Less-Invasive Method Finds Stage of Lung Cancer
Nov. 23, 2010 — A less-invasive method to determine the stage of non-small-cell lung cancer is effective, often sparing the patient the need for general anesthesia and a surgical procedure, according to a new study.
Under currently accepted guidelines, staging of non-small-cell lung cancer is done either by a special ultrasound technique of the internal organs called endosonography or a surgical diagnostic procedure called a mediastinoscopy, in which doctors look at the inside of the upper chest between and in front of the lungs.
If the ultrasound detects no cancer, doctors move on to the surgical staging technique to be sure; if the ultrasound detects cancer, the doctor can then move on to a treatment plan.
In the new study, Jouke Annema, MD, PhD, a chest physician at the Leiden University Medical Center in Leiden, Netherlands, compared surgical staging alone vs. ultrasound followed by staging if necessary.
”These data clearly indicate you should start with the endosonography,” he tells WebMD.
The study is published in The Journal of the American Medical Association.
Lung cancer, now the most commonly diagnosed cancer worldwide, with 1.35 million cases yearly, is also the most frequent cause of cancer death, claiming 1.18 million lives a year, Annema writes.
While most patients have advanced-stage disease when it is first detected, for others a search for the cancer spread or metastasis is essential before deciding on treatment.
One challenge is detecting cancers in the small lymph nodes nearby.
Comparing Staging Techniques
Annema and his team evaluated 241 lung cancer patients, assigning 118 to surgical staging and 123 to ultrasound. Sixty-five patients in the ultrasound group also had surgical staging because the ultrasound was negative (thus requiring another detection method to be sure).
Cancer spread to the nodes was found in 41 patients (35%) by surgical staging but in 56 patients (46%) by ultrasound and in 62 patients (50%) by ultrasound plus surgical staging.
“If you first do ultrasound then staging, the sensitivity is 94%,” Annema tells WebMD. Sensitivity refers to the probability that a person having the disease will be identified correctly. “You only do the surgical staging if the ultrasound is completely normal. If you do ultrasound and find lymph node involvement, then you know the disease has spread.”
The new strategy, he says, also reduces the number of unnecessary incisions into the chest wall (thoracotomies). The number of unnecessary thoracotomies was 21 (18%) of the surgical staging group compared to nine (7%) of the ultrasound-first group.
Complication rates were similar. Most common, the researchers found, was persistent hoarseness.
“‘The conclusion is, if you stage patients according to the new strategy and do endosonography first, then surgical staging, you significantly detect more spread of the disease,” he says, while reducing the number of unnecessary chest incisions.