Objective  This study aimed to investigate the strategy for surgical treatment of complex renal angiomyolipoma (AML).

  Methods  The clinical data from 14 patients with complex renal AML confirmed by surgery and pathological examination in Peking Union Medical College Hospital from January 2015 to March 2018 were retrospectively collected and analyzed, including clinical and imaging features, surgical methods, and perioperative management strategy. The changes in CT imaging and renal function before and after the operation were compared and the effect of surgical methods on the renal function was analyzed.

  Results  Among 14 patients with renal AML, 1 had a relative solitary kidney with AML, 7 had multiple AML, 8 had huge AML (the maximum diameter of the tumor >7 cm), 6 had AML adjacent to the renal collection system or the renal portal, and 2 had AML combined with bleeding and rupture history; all cases were complicated and difficult to treat. All operations were successfully performed by laparoscopic or open partial nephrectomy or enucleation of the tumor, and pathological examination indicated renal AML. All patients were regularly followed up and no recurrence was found by CT scanning. The renal function of all patients was well preserved; the concentration of serum creatinine before and 1 month after the operation were (84.1±26.8)μg/ml and (97.5±37.0)μg/ml respectively, without statistically insignificant difference (t=-3.193, P>0.05).

  Conclusions  Complex renal AML is difficult to operate. The effect of partial nephrectomy or enucleation of the tumor is definite; these strategies might maximally, safely, and effectively reserve nephrons.