Introduction: 3D metal printing is increasingly applied in reconstructive surgery, especially for sarcoma treatment. This case report presents the manufacturing process and outcomes of pelvis reconstruction using a 3D printed hemipelvis prosthesis by in-hospital facilities in conjunction with proximal femoral megaprosthesis replacement.

Case presentation: A 73-year-old male patient was diagnosed with myxoid sarcoma of the right proximal femur and right acetabulum, which required a combined surgical approach: hemipelvis reconstruction with a 3D-printed prosthesis and proximal femur replacement using a megaprosthesis. The hemipelvis prosthesis was designed, tested, and implanted within 2 weeks. Postoperative CT confirmed the perfect fit of the 3D printed prosthesis to the pelvis. The patient could walk with crutches pain-free after 10 days. At 3 months, the functional outcome was evaluated with a Musculoskeletal Tumor Society score (MSTS) of 21 (70%) points and a Harris Hip Score (HHS) of 78.8%.

Clinical discussion: For severe cases of pelvic sarcoma, choosing the commercially available proximal femoral megaprosthesis reduces time compared to manufacturing a 3D-printed module. The hemipelvis prosthesis, designed to fit the femoral part, effectively mimics patient anatomy and promotes osseointegration through lattice structures.

Conclusion: This is the first reported case of pelvic sarcoma resection using a combination of proximal femoral megaprosthesis and custom hemipelvis prosthesis. The approach offers speed, cost-effectiveness, and facilitates rapid functional recovery.