients showed significantly better 1- (P = 0.01; P = 0.009) and 3-year (P < 0.001) survival rates than N1N2 patients. Furthermore, N0N2 patients showed significantly longer DFI than N1N2 patients before and after PSM (P < 000.1). CONCLUSIONS: Prior and after PSM analysis, N0N2 patients were confirmed to have better survival and DFI than N1N2 patients. Our results demonstrate that stage IIIA/B N2 patients are heterogeneous and would benefit from a more precise subdivision and differential treatment.

Pulmonary metastasectomy for metastatic head and neck cancer prolongs survival significantly compared to non-surgical therapy.

OBJECTIVES: Pulmonary metastasectomy (PM) is an established procedure for selected patients with metastatic head and neck cancer (HNC). Non-surgical therapy in the form of chemo- and immunotherapy and checkpoint inhibitors and radiation therapy are also treatment options. There are no randomized controlled trials comparing PM with non-surgical therapy. Here, we retrospectively compare the long-term survival of patients, undergoing PM with patients receiving non-surgical therapy. METHODS: All HNC patients with pulmonary metastases were included, if the primary HNC was treated curatively and distant metastases, apart from the lungs were excluded. The pulmonary metastases were confirmed by biopsy as metastases of the HNC primary tumour in the non-surgical therapy group. To further clarify that PM prolonged survival, a propensity score-matched analysis was performed. RESULTS: Between January 2010 and December 2020, 62 HNC patients with isolated pulmonary metastases were included in our analysis. Thirty-three underwent PM and 29 received non-surgical therapy. Histology, tumour stage and localization of the primary HNC did not differ between groups. The number of metastases, age and ASA classification did also not differ between the groups. Patients undergoing PM showed significantly better 1- (n = 31; 93.5% vs n = 19; 65.5%; P = 0.006), 3- (n = 17; 72.2% vs n = 9; 30.4%; P = 0.004) and 5-year (n = 10; 53.4% vs n = 4; 20.0%; P = 0.001) survival rates, compared to patients receiving non-surgical therapy. CONCLUSIONS: Patients with pulmonary metastatic HNC undergoing PM had a significantly better overall survival compared to patients receiving non-surgical therapy. Therefore, selected patients should undergo PM to improve survival.

Sublobar resection without staging and lymphadenectomy for ≤2 cm Non-Small Cell Lung Cancer is no adequate therapy.

OBJECTIVE: Sublobar resection is frequently performed for Non-Small Cell Lung Cancer (NSCLC) patients with ≤2 cm nodules. Frequently, both proper staging and radical lymphadenectomy are omitted in these operations. Therefore, we decided to evaluate the number of lymph node metastases and the number of postoperative nodal upstaging in patients undergoing pulmonary resection due to NSCLC with tumors ≤2 cm at our institution. METHODS: Nodal upstaging, lymphangiosis- (L1), and hemangiosis carcinomatosa (V1) were analyzed. pN0 patients were compared to patients with postoperative nodal upstaging. One-, three, and five-year survival rates were measured. Survival was also assessed by the Kaplan-Meier method. RESULTS: 747 patients underwent surgery for NSCLC at our institution between 2012 and 2020. We retrospectively reviewed data of 236 NSCLC patients with ≤2 cm tumors. The mean tumor size was 1.4 cm ± 0.39 in our cohort. Of our patients, 14% showed a cT1a tumor, and 86% of patients cT1b. 24.0 ± 12.3 lymph nodes were dissected and analyzed per patient, and 0.7 ± 2.0 of those were affected. Of our patients, 16.1% showed L1 affection, and 7.6% a V1 affection. Lymph node involvement was diagnosed in 11(4.7%) patients preoperatively. 39(16.5%) patients were upstaged due to lymph node involvement postoperatively (p < 0.001). Upstaged patients showed significantly worse 3- (upstaged: 60.6% vs. pN0: 83.2%; p = 0.01) and 5-year (upstages: 38% vs. pN0 71.5%; p = 0.02) survival rates. CONCLUSION: 16.5% of patients with ≤2 cm NSCLC were nodal upstaged postoperatively. These results underline that lymphadenectomy and proper staging are crucial for NSCLC patients irrespective of the tumor size and the surgical approach.