Bone sarcomas: Overview of management, with a focus on surgical treatment considerations
ABSTRACT
Outcomes for patients with bone sarcomas have improved dramatically over the past 40 years, and most bone sarcomas today are treated with surgery and chemotherapy. The most common clinical findings in patients with bone sarcomas are pain and an enlarging bone mass, although pain is not generally a good indicator of malignancy. In general, any patient with a bone mass with indeterminate imaging findings should be referred to an orthopedic oncologist. Bone sarcomas are diagnosed after a biopsy, which is best performed by the surgeon who will be doing the curative resection. Postresection reconstruction of the affected limb is generally done with an allograft-prosthetic composite or a modular metallic prosthetic joint replacement device. Post-therapy follow-up at frequent and regular intervals is critical to assess for recurrence and lung metastasis.
AMPUTATION
When curative surgery is possible and limb-salvaging resection is unlikely to obtain a negative margin or a functionally viable extremity, amputations are still performed. For example, amputation is recommended in a patient with a high-grade calcaneal (heel bone) sarcoma with a large soft-tissue mass. However, amputation is not the usual approach for most bone sarcomas today and it is not benign in outcome. Notably, phantom limb pain and stump pain have been reported after amputation in the typically sensate tumor patient.
Meticulous hemostasis is necessary in all amputations, and myodesis, or direct suturing of muscle to the distal end of the bone, is important for soft-tissue coverage over the distal stump. In general, a fish-mouth incision is used for the upper extremity and thigh, and a posterior flap is used, when possible, below the knee. However, the choice of technique depends on factors such as the presence or absence of a biopsy incision and the location of tumor soft-tissue mass, so local tissue rearrangement or flaps may need to be used for stable coverage or closure.
For all amputation patients, early involvement of an acute pain specialist reduces the incidence of phantom limb pain.
SURVEILLANCE AND FOLLOW-UP
Post-therapy follow-up of patients with bone sarcomas is critical. Even among patients who receive appropriate surgery with negative margins there is a recurrence rate of approximately 9% (personal communication from Dr. Dempsey Springfield), and previously undetectable metastatic disease may become detectable in the postoperative period. In general, patients are followed at 3-month intervals for the first 2 years, at 6-month intervals for the next 3 years, and at yearly intervals thereafter. Follow-up evaluations must include examination of the the involved extremity and imaging of the chest, with radiography or computed tomography, to assess for metastasis.
Rehabilitation is specific to the site of resection and the reconstruction. In general, range of motion is important around the knee, whereas in patients with resection and reconstruction involving the shoulder, hip, or pelvis, it is more important that the affected muscles be given time to heal (6–12 weeks) before aggressive rehabilitation is begun.
Many patients limp postoperatively, particularly in the initial period, and the degree of limp depends primarily on the amount of muscle and the bony insertion sites that are resected with the tumor. Improvements in function are common over time, even at several years after surgery.
FUTURE DIRECTIONS
Despite the advances in bone sarcoma outcomes in recent decades, sarcomas of the pelvis continue to carry a worse prognosis than those of the extremities and thus represent an opportunity for improvement. Among the improvements hoped for is an ability to accomplish partial pelvic resections—eg, of the wing, ischium, or ramus—without need for reconstruction for these smaller localized tumors. Options include amputation (hemipelvectomy) with loss of leg; internal hemipelvectomy (where the pelvis is resected but the leg is left attached without reconstruction of the defect); or resection of the pelvic/acetabular area but with reconstruction using pelvic allografts/total hip composites or large metallic prostheses.
