The American Society for Radiation Oncology (ASTRO) and European Society for Radiotherapy & Oncology (ESTRO) have released the first clinical guideline on the use of definitive local therapy, including radiation and surgery, for the treatment of patients with oligometastatic non–small cell lung cancer (NSCLC).1,2
The guideline published in Practical Radiation Oncology stated that a multidisciplinary approach is needed to guide treatment decisions for patients with oligometastatic NSCLC. Treatment for oligometastatic NSCLC has historically involved systemic therapy with chemotherapy or immunotherapy, and local therapy has traditionally been used only for palliation and symptom relief. However, expanding data point to a larger role for definitive local therapy to all disease sites to elicit durable tumor control and improved survival outcomes.
“Oligometastatic NSCLC is a phase in lung cancer development that may offer us new opportunities to improve patient outcomes, because it typically is more treatable than widely metastatic cancer,” Puneeth Iyengar, MD, PhD, co-chair of the guideline task force and an associate professor of radiation oncology at UT Southwestern Medical Center in Dallas, stated in a news release. “The research on local therapy for oligometastatic cancer is still at a relatively early stage, but we already see indicators of potential benefits for patients. Adding local therapy to systemic therapy may lead to more durable cancer control, potentially improving progression-free survival, overall survival, and quality of life.”
The guideline task force recommended the integration of definitive local therapy only for patients with 5 or fewer distant extracranial metastases, and that local therapy should be used only when it is feasible and clinically safe for all disease sites. The addition of definitive local therapy to standard-of-care systemic therapy is conditionally recommended for carefully selected patients with synchronous oligometastatic, metachronous oligorecurrent, induced oligopersistent, or induced oligoprogressive conditions for extracranial NSCLC.
Additionally, radiation and surgery are the only recommended modalities for definitive local treatment of patients with oligometastatic NSCLC. Regarding the sequencing and timing of local therapy and systemic therapy, up-front definitive local treatment is recommended for patients with symptomatic metastases. At least 3 months of systemic therapy is recommended prior to the start of definitive local therapy for asymptomatic patients with synchronous disease.
The task force also recommended that guidelines from the National Comprehensive Cancer Network and the European Organization for Research and Treatment of Cancer be consulted when determining optimal staging, radiation dosing, treatment planning, and delivery techniques. Pathological confirmation of metastases is also recommended, and the guideline included a preference for hypofractionated radiation therapy or stereotactic body radiation therapy when appropriate.
The guideline also addressed the incorporation of local therapy into standard treatment for patients whose disease returns or spreads after definitive local therapy for oligometastatic NSCLC.
Notably, intracranial metastases were not included in the guideline.
The guideline was developed through a systematic literature review of articles published through February 2022. The ASTRO/ESTRO task force included radiation, medical and surgical oncologists, a radiation oncology resident, a pulmonologist, thoracic surgeons, a medical physicist, and a patient representative.
The Royal Australian and New Zealand College of Radiologists and the Canadian Association of Radiation Oncology have endorsed the guideline.