Initial results from a phase II trial determined stereotactic radiation can increase the long-term survival for certain patients with stage IV cancers, according to a study published in the January issue of International Journal of Radiation Oncology • Biology • Physics.
Dwight E. Heron, MD, director of radiation services at UPMC Hillman Cancer Center in Pittsburgh, and colleagues enrolled 147 patients across three cancer centers in their phase II trial. The team evaluated the safety and effectiveness of stereotactic radiation for oligometastatic cancers. All participants had up to five metastases.
Following treatment, 84 percent of patients survived at least one year, and 43 percent survived five years or more. The median overall survival (OS) time was 42.3 months.
" …a small number of patients with stage-IV disease could have surgery to remove their metastases and live a long time. And so our question was, could we use highly focused radiation to destroy those tumors and have the same effect as surgery?" asked Heron in a Science Daily story. “The initial answer from this large prospective trial is yes."
Twenty-six percent of patients experienced complete remission, and partial remission occurred in another 26 percent. In 32 percent of patients their cancer did not change.
Additionally, those with breast (9 percent of patients), prostate (7.5 percent) and colorectal (21 percent) tumors survived longer than patients with primary lung (22 percent) or head and neck (11 percent) tumors.
Importantly, slightly less than 10 percent of patients experienced short-term toxicity of grade-2 or higher. One grade-3 case included trouble breathing, skin inflammation and anemia. And after a patient-reported quality of life (QoL) assessment, no participants noted significant changes in their quality of life following stereotactic therapy. There were zero reports at 6 weeks, 3 months and 9 months, and QoL improved at the 6- and 12-month mark.
“In this study, for patients with stage-IV disease, we have a treatment paradigm that can result in long-term survival while maintaining overall quality of life,” Heron said. “We had a sense this was the case from retrospective data, but the addition of prospective data is very convincing.”
Heron and colleagues plan to expand their current cohort of patients to nearly 200 participants and move forward with additional trials.
"In combination with immunotherapy, stereotactic radiation therapy may set a new bar for achieving better outcomes, lowering side effects and improving our patients' quality of life," Heron concluded.