Recently, the surgical team of Professor Gong Kan from the Department of Urology of Peking University Hospital, in close cooperation with multiple departments including general surgery, interventional vascular surgery and anesthesiology, successfully removed a rare giant retroperitoneal tumor and successfully preserved the affected kidney. The patient had hidden pain in the right abdomen 6 months ago, and after examination in other hospitals, a huge retroperitoneal tumor with a diameter of 34 cm was found, reaching down to the iliac fossa and up to the diaphragm, and adhering closely to the liver, renal artery and vena cava, and squeezing and deforming the vena cava and pushing it to the left side. The patient was recommended to Peking University Hospital for consultation and admission. Dr. Wang Chao of the Department of Interventional Vascular Surgery asked Professor Gong Kan of the Department of Urology to consult with him and judged that it was a huge mass in the right kidney with a high possibility of vascular smooth muscle lipoma. As the tumor had benign possibility, it would be better to preserve the affected kidney. However, since the tumor is rich in blood supply, it is extremely difficult to remove the mass and preserve the kidney, and the risk of rupture of the vena cava and renal artery and hemorrhage during surgery is extremely high. After the fourth embolization, the patient was transferred to the Department of Urology. Prof. Zhou Liqun, Prof. He Zhisong and Prof. Yang Yinmo of the Department of General Surgery jointly consulted and instructed to remove the tumor while striving to preserve the affected kidney, and communicated with the Department of Anesthesiology, the Department of Blood Transfusion and other related departments to make adequate preoperative preparations. The whole operation progressed gradually in a tense and smooth manner. The surgical team of Prof. Gong Kan of Urology Department first carefully peeled off the adherent colon and duodenum around the tumor, then after freeing the renal artery and vein and the boundary between the tumor and normal kidney tissue, they quickly performed partial nephrectomy to separate the tumor from the normal kidney tissue, protect the kidney and make room for the operation. Professor Yang Yinmo of general surgery assisted in opening the triangular ligament, lifting the liver, freeing the top of the tumor that was on top of the diaphragm, then carefully and gently freeing the part of the tumor that was closely attached to the vena cava, quickly blocking the blood supply to the tumor, and suturing the vena cava. During this process, Dr. Zeng Yuan of the Department of Anesthesiology cooperated fully to ensure that the patient’s vital signs were stable during the operation. After more than 3 hours of intense surgery, the huge tumor was completely removed with only about 500 ml of bleeding. Giant retroperitoneal tumor is usually closely related to intestine, liver, pancreas and cardiovascular system, which makes the operation more difficult. With the division of medical specialties becoming more and more detailed, multi-disciplinary cooperation is the general trend and can also provide better treatment for patients. The Department of Urology has always attached great importance to multidisciplinary cooperation. In recent years, the surgical teams of Prof. Zhou Liqun, Prof. He Zhisong and Prof. Gong Kan have repeatedly cooperated with sister departments such as general surgery and cardiac surgery respectively, and successfully completed many cases of rare retroperitoneal giant tumor resection. In addition, there are many elderly patients with complex medical diseases that many hospitals are discouraged from. With the full cooperation of multiple departments such as intervention, anesthesia, monitoring and internal medicine, patients have found hope for salvation in PKUH. In recent years, the strong cooperation between various departments of Peking University Hospital, the Department of Urology has successfully completed a number of cases of rare, difficult and complex high-risk surgery Post-operative summary review: a difficult and complex surgery condenses the operator’s countless efforts and sweat, each of these difficult and complex surgery has to be repeatedly and carefully prepared, in addition to surgical planning, the preparation of emergency treatment of various complications, but also psychological preparation, is it pressure? It is also a challenge? It is also a challenge. The night before the surgery, it was often difficult to sleep well, and various scenarios, plans and treatment methods appeared in my mind repeatedly. It was as if he was back in his student days, experiencing a big test, although after a successful surgery there was a kind of look around, hesitant, butcher’s euphoria, but a nameless feeling of exhaustion soon came, but also to persist.