To investigate the feasibility and peri-operative complications of preoperative hypo-fractionated radiotherapy combined with immunotherapy followed by surgery for retroperitoneal sarcoma
Diagnosis & Indication: Primary or recurrent abdominopelvic soft tissue sarcoma. Patients are deemed to have a high probability of R1/R2 resection with upfront surgery and are confirmed to require radiotherapy following Multidisciplinary Team (MDT) discussion.
Target Volume: In cases of multifocal disease, all lesions must be safely encompassable within a single radiotherapy target volume.
Age: Age ≥ 18 years.
Performance Status: Eastern Cooperative Oncology Group (ECOG) performance status 0-2; American Society of Anesthesiologists (ASA) score ≤ 2; patients must be expected to tolerate surgery and radiotherapy.
Significant Comorbidities: Patients with the following concurrent conditions: active hemorrhage, ulceration, intestinal perforation, intestinal obstruction, uncontrolled hypertension, cardiac insufficiency (NYHA Class III-IV), severe hepatic or renal dysfunction (Grade 4), mesenteric ischemia, or severe inflammatory bowel disease (IBD).
Excluded Histologies: Other pathological types, including Gastrointestinal Stromal Tumor (GIST), sarcomatoid carcinoma, sarcomas primarily treated with chemotherapy (e.g., rhabdomyosarcoma and PNET), desmoid fibromatosis, and benign tumors.
Unresectability: Tumor invasion into critical structures such as the liver, pancreatic head, or abdominal aorta, rendering the tumor deemed unresectable.
Prior Radiotherapy: History of prior radiotherapy to the same anatomical region.