Intensity-modulated radiotherapy (IMRT) was found to be less dangerous and more effective than standard conformal radiotherapy in treating malignant pleural mesothelioma (MPM), a recent study reports.
A team of researchers at Gazi University in Turkey published the study, titled “Intensity-Modulated Radiation Therapy Improves the Target Coverage Over 3-D Planning While Meeting Lung Tolerance Doses for All Patients With Malignant Pleural Mesothelioma,” in the journal Technology in Cancer Research & Treatment.
Pleural mesothelioma is a cancer that grows on the lining of the lungs. Because these membranes are in close contact with other organs, targeting mesothelioma tumors with radiation therapy may also damage those organs.
The IMRT treatment strategy was to expose the tumors to seven to nine beams of radiation, coming at different angles, at a dose ranging from 1.8 to 50.4 Gy (a measure of radiation dosage).
The study included 12 patients with MPM who received IMRT on one side of their chests. The treatment plan was designed to avoid damaging nearby organs with the radiation.
The research team found that when IMRT was used, the tumors were exposed to higher doses of radiation to kill the cancer, but the surrounding healthy lung tissue was spared, compared to standard conformal radiotherapy, which is designed to shape radiation beams to match the shape of the tumor.
The team also found that the dose of the radiation was more evenly distributed using IMRT and covered the target tumor tissue more completely.
“Intensity-modulated radiation therapy was statistically superior in target coverage and dose homogeneity,” Sukran Ulger, MD, a radiation oncologist and part of the medical faculty at Gazi University, said in a press release.
“To overcome high local-regional recurrence, IMRT appears to be the only option for irradiating the target volume with an efficient radiation dose,” the researchers wrote.
“In summary, with a large and complex target volume of MPM, IMRT has the ability to deliver an efficient tumoricidal radiation dose while keeping lung dose below tolerance for pneumonitis,” they concluded. “Reported lower local recurrence rates of IMRT (13%) in MPM render this irradiation technique necessary for [chest] RT. With increasing knowledge of both IMRT and MPM, we will be able to implement more complex and strict radiation treatment plannings.”