We have presented the case of borderline size AML (angiomyolipoma) of the kidney that had had been initially qualified for observation and had a serious complication caused by a rupture leading to a hematoma and subsequently to an operation. In the author's opinion a wider use of minimally invasive technologies in the prophylactic treatment of some cases of AML might prevent such complications and might make planning the treatment easier for the urologist and his patients.