According to GLOBOCAN 2018 statistics, each year there are
30,443 mesothelioma cases worldwide, and of those 30,443, 25,576 pass away. With close to 85 percent of those diagnosed succumbing
to the disease, mesothelioma remains one of the most deadly cancers as there is
no cure. However, surviving a mesothelioma diagnosis is not entirely impossible
as certain genetic and clinical factors play a part in determining how an
individual reacts to the disease and its treatment.
Scientists and researchers from the University of Pittsburgh
Medical Center (UPMC) recently published in the Lancet Respiratory Medicine six factors associated with higher percentages
of survival in patients suffering from mesothelioma. These factors have
remained largely unchanged throughout the nearly 30 years this study was conducted,
but continue to be relevant when finding the best course of treatment for this disease.
These six factors that contribute to better survival are as follows:
- Female
- Peritoneal mesothelioma
- Under 45 years of age
- Epithelioid subtype
- Stage 1 of disease
- Surgery
and chemotherapy
Data was collected from the National Mesothelioma Virtual
Bank. This bank was developed in 2006 and is responsible for gathering human
mesothelioma specimens for research. By
collecting paraffin embedded tissues, fresh frozen tissue, tissue microarrays,
blood samples, and geonomic DNA, research is then conducted research using
these specimens to study biomarkers, immunology, genetics, and therapeutics.
The National Mesothelioma Virtual Bank is at four facilities: New You
University School of Medicine, Mount Sinai School of Medicine, University of
Pennsylvania and, University of Pittsburgh Medical Center.
Between 1990 and 2017, 888 patients were studied to
investigate those six factors associated with survival.
Age and Gender
Age of diagnosis has always been a factor for those
suffering from mesothelioma. Generally, the younger a person is diagnosed, the
better the chances are for survival. The
average survival time is around 12 months after initial diagnosis, but for
those under the age of 45, rate of survival is about 59 months, or close to
five years. Those diagnosed at 75 or older may live on average of only 10
months.
Unfortunately, the vast majority of those suffering from
mesothelioma are older, as the average age of diagnosis is 69 years. This is because the latency period between
first exposure to asbestos and the time of diagnosis can span decades. Those
exposed to asbestos in their 20s may not have symptoms of mesothelioma or any
other asbestos-caused disease until after retirement – well into their 70s and beyond. On average, females have a
22-month survival.
Type of Mesothelioma
The mesothelium surrounding the lungs and lining the chest
cavity is called the pleura, so
mesothelioma affecting the cells lining the sacs surrounding the chest or lungs
is referred to as pleural
mesothelioma.
When the cancer affects the abdominal lining, or peritoneum, it is called peritoneal
mesothelioma.
Malignant peritoneal
mesothelioma is an extremely rare cancer. Only 100 to 500 cases are
diagnosed in the US each year, making up less than 30 percent of all mesothelioma cases. Like pleural mesothelioma, peritoneal
mesothelioma is often diagnosed when the malignancy is in the advanced stages.
However, the average survival time for those with peritoneal mesothelioma is
more than double than those with pleural mesothelioma – upwards of 30 months.
The cell type –
epithelioid, biphasic, and sarcomatoid – also may indicate survival rates.
Patients with sarcomatoid cell type are faced with a seven-month survival
median, while those with biphasic cell-type have an average of 10 months. Patients
with epithelioid sub type have the greatest advantage, as their median survival
is 18 months.
Stage of Disease,
Chemotherapy and Surgery
Those diagnosed with stage 1 mesothelioma have a higher rate
of survival than those diagnosed in the later stages of the disease. This is true
for almost all cancers, but with mesothelioma, it is seldom the cancer is found
in the early stages, which contributes to the high fatality rates associated
with the asbestos-caused cancer. Typically, mesothelioma is not detected until
symptoms begin. The median survival period is 20 months for those diagnosed
with stage 1 disease and 12 months for those with stages 3 and 4.
Despite promising results from clinical trials and immunotherapy
treatments, there is only one FDA approved chemotherapy treatment, pemetrexed. Surgery
is also used in the treatment of malignant mesothelioma. The doctor may remove
part of the lining of the chest or abdomen and some of the tissue around it and
depending how far the cancer has spread, a lung also may be removed. Those who
are able to receive both chemotherapy and surgery have a median survival of 23
months. However, surgery is not an option for those with mesothelioma. Patients
need to be in good overall health and strong enough to withstand such an invasive
procedure and the difficult recovery that follows. Fatality rates associated
with surgery for pleural mesothelioma are often higher.
The factors that contribute to an overall better survival
for those suffering from mesothelioma has largely remained unchanged over the
years. Getting diagnosed when younger, in earlier stages, and while in good
overall health has a tremendous impact on how the treatment of the disease moves
forward. However, research efforts continue to grow and scientists and
researchers are hopeful that with combination therapies, new treatments such as
immunotherapy, and upcoming clinical trials will offer new insight on how to
combat this fatal disease. Most recently, a $ 10.7 million grant was awarded to
the University of Pennsylvania for their continued research and understanding
of CAR-T
cell therapy.
Sources:
“Pleural Mesothelioma: Tacking a Deadly Cancer,” The Lancet
Respiratory Medicine (January 16, 2019). [Link]
Wagas Amin, et.al. “National Mesothelioma Virtual Bank: A
Platform for Collaborative Research and Mesothelioma Biobanking Resource to
Support Translational Research,” Lung Cancer International (September 2013). [Link]