Renal angiomyolipomas, which occur in about two-thirds of Tuberous Sclerosis Complex patients, are histologically benign hamartomas consisting of varying amounts of vascular tissue, fat and smooth muscle. The prevalence of renal hamartomas with Tuberous Sclerosis Complex increases with age, and in adults bilateral tumors or more than one tumor in a single kidney are common. Patients with Tuberous Sclerosis Complex and renal angiomyolipomas have a 7% greater risk of developing renal carcinoma than individuals with renal angiomyolipomas who do not have TSC.

Diagnostic Screening and Follow Up

Both renal angiomyolipomas and cysts are often asymptomatic and may require no treatment. Renal failure may result from obstructive uropathy or when much of the normal renal parenenchyma is displaced. Hematuria, flank or abdominal pain, or retroperitoneal hemorrhage can be the initial signs of kidney problems. At diagnosis of TSC, a renal ultrasound or CT should be performed to look for renal angimyolipomas and/or cysts. If there are questionable results from the tests, a renal MRI should be performed. If the patient is an infant at diagnosis, a repeat ultrasound or CT should be performed at least every 3 years throughout the patient’s life to monitor the kidneys, unless the patient is symptomatic. Once the patient is symptomatic, the frequency of the scans should be dictated by the kind and severity of the symptoms. Blood pressure should be monitored at every visit, and appropriate medications prescribed if high blood pressure is present.


Renal lesions in many patients remain stable and require no specific treatment. Renal tumors must sometimes be removed because of rapid tumor enlargement or to alleviate obstruction; whenever possible in these patients, a limited operation which spares some of the kidney should be considered. In extreme cases, it may be necessary to remove an entire kidney. Systemic hypertension due to TS-related renal disease can usually be effectively treated with medication, and medical management of pending renal failure may delay the need for dialysis. Renal transplantation has been successfully performed in patients with Tuberous Sclerosis Complex who lose function of both kidneys.

Kidney Cancer Canada

Also for more information on kidneys you can visit Kidney Cancer Canada’s website at:



This information © of the Tuberous Sclerosis Alliance and used with permission 2014. All rights reserved.