Teams Work to Save Life and Limb
Donald A. Hackbarth, MD
Medical College of Wisconsin Orthopedic Oncologist
When cancer attacks bone or muscle, physicians in several specialties work together to defeat the disease and save the patient's limb. Donald Hackbarth, MD, explains the varieties of orthopedic cancer and talks about the multi-disciplinary approach to treating them.
Q. As a musculoskeletal oncologist, what kinds of cancers do you deal with?
When you think of musculoskeletal oncology, you think of physicians and surgeons who treat primary tumors – those that begin in bone, muscle, or connective tissues. The other hat we wear is treating patients who have metastatic cancers, that is, cancers that have spread to the bone from other organs. In fact, the most common type of "bone cancer" is a metastatic tumor. That includes cancers of the breast, lung, prostate, kidney, thyroid, and colon.
Q. What types of cancer originate in the bone and muscles?
The most common primary bone cancer in adults is called multiple myeloma. This is a tumor that originates in bone marrow, specifically the plasma cells.
The most common type of bone cancer in children and young adults is called osteosarcoma, a cancer which begins in the osteoblasts or cells that form bone. This cancer is most commonly seen in children and teen-agers. It can affect adults in their early 20's and is occasionally seen in later years. The incidence of this tumor is rare, and we see between 10 and 12 osteosarcomas each year.
Soft tissue tumors can be benign or malignant. The most common soft tissue tumors are benign. These would include tumors such as lipomas (benign, fatty tumors) and cystic tumors.
Malignant soft tissue tumors are called soft tissue sarcomas. These are rare, representing 0.5% of all cancers. Soft tissues include connective tissues, muscles, tendons, blood vessels, and nerves that surround the bones.
Q. What are the symptoms of bone and muscle cancer?
A soft tissue tumor usually begins as a painless, growing mass in the extremity or trunk. As the mass increases in size, it may become painful. The pain may occur with activity, at rest or it may awaken the patient at night. As the soft tissue mass increases in size, it may encroach upon a nerve or a blood vessel causing dysfunction in the patient's arm or leg, such as numbness or tingling, loss of muscle strength, or a limp.
The symptoms of bone tumors can vary. Slow growing benign tumors may have no symptoms. Rapidly growing or aggressive benign tumors and malignant bone tumors usually are associated with a soft tissue mass outside the bone and a dull ache or deep discomfort which also cause pain at rest or at night. These tumors may also be associated with a pathologic fracture of the bone.
Q. What are the treatment options?
The majority of soft tissue sarcomas and bone sarcomas are treated with limb-sparing procedures.
For example, we treat primary bone cancers, such as osteosarcoma, with a combination of chemotherapy and surgery. Chemotherapy diminishes the size of the tumor, and kills any cells which have spread outside the tumor to other organs, such as the lungs. The patient then undergoes surgery to remove the malignancy and affected soft tissues and reconstruct the limb using a prosthetic implant, a donor bone, or a combination of a prosthetic implant and donor tissue.
Treatment of soft tissue sarcomas is, once again, a team effort. Our adult and pediatric oncology colleagues frequently give combinations of chemotherapeutic drugs to the patient. Then, our radiation oncology colleagues deliver radiation therapy to the tumor to shrink it and allow limb salvage surgery. After the soft tissue sarcoma is removed with the surrounding muscles or muscle group, the defect created by this procedure is reconstructed. This can be done with local tissues or by moving muscles from another part of the body, called a free tissue transfer. Free tissue transfers are performed by our microsurgical colleagues. Occasionally, a large blood vessel needs to be resected, and, in that situation, we call upon our vascular surgical colleagues to perform a vascular reconstruction.
Thus, the reconstruction following the resection of the tumor will often require several specialties to care for the patient.