Accurate mediastinal lymph node staging is mandatory before deciding to perform a resection in otherwise operable patients with non-small cell lung cancer (NSCLC). In a retrospective study of all hospitals in the southwestern part of the Netherlands it was shown that biopsies by mediastinoscopy were positive in 21%, these patients did not undergo unnecessary thoracotomy. However, the prevalence of positive N2 nodes in patients undergoing thoracotomy was still 13%. The sensitivity of mediastinoscopy was 50% if the CT scanning was negative and 75% if CT scanning showed lymphnodes larger then 1 cm in diameter. These results show suboptimal staging performance in our region, reason for staging guidelines and instruction.
In the IKR region we therefor started from 1999 onwards to standardise the staging procedures in NSCLC. In every patient with a NSCLC except a patient with proven peripheral squamous carcinoma T1 a mediastinoscopy is performed with sampling of lymphnodes according to Naruke stations 2 left and right, station 4 left and right and 7. Furthermore, a left lateral mediastinotomy is done in those patients with enlarged node 5,6 with a left-sided upper lobe tumour. All mediastinoscopies are registered.
To increase performance a videomediastinoscopy (VM) is importance for a number of reasons. With the VM the enhanced view on a monitor gives good anatomical information. With VM the surgeon can differentiate between structures as the pulmonary vein, anthracotic lymphnodes arteries etc. Careful dissection is possible even with removal of a complete lymphnode with secure haemostasis. We performed in our institution in 1999 31 mediastinoscopies. It was possible to perform a complete mediastinoscopy in 27 patients. We had one bleeding of the pulmonary vein, and one damaged recurrent nerve.
The VM is a valuable tool for lymphnode sampling for staging of patients with NSLC. Furthermore it is safe and offers the possibility to increase accuracy and thus quality.