Abstract:

Objective To discuss the distinctive sonographic feature and the biological behavior of renal angiomyolipoma （RAML）， and to provide the reference for the clinicians to make the accurate diagnosis of RAML. Methods The clinical data of one patient with invasive classical RAML combined with pseudaneurysm formation were collected. The sonographic appearances were analyzed in conjunction with the pathological characteristics to clarify the biological behavior of RAML， and the relevant literatures were reviewed. Results The patient， a 60-year-old female， visited the local hospital due to discomfort in the lumbar area，and received CT examination，and the CT examination results revealed a left renal mass，so the patient came to our hospital. The specialist clinical examinations and laboratory investigations were unremarkable. The ultrasound results indicated an enlarged left kidney with a cystic and solid mass at the upper pole， which featured pseudaneurysm formation （originating from the interlobar arteries）； the enhanced CT image results suggested a high probability of upper pole renal carcinoma combined with aneurysmal formation within the tumor， alongside invasion into the left adrenal gland. The patient underwent laparoscopic radical left nephrectomy， and the postoperative pathology confirmed the diagnosis of invasive classical RAML. Conclusion The classical RAML can exhibit the invasive biological behavior. The pseudaneurysm formation is a special sonographic manifestation of RAML， which can be challenging to differentiate from the other renal tumors.

Key words: Renal angiomyolipoma, Invasion, Pseudoaneurysm, Ultrasound examination