Effects of everolimus on tuberous sclerosis complex-associated renal angiomyolipoma

Aim: Tuberous sclerosis complex (TSC) presents with multisystem benign neoplasm induced by dysregulation of the mammalian target of rapamycin pathway. This study aimed to examine the effects of oral everolimus at either 2.5 or 5.0 mg daily on the treatment of TSC-associated renal angiomyolipoma (AML). Methods: Between July 2012 and August 2015, patients with TSC-associated renal AML were selected for everolimus therapy protocol. An oral everolimus starting dose at 2.5 mg was administered daily, and was gradually increased to 5.0 mg daily. All patients were evaluated using magnetic resonance imaging or computed tomography scanning at baseline, 12, 24, and 36 months after the start of treatment for measuring the changes of renal AML mass volume. Results: Eight patients were finally enrolled for analysis in this study. Everolimus treatment had a statistically significant effect on the renal AML volume reduction during follow-up (P < 0.05). Renal AML mass volume reduction rates were 10.5–45.3% in four patients with everolimus 2.5 mg and 40.7–73.1% in four patients with everolimus 5.0 mg daily; the difference was statistically significant between the two groups (P < 0.05). Longitudinal follow-up for response to everolimus showed volume reduction rates to be around 10.5–73.1% in the initial 6–24 months after everolimus treatment, which remained stable during follow-up up to 36 months. Conclusion: The results suggest that an oral everolimus is effective and provides a non-invasive way to treat TSC-associated renal AML, and patients are likely to require maintenance therapy to continue to derive benefit.