Radiation Therapy Can Increase Mesothelioma Survival Time
July 30, 2018
Too many patients with malignant pleural mesothelioma are going without adjuvant radiotherapy that could extend their lives significantly, according to Dr. Bin Teh at Houston Methodist Hospital in Texas.
Teh is the senior author of a recent study — the largest of its kind — that examined the role and extent of radiation therapy in the overall treatment of mesothelioma.
He and his colleagues found only 3.1 percent of patients diagnosed with pleural mesothelioma underwent radiotherapy treatment in combination with aggressive surgery.
“Surgery plus radiation improves overall survival,” Teh, vice chair of the Department of Radiation Oncology at Houston Methodist, told Asbestos.com. “I was surprised at how little it was used overall. I would really like to see more than 3 percent receiving this treatment safely.”
National Cancer Database Numbers
Their retrospective study was done by using the National Cancer Database (NCDB), a joint project of the American Cancer Society and the American College of Surgeons.
It typically represents an estimated 70 percent of cancers nationwide.
The study was published in the June issue of International Journal of Radiation Oncology.
“The goal with radiation is to prevent disease from coming back after surgery,” Teh said. “With mesothelioma, it is really important to do it at a specialty center with experience.”
Researchers went back more than two decades in the database to find 24,914 mesothelioma patients who met the inclusion criteria.
Not Enough Doctors Utilizing Radiotherapy
Researchers found 69.3 percent of the patients received no local therapy, 23.8 percent underwent surgery and only 3.1 percent received surgery plus radiation.
What they also found was the benefit of a surgery and radiation combination was significant.
Median Overall Survival
No Local Therapy: 7.5 months
Surgery Alone: 16.6 months
Surgery and Radiation: 21.4 months
One-Year and Two-Year Survival Rates
No Local Therapy: 35.9 percent and 16.6 percent
Surgery Alone: 60.2 percent and 38.8 percent
Surgery and Radiation: 76.5 percent and 42.7 percent
The number of patients getting radiation treatment did not include those receiving it without surgery in a palliative setting.
“The biggest takeaway is that if patients are in good enough shape — remember these are intense surgeries — they are candidates for additional treatment,” said Dr. Gary Lewis, radiation oncologist at The University of Texas Medical Branch and lead study author. “And that radiation can potentially improve survival.”
Reasons Vary for Bypassing Radiotherapy
Although there was no differentiation in the study data, there are multiple reasons why patients are not getting radiotherapy after surgery, according to the doctors.
Some patients are not well enough, or strong enough, after aggressive surgery to endure another round of treatment.
Some cancer centers where the surgery was performed do not have the latest radiation technology — or a radiologist experienced with mesothelioma patients — to do it safely.
And some referring physicians are not yet believers in the latest radiotherapy techniques.
“Historically, radiation has resulted in a fair amount of toxicity. It’s still viewed as a crude way of treating these patients, in the minds of some practicing, referring physicians,” Lewis said. “However, with these newer techniques, this newer technology, we can avoid the toxicity, making it more effective and safer.”
Find a Specialty Center
At Houston Methodist and at a number of the larger cancer centers, radiation oncologists like Teh are using image-guided intensity-modulated radiation therapy (IG-IMRT), which is considerably more precise.
The surgery and radiotherapy combination in the past was used mostly with the extrapleural pneumonectomy procedure, which involves removing the entire diseased lung.
The more exact IG-IMRT now enables it to also be used with the lung-sparing pleurectomy and decortication surgery.
“Radiation with mesothelioma needs to be done at an institution with experience, expertise and the right technology,” Teh said. “That’s when it can be done safely and likely more often.”