P-OGC29 Pathological response profiles of FLOT and ECX neoadjuvant chemotherapy in oesophageal adenocarcinoma

Background 70% of patients undergoing neo-adjuvant ECX chemotherapy for adenocarcinoma of the oesophagus, show little to know response in their primary tumour (Mandard 4,5). However, among these patients, those who have a complete nodal response (cN+ to ypN0) have equivalent survival to those with Mandard 1,2,3 tumours. FLOT chemotherapy has shown a survival advantage to ECX, however, rates of primary tumour response and nodal response are yet to be the focus of published study. Methods Retrospective cohort study comparing patients undergoing ECX and FLOT neoadjuvant chemotherapy between 2014 and 2021. Pathological outcomes were examined including, Mandard tumour regression grade (1-5), complete nodal response (cN+ to ypN0), clinically node negative nodal progression (cN0 to ypN+). Results 226 patients had data available for analysis (193 ECX and 33 FLOT). 27% (52/193) of patients receiving ECX showed a response in the primary tumour (Mandard 1,2,3) compared to 63% (21/33) with patients undergoing FLOT (p < 0.001). Complete nodal response rates were 25% in ECX patients and 21% FLOT patients (p = 0.556). Clinically node negative nodal upstaging (cN0 to pN+) was higher among FLOT patients 30% (13/33) than ECX patients 12% (24/193) (p < 0.001). Conclusions FLOT chemotherapy confers improved primary tumour response. However, these findings were not echoed in locoregional nodal responses. Survival advantages with FLOT may result from improved responses in primary tumour and not improved systemic coverage. More data will be needed to explore this and over-come the confounding effect of staging inaccuracies. However, understanding systemic and loco-regional responses of different chemotherapy regimens will be needed to tailor future neoadjuvant treatment regimens.

500 Consecutive Robotic Lobectomies for Non-Small Cell Lung Cancer: Perioperative and Oncologic Outcomes

Objective Clinical adoption of robotic lobectomy for management of lung cancer is rapidly increasing across the world. Several studies have evaluated the technique with regards to perioperative and cost outcomes, with evidence beginning to grow regarding long-term oncologic outcomes. We report perioperative and oncologic outcomes in our single institution experience with 500 consecutive robotic lobectomies, including a significant portion for locally advanced disease. Methods This study is a retrospective review of the first 500 robotic lobectomies performed at our institution from 2010 to 2018. Segmentectomy, pneumonectomy, and lobectomy for other conditions were excluded. Descriptive statistics and Kaplan-Meier survival analysis are presented. Results Pathologic stage distribution was IA in 194 (39%), IB in 54 (11%), IIA in 41 (8%), IIB in 109 (22%), IIIA in 83 (17%), IIIB in 11 (2%), and IV in 8 (2%). Elective conversion occurred in 26 cases (5.2%) and emergent conversion occurred in 3 cases (0.6%). Mean length of stay was 3.7 days (1 to 40). The most common complications encountered were atrial fibrillation in 71 (14.2%) and prolonged air leak in 49 (9.8%). Thirty-day mortality occurred in 3 patients (0.6%). Nodal upstaging was 16.6%. Stage specific overall survival outcomes included an 84% survival for stage IA patients, 73% for IB, 68% for IIA, 63% for IIB, and 49% for IIIA disease. Conclusions Robotic lobectomy for lung cancer is a feasible technique for treatment of non-small cell lung cancer with low perioperative morbidity and mortality. Furthermore, excellent oncologic outcomes can be achieved with this approach.

Nodal Upstaging Evaluation After Robotic-Assisted Lobectomy for Early-Stage Non-small Cell Lung Cancer Compared to Video-Assisted Thoracic Surgery and Thoracotomy: A Retrospective Single Center Analysis

Introduction: The standard surgical procedures for patients with early-stage NSCLC is lobectomy-associated radical lymphadenectomy performed by using the thoracotomy approach. In the last few years, minimally invasive techniques have increasingly strengthened their role in lung cancer treatment, especially in the early stage of the disease. Although the lobectomy technique has been accepted, controversy still surrounds lymph node dissection. In our study, we analyze the rate of upstaging early non-small cell lung cancer patients who underwent radical surgical treatment using the robotic and the VATS techniques compared to the standard thoracotomy approach.Methods and Materials: We retrospectively reviewed patients who underwent a lobectomy and radical lymphadenectomy at our Institute between 2010 and 2019. We selected 505 patients who met the inclusion criteria of the study: 237 patients underwent robotic surgery, 158 patients had thoracotomy, and 110 patients were treated with VATS. We analyzed the demographic features between the groups as well as the nodal upstaging rate after pathological examination, the number of dissected lymph nodes and the ratio of dissected lymph nodes to metastatic lymph nodes of the three groups.Results: The patients of the three groups were homogenous with respect to age, sex, and histology. The postoperative major morbidity rate was significantly higher in the thoracotomy group, and hospital stay was significantly longer. The percentage of the mediastinal nodal upstaging rate and the number of dissected lymph nodes was significantly higher in the robotic group compared with the VATS group. The ratio of dissected lymph nodes to metastatic lymph nodes was significantly lower compared with the VATS group and the thoracotomy group.Discussion: The prognostic impact of the R(un) status is still highly debated. A surgical approach that allows better results in terms of resection has still not been defined. Our results show that robotic surgery is a safe and feasible approach especially regarding the accuracy of mediastinal lymphadenectomy. These findings can lead to defining a more precise pathological stage of the disease and, if necessary, to more accurate postoperative treatment.

Impact of the Extent of Lymph Node Dissection on Precise Staging and Survival in Clinical I–II Pure-Solid Lung Cancer Undergoing Lobectomy

Background: This study sought to determine the optimal number of examined lymph nodes (ELNs) and examined node stations (ENSs) in patients with radiologically pure-solid non–small cell lung cancer (NSCLC) who underwent lobectomy and ipsilateral lymphadenectomy by investigating the impact of ELNs and ENSs on accurate staging and long-term survival. Materials and Methods: Data from 6 institutions in China on resected clinical stage I–II (cI–II) NSCLCs presenting as pure-solid tumors were analyzed for the impact of ELNs and ENSs on nodal upstaging, stage migration, recurrence-free survival (RFS), and overall survival (OS). Correlations between different endpoints and ELNs or ENSs were fitted with a LOWESS smoother, and the structural break points were determined by Chow test. Results: Both ELNs and ENSs were identified as independent prognostic factors for OS (ENS hazard ratio [HR], 0.690; 95% CI, 0.597–0.797; P<.001; ELN HR, 0.950; 95% CI, 0.917–0.983; P=.004) and RFS (ENS HR, 0.859; 95% CI, 0.793–0.931; P<.001; ELN HR, 0.960; 95% CI, 0.942–0.962; P<.001), which were also associated with postoperative nodal upstaging (ENS odds ratio [OR], 1.057; 95% CI, 1.002–1.187; P=.004; ELN OR, 1.186; 95% CI, 1.148–1.226; P<.001). A greater number of ELNs and ENSs correlated with a higher accuracy of nodal staging and a lower probability of stage migration. Cut-point analysis revealed an optimal cutoff of 18 LNs and 6 node stations for stage cI–II pure-solid NSCLCs, which were validated in our multi-institutional cohort. Conclusions: Extensive examination of LNs and node stations seemed crucial to predicting accurate staging and survival outcomes. A threshold of 18 LNs and 6 node stations might be considered for evaluating the quality of LN examination in patients with stage cI–II radiologically pure-solid NSCLCs.