Video-Assisted Pleural Biopsy for Mesothelioma is Not Always Accurate

New research shows some patients are more likely to get an accurate mesothelioma diagnosis from video-assisted pleural biopsy than others. 

Cancer doctors at Japan’s Hyogo College of Medicine conducted the new research. It included four hundred patients with suspected pleural mesothelioma.  

The researchers found that certain conditions can affect the accuracy of video-assisted pleural biopsy. Patients with early stage mesothelioma, a lot of inflammation, or fibrous connective tissue around their tumors were more likely to be misdiagnosed.

Biopsy for Mesothelioma Diagnosis

VATS is the acronym for video-assisted thoracoscopic surgery. It is a minimally-invasive surgical technique to diagnose problems in the chest. Mesothelioma tumors grow on the membrane around the lungs (pleura). Doctors may use the video-assisted pleural biopsy technique to take some tissue from the tumor.

Mesothelioma is notoriously challenging to diagnose. Many patients have no symptoms until the disease is in an advanced stage. When symptoms like coughing and chest pain do appear, they may be mistaken for other conditions. 

Mesothelioma biomarker tests may help confirm a suspected case. But video-assisted pleural biopsy is still the only way to know for sure if a patient has mesothelioma. 

Testing the Accuracy of Video-Assisted Pleural Biopsy

Video-assisted pleural biopsy is one of the best tools for mesothelioma diagnosis. But the new study shows that it is not foolproof. The study found that ten percent of mesothelioma cases were misdiagnosed with this technique. 

The goal of the study was to see why the technique worked better in some people than in others. The researchers reviewed the cases of 400 consecutive patients suspected of having pleural mesothelioma. Patients came to the hospital between 2004 and 2017.

Almost 70 percent of the 400 patients received a mesothelioma diagnosis after video-assisted pleural biopsy. Twenty-five patients had metastatic carcinoma and 6 had benign pleural disease.

The remaining 102 patients who had a VATS biopsy got one of two diagnoses. These patients learned that they had either atypical mesothelial proliferation (AMP) or non-specific pleuritis (NSP).

Additional tests showed that 9.8 percent of those diagnoses were wrong. 

Conditions that Impact VATS

In every case where video-assisted pleural biopsy was not accurate, it was because the surgeons could not get enough tissue. 

Sometimes, it was because the tumor was too small. In other cases, there was too much inflammation in the chest. The third reason a surgeon might not be able to take enough tissue was desmoplasia. This is when dense connective tissue forms around a tumor. 

The researchers conclude that video-assisted pleural biopsy of mesothelioma is most challenging in these situations. The study may help doctors put biopsy results into perspective in mesothelioma patients with these issues. 

Source:

Hashimoto, M, et al, “Clinical feature of diagnostic challenging cases for pleural biopsy in patient with malignant pleural mesothelioma”, January 24, 2020, General Thoracic and Cardiovascular Surgery, Epub ahead of print, https://link.springer.com/article/10.1007%2Fs11748-020-01295-5