Peritoneal resident macrophages in tumor metastasis and immunotherapy.

BACKGROUND We report a case of a giant (55×35×27 cm, 26 kg) retroperitoneal liposarcoma (RPLS) to provide surgical insights for managing such complex tumors. Due to the potential space in the retroperitoneal cavity, primary retroperitoneal liposarcoma can grow to very large sizes without causing typical symptoms, frequently encasing critical vessels and organs and making resection highly challenging. Most chemotherapy drugs have limited effectiveness against RPLS, while radiotherapy dosages are significantly constrained by toxicity concerns. These limitations underscore why complete surgical resection (R0) continues to be the cornerstone of RPLS treatment and the single most important prognostic factor. While R0 resection remains the primary treatment, innovative approaches are needed to improve outcomes. CASE REPORT A 59-year-old man came for medical treatment due to the continuous growth of an abdominal mass for 2 years. Imaging revealed tumor encasement of the left renal vessels and descending colon, with compression of the aorta and inferior vena cava. Following multidisciplinary evaluation, vascular-oriented resection (VOR) combined with total retroperitoneal lipectomy (TRL) was performed, achieving complete tumor removal along with the involved left kidney and partial colon. Pathology confirmed dedifferentiated liposarcoma (MDM2/CDK4+, Ki-67 10-30%). Postoperatively, the patient showed significant improvement, with resolved lower-limb edema and dyspnea. CONCLUSIONS This case demonstrates the feasibility of VOR combined with TRL for giant retroperitoneal liposarcoma, highlighting the importance of preoperative 3D vascular reconstruction and multidisciplinary collaboration. Although surgical techniques have advanced, the 5-year recurrence rate remains unacceptably high at nearly 50%, highlighting the urgent need to explore more effective adjuvant therapies.