Lung Cancer Diagnosis Procedure, Test
Endobronchial Ultrasound (EBUS) - A New Lung Cancer Diagnosis Technique
UW Paul P. Carbone Comprehensive Cancer Center
Lung Cancer
Endobronchial Ultrasound (EBUS)MADISON - Maggie Sullivan quit smoking decades ago, so the Verona woman was shocked to learn her nagging cough was actually lung cancer.
It was a life-changing diagnosis, but thanks to a new diagnostic innovation used by UW Health lung surgeon Tracey Weigel, MD, she was able to avoid unnecessary surgery.
Sullivan underwent an Endobronchial Ultrasound, or EBUS, an emerging technique which offers a more precise way of assessing a patient's lymph nodes and determining if lung cancer has spread to other parts of the body. UW Hospital is one of only two hospitals in Wisconsin to use the technology.
A PET scan (positron emission tomography) suggested Sullivan's lung cancer was localized, but already at stage three – in the lymph nodes near the windpipe (trachea).
But just before surgery to remove a tumor from Sullivan's right lung, Weigel, a member of the University of Wisconsin Paul P. Carbone Comprehensive Cancer Center, performed an endobronchial ultrasound. To perform the procedure, Weigel inserted a bronchoscope with a special ultrasound transmitter and processor at its tip into Sullivan's windpipe. Using the probe's detailed images, Weigel was able to assess whether the cancer had spread into the windpipe or to the lymph nodes on either side.
The EBUS found Sullivan's lung cancer was just stage one – not the more advanced stage three as was initially thought – and Sullivan's cancer was not present in any lymph nodes on either side of the trachea. That meant Sullivan was able to have surgery that did not damage nerve and muscle tissue.
"This is really changing how we practice," says Weigel. "It's just better care. There can be just so many uncertainties, and you don’t want to put people through a big operation if it will not help them."
"EBUS is really going to help us better know what we're dealing with and hopefully make better choices for the patient," Weigel added. "The incidence of us having to go to 'Plan B' will be less and less."
Sullivan, an assistant dean at the UW-Madison College of Letters and Science, spent just two days in the hospital and needed only over-the-counter pain medicine a week after the procedure.
Less Invasive, Shorter Hospital Stay
With lung and esophageal cancers, treatment decisions and the patient's prognosis is directly related to the extent of the disease, or the "stage" of the cancer. Malignancies in the chest can easily spread through the body via lymph nodes. If tumors have invaded a patient's lymph nodes, this can dramatically change the initial "staging" of the cancer, as well as the options for initial treatment.
Lung cancer is typically diagnosed after it has already spread, and long-term prognosis for patients is usually poor. But with the innovation of endobronchial ultrasound and its ability to accurately show the cancer stage, patients with early-stage lung cancer may avoid more extensive surgery. With less-invasive procedures, such patients may then leave the hospital sooner and use less pain medication as they recover.
"The type of treatment we recommend for lung cancer patients depends to a large degree on the stage of their cancer," says Weigel. "The great advantage of this technology is that people who will benefit from surgery will not be denied surgery or receive unnecessary chemotherapy because of less accurate conventional staging with CT and PET scans."
Weigel says it also means people with advanced lung cancer will not need to undergo unnecessary surgery that may not help them. She and her colleague, James Maloney, MD, have performed more than 40 endobronchial ultrasound procedures at UW Hospital.
The EBUS Procedure
The EBUS technology is a hybrid employing ultrasound guidance with a bronchoscope, enabling real-time transbronchial needle aspiration to be performed. This combination aids in the diagnosis and staging of lung cancer. In clinical trials, many patients evaluated with EBUS were able to forego more invasive procedures, such as mediastinoscopy, thoracoscopy or thoracotomy.
Using EBUS, biopsies are performed through the trachea using ultrasound rather than surgical incisions that must be made in other, more invasive procedures. The EBUS procedure is usually completed in less than half an hour.
In an endobronchial ultrasound, patients are placed under conscious sedation or general anesthesia and a small scope is passed through the mouth down into the windpipe. The scope has a small instrument at its tip called a transducer, which can be pointed in different directions to produce images of lymph nodes and other structures in the area between the lungs, called the mediastinum.
"It allows you to look in areas that have traditionally been hard to biopsy," explains Weigel.
If suspicious areas are seen–such as enlarged lymph nodes–a hollow needle can be passed through the bronchoscope and guided by real-time ultrasound into the abnormal structures to obtain a biopsy.
"It's really a well-designed system," Weigel says of endobronchial ultrasound technology. "In many cases, it offers better sensitivity and specificity without having to make an incision."
Date published: 03/05/2008
Votes:31