Intraoperative extrakorporale Irradiation und Replantation (IEIR) in der lokalen Behandlung prim�r maligner Knochentumoren

Does Extracorporeal Irradiation and Reimplantation After Acetabular Resections Result in Adequate Hip Function? A Preliminary Report

BACKGROUND

Pelvic resections are challenging, and reconstruction of the resected acetabulum to restore mobility and stability is even more difficult. Extracorporeal radiation therapy (ECRT or extracorporeal irradiation) of autograft bone and reimplantation allows for a perfect size match and has been used with some success in the extremities. Although the risk of wound complications in pelvic surgery has discouraged surgeons from using ECRT of autografts in that anatomic site, we believe it may be a reasonable option.

QUESTIONS/PURPOSES

In a small series, we asked: (1) What was the median surgical time and blood loss for these procedures, and what early complications were observed? (2) Is there evidence of osteonecrosis or cartilage loss at a minimum of 2 years after ECRT of acetabular autografts, and what functional scores were achieved? (3) What were the oncologic outcomes after ECRT?

METHODS

Between March 2007 and September 2016, one surgeon performed 12 ECRT acetabular autografts and reimplantations after resections of pelvic or acetabular tumors. Of those, 10 with minimum 2-year followup are reported on here with respect to oncologic, functional, and radiographic assessment; all 12 are reported on for purposes of surgical parameters and early complications. During that period, we generally performed this approach when we judged it possible to achieve a tumor-free margin, adequate bone stock, and sufficient remaining hip musculature to allow use of the bone as an autograft with restoration of hip mobility. We generally did not use this approach when we anticipated a difficult resection with uncertain margins or where remaining bone was judged of poor strength for use as a graft or if both iliopsoas and abductors were sacrificed. Since 2010, this series represents seven of the 21 pelvic resections with reconstruction that we performed (five patients in this series had the procedure performed before 2010). Followup was at a median of 65 months (range, 33-114 months) for nine patients whose functional outcomes were evaluated. The median patient age was 30 years (range, 10-64 years). Clinical parameters were recorded from chart review; radiographic analysis for assessment of cartilage was performed by looking for any obvious loss of joint space when compared with the opposite side. Functional scoring was done using the Musculoskeletal Tumor Society score, which was obtained from chart review. Oncologic assessment was determined for local recurrence as well as metastases.

RESULTS

Median surgical time was 8.6 hours and median blood loss was 2250 mL. There were no perioperative wound-related complications. Two patients underwent a second surgical procedure during the postoperative period, one for a femoral artery thrombus and another for a complete sciatic nerve deficit. No patients developed avascular necrosis of the femoral head. None of the patients who underwent osteoarticular grafting showed radiographic evidence of joint space narrowing. The median Musculoskeletal Tumor Society score was 28 (range, 17-30). No fractures in the radiated segment of reimplanted bone were seen in this small series.

CONCLUSIONS

Results from this small series suggest that ECRT is a potential option in selected patients who have good bone stock and adequate soft tissue coverage. Although technically challenging, ECRT is a low-cost alternative to prostheses in providing a mobile and stable hip. Although we did not observe cartilage wear on plain radiographs, followup here was short term; it may appear as we continue to follow these patients. Future studies from retrieval specimens may shed light on the actual status of cartilage on the acetabulum.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

En bloc resection, intraoperative extracorporeal irradiation and re-implantation of involved bone for the treatment of limb malignancies

Reconstruction of the defect following limb-sparing resection of malignant bone tumors is controversial and extremely challenging. Extracorporeal irradiation (ECI) and re-implantation have been used for limb salvage surgery for patients, with major advantages, including biological reconstruction, ready availability and preservation of bone stock, over replacement with a megaprosthesis. The purpose of the present study was to present our experience and details of all patients treated with this surgery. Between June 2005 and December 2014, we followed-up 23 patients with limb malignancies who were treated with en bloc excision followed by 50-Gy single dose ECI and re-implantation of involved bone segments. All cases were evaluated based on clinical and radiological examinations, complications and Musculoskeletal Tumor Society (MSTS) score. Mean follow-up period was 77.6 months (range, 17-116 months). A total of 17 patients (73.9%) demonstrated no evidence of disease, 5 (21.7%) patients succumbed to the disease and 1 (4.3%) patient was alive with the disease at the final follow-up. Local recurrence occurred in 3 patients (recurrence rate, 13.0%) in the bed outside of the irradiated graft, and 4 of the 5 patients that lost their lives did so due to associated metastatic disease. The mean value of the MSTS score was 78.8% (50-93.3%). The majority of patients demonstrated solid bony union; however, 3 patients had non-union (13.0%) and 1 had a delayed union (4.3%). Early or late complications occurred in 11 patients (47.8%). Although the complication rate (47.8%) and re-operation rate (39.1%) were high, ECI and re-implantation may be a useful and cheap technique following en bloc resection for limb salvage in appropriately selected patients.

[Extracorporeal irradiation : Reimplantation of bone segments in the treatment of malignant bone tumours]

BACKGROUND

Malignant bone tumors themselves and the wide resection required because of them may cause huge bone defects in the bone segment involved. Autologous bone grafts are a reliable option to cover these defects in many cases but their availability is limited. Besides common alternative reconstruction methods, including the use of allografts and/or prostheses, especially extracoroporeal irradiation (ECI) and reimplantation of the bone segment involved is attracting increasingly more attention nowadays.

DISCUSSION

In the following, we report on indications/contraindications, details of the operative technique, as well as the recommended rehabilitation regime of ECI. Furthermore, we compare our own results with those published in the recent literature. Especially the advantages and disadvantages of this method, the risks and the complications are illustrated and critically discussed.

CONCLUSION

Extracorporeal irradiation of a tumor bearing bone segment is a valuable alternative reconstruction technique following tumor resections of the pelvis, femur and tibia, with encouraging results with respect to local control, complication risks and functional outcome.

The mechanical effects of extracorporeal irradiation on bone

Extracorporeal irradiation of an excised tumour-bearing segment of bone followed by its re-implantation is a technique used in bone sarcoma surgery for limb salvage when the bone is of reasonable quality. There is no agreement among previous studies about the dose of irradiation to be given: up to 300 Gy have been used. We investigated the influence of extracorporeal irradiation on the elastic and viscoelastic properties of bone. Bone was harvested from mature cattle and subdivided into 13 groups: 12 were exposed to increasing levels of irradiation: one was not and was used as a control. The specimens, once irradiated, underwent mechanical testing in saline at 37°C. The mechanical properties of each group, including Young's modulus, storage modulus and loss modulus, were determined experimentally and compared with the control group. There were insignificant changes in all of these mechanical properties with an increasing level of irradiation. We conclude that the overall mechanical effect of high levels of extracorporeal irradiation (300 Gy) on bone is negligible. Consequently the dose can be maximised to reduce the risk of local tumour recurrence.

Saving a Child's Elbow Joint: A Novel Reconstruction for a Tumour of the Distal Humerus

Reconstruction after wide resection of a malignant bone tumor can be obtained using several techniques such as the use of prostheses, allograft, autograft, or combined procedure. We describe a 12-year-old girl with parosteal osteosarcoma of the distal right humerus treated by en bloc resection, intraoperative extracorporeal irradiation, and implantation. We inserted a nonvascularised fibular autograft through the middle of irradiated graft to obtain a greater stability. We have not recorded any complication associated with this technique such as nonunion, pathological fracture, infection, and bone necrosis and we obtained an excellent functional result. 10 years after surgery, the patient had no recurrence. Extracorporeal irradiation and reimplantation is a valid and inexpensive technique for the treatment of bone tumors when there is reasonable residual bone stock. With this procedure we have a precise fit being the patient's own bone. In this way we avoid all the problems related to the adaptation of the shape and size.

Recycling of extracorporeally irradiated autograft for malignant bone tumors: long-term follow-up

This study was conducted to evaluate the long-term oncological and functional outcomes. Forty-two patients (29 men and 13 women) with primary malignant bone tumors were included in this study. The procedure consisted of wide en bloc resection, clearing the extraosseous soft tissue and medullary content, extracorporeal irradiation with a single dose of 50 Gy using linear accelerator, and reimplantation using suitable fixation devices. The mean survivor follow-up was 54 months (24-174 months). There were 32 (76.2%) patients continuously disease free, 7 (16.7%) died of disease, and 3 (7.1%) alive with disease. Local recurrence was encountered in 4 (9.5%) patients. Nonunion occurred at 3 (6.4%) osteotomy sites. Deep infection developed in 4 (9.5%) cases. There were 13 patients rated excellent, 17 good, 10 fair, and 2 failures according to the Mankin scoring system. The mean ratings of the Musculoskeletal Tumor Society score and the Toronto Extremity Salvage Score were 77 and 81, respectively. The long-term oncological and functional results are encouraging and suggest that extracorporeal irradiation and reimplantation can be a long-lasting biological reconstructive technique in properly selected patients.

Autoclaved tumor bone for skeletal reconstruction in paediatric patients: a low cost alternative in developing countries

We reviewed in this series forty patients of pediatric age who underwent resection for malignant tumors of musculoskeletal system followed by biological reconstruction. Our surgical procedure for reconstruction included (1) wide en bloc resection of the tumor; (2) curettage of tumor from the resected bone; (3) autoclaving for 8 minutes (4) bone grafting from the fibula (both vascularized and nonvascularized fibular grafts used); (5) reimplantation of the autoclaved bone into the host bone defect and fixation with plates. Functional evaluation was done using MSTS scoring system. At final followup of at least 18 months (mean 29.2 months), 31 patients had recovered without any complications. Thirty-eight patients successfully achieved a solid bony union between the graft and recipient bone. Three patients had surgical site infection. They were managed with wound debridement and flap coverage of the defect. Local recurrence and nonunion occurred in two patients each. One patient underwent disarticulation at hip due to extensive local disease and one died of metastasis. For patients with non-union, revision procedure with bone graft and compression plates was successfully used. The use of autoclaved tumor grafts provides a limb salvage option that is inexpensive and independent of external resources and is a viable option for musculoskeletal tumor management in developing countries.

[Primary malignant bone tumors]

Among human neoplasms, primary malignant bone tumors are fairly rare. They present an incidence rate of roughly 10 cases per 1 million inhabitants per year. During childhood (<15 years), the percentage of malignant bone tumors amounts to 6% of all infantile malignancies. Only leukemia and lymphoma show a higher incidence in adolescence. Of all primary malignant bone tumors, 60% affect patients younger than 45 years and the peak incidence of all bone tumors occurs between 15 and 19 years. The most common primary malignant bone tumors are osteosarcoma (35%), chondrosarcoma (25%), and Ewing's sarcoma (16%). Less frequently (≤ 5%) occurring tumors are chordoma, malignant fibrous histiocytoma of bone, and fibrosarcoma of bone. Vascular primary malignant tumors of bone and adamantinoma are very rare. Staging of the lesion is essential for systemic therapeutic decision-making and includes complete imaging and histo-pathological confirmation of the suspected entity. In most cases, this is established by open- or image-guided biopsy. Based on this information, an interdisciplinary tumor board will determine the individual therapeutic approach. Endoprosthetic or biological reconstruction following wide tumor resection is the most common surgical therapy for primary malignant bone tumors. There is vital importance in a thorough postoperative follow-up and continous after-care by a competent tumor center which is permanentely in charge of therapy.

Revision of tumor prosthesis of the knee joint

Background

Among 40 patients with primary malignant tumors of the knee joint who underwent reconstruction of the affected limb with tumor prosthesis, revision was required in 7 due to stem breakage or loosening.

Subjects and methods

In the 7 cases undergoing revision, conditions and background factors at the time of breakage, the breakage site, time of revision, models of previous and new prostheses, stem diameters before and after revision, details of the revision (blood loss, operative time), and the presence or absence of adjuvant therapy were determined.

Results

The replacement site was the distal femur in 5 and proximal tibia in 2. Revision was performed 6 years and 2 months after the previous prosthesis placement on average. The broken prosthesis model was KMFTR in 4 and HMRS and the physio-hinge type in one each. Revision due to loosening was performed in a case requiring replacement with Growing Kotz prosthesis. The model was switched to HMRS in 3, and the stem diameter was changed to 12 mm in 3 KMFTR breakage cases. The mean stem diameters were 11.2 and 10.2 mm in the non-revision and revision groups. The respective resection rates were 36 and 45%. The mean functional evaluation was 70.1% before and 76.2% after revision.

Conclusion

To reduce the risk of tumor prosthesis breakage, the amount of bone resection should be limited to 30% or less in the affected bone, the stem diameter should be at least 12 mm, and the stem shape should be fitted to the anatomical shape of the femur.

Analysis of limb function after various reconstruction methods according to tumor location following resection of pediatric malignant bone tumors

Background

In the reconstruction of the affected limb in pediatric malignant bone tumors, since the loss of joint function affects limb-length discrepancy expected in the future, reconstruction methods that not only maximally preserve the joint function but also maintain good limb function are necessary. We analysis limb function of reconstruction methods by tumor location following resection of pediatric malignant bone tumors.

Patients and methods

We classified the tumors according to their location into 3 types by preoperative MRI, and evaluated reconstruction methods after wide resection, paying attention to whether the joint function could be preserved. The mean age of the patients was 10.6 years, Osteosarcoma was observed in 26 patients, Ewing's sarcoma in 3, and PNET(primitive neuroectodermal tumor) and chondrosarcoma (grade 1) in 1 each.

Results

Type I were those located in the diaphysis, and reconstruction was performed using a vascularized fibular graft(vascularized fibular graft). Type 2 were those located in contact with the epiphyseal line or within 1 cm from this line, and VFG was performed in 1, and distraction osteogenesis in 1. Type III were those extending from the diaphysis to the epiphysis beyond the epiphyseal line, and a Growing Kotz was mainly used in 10 patients. The mean functional assessment score was the highest for Type I (96%: n = 4) according to the type and for VFG (99%) according to the reconstruction method.

Conclusion

The final functional results were the most satisfactory for Types I and II according to tumor location. Biological reconstruction such as VFG and distraction osteogenesis without a prosthesis are so high score in the MSTS rating system. Therefore, considering the function of the affected limb, a limb reconstruction method allowing the maximal preservation of joint function should be selected after careful evaluation of the effects of chemotherapy and the location of the tumor.

The role of radiotherapy in oseosarcoma

A survey of the literature shows that the experience with radiotherapy (RT) in the local treatment of osteosarcoma (OS) is limited. This is due to various reasons: OS is a rare tumor and surgery is the treatment of choice with high local control rate, and uncertainty exists in regard to the efficacy and tolerance of radiotherapy. Publications on this topic were analyzed and will be reviewed. Furthermore, experience from the Cooperative Osteosarkomstudiengruppe (COSS)-Registry, including 100 patients (pts) treated using radiotherapy for OS, was analyzed. The COSS-registry includes a total of 175 pts (5% of all pts) with histologically proven OS irradiated over the period of 1980-2007. 100 pts were eligible for analysis. The median age was 18 (3-66) years. Indication for RT was a primary tumor in 66, a local recurrence in 11, and metastases in 23 pts. 94 pts got external photontherapy; 2 pts, proton therapy; 2 pts, neutron therapy; and 2 pts, intraoperative RT. In addition, a group of 17 pts received bone-targeted radionuclide therapy by samarium-153-EDTMP-therapy alone or in combination with external RT. The median dose for external RT was 55.8 Gy (30-120). All the pts received chemotherapy in accordance with different COSS-protocols. The median follow-up was 1.5 (0.2-23) years. Survival and local control rates at 5 years were calculated, and univariate and multivariate analyses performed. 41 pts are alive, 59 pts died. The overall survival rate after biopsy was 41% at 5 years, while the overall survival rates after RT for the whole group, for treatment of primary tumors, local recurrence, and metastases were 36%, 55%, 15%, and 0% respectively.In 41 cases, local control was achieved, whereas local progression or local recurrence occurred in 59 cases, with a median time to local recurrence of 0.5 (0.1-4) years after RT. 15 pts were nonresponders to radiotherapy. Local control for the whole group was 30%. Local control rates for combined surgery and RT were significantly better than those for RT alone (48% vs. 22%, p=0.002). Local control for treatment of primary tumors, local recurrence, and metastases were 40%, 17%, and 0% respectively. Local control for pts given an addition of samarium-153-EDTMP was poor, though not statistically significant. A dose of over 60 Gy had no significant effect on local control. Prognostic factors for survival were indication for RT, RT plus surgery vs. RT alone and tumor location. Prognostic factors for local control were indication for RT, and RT plus surgery vs. RT alone. For the majority of pts, surgery remains the local treatment of choice. Radiotherapy is an important option as local treatment of unresectable tumors, following intralesional resection, or as palliation of symptomatic metastases. Survival prognosis of such pts, however, is poor. Despite the fact that many of these pts will eventually die, they may benefit in terms of prolonged survival and prolonged local control. The combination of surgery, radiotherapy, and chemotherapy can be curative. The consistent use of full-dose chemotherapy is of importance for the response to radiotherapy. Prognostic factors for survival are indication for RT, RT plus surgery vs. RT alone and tumor location. Prognostic factors for local control are indication for RT, and RT plus surgery vs. RT alone.

Methods of biological reconstruction for bone sarcoma: indications and limits

Therapy of bone sarcoma has dramatically changed over the past few decades. Several successful interdisciplinary treatment strategies have led to an increase of the survival rates from 20% to 60%-80%. Consequently new demands on the operative treatment of bone and soft tissue sarcoma have arisen. Nowadays limb salvage can be achieved in 80%-90% using tumour megaprostheses or biological reconstruction procedures. In this article we outline the indications and limitations of biological reconstruction procedures after bone tumour resection. We therefore introduce the different biological approaches such as free autologous bone grafting, reimplantation of extracorporeal devitalized autografts or distraction osteogenesis and summarize the currently available data on the individual procedures. Our analyses demonstrate a wide applicability of biological procedures in tumour situations. Although accompanied by considerable complications in the early postoperative phase, biological reconstructions clearly demonstrate the potential of having excellent long-term durability and functionality.

Intercalary femoral reconstruction with extracorporeal irradiated autogenous bone graft in limb-salvage surgery

Between 1996 and 2003, 16 patients (nine female, seven male) were treated for a primary bone sarcoma of the femur by wide local excision of the tumour, extracorporeal irradiation and re-implantation. An additional vascularised fibular graft was used in 13 patients (81%). All patients were free from disease when reviewed at a minimum of two years postoperatively (mean 49.7 months (24 to 96). There were no cases of infection. Primary union was achieved after a median of nine months (interquartile range 7 to 11). Five host-donor junctions (16%) united only after a second procedure. Primary union recurred faster at metaphyseal junctions (94% (15) at a median of 7.5 months (interquartile range 4 to 12)) than at diaphyseal junctions (75% (12) at a median of 11.1 months (interquartile range 5 to 18)). Post-operatively, the median Musculoskeletal Tumour Society score was 85% (interquartile range 75 to 96) and the median Toronto Extremity Salvage score 94% (interquartile range 82 to 99). The Mankin score gave a good or excellent result in 14 patients (88%). The range of movement of the knee was significantly worse when the extracorporeally irradiated autografts were fixed by plates rather than by nails (p = 0.035). A total of 16 (62%) of the junctions of the vascularised fibular grafts underwent hypertrophy, indicating union and loading. Extracorporeal irradiation autografting with supplementary vascularised fibular grafting is a promising biological alternative for intercalary reconstruction after wide resection of malignant bone tumours of the femur.

intraoperative radiation therapy part 2. Clinical results

Intraoperative radiation therapy (IORT) has been used for over 30 years in Asia, Europe and America as a supplementary activity in the treatment of cancer patients with promising results. Modern IORT is carried out with electron beams (IOERT) produced by a linear accelerator generally used for external beam irradiation (EBRT) or a specialized mobile electron accelerator. HDR brachytherapy (HDR-IORT) has also been applied on selected locations. Retrospective analysis of clinical experiences in cancer sites such as operable pancreatic tumour, locally advanced/recurrent rectal cancer, head and neck carcinomas, sarcomas and cervical cancer are consistent with local tumour control promotion compared to similar clinical experiences without IORT. New emerging indications such as the treatment of breast cancer are presented. The IORT component of the therapeutical approach allows intensification of the total radiation dose without additional exposure of healthy tissues and improves dose-deposit homogeneity and precision. Results of the application of IORT on selected disease sites are presented with an analysis on future possibilities. To improve the methodology, clinical trials are required with multivariate analysis including patient, tumour and treatment characteristics, prospective evaluation of early and late toxicity, patterns of tumour recurrence and overall patient outcome.

En-bloc resection, extracorporeal irradiation, and re-implantation in limb salvage for bony malignancies

We treated 50 patients with bony malignancy by en-bloc resection, extracorporeal irradiation with 50 Gy and re-implantation of the bone segment.

The mean survivor follow-up was 38 months (12 to 92) when 42 patients were alive and without disease. There were four recurrences. The functional results were good according to the Mankin score (17 excellent, 13 good, nine fair, three failures), the Musculoskeletal Tumour Society score (mean 77) and the Toronto Extremity Salvage score (mean 81). There was solid union, but bone resorption was seen in some cases. The dose of radiation was lethal to all cells and produced a dead autograft of perfect fit.

Extracorporeal irradiation is a useful technique for limb salvage when there is reasonable residual bone stock. It allows effective re-attachment of tendons and produces a lasting biological reconstruction. There should be no risk of local recurrence or of radiotherapy-induced malignancy in the replanted bone.