A 5-year-old girl presented with a big painless mass, sized 24 × 37 × 35 cm, in her lower left limb. MRI revealed a huge heterogeneous mass splaying from the left distal femur to the calcaneal region without bony erosion but compressing the arteries and causing bowing of the left tibia and fibula bones. The difficulty was to determine the best course of action taken which would either be limb salvation or amputation. Considering that only a few muscles could be saved, the author initially recommended amputation but still considered a limb-sparing procedure. After a double set-up examination in the operating room, the author ultimately decided to save the affected limb. The salvaged limb was found to be viable after the surgery, and there was no further recurrence over a subsequent 6-month follow-up period. The careful surgical decision is vital in giving the best possible care to the patient.