Treatment

Diagnosis

The route to osteosarcoma diagnosis usually begins with an x-ray, continues with a combination of scans (CT scan, PET scan (Positron emission tomography), bone scan, MRI) and ends with a surgical biopsy. Films are suggestive, but bone biopsy is the only definitive method to determine whether a tumor is malignant or benign.

There are two main types of biopsy: a needle aspiration and a surgical biopsy. The location, incision and technical aspects of the biopsy can affect a patient’s treatment options and outcome.

Treatment usually starts after a biopsy of the tumor.

Osteosarcoma is often treated with a combination of therapies that can include surgery, chemotherapy and radiation therapy.

Current standard treatment is to use neo-adjuvant chemotherapy (chemotherapy given before surgery) followed by surgical resection.

Surgery is used after chemotherapy to remove any remaining tumor. In most cases, surgery can remove the tumor while saving the affected limb. This is called limb-salvage surgery. In rare cases, more involved surgery (such as amputation) is necessary.

Though radiation therapy is not widely used in osteosarcoma treatment, it can be effective and is occasionally recommended, especially when a tumor is difficult to remove surgically or when residual tumor cells remain after surgery.

Types of Surgery

Surgery for osteosarcoma involves biopsy, surgical removal of the tumor, bone grafts, limb salvage procedures, amputation, and/or reconstruction. The type of surgery will depend on the size and location of the tumor, and whether the cancer has spread.

¤ Limb-salvage surgery: it is sometime necessary to remove all or part of a limb. In most cases, however, limb-salvage surgery is used to avoid amputation. Through limb-salvage surgery, all of the bone and cartilage involved with the tumor, including some degree of muscle surrounding it, is removed, while nearby tendons, nerves and vessels are saved. The bone that is removed is replaced with a bone graft or with a metal prosthesis (Image 9.13).

Image 9.13 Prosthesis replacing.

Subsequent surgery may be needed to repair or replace the reconstruction which can become loose or break.

Patients who have undergone limb-salvage surgery need intensive rehabilitation. It may take as long as a year for a patient to regain full use of a limb following limb-salvage surgery. Rarely, some patients who have this operation may eventually have to undergo amputation.

¤ Amputation:in some cases, if the tumor cannot be removed because, for example, it involves the nerves and blood vessels, amputation is the only option.

The advantages of an amputation are that it is a simple operation with minimal chances of surgical complication and it definitively removes the local tumor. The functional outcome is good with the modern prostheses available today.

¤ Rotationplasty:occasionally, because of a tumor’s size or location, an amputation or rotationplasty is the best way to completely remove the cancer and restore the patient to a functional life.

This operation preserves the lower leg and uses the ankle as a knee joint (Image 9.14). In this procedure, the patient functions more like a below knee amputee rather than an above knee amputee. It is especially useful in very young children where limb length would be an issue.

Image 9.14 Rotationplasty