Management of oligometastatic non-small cell lung cancer patients: Current controversies and future directions

Abstract

Oligometastatic non-small cell lung cancer (NSCLC) describes an intermediate stage of NSCLC between localized and widely-disseminated disease. This stage of NSCLC is characterized by a limited number of metastases and a more indolent tumor biology. Currently, the management of oligometastatic NSCLC involves radical treatment (radiotherapy or surgery) that targets the metastatic lesions and the primary tumor to achieve disease control. This approach offers the potential to achieve prolonged survival in patients who, in the past, would have only received palliative measures. The optimal therapeutic strategies for the different scenarios of oligometastatic disease (intracranial vs extracranial disease, synchronous vs metachronous) remain undefined. Given the lack of head-to-head studies comparing radiotherapy to surgery in these patients, the decision to apply surgery or radiotherapy (with or without systemic treatment) must be based on prognostic factors that allow us to classify patients. This classification will allow us to select the most appropriate therapeutic strategy on an individualized basis. In the future, the molecular or microRNA profiles will likely improve the treatment selection process. The objective of the present article is to review the most relevant scientific evidence on the management of patients with oligometastatic NSCLC, focusing on the role of radiotherapy and surgery. We also discuss areas of controversy and future directions.

Keywords: Metastasectomy; Non-small cell lung cancer; Oligometastases; Radiosurgery; Stereotactic ablative radiotherapy; Stereotactic body radiation therapy.

Figure 1

Stereotactic body radiation therapy dose distribution for a single brain metastasis from non-small cell lung cancer. Planning computed tomography fused with magnetic resonance images. A: Coronal view; B: Axial view; C: Sagittal view.

Figure 2

Example of stereotactic body radiation therapy plan for adrenal gland metastases from non-small cell lung cancer with 95% isodose highlighted in dose heatmap. A: Coronal view; B: Axial view.

Figure 3

Image capture from stereotactic body radiation therapy planning session showing concentration of radiation dose to the liver metastases. Planning computed tomography fused with magnetic resonance images. A: Coronal view; B: Axial view.

Figure 4

Example of stereotactic body radiation therapy planning using 4D-computed tomography for a patient with right lung metastases from non-small cell lung cancer. A: Isodose distribution in the axial plane; B: Isodose distribution in the sagittal plane; C: Isodose distribution in the coronal plane.