For patients with suspected non–small-cell lung cancer, adding endosonography before surgical staging improves detection of mediastinal nodal metastases, thus reducing unnecessary thoracotomies by more than half, according to a report in the Nov. 24th issue of JAMA.
In addition, because endosonography is minimally invasive, adding this step doesn’t raise the rate of complications for staging procedures, said Dr. Jouke T. Annema of Leiden (the Netherlands) University Medical Center and associates.
The researchers compared surgical staging alone to endosonography followed by surgical staging because "at present it is not known whether initial mediastinal tissue staging of lung cancer by endosonography improves the detection of nodal metastases." Failure to detect such metastases during staging results in patients undergoing thoracotomy for tumor resection, only to have the thoracotomy aborted when unresectable or metastatic lung disease is discovered.
The investigators randomized 241 patients suspected of having resectable NSCLC, who were treated at four tertiary referral centers in Belgium, the Netherlands, and the United Kingdom. Patients were assigned to surgical staging alone, which is the current standard of care (118 subjects), or to endosonography followed by surgical staging (123 subjects).
The sensitivity of surgical staging alone was 79%. This improved to 94% when endosonography was combined with surgical staging, Dr. Annema and colleagues said (JAMA 2010;304:2245-52).
Mediastinal nodal metastases were found in 41 of 118 patients (35%) by surgical staging alone, compared with 62 of 123 patients (50%) by the combined approach. This means that there were 21 unnecessary thoracotomies with surgical staging alone, for a rate of 18%, compared with 9 with the combined approach, for a rate of 7%.
The complication rate was 6% for surgical staging, compared with 1% for endosonography.
These findings show that endosonography improves the sensitivity of surgical staging, halves the rate of unnecessary thoracotomy, and has a low complication rate. Because it also does not require general anesthesia and has been shown in previous studies to be cost effective as well as preferred by patients, "endosonography should be the first step for mediastinal nodal staging," the investigators said.
They added that all of the staging procedures in this study were performed in specialty centers by highly trained and experienced interventionists, so the applicability of the study findings to other settings is limited.
The study was supported in part by Hitachi Medical Systems, COOK, Olympus, the Zorgprogramma Oncologie Gent, the U.K. National Health Service R & D Health Technology Assessment Program, and the National Institute for Health Research Cambridge Biomedical Research Centre.