Doctors at the University of Toronto compared the thickness of pleural mesothelioma tumors in 65 patients who had not yet received any treatment with their eventual outcomes and found a definite correlation.
Summarizing their research in The European Respiratory Journal, the team called their findings “extremely encouraging” because of their potential to help direct treatment for the best mesothelioma outcomes.
Setting up the Research
All of the patients in the new study had been chosen to undergo “surgery for mesothelioma after radiation therapy”, also known by the acronym SMART.
The total thickness of each patient’s mesothelioma tumors was determined by measuring the maximum thickness on nine specific spots on the chest wall, the mediastinum (membrane that separates the lungs), and the diaphragm.
The average thickness of each patient’s tumors, when combined, was 6.9 centimeters. That number correlated with the total volume of their mesothelioma tumors and the amount of metabolic activity going on in those tumors as indicated by their uptake of a radioactive tracer during imaging studies.
Tumor Thickness and Mesothelioma Outcomes
After 19 months, 40 of the 65 patients (62%) had experienced a recurrence of their pleural mesothelioma and 36 (55%) had died. On average, the patients who had died are those who had the highest total tumor thickness.
“Total tumour thickness had a significant impact on overall survival and disease-free survival in univariate analysis,” writes thoracic surgeon Marc de Perrot, MD, MSc, of Toronto General Hospital. “In multivariate analysis, total tumour thickness remained an independent predictor of survival…”
Other predictors of mesothelioma survival included having the epithelioid subtype and whether or not the cancer had spread to the lymph nodes. The thickness of mesothelioma tumors on the diaphragm correlated most closely with time to death.
Making Sense of the Findings
Choosing which patients are good candidates for specific mesothelioma therapies is one of the most challenging aspects of mesothelioma care.
The Canadian team calls their research “extremely encouraging” because tumor thickness appears to be a factor that may help make treatment decisions more clear-cut for mesothelioma patients and doctors.
In the conclusion of their summary, Dr. de Perrot and his colleagues say tumor thickness could potentially be used “to refine the clinical staging of malignant pleural mesothelioma and optimize patient selection for radical treatment.”
De Perrot, Marc, et al, “Impact of tumour thickness on survival after radical radiation and surgery in malignant pleural mesothelioma”, March 15, 2017, European Respiratory Journal