American Radium Society® (ARS) Appropriate Use Criteria on Radiation Therapy in Oligometastatic or Oligoprogressive Non-Small Cell Lung Cancer (NSCLC)
Amini A, Verma V, Simone C, Chetty I, Choi JI, Chun S, Donington J, Edelman M, Higgins K, Kestin L, Mohindra P, Movsas B, Rodrigues G, Rosenzweig K, Rybkin I, Shepherd A, Slotman B, Wolf A, and Chang J. American Radium Society® (ARS) Appropriate Use Criteria on Radiation Therapy in Oligometastatic or Oligoprogressive Non-Small Cell Lung Cancer (NSCLC). International Journal of Radiation Oncology Biology Physics 2020; 108(2):E48.
International Journal of Radiation Oncology Biology Physics
Background: Recently, small randomized phase II studies have demonstrated significant improvements in progression free survival (PFS) and overall survival (OS) with the addition of stereotactic body radiation therapy (SBRT) in stage IV non-small cell lung cancer (NSCLC) patients with oligometastatic disease. Yet, current guidelines on local therapy for oligometastatic disease are lacking.
Objectives: The American Radium Society (ARS) Appropriate Use Criteria Thoracic Panel was assigned to create guidelines on consolidative local therapy (radiotherapy, surgery, and others) recommendations for oligometastatic and oligoprogressive NSCLC patients.
Methods: A panel of radiation, medical, and surgical oncologists at academic and private practices evaluated best practice based on the current available data on the following topics/scenarios: 1) defining oligometastasis and oligoprogression, 2) role of radiation in oligometastatic disease in the up-front setting, 3) role of consolidative radiation after stable/partial response following upfront systemic therapy, 4) management of the primary and N1-N3 nodal disease, 5) role of consolidative radiation for oligoprogression during systemic therapy, 6) role of consolidative radiation for cases with targetable driver mutations, and 7) management of brain metastases in the oligometastatic or oligoprogressive setting.
Results: Based on current data and consensus by the expert panel, the optimal definition of oligometastatic and oligoprogression is ≤3 metastatic deposits, not including the primary tumor, with the understanding that ongoing trials may alter this threshold. In the scenario of radiation for oligometastatic disease in the up-front setting, several single-arm prospective trials support this approach and, therefore, this may be one feasible approach, although most contemporary randomized studies along with ongoing phase III trials are designed with standard of care systemic therapy in the upfront setting, followed by locally ablative therapy (LAT). Two randomized controlled phase 2 studies have demonstrated that the addition of local consolidative RT or surgery for oligometastatic NSCLC improved PFS and OS. Therefore, the panel supports the utilization of LAT as an option following upfront systemic therapy in oligometastatic patients. Thoracic nodal treatment is also discussed with various radiation approaches, including hypofractionation and SBRT. Prospective data on SBRT for oligoprogression are limited, but there is some suggestion that LAT may be beneficial in select patients. In patients with targetable mutations, a similar approach should be offered, although the consensus panel acknowledges a low sample size of these patients in existing trials. Lastly, the treatment of brain metastases should be based on multiple factors including the number of metastases, patient symptoms, and presence of a molecular target.
Conclusions: The guideline topics discussed here are the first in the management of oligometastatic and oligoprogressive NSCLC based on a multidisciplinary panel of physicians. Finalized recommendations from the committee will be presented at the annual ARS meeting.