Robotic-assisted thoracoscopic surgery for clinically stage IIIA (c-N2) NSCLC—is it justified?

Robotic-assisted thoracoscopic surgery for clinically stage IIIA (c-N2) NSCLC—is it justified?

Walter Weder1, Katarzyna Furrer2, Isabelle Opitz2

1Thoracic Surgery, Klinik Bethanien, Zürich, Switzerland; 2Department of Thoracic Surgery, University Hospital Zurich, Zürich, Switzerland

Correspondence to: Walter Weder. Thoracic and General Surgery Privatklinik Bethanien, Toblerstrasse 51, 8044 Zürich, Switzerland. Email:

Comment on: Huang J, Li C, Li H, et al. Robot-assisted thoracoscopic surgery versus thoracotomy for c-N2 stage NSCLC: short-term outcomes of a randomized trial. Transl Lung Cancer Res 2019;8:951-8.

Submitted May 10, 2020. Accepted for publication Jun 27, 2020.

doi: 10.21037/tlcr-20-647

Work-up as well as management of patients with non-small cell lung cancer (NSCLC) and clinically suspicious mediastinal lymph nodes (c-N2) should consider current guidelines (1), although the final implementation differs between several institutions and countries.

The authors have selected upfront surgery without prior invasive or non-invasive mediastinal staging and assessed the short-term outcome of robotic assisted surgery (RATS) in comparison to thoracotomy in a multicenter randomized controlled trial (2). No meaningful differences were found in most of the parameters, besides significant differences in intraoperative blood loss, drainage time, and postoperative pain (2).

The question, whether these short-term outcome parameters are relevant for the evaluation of treatment quality and efficacy of patients with locally advanced lung cancer, may lead to a controversial discussion, particularly in relation to the more relevant long-term outcome results. Patients and doctors most likely agree that overall- (OS) and disease-free survival (DFS) in a lung cancer operation is most important and side effects from surgery such as drainage and hospitalisation time are clearly less meaningful. OS and DFS after surgery for clinical stage III (N2) depends on two main factors, such as complete resection of the tumor, a so called R0-resection and definitive pathological mediastinal lymph node stage. The latter guides the need for adjuvant therapy including adjuvant chemotherapy, targeted treatment, immunotherapy, and radiotherapy. OS and DFS were not assessed in the reported trial but R0 and R1 resection were equal in both groups indicating that radicality of surgery was comparable in both groups, and independent from the approach. This was found already in multiple studies before, which compared video-assisted thoracoscopic surgery (VATS) with thoracotomy in early stage lung cancer up to a tumor size of less than 3 cm (3,4). Furthermore, these studies showed that survival after resection was comparable for both approaches (5-10). In some studies, comprehensive reviews and meta-analyses, VATS was even comparing favorably to thoracotomy with survival advantage for VATS procedure.

Two published comparisons of long-term oncologic outcomes of robotic lobectomy for early-stage NSCLC versus VATS and open thoracotomy approach show that RATS lobectomy was associated with durable freedom of recurrence and long-term survival equivalent to those achieved with VATS and the traditional open thoracotomy approach. As presented by the Italian group of Veronesi et al., RATS approach for locally advanced NSCLC with clinically evident or occult N2 is safe and feasible with 3- and 5-year OS at 61.2% and 49% respectively (11).

In term of radical R0-resection of early stage lung cancer with RATS compared with VATS, there were also no quality issues in the literature and comparison between minimally invasive (RATS and VATS) versus open lobectomy of locally advanced NSCLC achieved a similar R0 resection rate between the groups (12).

The second key issue of an oncologically correct lung cancer operation is the extent of hilar and mediastinal lymph node clearance. The number of lymph nodes and the number of lymph node stations resected represents figures of lymph adenectomy completeness. The pathological result may lead to recommendations for or against adjuvant therapy. In addition, in this regard, both study arms showed the same number of investigated lymph nodes. Since all patients had upfront surgery without induction chemo- or chemoradiation and the lymph node removal extent was limited to resectable ones in this trial, the result is not a surprise. It has been shown also in many series comparing VATS with thoracotomies (4,8,13-16) that lymph node resection can be done in at least equal quality using the minimal invasive approach. RATS compared to VATS came to similar results (17-19). Furthermore, Merritt and colleagues show, that mean numbers of total lymph nodes and N2 lymph nodes were significantly higher in the robotic lobectomy group (P<0.0001) (20).

Many centers would assess enlarged mediastinal lymph nodes by EBUS or mediastinoscopy and in case of histologically proven mediastinal disease would initiate neoadjuvant chemo- or chemoradiation prior to resection. Surgery thereafter is occasionally more difficult because the dissection planes may be fused and lymph nodes may become adherent to vessels (such as v. cava, pulmonary vessels) or the trachea. It would be interesting to compare the open technique with RATS after neo-adjuvant therapy when downstaging occurred and the dissecting planes fibrous and lymph nodes stick to vessels, airways, and esophagus. The procedure is then more of a challenge and patients undergoing RATS lobectomy after induction chemotherapy with or without radiation therapy may be at greater risk for recurrent laryngeal nerve injury, tracheal/bronchial injury, and pulmonary embolism (21). Furthermore, as presented by Veronesi and colleagues, on robotic resection of stage III lung cancer patients after induction chemotherapy, required in 15% conversion and 12% patients developed grade III or IV postoperative complications (11).

Intraoperative blood loss was significantly different when comparing the two surgical approaches. The question comes up, if a difference of 80 mL is clinically meaningful or not. Blood loss has a negative influence on OS after lung cancer operations (22). However, only when the amount of blood loss is larger than 80 mL a relevant impact on the immune system may occur. On the other hand, a blood loss of only 80 mL in the RATS group may be an indicator, that RATS allows very precise and most atraumatic surgery, which is often stated by RATS surgeons. The reason includes facts such as the excellent 3D view, instruments which allow a precise dissecting technique, and possible also the fact, that a surgeon needs to avoid even the smallest bleeding in order to have a good view and control of the operation.

Drainage time and the amount of drainage fluid differed statistically between the groups but with a relatively minor clinical meaning. The same can be said for pain management. Early postoperative pain was clearly less in RATS treated patients, which is an advantage. But, the pain in the thoracotomy group seems to be manageable looking at the difference in the visual analog scale.

What can we finally conclude from this randomized trial comparing RATS with thoracotomy in c-N2 NSCLC. RATS allows a safe and radical procedure also in locally advanced lung cancer, at least when upfront surgery without neoadjuvant treatment is used. The latter needs to be further evaluated. Since safety and radicality are the key elements of all cancer operations, the most important goal is achieved. Secondary factors such as early postoperative pain, drainage time, and intraoperative blood loss favor the minimal-invasive approach by RATS—as previously shown for VATS. As a word of caution, safety and quality of surgery depends heavily on the surgeon’s experience and technique and this trial was performed in hospitals with high case volumes und experienced surgeons. They have to be congratulated on their excellent results.


Funding: None.


Provenance and Peer Review: This article was commissioned by the editorial office, Translational Lung Cancer Research. The article did not undergo external peer review.

Conflicts of Interests: All authors have completed the ICMJE uniform disclosure form (available at WW—Astra Zeneca: Advisory Board & Speaker; Covidien (Medtronic): Teaching Grant & Speaker. The other authors have no conflicts of interest to declare.

Ethical statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See:


  1. Postmus PE, Kerr KM, Oudkerk M, et al. Early and locally advanced non-small-cell lung cancer (NSCLC): ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol 2017;28 Suppl 4:iv1-21. [Crossref] [PubMed]
  2. Huang J, Li C, Li H, et al. Robot-assisted thoracoscopic surgery versus thoracotomy for c-N2 stage NSCLC: short-term outcomes of a randomized trial. Transl Lung Cancer Res 2019;8:951-8. [Crossref] [PubMed]
  3. Whitson BA, Groth SS, Duval SJ, et al. Surgery for early-stage non-small cell lung cancer: a systematic review of the video-assisted thoracoscopic surgery versus thoracotomy approaches to lobectomy. Ann Thorac Surg 2008;86:2008-16; discussion 2016-8. [Crossref] [PubMed]
  4. Swanson SJ, Herndon JE 2nd, D'Amico TA, et al. Video-assisted thoracic surgery lobectomy: report of CALGB 39802--a prospective, multi-institution feasibility study. J Clin Oncol 2007;25:4993-7. [Crossref] [PubMed]
  5. Sugi K, Kaneda Y, Esato K. Video-assisted thoracoscopic lobectomy achieves a satisfactory long-term prognosis in patients with clinical stage IA lung cancer. World J Surg 2000;24:27-30; discussion 30-1. [Crossref] [PubMed]
  6. Paul S, Isaacs AJ, Treasure T, et al. Long term survival with thoracoscopic versus open lobectomy: propensity matched comparative analysis using SEER-Medicare database. Bmj 2014;349:g5575. [Crossref] [PubMed]
  7. Ezer N, Kale M, Sigel K, et al. Outcomes after Video-assisted Thoracoscopic Lobectomy versus Open Lobectomy for Early-Stage Lung Cancer in Older Adults. Ann Am Thorac Soc 2018;15:76-82. [Crossref] [PubMed]
  8. Yang CJ, Kumar A, Klapper JA, et al. A National Analysis of Long-term Survival Following Thoracoscopic Versus Open Lobectomy for Stage I Non-small-cell Lung Cancer. Ann Surg 2019;269:163-71. [Crossref] [PubMed]
  9. Su S, Scott WJ, Allen MS, et al. Patterns of survival and recurrence after surgical treatment of early stage non-small cell lung carcinoma in the ACOSOG Z0030 (ALLIANCE) trial. J Thorac Cardiovasc Surg 2014;147:747-52; discussion 752-3. [Crossref] [PubMed]
  10. Flores RM, Park BJ, Dycoco J, et al. Lobectomy by video-assisted thoracic surgery (VATS) versus thoracotomy for lung cancer. J Thorac Cardiovasc Surg 2009;138:11-8. [Crossref] [PubMed]
  11. Veronesi G, Park B, Cerfolio R, et al. Robotic resection of Stage III lung cancer: an international retrospective study. Eur J Cardiothorac Surg 2018;54:912-9. [Crossref] [PubMed]
  12. Park BJ, Yang HX, Woo KM, et al. Minimally invasive (robotic assisted thoracic surgery and video-assisted thoracic surgery) lobectomy for the treatment of locally advanced non-small cell lung cancer. J Thorac Dis 2016;8:S406-13. [Crossref] [PubMed]
  13. Palade E, Passlick B, Osei-Agyemang T, et al. Video-assisted vs open mediastinal lymphadenectomy for Stage I non-small-cell lung cancer: results of a prospective randomized trial. Eur J Cardiothorac Surg 2013;44:244-9; discussion 249. [Crossref] [PubMed]
  14. Mei J, Guo C, Xia L, et al. Long-term survival outcomes of video-assisted thoracic surgery lobectomy for stage I-II non-small cell lung cancer are more favorable than thoracotomy: a propensity score-matched analysis from a high-volume center in China. Transl Lung Cancer Res 2019;8:155-66. [Crossref] [PubMed]
  15. Boffa DJ, Kosinski AS, Paul S, et al. Lymph node evaluation by open or video-assisted approaches in 11,500 anatomic lung cancer resections. Ann Thorac Surg 2012;94:347-53; discussion 353. [Crossref] [PubMed]
  16. Yang HX, Woo KM, Sima CS, et al. Long-term Survival Based on the Surgical Approach to Lobectomy For Clinical Stage I Nonsmall Cell Lung Cancer: Comparison of Robotic, Video-assisted Thoracic Surgery, and Thoracotomy Lobectomy. Ann Surg 2017;265:431-7. [Crossref] [PubMed]
  17. Guo F, Ma D, Li S. Compare the prognosis of Da Vinci robot-assisted thoracic surgery (RATS) with video-assisted thoracic surgery (VATS) for non-small cell lung cancer: A Meta-analysis. Medicine (Baltimore) 2019;98:e17089. [Crossref] [PubMed]
  18. Wei S, Chen M, Chen N, et al. Feasibility and safety of robot-assisted thoracic surgery for lung lobectomy in patients with non-small cell lung cancer: a systematic review and meta-analysis. World J Surg Oncol 2017;15:98. [Crossref] [PubMed]
  19. Hu X, Wang M. Efficacy and Safety of Robot-assisted Thoracic Surgery (RATS) Compare with Video-assisted Thoracoscopic Surgery (VATS) for Lung Lobectomy in Patients with Non-small Cell Lung Cancer. Comb Chem High Throughput Screen 2019;22:169-78. [Crossref] [PubMed]
  20. Merritt RE, Kneuertz PJ, D'Souza DM. Successful Transition to Robotic-Assisted Lobectomy With Previous Proficiency in Thoracoscopic Lobectomy. Innovations (Phila) 2019;14:263-71. [Crossref] [PubMed]
  21. Glover J, Velez-Cubian FO, Toosi K, et al. Perioperative outcomes and lymph node assessment after induction therapy in patients with clinical N1 or N2 non-small cell lung cancer. J Thorac Dis 2016;8:2165-74. [Crossref] [PubMed]
  22. Nakamura H, Saji H, Kurimoto N, et al. Impact of intraoperative blood loss on long-term survival after lung cancer resection. Ann Thorac Cardiovasc Surg 2015;21:18-23. [Crossref] [PubMed]
Cite this article as: Weder W, Furrer K, Opitz I. Robotic-assisted thoracoscopic surgery for clinically stage IIIA (c-N2) NSCLC—is it justified? Transl Lung Cancer Res 2021;10(1):1-4. doi: 10.21037/tlcr-20-647