Study shows open biopsy more accurately diagnoses mesothelioma subtypes
A type of biopsy called open thoracotomy may be the most accurate way to diagnose the specific type of pleural mesothelioma.
A team of Australian researchers found that biopsy by thoracotomy achieved accurate diagnoses in 83 percent of cases, compared with two other common techniques, thoracoscopy and computed tomography (CAT Scan).
There are three major subtypes of pleural mesothelioma, depending on the classification of the cells. Epithelial is the most common subtype of the disease; sarcomatoid is the rarest. In “biphasic” mesothelioma patients, both epithelioid and sarcomatoid cells are present.
Determining the subtype of meothelioma is important. While there is no cure for the disease, chances for survival are higher in patients with epithelial tumors, which respond better to surgery than biphasic or sarcomatoid mesothelioma.
While thoracotomy is more invasive than the other methods and carries a greater risk of complications, it allows surgeons to collect a larger sample of malignant cells for diagnostic purposes.
In the current study, to be published in the March 201 issue of the Journal of Thoracic Oncology, researchers examined the medical charts and electronic records of 83 pleural mesothelioma patients who underwent extrapleural pneumonectomy, a complex surgery to remove the lung and parietal pleura, the membrane that surrounds the lung.
In 81 percent of the cases, thoracoscopy, a minimally invasive procedure that uses a special type of endoscope for visualization, was used to diagnose the disease; 11 percent of the patients were diagnosed via CAT Scan, while 7 percent underwent open thoracotomy.
To determine the accuracy of the diagnostic method, pathologists compared the initial subtype diagnoses to tissue specimens collected during the surgery. While thoracotomy resulted in an accurate diagnosis in 83 percent of the cases, thoracoscopy was accurate 74 percent of the time. Computed tomography-guided procedure led to an accurate diagnosis in only 44 percent of the patients.
The researchers concluded, “an adequate specimen obtained from surgical biopsy increases the accuracy of subtype classification compared with radiological-guided biopsies.”