Pleural mesothelioma is a cancer that originates in the lining of the lungs as a result of asbestos exposure. The United States implemented asbestos regulations in the 1970s to protect the public from exposure, but people continue to be diagnosed with mesothelioma and other asbestos diseases. Due to pleural mesothelioma’s latency period, researchers previously suggested the annual diagnosis rate would peak between 2000 and 2005.
However, a recent study suggests pleural mesothelioma rates in the 21st century have not declined. Researchers found annual cases of pleural mesothelioma remained unchanged from 2004 to 2014. Despite the stable incidence of the disease, the study also found survival rates are slowly improving.
Researchers Study Pleural Mesothelioma Incidence
Pleural mesothelioma is the most common type of mesothelioma cancer, accounting for 80% to 90% of diagnoses. Because it is the most common, it has been a focus of mesothelioma research. In a recent study, researchers at the Taussig Cancer Center at the Cleveland Clinic analyzed data from 20,988 pleural mesothelioma patients in the National Cancer Database (NCDB).
The study analyzed incidence, treatment and survival rate among pleural mesothelioma patients from 2004 to 2014. Multiple patient demographics, including age, sex, income, health insurance and medical history, were also evaluated.
Ultimately, researchers found the annual number of pleural mesothelioma diagnoses has remained stable. During the 10-year period, the study noted:
- The pleural mesothelioma diagnoses per year increased from 1,783 in 2004 to 1,961 in 2014.
- The sex distribution of patients remained constant (20% female, 80% male).
- The proportion of elderly patients increased from 75% to 80%.
- The percentage of patients undergoing treatment increased from 34% to 54%.
Despite many pleural mesothelioma statistics remaining steady, the study found improving survival rates. Researchers noted this change may be due to a number of factors, including improved treatment options.
Pleural Mesothelioma Survival Rate Is Improving
Although rates of diagnosis are steady, researchers agree patient survival rate is improving. Due to earlier detection and new forms of treatment, pleural mesothelioma patients are living longer. The study showed from 2004 to 2014:
- Patients’ 1-year survival rate increased from 37% to 47%.
- Patients’ 3-year survival rate increased from 9% to 15%.
These findings correlate with other studies that suggest improving pleural mesothelioma survival rates.
The study from the Cleveland Clinic specified several factors that likely contributed to improved survival. The study noted patients with health insurance coverage and those treated in an academic center lived longer. Younger age, female sex and higher income were also associated with improved survival rates.
In addition to these factors, the researchers noted advancements in treatment, particularly multimodal therapy, led to improved pleural mesothelioma survival.
Developments in Mesothelioma Treatment
An increase in pleural mesothelioma survival rate can be linked to earlier detection, as well as more multimodal therapy options and emerging treatments. Multimodal therapy is the combination of two or more different forms of cancer treatment.
Advancements in technology have also aided in survival rate by better detecting malignant mesothelioma. A patient’s prognosis can depend on the stage of mesothelioma at diagnosis. Pleural mesothelioma patients diagnosed at earlier stages of the disease have higher survival rates.
Research through mesothelioma clinical trials has continued to make a difference in patient survival rate. Mesothelioma prognosis is typically 12 – 21 months, but some recent clinical trials have been successful in improving life expectancy.
In recent years, immunotherapy, in particular, has shown promise for pleural mesothelioma.
One clinical trial studied the efficacy of CAR-T therapy with PD-1 immunotherapy for 14 pleural mesothelioma patients. This type of treatment involves genetically modifying white blood cells, so the immune system can better recognize and fight cancer cells.
The trial found five patients achieved partial responses and four had stable disease. This means cancer did not grow or spread during treatment. Additionally, two patients achieved a complete response, indicating no active cancer was detected. Both outlived their initial prognosis.
Other clinical trials testing immunotherapy and other promising emerging treatments are ongoing. Further developments in treatment have the potential to improve life expectancy and increase the quality of life for mesothelioma patients.
Calculating the Future of Pleural Mesothelioma
Tightened regulations, along with a growing awareness of the dangers of asbestos and where the mineral may still exist today, can prevent future diagnoses. Experts at the Centers for Disease Control and Prevention (CDC) and other advocates support continued monitoring and regulations to further prevention. In the meantime, doctors and scientists around the world are continuously working to improve treatment and find a cure.