A long-term survivor of advanced retroperitoneal dedifferentiated liposarcoma: a successful multimodal approach with extended resection and chemotherapy.

Surgical resection is the mainstay of treatment for retroperitoneal liposarcoma (RPLS). Herein, we describe a case of dedifferentiated RPLS successfully treated with an extended surgical approach with adjuvant chemotherapy. A 61-year-old male was referred to our hospital with a chief complaint of chest tightness. Abdominal computed tomography revealed a large retroperitoneal tumor, 11 cm in diameter, extensively invading the surrounding organs: the celiac axis, the splenic artery, the pancreatic body and tail, the lesser curvature of the stomach and the left adrenal gland. Endoscopic ultrasound-guided fine-needle aspiration biopsy confirmed dedifferentiated liposarcoma, suggesting aggressive tumor biology. We performed total gastrectomy combined with distal pancreatectomy with celiac axis and left adrenal gland resection with a curative intent. The postoperative course was almost uneventful. As the pathological findings indicated a positive margin with a well-differentiated liposarcoma component, we added adjuvant chemotherapy with four cycles of doxorubicin and ifosfamide (AI). Five years after primary surgery, regular follow-up CT demonstrated a pulmonary hilar lymph node enlargement and a tumor at paraesophageal locations. After downsizing chemotherapy with eribulin followed by pazopanib, he underwent partial esophagectomy with dissection of the paraesophageal tumor. The pathological findings indicated recurrence of dedifferentiated liposarcoma with a tumor-free surgical margin. He is currently alive without any evidence of recurrence almost 7 years after the first surgery and 15 months after the second surgery. The long-term survival gained in this patient indicates that extended resections and adjuvant chemotherapy could prolong survival in patients even with RPLS with dedifferentiated tumor histology.