Retrospective Analysis of Efficacy and Toxicity of Stereotactic Body Radiotherapy and Surgical Resection of Adrenal Metastases from Solid Tumors

Simple Summary The adrenal glands represent a frequent localization area for metastases of various primary tumors. The standard of care for treating adrenal metastases is currently surgical resection, but radiotherapy is becoming a feasible and well-tolerated treatment alternative. However, the literature shows contradictory results regarding the optimal local treatment for adrenal metastases. This study analyzed oncological outcomes (local control, progression free survival, and overall survival) and complication rates after stereotactic body radiotherapy or surgical resection of adrenal metastases to further asses the benefits of stereotactic body radiotherapy. To our knowledge, this analysis is the first direct comparison of stereotactic body radiotherapy and adrenalectomy for adrenal metastases.Abstract Background: This single-center retrospective study aimed to evaluate the efficacy and toxicity profiles of stereotactic body radiotherapy (SBRT) and surgical resection in patients with adrenal metastases originating from solid tumors. Methods/Materials: Patients with advanced tumor conditions or comorbidities typically received SBRT, whereas those considered physically fit underwent standard surgical treatment. Endpoints included local control (LC), progression free survival (PFS), overall survival (OS), and complication rates (CR). Results: 41 patients with 48 adrenal metastases were included, with 27 (65.9%) patients receiving SBRT and 14 (34.1%) patients undergoing adrenalectomy. One- and two-year LC values were 100% for both periods after adrenalectomy, and 70.0% and 52.5% after SBRT (p = 0.001). PFS showed values of 40.2% and 32.1% at one and two years after adrenalectomy and of 10.6% for both periods after SBRT (p = 0.223). OS was 83.3% both one and two years after surgery and 67.0% and 40.2% after SBRT (p = 0.031). There was no statistically significant difference between the two groups regarding acute complications (p = 0.123). Conclusion: Despite potential confounders, adrenalectomy exhibited statistically significant superior LC and OS compared to SBRT in managing adrenal metastases, while both treatment methods displayed acceptable toxicity profiles. However, patient selection bias must be taken into account when directly comparing the two therapy modalities. Nevertheless, the study provides new and important results for the scientific and medical communities regarding oncological outcomes after SBRT or surgical resection of adrenal metastases.