The Classic: A System for the Surgical Staging of Musculoskeletal Sarcoma

Abstract

William Fisher Enneking (Fig 1) was born in Madison, WI in May 1926. He earned his BS and MD degrees at the University of Wisconsin in 1946 and 1949, respectively. He served in the US Navy during World War II (1943–1944) and again during the Korean War from 1950 to 1962. His career in orthopaedics started with his residency at the University of Chicago (1952–1955). A year later, he became Chief of Orthopaedics at the University of Mississippi and in 1960, he became Chief of Orthopaedics at the University of Florida in Gainesville. Enneking has published numerous papers on musculoskeletal oncology including this classic article, which defines a system for surgical staging of musculoskeletal sarcomas. He was the first President of the Musculoskeletal Tumor Society and is the recipient of numerous honors awarded for his research and teaching. In 1963, Enneking was President of the Orthopaedic Research Society; in 1980, he was President of the American Board of Orthopaedic Surgery; and in 1984, he was President of the American Orthopaedic Association.Fig 1: Dr. William Fisher EnnekingHistorically, an adequate surgical procedure has been the most effective means of treating the majority of primary musculoskeletal sarcomas, and amputation has figured prominently in the surgical armamentarium. 4,7,9,19,21,29,41 The recent evidence that certain chemotherapeutic agents may have significant anti-sarcoma activity 2,15,17,38 and coincident technical advances in irradiation therapy, radiographic localization, and reconstructive surgery have fostered enthusiastic interest in extremity-saving treatments. Almost all such treatments emphasize limb salvage as an alternative to amputation and are usually performed under a protective cloak of adjunctive chemotherapy, irradiation or immunoactive agents. 20,23,24,30,37,39 Since neither chemotherapy nor irradiation therapy alone has been shown to assure long-term local control of bulk disease, surgical intervention remains an essential step in the overall management of musculoskeletal sarcomas. 3,9,17,18,29 Questions concerning the magnitude and timing of the surgical procedure are as unanswered as those relating to the most appropriate use of the adjuncts themselves. Increasingly, the surgeon and his patient are confronted with a bewildering array of therapeutic options, the long-term outcomes of which are unknown. These relatively rare sarcomas increasingly are distributed among a variety of treatment protocols in which multiple parameters differ. This trend necessitates interinstitutional cooperation if sufficient numbers of patients are to be available for the timely evaluation of treatments in clinical use. Such cooperation and even effective interinstitutional communication are seriously hampered by the lack of uniform language, so that meaningful comparison of treatments is currently impossible. Prime factors include the lack of a consistent definition of the surgery performed and a serviceable surgical staging system encompassing bone and soft tissue. Standard terminology will assure that like and unlike treatments are appropriately compared. Although an effective staging system should serve all members of the multidisciplinary team, the biologic behavior of musculoskeletal sarcomas suggests that the most useful staging system will articulate with the surgical procedure. SURGICAL STAGING A surgical staging system for sarcoma should: Incorporate the most significant prognostic factors into a system which describes progressive degrees of risk to which a patient is subject. Delineate progressive stages of disease that have specific implications for surgical management. Provide guidelines to the use of adjunctive therapies. Since its organization in 1959, the American Joint Committee for Cancer Staging and End Results Reporting (AJC) has undertaken responsibility for developing clinically useful staging systems for many kinds of cancer. The intent of staging is to designate “the state of a cancer at various points in time and is related to the natural course of this particular type of cancer.” The purpose is to: “provide a way by which this information can be readily communicated to others; to assist in decisions regarding treatment; and to be a factor in judgement as to prognosis. Ultimately, it provides a mechanism for comparing like or unlike groups of cases, particularly in regard to the results of different therapeutic procedures.” The AJC philosophy expresses the idea that “for most types of cancer, the extent to which the disease has spread is probably the most important factor determining prognosis and must be given prime consideration in evaluating and comparing different therapeutic regimens.” To this end, the TNM system, where T designates the local extent of disease (often translated into size) of the primary tumor, N designates nodal extent, and M, metastatic extent, has been consistently used. 22,31 In addition to anatomic extent, the histopathologic analysis an