Real-world management of TSC-associated renal angiomyolipomas

TSC (Tuberous Sclerosis Complex) affects multiple organ systems, but kidney health represents one of the most significant long-term concerns for adults living with TSC. Non-cancerous kidney tumours called renal angiomyolipomas (AMLs) are common in TSC and can cause complications, including internal bleeding and loss of kidney function. The following summary outlines key insights from a long-term research study exploring how these kidney tumours are managed in real-world clinical practice and the impact that mTOR inhibitor medications can have on reducing complications over time.

About this study

While clinical trials have already demonstrated that mTOR inhibitors, such as everolimus, can help manage renal AMLs in TSC, real-world evidence regarding their long-term ability to prevent major clinical complications, specifically kidney bleeding and the need for invasive procedures, has remained limited. This study evaluated how renal AMLs are managed in routine clinical practice across 3 major hospitals in France, examining the long-term impact of mTOR inhibitor therapy on bleeding rates, invasive procedure requirements, and overall kidney outcomes in adult patients.

How the study was conducted

This study focused on 96 adult patients with TSC treated at 3 tertiary hospital centres in France. Total follow-up across the primary group covered 694.3 patient-years, with an average follow-up of 7.3 years per patient. Researchers tracked kidney-related complications such as severe bleeding, urinary tract obstruction, and kidney function loss, as well as procedures including selective arterial embolisation and surgeries. For the 39 patients who initiated mTOR inhibitor therapy, with nearly 95% taking everolimus, the study split their data into pre-treatment and post-treatment periods to directly compare complication and procedure rates before and after starting the medication.

Outcomes of the study

Initiation of mTOR inhibitor therapy was associated with an 89% reduction in AML-related bleeding rates. Following treatment initiation, the need for selective arterial embolization, a procedure that blocks the blood vessels supplying AMLs to reduce their blood supply and risk of bleeding, decreased by 90%. Medications were generally well tolerated under real-world conditions. Although side effects such as mouth sores and elevated protein levels in the urine were reported in over 50% of the patients, fewer than 3 permanently discontinued the drug. Despite these benefits, nearly 60% of the patients in the cohort never received mTOR inhibitor therapy. At their last assessment, many of these untreated patients still presented with high-risk imaging features such as large tumour size or aneurysms and experienced ongoing complications that likely could have been prevented.

Conclusions of the study

In a real-world, long-term setting, mTOR inhibitor therapy suppresses the bleeding burden of TSC-associated renal AMLs and minimises the need for repeated invasive embolisations. The authors found that delays in renal care are common across health systems, as patients are typically diagnosed with TSC in childhood but are often not referred for specialist renal management until after 30 years of age, when multiple large AMLs measuring 3cm or greater are already established.

Implications of the study

Clinicians and multidisciplinary TSC care teams need to proactively screen and manage kidney involvement rather than deferring treatment until after a major bleeding event occurs. Standardised imaging tools should be systematically used to identify high-risk AMLs early, allowing for timely nephrology referral and medication initiation. Ultimately, by reducing the need for repeat arterial embolisations and surgical interventions, early use of mTOR inhibitors may help prevent cumulative kidney tissue loss and protect long-term renal function.

These findings also highlight the importance of proactive kidney surveillance and management for people living with TSC. Adults with TSC, as well as parents and carers, can play an important role in advocating for regular monitoring as part of an individualised TSC management plan. International recommendations include abdominal MRI every 1–3 years to monitor for renal AMLs and other kidney complications, along with at least annual monitoring of blood pressure, kidney function and protein in the urine. Through the advocacy efforts of TSA and others, abdominal MRI has been available on the Medicare Benefits Schedule (MBS) since July 2024 for people living with TSC, improving access to recommended renal surveillance in Australia.

DISCLAIMER

This information is intended to provide some insights into recent TSC-related research.  It is not intended to, and it should not, constitute medical or other advice.  Readers are warned not to take any action without first seeking medical advice.

Gemander N, Dao M, Kalbacher E, Fantoni JC, Provot F, Correas JM, Joly D. Real-world management of tuberous sclerosis complex-associated renal angiomyolipomas: the impact of mTOR inhibitors. Clin Kidney J. 2026 Mar 3;19(4):sfag072. doi: 10.1093/ckj/sfag072. PMID: 41982247; PMCID: PMC13076030.
https://pmc.ncbi.nlm.nih.gov/articles/PMC13076030/