Purpose of the study: Prognosis is generally considered poor for patients with an iliac bone localization of Ewing sarcoma because the deep tumor is often large with initial metastases. This study demonstrates that the predictive value of these factors is related to treatment and that early en bloc resection can modify the prognosis.

Material and method: We have treated 62 cases of Ewing tumor of the iliac bone since 1976, 36 males and 25 females, mean age 16.5 years (range 4 – 47). Thirteen patients presented primary metastases. Mean tumor size, measured by digital imaging, was 729 cm3. Adapted chemotherapy was given in all cases. Local treatment included exclusive radiotherapy in 20 patients, radiochemotherapy in 15 and exclusive en bloc extratumoral resection in 27.

Results: At 15 years mean follow-up, overall relapse-free survival at ten years was 38%. This rate was 43% among patients without metastasis and 18% for those with initial metastasis (the three other patients underwent surgical resection of a primary focus and a bone metastasis). For patients with localized disease, prognosis was essentially determined by type and timing of local treatment. Surgical resection did not appear to have a significant effect on prognosis for patients operated on after three months; for these patients, only those with total histological response survived. Conversely, patient who underwent surgery before three months with en bloc resection and chemotherapy with at least five drugs had a relapse-free survival of 80% at ten years.

Conclusion: The prognosis of Ewing sarcoma is seriously dependent on the therapeutic modality, even when the localization is known to have a poor prognosis such as the iliac bone. Early en bloc extratumoral resection (before three months) greatly improved the prognosis of patients without metastasis, even for those with a very large tumor. Conversely, prognosis remained very poor for patients given exclusive radiotherapy or operated on late.

Purpose: In our records on bone tumours, secondary chondrosarcomas account for slightly less than 15% of all chondrosarcomas (20/150). The presentation is quite variable making diagnosis relatively difficult. We reviewed our experience to evaluate diagnosis, frequency, and prognosis.

Material and methods: From 1981 to January 2002, we had 20 chondrosarcomas which developed on pre-existing lesions: solitary exostoses (n=11), solitary chondroma (n=1), multiple exostosis (n=6), multiple enchondromatosis (n=2). Localisations were: pelvis (n=9), femur (n=3), humerus (n=2), tibia (n=3), spine (n=2), scapula (n=1). Histological classification was: grade I (n=7), grade II (n=9), grade III (n=1), and dedifferentiated sarcoma (n=3). Surgery was performed in all patients, alone for grade I and II chondrosarcoma, in association with chemotherapy (n=3) and radiotherapy (n=1) in three patients with dedifferentiated sarcoma.

Results and prognostic factors: At last follow-up (mean 9 years 10 months), five patients had died after local recurrence (n=3) or metastatic dissemination (n=2). The other fifteen patients were living (mean follow-up 155 months). The main prognostic factor was histological grade of chondrosarcoma. All patients with grade I chondrosarcoma (n=7) survived versus only two-thirds of those with grade II chondrosarcoma and half (2/4) of those with grade III or dedifferentiated chondrosarcoma. The second prognostic factor was initial management. Inadequate care initially led to misdiagnosis or delayed diagnosis (n=4), local recurrence (n=3) and loss of chance of survival (n=3). Grade I chondrosarcoma was occasionally taken for benign exostosis despite a cartilage cuff measuring more than 1 cm, normally a sign of chondrosarcoma.

Conclusion: 1. Because of the severity of secondary dedifferentiated chondrosarcoma, resection should be performed in adults presenting exostosis with a large residual cartilage cuff, particularly in high-risk locations (pelvis). 2. Because of the difficulty in recognising the histological features of grade I chondrosarcoma, the diagnosis of degeneration should be retained in adults if the cartilage cuff exceeds 1 cm. Lesions are suspicious if the cartilage cuff exceeds 5 mm.

A “hands-on” composite gives a similar functional result as a custom-made prosthesis and has a much better function than alternative techniques. Less expensive and more flexible than custom-made prostheses, it can be used even when no part of the iliac wing remains. The use of cement permits the adjunction of antibiotics needed for these complicated cases.

After peri-acetabular resection for bone sarcoma, a reconstructive procedure is necessary to stabilize the hip, avoid limb discrepancy, and permit full weight bearing. This procedure needs to be easy to perform because resection of the area is time and blood consuming. This leads to the use of a “hands-on” composite prosthesis.

Our reconstructive procedure uses a titanium cup with a long screw that is fixed in the remaining bone (sacrum or spine). When the cup is firmly fixed to the bone, the gap between the cup and bone is filled with cement loaded with antibiotics, and the polyethylene component is cemented on the innominate prosthesis. The femoral component of a usual hip total prosthesis is then implanted.

Since 1990 we have used this reconstructive procedure in 50 patients, 27 with bone sarcomas involving the acetabulum (11 chondrosarcomas, 9 Ewing’s sarcomas and 7 other sarcomas) and 23 for metastatic disease. Thirty of these patients were already metastatic when operated. The average duration of the reconstructive procedure was 45 minutes. Walking started from the fourth to tenth day after operation, but full weight bearing was usually authorised after six weeks.

Postoperative complications were frequent. Seven deep infections occurred, four required ablation of the prosthesis, and one would benefit from a saddle prosthesis. 33% of the patients had postoperative dislocation of the hip prosthesis and 13 patients had to be reoperated. Only two loosenings have been observed – one after deep infection and one after local recurrence in the sacral bone. Oncologic results: With a mean follow-up of five years, 28 patients died of disease and one from an unrelated disease. Four others with disease are still living. Seven local recurrences were observed (four in chondrosarcomas with a contaminated resection). The difficulty in obtaining wide margins explains the high rate of local recurrence (14 %). For patients with localised disease, the five-year overall survival rate is 75% and the five-year disease-free survival rate is 60%.

According to the Society for Musculoskeletal Oncology criteria, orthopaedic results were excellent in 7 patients, good in 30, fair in 6, and bad in 6. The mean functional score of 46 patients who still have their prostheses is 83% with usually no pain, excellent acceptance, length discrepancy of less than 1 cm, average flexion of 100 degrees, and unlimited walking without support.

We conclude that the rapidity and flexibility of this procedure are the positive aspects of this reconstructive technique. However, perfect positioning of the prosthesis remains difficult in a very large peri-acetabular resection. A computed guide is of great help to specify safe margins and prosthesis positioning. Longer follow-up is needed to ensure that the rate of late loosening will not be too high.

Nowadays 80% of patients with bone sarcomas can benefit from limb salvage. Their disease-free life expectancy is not jeopardised by conservative surgery as long as safe margins are obtained. For this reason, the oncological result relies on the accuracy of pre-operative and per-operative surgical measurements. Pre-operative evaluation of tumours is now quite accurate with digital margins (computed tomography, MNR, digital angiography). However, surgeons are still using centimeters or conventional radiographs with their own technical limitations for per-operative evaluation. A more accurate technique is needed.

The system is composed of three components: 1) a color, graphic computer workstation with software to calculate and present the location of the surgical instrument on a three-dimensional, reconstructed bone image, 2) a complete set of hand-held instruments containing infrared emitters, 3) an infrared receiver linked to the work station. This measuring system enables determination of the position and incidence of a surgical instrument in real time during surgery, with an accuracy of less than one mm.

The system requires four steps: 1) recording data with C.T., N.M.R. or angiography, 2) creating a three-dimensional image displayed on the computer screen for preoperative simulation of a virtual operation, 3) recording the very important anatomical points of the patient and optimal incidences of the surgical instruments, 4) preoperative location of surgical instruments and control of their location on bone.

This system is very useful for resection of bone tumours when the conventional location is uncertain (innonimate bone, rib), when very sharp accuracy is needed to preserve the growth plate of the distal femur in young children, and to avoid medullary damage in a spinal tumour.

The frameless stereotactic device is also very accurate in the reconstructive phase of limb salvage. After an internal hemipelvectomy, the device permits localisation of the acetabular prosthesis in the precise location before resection.

In our practice, the accuracy of the video guiding system is always within two mm as compared to conventional measurements usually between one or two cm for long bones and three to five cm for innominate bone.

The use of a video guidance system is very beneficial for limb salvage surgery for pelvic bone tumours.

Nowadays 80% of patients with bone sarcomas can benefit from limb salvage. Their disease-free life expectancy is not jeopardised by conservative surgery as long as safe margins are obtained. For this reason, the oncological result relies on the accuracy of pre-operative and per-operative surgical measurements. Pre-operative evaluation of tumours is now quite accurate with digital margins (computed tomography, MNR, digital angiography). However, surgeons are still using centimeters or conventional radiographs with their own technical limitations for per-operative evaluation. A more accurate technique is needed.

The system is composed of three components: 1) a color, graphic computer workstation with software to calculate and present the location of the surgical instrument on a three-dimensional, reconstructed bone image, 2) a complete set of hand-held instruments containing infrared emitters, 3) an infrared receiver linked to the work station. This measuring system enables determination of the position and incidence of a surgical instrument in real time during surgery, with an accuracy of less than one mm.

The system requires four steps: 1) recording data with C.T., N.M.R. or angiography, 2) creating a three-dimensional image displayed on the computer screen for preoperative simulation of a virtual operation, 3) recording the very important anatomical points of the patient and optimal incidences of the surgical instruments, 4) preoperative location of surgical instruments and control of their location on bone.

This system is very useful for resection of bone tumours when the conventional location is uncertain (innonimate bone, rib), when very sharp accuracy is needed to preserve the growth plate of the distal femur in young children, and to avoid medullary damage in a spinal tumour.

The frameless stereotactic device is also very accurate in the reconstructive phase of limb salvage. After an internal hemipelvectomy, the device permits localisation of the acetabular prosthesis in the precise location before resection.

In our practice, the accuracy of the video guiding system is always within two mm as compared to conventional measurements usually between one or two cm for long bones and three to five cm for innominate bone.

The use of a video guidance system is very beneficial for limb salvage surgery for pelvic bone tumours.

The purpose of this study was to investigate the importance of the timing of surgery for disease-free survival (DFS). The increasing efficacy of neo-adjuvant chemotherapy in Ewing’s sarcoma modifies the prognostic factors. In a recent monocentric study the classical prognostic value of size and location of the primary disappeared (Delepine G, Alkallaf S. J. Chem.1997;9:352–63.). This study confirmed the value of histologic response and pointed out the importance of dose intensity of VCR and ACTD. However, the role of local treatment could not be significantly demonstrated because the number of patients was too small.

Seventy-five patients with an average age of 19 years (range 4 to 40) years with Ewing’s sarcoma of bone fulfilled the inclusion criteria for this study: localised tumour at first screening (CT of lungs + bone scan) and location of the tumour in resectional bones (limb, scapula, innominate, rib, maxilla, skull). Metastatic patients and vertebral locations were excluded. The patients received multi-drug chemotherapy and were treated by surgery and radiotherapy in cases of bad responders and/or marginal surgery. The histologic response was evaluated according to Picci’s criteria (Picci, A. J Clin Oncol.1993;11:1793–99). The duration of local treatment was calculated from biopsy to surgery in weeks.

After a mean follow-up of 54 months, 41 patients were in first complete remission. Patients operated before the tenth week had a higher chance (68%) of first complete remission than patients operated later (DFS: 43%). The difference is significant (p< 0.03). Further analysis shows that the difference is due to late local control, which causes a dismal prognosis for bad responders.

Local treatment must be performed early, especially when histologic response is incomplete or uncertain. Preoperative chemotherapy that is too long increases the risk of metastases in bad responders. These factors must be taken into account when analysing multicentre protocols.

The purpose of this study was to investigate the importance of the timing of surgery for disease-free survival (DFS). The increasing efficacy of neo-adjuvant chemotherapy in Ewing’s sarcoma modifies the prognostic factors. In a recent monocentric study the classical prognostic value of size and location of the primary disappeared (Delepine G, Alkallaf S. J. Chem.1997;9:352–63.). This study confirmed the value of histologic response and pointed out the importance of dose intensity of VCR and ACTD. However, the role of local treatment could not be significantly demonstrated because the number of patients was too small.

Seventy-five patients with an average age of 19 years (range 4 to 40) years with Ewing’s sarcoma of bone fulfilled the inclusion criteria for this study: localised tumour at first screening (CT of lungs + bone scan) and location of the tumour in resectional bones (limb, scapula, innominate, rib, maxilla, skull). Metastatic patients and vertebral locations were excluded. The patients received multi-drug chemotherapy and were treated by surgery and radiotherapy in cases of bad responders and/or marginal surgery. The histologic response was evaluated according to Picci’s criteria (Picci, A. J Clin Oncol.1993;11:1793–99). The duration of local treatment was calculated from biopsy to surgery in weeks.

After a mean follow-up of 54 months, 41 patients were in first complete remission. Patients operated before the tenth week had a higher chance (68%) of first complete remission than patients operated later (DFS: 43%). The difference is significant (p< 0.03). Further analysis shows that the difference is due to late local control, which causes a dismal prognosis for bad responders.

Local treatment must be performed early, especially when histologic response is incomplete or uncertain. Preoperative chemotherapy that is too long increases the risk of metastases in bad responders. These factors must be taken into account when analysing multicentre protocols.

A “hands-on” composite gives a similar functional result as a custom-made prosthesis and has a much better function than alternative techniques. Less expensive and more flexible than custom-made prostheses, it can be used even when no part of the iliac wing remains. The use of cement permits the adjunction of antibiotics needed for these complicated cases.

After periacetabular resection for bone sarcoma, a reconstructive procedure is necessary to stabilize the hip, avoid limb discrepancy, and permit full weight bearing. This procedure needs to be easy to perform because resection of the area is time and blood consuming. This leads to the use of a “hands-on” composite prosthesis.

Our reconstructive procedure uses a titanium cup with a long screw that is fixed in the remaining bone (sacrum or spine). When the cup is firmly fixed to the bone, the gap between the cup and bone is filled with cement loaded with antibiotics, and the polyethylene component is cemented on the innominate prosthesis. The femoral component of a usual hip total prosthesis is then implanted.

Since 1990 we have used this reconstructive procedure in 50 patients, 27 with bone sarcomas involving the acetabulum (11 chondrosarcomas, 9 Ewing’s sarcomas and 7 other sarcomas) and 23 for metastatic disease. Thirty of these patients were already metastatic when operated. The average duration of the reconstructive procedure was 45 minutes. Walking started from the fourth to tenth day after operation, but full weight bearing was usually authorised after six weeks.

Postoperative complications were frequent. Seven deep infections occurred, four required ablation of the prosthesis, and one would benefit from a saddle prosthesis. 33% of the patients had postoperative dislocation of the hip prosthesis and 13 patients had to be reoperated. Only two loosenings have been observed – one after deep infection and one after local recurrence in the sacral bone. Oncologic results: With a mean follow-up of five years, 28 patients died of disease and one from an unrelated disease. Four others with disease are still living. Seven local recurrences were observed (four in chondrosarcomas with a contaminated resection). The difficulty in obtaining wide margins explains the high rate of local recurrence (14 %). For patients with localised disease, the five-year overall survival rate is 75% and the five-year disease-free survival rate is 60%.

According to the Society for Musculoskeletal Oncology criteria, orthopaedic results were excellent in 7 patients, good in 30, fair in 6, and bad in 6. The mean functional score of 46 patients who still have their prostheses is 83% with usually no pain, excellent acceptance, length discrepancy of less than 1 cm, average flexion of 100 degrees, and unlimited walking without support.

We conclude that the rapidity and flexibility of this procedure are the positive aspects of this reconstructive technique. However, perfect positioning of the prosthesis remains difficult in a very large periacetabular resection. A computed guide is of great help to specify safe margins and prosthesis positioning. Longer follow-up is needed to ensure that the rate of late loosening will not be too high.