Background: Combined limb-sparing surgery and radiation therapy are considered the standard of care for higher grade soft tissue sarcomas (STS) of the extremities. The risk of post-radiation fracture after this treatment modality is well known, but still underestimated, and can end in serious long-term secondary problems years later.
Methods: We reviewed the records of three patients (two female and one male) with pathological femur fractures years after wide local excision of an STS of the proximal lower extremity and postoperative radiation therapy. All patients received more than 50 gray (Gy) to the entire femur circumference; chemotherapy was not given. During surgery, all patients had bone exposure, and in two patients with stripping of the periosteum.
Results: The median time from surgery to fracture was 116 months (range from 84 to 156 months). The median age at the time of diagnosis was 66 years old (range, 54 to 79 years old). All fractures were located at the site of the radiation treatment field. Two fractures occurred after minimal or no trauma, one fracture after a mountain bike fall. Despite standard operative fracture treatment, all three patients developed a non-union. One patient later died due to uncontrolled pulmonary metastasis and local recurrent disease independent from the femoral non-union. In the second case, an exarticulation at hip level due to an uncontrolled infected non-union had to be performed after several surgical revisions with remaining soft tissue defects. The third patient finally achieved fracture union after two years of treatment.
Conclusions: The risk of pathological fractures at the former treatment site is high, even years later. The rate of non-unions after a difficult fracture treatment in this particular clinical situation seems to be very high and may be associated with severe complications, ending in a significant impairment of the quality of life and physical disability.