An oncologic emergency case of massive dedifferentiated liposarcoma of the small bowel mesentery.

We report the case of a 71-year-old man who complained of abdominal distension, pedal edema, respiratory discomfort, and weight gain. Computed tomography revealed a giant, poorly enhancing tumor occupying the entire abdomen, with abdominal ascites. The tumor was causing hydronephrosis, compression of the inferior vena cava, and elevation of the diaphragm. The patient exhibited deterioration of performance status (PS3 on the ECOG scale) and required oxygen; therefore, emergency surgery was performed. Operative findings included bloody abdominal ascites and peritoneal dissemination. The large tumor arose from the small bowel mesentery, and infiltrated into the cecum and sigmoid colon. Tumor excision with ileocecal resection and sigmoidectomy was performed. Histopathological examination revealed dedifferentiated liposarcoma. The patient was discharged on postoperative day 22, but pre-discharge CT revealed a recurrent liposarcoma in the retroperitoneum. Therefore, chemotherapy was initiated and the treatment has been continued for over 6 months after surgery. Due to the rarity of this disease, there is no consensus regarding treatment strategies for DDLPS with peritoneal dissemination or in patients with a poor general condition, especially in the setting of oncologic emergency. In this case, multimodal treatment was used to successfully manage this life-threatening state and obtain satisfactory therapeutic results.