Therapeutic experience with primary liposarcoma from the sigmoid mesocolon accompanied with well-differentiated liposarcomas in the pelvis.

Multifocal liposarcoma with different histological types is rare, especially that originating from the mesentery. We herein report a case of primary myxoid liposarcoma from the sigmoid mesocolon that was accompanied with well-differentiated liposarcomas in the pelvis. The location, the fat signal and the relationship with adjacent organs of the liposarcomas were well shown in the axial, coronal and sagittal dimensions of MRI, giving a comprehensive and specific image before surgery. To alleviate the patient's symptoms and mental stress, a laparotomy was performed. The tumors were all completely excised with macroscopic free margins. The final histopathological report showed that the tumor in the sigmoid mesocolon was a pure myxoid liposarcoma, while the pelvic tumors were spindle cell liposarcomas, a special type of well-differentiated liposarcoma. According to the AJCC staging system, they were all stage IIB. No further adjuvant therapy was performed. Close follow-up after the surgery has been performed, and the patient has remained healthy without any evidence of recurrence or metastasis for 17 months after the surgery.