Abstract: PD73-09
Sources of Funding: None

Introduction

The 4 cm size of renal anagiomyolipoma (AML) has been reported to increase the risk of pain and bleeding. It was our observation that many patients with renal AML of size > 4 cm are asymptomatic and are safely followed up without intervention. Here, we report 11 patients (pts) with renal AML of size of 10 cm or more, with the majority being treated conservatively.

Methods

Eleven pts with giant renal AML with size of 10 cm or more were identified in our records. Medical records of these patients were reviewed as regards to diagnosis, association with tuberous sclerosis, management and outcome.

Results

These were 7 females and 4 males with median age of 43 years (ranage:29-71). Five pts had tuberous sclerosis (TS) and 6 has sporadic renal AML. The 5 patients with TS have bilateral and multiple renal AML while 5 of the sporadic AML are unilateral and single and only one had 2 lesions in one kidney and a small one in the other kidney. The greatest diameter of the biggest lesion had a median of 15.5 cm (range: 10-32). Only one patient had significant pain associated with a lesion of 16 cm while the remaining patients were asymptomatic or had slight pain. Serum creatinine was normal in all patients with a median of 68 umol/L (range, 39-109). Big Aneurysms (>10 mm) were seen in 3 renal units (2 pts) with TS and required selective angioembolization that was successful. Partial nephrectomy was needed in 2 patients, one with significnat pain not relieved by selective embolization and another one explored for suspicious retroperitoneal liposarcoma. Everolimus was given to 4 patients, one of them , initially with huge bilateral multiple AML, extending from the diaphragm down to the pelvis, and with big hemorrhagic cystic lesion responded reasonably well with decrease of the size of AML and the associated hemorrhagic cyst. In the remaining 3 patients, the drug was discontinued because of side effects in 1, and no response in 2. At last follow up with a median duration of 68 months, all patients were asymptomatic and serum creatinine (median, 60 umol/L) remained within normal range, except mild increase in 2 pts, with no significant difference compared to its level at presentation (P =0.45). The CT at last follow up showed no significant big aneurysms and the greatest diameter of the biggest lesion is not significantly different from the one at presentation (p=0.9).

Conclusions

Big AML >10 cm remained stable in the majority of patients with conservative management. Renal function remained normal in the majority of these patients with long term follow up. Big aneurysms within AML can be successfully treated by superselective embolization. Nephron-sparing surgical excision of AML can be done for those with significant pain. The 4 cm cut off limit for conservative treatment should be revisited.

Funding

None