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Tumours of the musculoskeletal system
Tumours of the Musculoskeletal System
William
F. Enneking
Over the past 15 years there has been an enthusiastic, almost uninhibited proliferation of limb salvaging (LS) procedures for the management of musculoskeletal sarcomas. Limb salvaging resection is not new. In 1870 it was condemned by Samuel Gross because of almost universal local recurrence and subsequent metastasis. Amputation was advocated despite the then operative mortality of 30%. Resection was only reluctantly performed until the 1930s when it was recognised that certain low grade variants (e.g., secondary chondrosarcoma, parosteal osteosarcoma) could be safely managed in this fashion. In the late 1960s with the advent ofpost-operative chemotherapy and radiation therapy, limb salvage was cautiously embarked upon for classic high grade sarcomas. A surgical staging system for sarcomas was developed, and with it definitions of surgical margins (intracapsular. marginal, wide, and radical) that made it possible to begin assembling data on which to base surgical decisions. By the middle of the 1970s it became apparent that wide surgical margins were required for stage I-A (low grade intra-compartmental) lesions and that they could usually be achieved by LS; stage I-B (low grade, extra-compartmental) lesions also could be controlled by wide margins but amputation was often needed to achieve them; stage 11-A (high grade, intra-compartmental) lesions required radical margins for local control that could often be obtained by LS; and that the commonest stage. II-B (high grade, extra-compartmental) commonly required disarticulation to achieve the required radical margin. By the time of the first international Symposium on _____
___~
William F. Enneking MD, Department of Orthopaedics, College of Medicine. University of Florida, Box J-2446 JHM Health Center. Gainesville, Florida 32610. LJSA
Limb Salvage (Rochester, 1981) 522 LS procedures were reported with an 18,,, ‘/ local recurrence rate and a 15:; incidence of later amputation for reconstructive failures. At the next Symposium (Vienna, 1983) there were 643 LS procedures, an 1 I?); recurrence rate, and a lOti incidence of reconstructive failure. By the third Symposium (Orlando, 1985) the number of LS had risen to 1309 and the recurrence and reconstructive failures had fallen to 71?/ and .5”/,. At the fourth Symposium (Kyoto, 1987) the combined failure rate remained at lo’?/,. During this same period of time the survival rate for high grade stage II sarcomas rose from the historic 10-200/d figure to 50-70”, for both bone and soft tissue sarcomas. The data at the Kyoto Symposium showed that LS, in terms of survival rate, if properly selected, caused no greater risk of metastasis and death than amputation, but that in those instances in which LS resulted in local recurrence there was a significantly greater risk of metastasis and death. Reflecting on these experiences over the past 2 decades it appears that to be rational LS should be based upon accurate staging to ensure an oncologically sound surgical procedure, an orthopaedically sound reconstructive procedure, and, most importantly, be customised to the individual patient. Clearly the development of the surgical staging system has allowed establishment of a rudimentary sense of order for a motley collection of rare tumours to be established. It equally clearly needs refinement to incorporate the emerging significant prognostic variables (biochemical markers, flow cytometry, genetic and immunological parameters) into surgical treatment planning. The steady reduction in local recurrences after LS is attributable to a number of factors: rapid development of sophisticated radiographic imaging techniques has enabled much greater accuracy in both pre___ ~~__. -
134
TUMOURS
OF THE
MUSCULOSKELETAL
SYSTEM
operative staging and surgical planning, new developments in pathologic techniques and methodology has led to greater diagnostic accuracy while minimising the amount of tissue contamination, and establishment of treatment teams in oncologic centres has fostered the development of surgical expertise in both oncologic and reconstructive surgery. It is abundantly clear that the establishment of referral centres, in which by pooling large numbers of these uncommon tumours, expertise in radiology, pathology, oncology and surgery has been developed, has played a dominant role in the development of low-risk limb salvaging techniques. The continual rise in survival rates are attributable in some measure to the improvements in local control rates, but primarily to the advances in adjuvant radiation and chemotherapy. While the use of postoperative chemotherapy has made substantial improvement in survival rates for osteosarcoma, Ewings sarcoma, rhabdomyosarcoma, and various lymphosarcomas-its efficacy remains in doubt in many of the soft tissue sarcomas, and it appears to be ineffective in lesions such as chondrosarcoma and chondroma. The marked increase in the proportion of patients who are low-risk candidates for LS is attributable primarily to advances in pre-operative radiation and or chemotherapy. Approximately two-thirds of patients presenting with stage II-B lesions, who 10 years ago would have been considered only for amputation, are good responders to neoadjuvant therapy and become low risk candidates for wide LS procedures. It remains to be seen whether even more conservative marginal surgery can be made low-risk by such management. The early high failure rate of reconstruction was often due to selection of inappropriate procedures, under the assumption that orthopaedically unsound procedures were justified in view of a limited prognosis, compounded by the side effects of adjuvant therapy. The situation was further complicated by unrealistic expectations on the part of the patients and unrealistic
enthusiasm on the part of their surgeons. With advances in internal fixation, microvascular surgery, allografting, prosthetic fabrication and surgical experience the incidence of reconstructive failures is rapidly decreasing and the functional results are correspondingly improving. However, with many of these lesions arising in childhood, and with ever increasing life-spans, reconstructive technology and expertise is being seriously challenged. Caution must be taken not to compromise the oncologic principles so dearly learned in order to further the reconstructive efforts. In particular high-tech innovations such as ‘growing’ prostheses in childhood or total joint allografts must be firmly rooted in scientific evidence rather than prematurely applied for their emotional appeal. Finally, the issue of individualisation to the patient cannot be over emphasised. Conventional amputation may often provide a more comfortable, unrestricted, active life-style than a fragile reconstruction after a marginal resection fraught with complications from the side effects of life-saving adjuvant therapy. Studies from both the National Cancer Institute and the Roswell Park Institute have failed to substantiate the hypothesis that the quality of life is substantially better in those patients treated by LS rather than amputation. Advances in modifications of conventional amputation, particularly rotation plasty, and in prosthetic limbs, in selected instances make amputation a more satisfactory procedure. It is quite apparent that a 13year-old adolescent with a stage II-B osteosarcoma of the distal tibia will enjoy a less restrictive life-style with a below-knee amputation and a patellar-tendon bearing prosthetic limb than with a fragile ankle arthrodesis or prosthesis in face of the need for postoperative adjuvant chemotherapy. In summary, the past 2 decades have seen remarkable progress in the management of musculoskeletal tumours by limb salvaging procedures. The current results indicate how much work remains to be done in this interesting, challenging, and rewarding field.
William
F. Enneking
Over the past 15 years there has been an enthusiastic, almost uninhibited proliferation of limb salvaging (LS) procedures for the management of musculoskeletal sarcomas. Limb salvaging resection is not new. In 1870 it was condemned by Samuel Gross because of almost universal local recurrence and subsequent metastasis. Amputation was advocated despite the then operative mortality of 30%. Resection was only reluctantly performed until the 1930s when it was recognised that certain low grade variants (e.g., secondary chondrosarcoma, parosteal osteosarcoma) could be safely managed in this fashion. In the late 1960s with the advent ofpost-operative chemotherapy and radiation therapy, limb salvage was cautiously embarked upon for classic high grade sarcomas. A surgical staging system for sarcomas was developed, and with it definitions of surgical margins (intracapsular. marginal, wide, and radical) that made it possible to begin assembling data on which to base surgical decisions. By the middle of the 1970s it became apparent that wide surgical margins were required for stage I-A (low grade intra-compartmental) lesions and that they could usually be achieved by LS; stage I-B (low grade, extra-compartmental) lesions also could be controlled by wide margins but amputation was often needed to achieve them; stage 11-A (high grade, intra-compartmental) lesions required radical margins for local control that could often be obtained by LS; and that the commonest stage. II-B (high grade, extra-compartmental) commonly required disarticulation to achieve the required radical margin. By the time of the first international Symposium on _____
___~
William F. Enneking MD, Department of Orthopaedics, College of Medicine. University of Florida, Box J-2446 JHM Health Center. Gainesville, Florida 32610. LJSA
Limb Salvage (Rochester, 1981) 522 LS procedures were reported with an 18,,, ‘/ local recurrence rate and a 15:; incidence of later amputation for reconstructive failures. At the next Symposium (Vienna, 1983) there were 643 LS procedures, an 1 I?); recurrence rate, and a lOti incidence of reconstructive failure. By the third Symposium (Orlando, 1985) the number of LS had risen to 1309 and the recurrence and reconstructive failures had fallen to 71?/ and .5”/,. At the fourth Symposium (Kyoto, 1987) the combined failure rate remained at lo’?/,. During this same period of time the survival rate for high grade stage II sarcomas rose from the historic 10-200/d figure to 50-70”, for both bone and soft tissue sarcomas. The data at the Kyoto Symposium showed that LS, in terms of survival rate, if properly selected, caused no greater risk of metastasis and death than amputation, but that in those instances in which LS resulted in local recurrence there was a significantly greater risk of metastasis and death. Reflecting on these experiences over the past 2 decades it appears that to be rational LS should be based upon accurate staging to ensure an oncologically sound surgical procedure, an orthopaedically sound reconstructive procedure, and, most importantly, be customised to the individual patient. Clearly the development of the surgical staging system has allowed establishment of a rudimentary sense of order for a motley collection of rare tumours to be established. It equally clearly needs refinement to incorporate the emerging significant prognostic variables (biochemical markers, flow cytometry, genetic and immunological parameters) into surgical treatment planning. The steady reduction in local recurrences after LS is attributable to a number of factors: rapid development of sophisticated radiographic imaging techniques has enabled much greater accuracy in both pre___ ~~__. -
134
TUMOURS
OF THE
MUSCULOSKELETAL
SYSTEM
operative staging and surgical planning, new developments in pathologic techniques and methodology has led to greater diagnostic accuracy while minimising the amount of tissue contamination, and establishment of treatment teams in oncologic centres has fostered the development of surgical expertise in both oncologic and reconstructive surgery. It is abundantly clear that the establishment of referral centres, in which by pooling large numbers of these uncommon tumours, expertise in radiology, pathology, oncology and surgery has been developed, has played a dominant role in the development of low-risk limb salvaging techniques. The continual rise in survival rates are attributable in some measure to the improvements in local control rates, but primarily to the advances in adjuvant radiation and chemotherapy. While the use of postoperative chemotherapy has made substantial improvement in survival rates for osteosarcoma, Ewings sarcoma, rhabdomyosarcoma, and various lymphosarcomas-its efficacy remains in doubt in many of the soft tissue sarcomas, and it appears to be ineffective in lesions such as chondrosarcoma and chondroma. The marked increase in the proportion of patients who are low-risk candidates for LS is attributable primarily to advances in pre-operative radiation and or chemotherapy. Approximately two-thirds of patients presenting with stage II-B lesions, who 10 years ago would have been considered only for amputation, are good responders to neoadjuvant therapy and become low risk candidates for wide LS procedures. It remains to be seen whether even more conservative marginal surgery can be made low-risk by such management. The early high failure rate of reconstruction was often due to selection of inappropriate procedures, under the assumption that orthopaedically unsound procedures were justified in view of a limited prognosis, compounded by the side effects of adjuvant therapy. The situation was further complicated by unrealistic expectations on the part of the patients and unrealistic
enthusiasm on the part of their surgeons. With advances in internal fixation, microvascular surgery, allografting, prosthetic fabrication and surgical experience the incidence of reconstructive failures is rapidly decreasing and the functional results are correspondingly improving. However, with many of these lesions arising in childhood, and with ever increasing life-spans, reconstructive technology and expertise is being seriously challenged. Caution must be taken not to compromise the oncologic principles so dearly learned in order to further the reconstructive efforts. In particular high-tech innovations such as ‘growing’ prostheses in childhood or total joint allografts must be firmly rooted in scientific evidence rather than prematurely applied for their emotional appeal. Finally, the issue of individualisation to the patient cannot be over emphasised. Conventional amputation may often provide a more comfortable, unrestricted, active life-style than a fragile reconstruction after a marginal resection fraught with complications from the side effects of life-saving adjuvant therapy. Studies from both the National Cancer Institute and the Roswell Park Institute have failed to substantiate the hypothesis that the quality of life is substantially better in those patients treated by LS rather than amputation. Advances in modifications of conventional amputation, particularly rotation plasty, and in prosthetic limbs, in selected instances make amputation a more satisfactory procedure. It is quite apparent that a 13year-old adolescent with a stage II-B osteosarcoma of the distal tibia will enjoy a less restrictive life-style with a below-knee amputation and a patellar-tendon bearing prosthetic limb than with a fragile ankle arthrodesis or prosthesis in face of the need for postoperative adjuvant chemotherapy. In summary, the past 2 decades have seen remarkable progress in the management of musculoskeletal tumours by limb salvaging procedures. The current results indicate how much work remains to be done in this interesting, challenging, and rewarding field.