For patients with unresectable stage III non–small cell lung cancer (NSCLC), concurrent proton therapy and chemotherapy may offer better survival outcomes and less toxicity than the standard of care, according to a recent clinical trial from The University of Texas MD Anderson Cancer Center.
The single-institution phase II trial enrolled 64 patients with unresectable stage IIIA or IIIB NSCLC who had not undergone previous radiation therapy to the chest. All patients received carboplatin and paclitaxel with concurrent passively scattered proton beam therapy.
“We hypothesized that proton therapy would offer a survival benefit to patients and reduce treatment-associated toxic effects, which can be very serious,” said Joe Chang, M.D., a professor in the Department of Radiation Oncology and the trial’s principal investigator.
The 26.5-month median overall survival duration for patients in the trial was substantially longer than the historical median overall survival duration of 16.0 months (at the time of the trial’s design) for similar patients treated with chemotherapy and concurrent photon-based radiation therapy.
The toxic effects experienced by patients in the trial included grade 2, 3, and 4 esophagitis and grade 2 and 3 pneumonitis. The rates of these effects were lower than those in previous studies of chemotherapy and concurrent photon-based radiation therapy. Unlike patients in some previous studies of the standard treatment, none of the patients in the trial died of toxic effects.
These results, which represent the longest follow-up to date of stage III lung cancer patients who received proton therapy, were recently published in JAMA Oncology.
Dr. Chang noted that since the trial began, the delivery of both photon-based radiation therapy and proton therapy have improved, thereby reducing the rate and severity of both treatment modalities’ adverse effects. To determine how these improvements will affect survival, MD Anderson researchers are now enrolling patients with stage II or III NSCLC in a randomized phase II trial (No. 2011-1058) of chemotherapy with concurrent photon-based or proton-based intensity-modulated radiation therapy (see Proton Therapy for Non–Small Cell Lung Cancer, OncoLog, June 2016).