Complete mediastinal lymphadenectomy: the core component of the multidisciplinary therapy in resectable non-small cell lung cancer

Abstract

There is a great deal of concern about metastasis of lung cancer to regional lymph nodes, due partly to the work of groups of thoracic surgeons in Japan and North America beginning in the 1970s. The classification of regional lymph node stations for lung cancer staging published by Mountain and Dresler has been widely adopted for more than ten years. Anatomic landmarks for 14 levels of intrapulmonary, hilar, and mediastinal lymph nodes stations are designated. Skip transfer and occult lymph node metastasis, confirmed by studies regarding the mode of spread of intrathoracic lymphatic metastasis, are two theoretical bases for complete mediastinal lymphadenectomy of lung cancer. However, whether or not the degree of the dissection influences prognosis, the role of systematic nodal dissection (SND) vs mediastinal lymph node sampling (MLD) in resectable non-small cell lung cancer (NSCLC) remains controversial. A systematic literature search was performed to identify relevant reports, making full use of the 'Cited by,' 'Related Records,' 'References,' and 'Author Index' functions in the PubMed and ISI Web of Science databases. This paper presents a review of the role of mediastinal lymph node distribution and methods of determining suitability for hilar and mediastinal lymphadenectomy based on the four subsets of stage IIIA-N2, balancing the cost vs effect of mediastinal lymph node dissection in resectable NSCLC, focusing on the stage migration bias in clinical trials comparing SND and MLS, recommending a reasonable node dissection sequence, improving the prospects for the perioperative anti-tumor therapy based on mediastinal lymphadenectomy, and evaluating the various preoperative staging techniques. Finally, we believe that, besides the role of complete resection and accurate staging, the complete mediastinal lymphadenectomy is the core component of the lung cancer multidisciplinary therapy, and suggest that the values of lymphadenectomy should be further assessed using decision-tree analysis based on large-scale prospective randomized trials and pooled analysis to evaluate the costs vs effects.

Lymph Node Assessment and Impact on Survival in Video-Assisted Thoracoscopic Lobectomy or Segmentectomy

“…As this trial greatly influenced surgeon assessment of mediastinal lymph 11 to 15 nodes conferred the lowest hazard ratio for death. Other authors recommend examination of a minimum of 10 lymph nodes and at least 3 lymph node stations [23,24]. The RNs greater than 10 in our patient cohort was predictive of nodal upstaging, but was not predictive of survival.…”

Number of Lymph Nodes Harvested From a Mediastinal Lymphadenectomy

“…However, others recommend examination of a minimum of 10 lymph nodes and at least three lymph node stations. 8,9 These harvested from at least three stations in 521 patients (99.4%). Combining these data, 516 (98.5%) had at least six lymph nodes examined from three lymph node stations and 469 (89.5%) had at least 10 lymph nodes examined from three stations.…”

“…16 nodes did not confer any further improvement in survival. 8,9 In a population-based study of 16,800 patients, multivariate analysis showed maximum survival for allcause mortality (hazard ratio, 0.78; 95% CI, 0.68-0.90) and lung-cancer-specific mortality (hazard ratio, 0.74; 95% CI, 0.62-0.89) in patients who had resection of 13 to 16 lymph nodes. 15 Similar results were reported by Ou and Zell 16 and Varlotto et al 17 Mature results of the ACOSOG Z0030 trial will provide level 1 evidence addressing the question of survival benefi t. 1 IIIA T2 N2 Squamous LUL 5 2 IIIA T2 N2 Adenocarcinoma LLL 9 3 IIIA T2 N2 Adenocarcinoma LUL 5, 11L 4 IIIA T2 N2 Squamous LUL 7 5 IIIA T2 N2 Bronchoalveolar LLL 7, 12L 6 IIIA T2 N2 Other NSCLC a LUL, LLL 11L b 7 IIIA T1 N2 Adenocarcinoma LUL 6, 12L 8 IIIA T1 N2 Adenocarcinoma LLL 6, 7, 11L 9 IIIA T1 N2 Other NSCLC a LUL 5, 12L 10 IIIA T2 N2 Adenocarcinoma RLL 7, 11R 11 IIIB T4 N2 Adenocarcinoma RUL 2R, 4R 12 IIIA T3 N2 Adenocarcinoma RLL 4R 13 IIIA T2 …”

“…Dr Inculet: contributed to acquisition and review of data and approval of the manuscript. study group recommends that the number of lymph nodes resected during MLND be Ն 12, with nodes removed from stations 2R, 4R, 7, 8, 9, and 10R on the right, and stations 4L, 5,6,7,8,9, and 10L on the left.…”

Pneumonektomie

“…Die systematische Lymphknotendissektion führt zu einem besseren Gesamtüberleben bei verlängertem krankheitsfreiem Intervall. Dabei ist die Morbidität und Mortalität bei der systematischen Lymphknotendissektion im Vergleich zum Lymphknoten-Sampling nicht erhöht [19]. Nur durch eine systematische Lymphknotendissektion ist es möglich, eine wirkliche komplette Resektion (R0) zu erreichen.…”