Adrenal Oligometastases Secondary to Non-small Cell Lung Cancer—What is the Optimal Treatment Approach?

Background: Five-year overall survival (OS) for patients with stage IV non-small cell lung cancer (NSCLC) is a dismal 1%. However, approximately 7% have limited or solitary metastases, including to the adrenal gland. Radical treatment of these oligometastases (OM) could increase local control and improve OS. Our objective was to critically analyze data describing aggressive treatment of adrenal OM secondary to NSCLC. Methods: A literature search examining English publications describing surgery or radiotherapy (RT) was performed, supplemented by searching reference lists. Case reports of three or fewer patients, and articles from which NSCLC- or adrenal-specific clinical outcomes could not be abstracted, were excluded. Results: Twenty-nine studies met eligibility criteria (521 patients), 26 retrospective. No publications directly compare modalities. Four surgery studies described contemporaneous patients treated with palliative chemotherapy (CH) alone. Reported median OS ranged from 9.5–64 months after adrenalectomy, 8–23 months after RT, and 6–8.5 months after CH. Local failure after surgery was 14%, with response rates after RT 57–75%. Both appear well-tolerated. Conclusions: In patients with an adrenal OM secondary to NSCLC, aggressive treatment should be considered. However, due to the paucity of high quality evidence, it is unclear at present whether this approach alters the natural history of the disease.