No one doubts about the need of doing mediastinal lymph node sampling during lobectomy for lung cancer. In the presence of a patient deemed cN0, it is well known that sampling, or better yet, dissecting mediastinal lymph nodes will result in a significant number (up to 20%) of patients that will be upstaged to N1 or N2 after the lung resection.
N1 and N2 patients are better off treated with postoperative chemotherapy to improve survival. If you don’t look hard enough for the lymph node stations, you will downstage patients with nodal disease, and this means a patient getting suboptimal lung cancer treatment.
That’s why we put so much emphasis on at least sampling every lymph node station at the time of the lung resection.
So the question is: what lymph node stations do I look for in right-side lung resection? If the patient has a biopsy proven lung cancer I start doing the lymph node dissection. The first station I get is station #9R when I take down the inferior pulmonary ligament. At the same time I look for para-esophageal lymph nodes, say station #8R. Then, I keep opening the posterior mediastinal pleura and get all the #7s. Doing a #7 lymph node dissection involves to dissect from the inferior border of the right bronchus all the way to the left bronchus, and anteriorly to the posterior aspect of the pericardium. There is always a substantial amount of lymph nodes in this position. Then, I focus in #4R and #2Rs. I open the mediastinal pleura above and below the azigos vein. I don’t ligate this vein, but instead dissect below it and up above it to get all the adipose and lymphatic tissue in the right para-tracheal area. Care should be taken not to damage the left recurrent nerve when dissecting behind the airway. I submit all these tissue labelled as #2R and 4Rs. The superior limit of this dissection is the right subclavian artery, but I never go that far up as a lesion of this vessel it’s a hard one to repair from a thoracotomy.
In this way I cleared up all the mediastinal lymph nodes and proceed to the lung resection. N1 nodes are usually taken out with the lung specimen, but I try to separate #10Rs and #11Rs if possible. If the patient hasn’t a biopsy proven lung cancer, I usually start by getting the diagnosis and if frozen section shows cancer, do the lymph node dissection thereafter.
I consider this to be the best way to rule out lymph node spread from the lung. Getting all these lymph node stations gives you more certainty that you are not missing a patient with lymph node disease and best of all that you are not down-staging any patient.
What lymph node stations do you usually sample or dissect during a right-side lung resection?
Sebastian