I. Vascular smooth muscle lipoma (AML) is of common mesenchymal origin, most commonly seen in the kidney, followed by the liver, but also in the uterus, retroperitoneum, lung, colon, vagina, spermatic cord, bladder, bone, and other tissues and organs. Classic AML: thick-walled vessels lacking elastic fibers; spindle and epithelioid smooth muscle cells; mature adipose tissue. AML is derived from perivascular epithelioid cells (PEC), which are cells that surround the lumen of blood vessels. Current advances: 1, AML belongs to the PEComa family is a true tumor. 2, Some AML and epithelioid AML (EAML) are easily confused clinically and pathologically, and are easily misdiagnosed. 3. AML (partly) is characterized by familial heredity. Renal AML and classification Renal AML accounts for 2.0%~6.4% of renal tumors, with incidence rate of 0.07%~0.3%, male to female ratio of 1:9~4:11, mostly seen in middle-aged women. Renal AML exhibits benign biological behavior, while renal AML with epithelial cell-like changes or renal EAML may exhibit malignant potential or even malignant biological behavior. Renal EAML does not contain fat and abnormal blood vessels, and part of the tumor cytoplasm shows eosinophilia and a large amount of nuclear anomalies and necrosis. Clinicians should not be satisfied with the diagnosis of “renal AML”, but as a specialist, they should classify it as clearly as possible before surgery. 1, familial or sporadic renal AML; 2, diagnosis of atypical renal AML; 3, improve the understanding of the histology and biological behavior of renal EAML. Current opinion: renal EAML is currently considered to be a malignant potential or even malignant potential or even malignant tumor with aggressive biological behavior, and metastasis and recurrence can occur after surgery. Fourth, extra-renal AML associated with the urinary system Its less common and has been reported in the bladder, adrenal gland, prostate, and retroperitoneum. Global Pubmedical search has only about 30 cases, mostly presenting as classical AML, disseminated, located in the perirenal space or retroperitoneal space, seen above, below, and near the renal pelvis and other sites, mostly compressing the kidney but not invasive. The vast majority are not associated with TSC. Retroperitoneal extrarenal AML is more intact than renal AML envelope and has a higher rate of rupture and bleeding. Therefore, it should be treated surgically. V. Treatment of AML The causes of renal AML bleeding include Wunderlichs syndrome (spontaneous non-traumatic bleeding from the kidney), traumatic and tumor hormone-related rapid growth during pregnancy, with an incidence of 0.3-3.0%. For bilateral and multifocal renal AML, selective DSA or preserved renal unit surgery can be used, and extraperitoneal extra-renal AML and EMAL should be treated surgically as soon as possible.