Is there still a role for osteoarticular allograft reconstruction in musculoskeletal tumour surgery? a long-term follow-up study of 38 patients and systematic review of the literature

AIMS

To assess complications and failure mechanisms of osteoarticular allograft reconstructions for primary bone tumours.

PATIENTS AND METHODS

We retrospectively evaluated 38 patients (28 men, 74%) who were treated at our institution with osteoarticular allograft reconstruction between 1989 and 2010. Median age was 19 years (interquartile range 14 to 32). Median follow-up was 19.5 years (95% confidence interval (CI) 13.0 to 26.1) when 26 patients (68%) were alive. In addition, we systematically searched the literature for clinical studies on osteoarticular allografts, finding 31 studies suitable for analysis. Results of papers that reported on one site exclusively were pooled for comparison.

RESULTS

A total of 20 patients (53%) experienced graft failure, including 15 due to mechanical complications (39%) and three (9%) due to infection. In the systematic review, 514 reconstructions were analysed (distal femur, n = 184, 36%; proximal tibia, n = 136, 26%; distal radius, n = 99, 19%; proximal humerus, n = 95, 18%). Overall rates of failure, fracture and infection were 27%, 20%, and 10% respectively. With the distal femur as the reference, fractures were more common in the humerus (odds ratio (OR) 4.1, 95% CI 2.2 to 7.7) and tibia (OR 2.2, 95% CI 1.3 to 4.4); infections occurred more often in the tibia (OR 2.2, 95% CI 1.3 to 4.4) and less often in the radius (OR 0.1, 95% CI 0.0 to 0.8).

CONCLUSION

Osteoarticular allograft reconstructions are associated with high rates of mechanical complications. Although comparative studies with alternative techniques are scarce, the risk of mechanical failure in our opinion does not justify routine employment of osteoarticular allografts for reconstruction of large joints after tumour resection. Cite this article: Bone Joint J 2017;99-B:522-30.

MRI appearances of atypical cartilaginous tumour/grade I chondrosarcoma after treatment by curettage, phenolisation and allografting: recommendations for follow-up

AIMS

The purpose of this retrospective study was to differentiate between the MRI features of normal post-operative change and those of residual or recurrent disease after intralesional treatment of an atypical cartilage tumour (ACT)/grade I chondrosarcoma.

PATIENTS AND METHODS

We reviewed the case notes, radiology and histology of 75 patients, who had been treated for an ACT/grade I chondrosarcoma by curettage, phenolisation and bone allografting between 1994 and 2005. The first post-operative Gd-enhanced MRI scan was carried out within one year of surgery. Patients had a minimum of two scans and a mean follow-up of 72 months (13 to 169). Further surgery was undertaken in cases of suspected recurrence.

RESULTS

In 14 patients (18.6%) a second procedure was undertaken after a mean period of 59 months (8 to 114). Radio frequency ablation (RFA) was used in lesions of < 10 mm and curettage, phenolisation and bone grafting for those ≥ 10 mm. Only six of these (8% of total) had a histologically-proven recurrence. No increase in tumour grade was seen at time of recurrence.

CONCLUSION

Based on this study, we have been able to classify the post-operative MRI appearances into four groups. These groups differ in follow-up, and have a different risk of recurrence of the lesion. Follow-up and treatment vary for the patients in each group. We present a flow diagram for the appropriate and safe follow-up for this specific group of patients. Cite this article: Bone Joint J 2016;98-B:1674-81.

Intercalary allograft reconstructions following resection of primary bone tumors: a nationwide multicenter study

BACKGROUND

Favorable reports on the use of massive allografts to reconstruct intercalary defects underline their place in limb-salvage surgery. However, little is known about optimal indications as reports on failure and complication rates in larger populations remain scarce. We evaluated the incidence of and risk factors for failure and complications, time to full weight-bearing, and optimal fixation methods for intercalary allografts after tumor resection.

METHODS

A retrospective study was performed in all four centers of orthopaedic oncology in the Netherlands. All consecutive patients reconstructed with intercalary (whole-circumference) allografts after tumor resection in the long bones during 1989 to 2009 were evaluated. The minimum follow-up was twenty-four months. Eighty-seven patients with a median age of seventeen years (range, 1.5 to 77.5 years) matched inclusion criteria. The most common diagnoses were osteosarcoma, Ewing sarcoma, adamantinoma, and chondrosarcoma. The median follow-up period was eighty-four months (range, twenty-five to 262 months). Ninety percent of tumors were localized in the femur or the tibia.

RESULTS

Fifteen percent of our patients experienced a graft-related failure. The major complications were nonunion (40%), fracture (29%), and infection (14%). Complications occurred in 76% of patients and reoperations were necessary in 70% of patients. The median time to the latest complication was thirty-two months (range, zero to 200 months). The median time to full weight-bearing was nine months (range, one to eighty months). Fifteen grafts failed, twelve of which failed in the first four years. None of the thirty-four tibial reconstructions failed. Reconstruction site, patient age, allograft length, nail-only fixation, and non-bridging osteosynthesis were the most important risk factors for complications. Adjuvant chemotherapy and irradiation had no effects on complication rates.

CONCLUSIONS

We report high complication rates and considerable failure rates for the use of intercalary allografts; complications primarily occurred in the first years after surgery, but some occurred much later after surgery. To reduce the number of failures, we recommend reconsidering the use of allografts for reconstructions of defects that are ≥15 cm, especially in older patients, and applying bridging osteosynthesis with use of plate fixation.

Surgical technique: Tibia cortical strut autograft interposition arthrodesis after distal radius resection

BACKGROUND

Distal radius reconstruction after en bloc tumor resection remains a surgical challenge. Although several surgical techniques, either reconstructing the wrist or achieving a stable arthrodesis, have been described, it is unclear to what degree these restore function.

DESCRIPTION OF TECHNIQUE

We describe an updated technique making use of a tibia cortical strut autograft (TCSA) to perform a functional arthrodesis from the remaining radius to the first carpal row. This, in theory, could lead to less donor site morbidity while resulting in a stable but functional and pain-free arthrodesis of the wrist.

METHODS

Between 1987 and 2010 we reconstructed the wrists of 17 patients using a TCSA arthrodesis (six primary and three revisions), seven with an osteoarticular allograft, three using an ulnar translocation, and one with a fibula autograft. Median age at diagnosis was 24 years (range, 9-58 years) and minimum followup was 2.7 years (median, 13.8 years; range, 2.7-24.5 years). Patients were evaluated using radiographs and clinical examination. We used Musculoskeletal Tumor Society (MSTS), Disabilities of the Arm, Shoulder, and Hand (DASH), and SF-36 questionnaires to assess function and quality of life.

RESULTS

All TCSA reconstructions fused; one patient had a second surgery to expedite union with the carpal row. After osteoarticular allograft, five patients were revised (three to a TCSA) for nonunion, fracture, or joint collapse. ROM and grip strength were comparable in both AO and TCSA, all above 60% of the contralateral side. Median MSTS and DASH scores were 73% and 6, respectively, and did not differ between the groups. The SF-36 scores showed less pain after TCSA; otherwise, all patients presented with comparable function.

CONCLUSIONS

TCSA wrist arthrodesis resulted in a functional and painless wrist reconstruction with a relatively low complication and donor site morbidity rate and comparable functional results as other techniques.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Translation and preliminary validation of the English version of the DUX questionnaire for lower extremity bone tumor patients (Bt-DUX): a disease-specific measure for quality of life

PURPOSE

To translate the Dutch DUX questionnaire for lower extremity bone tumor patients (Bt-DUX), a disease-specific quality of life (QoL) instrument, into the English (UK) language and preliminary validate the English version in patients who were treated for lower-extremity bone tumors.

METHODS

Adaptation and translation process included forward translation, back-translation, and a review of the back-translation by an expert committee. Internal consistency and validity of the translated questionnaire were examined in a sample of adolescents treated for lower extremity osteosarcoma in the United Kingdom. Assessments included the Bt-DUX, the Toronto Extremity Salvage Score (TESS), the Short Form (SF)-36, and the TNO-AZL Questionnaire for Adult's Quality of Life (TAAQOL).

RESULTS

Seventeen patients (7 ♂ and 10 ♀), median age 19.9 (range: 16-25) years completed the questionnaires. Mean Bt-DUX score was 38.8 (range: 23-78), with Cronbach's α being 0.95 domain-total correlations ranged between 0.84 and 0.93 (P < 0.01). Spearman's correlation coefficients between the Bt-DUX total and domain scores and corresponding TAAQOL and SF-36 scores were overall moderate to good and reaching statistical significance in a most cases.

CONCLUSION

Preliminary evidence suggests that the English Bt-DUX translation is a valid disease-specific instrument for evaluating QoL of adolescents with lower extremity bone cancer.

Low-grade chondrosarcoma of long bones treated with intralesional curettage followed by application of phenol, ethanol, and bone-grafting

BACKGROUND

A common treatment of low-grade cartilaginous lesions of bone is intralesional curettage with local adjuvant therapy. Because of the wide variety of different diagnoses and treatments, there is still a lack of knowledge about the effectiveness of the use of phenol as local adjuvant therapy in patients with grade-I central chondrosarcoma of a long bone.

METHODS

A retrospective study was done to assess the clinical and oncological outcomes after intralesional curettage, application of phenol and ethanol, and bone-grafting in eighty-five patients treated between 1994 and 2005. Inclusion criteria were histologically proven grade-I central chondrosarcoma and location of the lesion in a long bone. The average age at surgery was 47.5 years (range, 15.6 to 72.3 years). The average duration of follow-up was 6.8 years (range, 0.2 to 14.1 years). Patients were evaluated periodically with conventional radiographs and gadolinium-enhanced magnetic resonance imaging (Gd-MRI) scans. When a lesion was suspected on the basis of the MRI, the patient underwent repeat intervention. Depending on the size of the recurrent lesion, biopsy followed by radiofrequency ablation (for lesions of <10 mm) or repeat curettage (for those of ≥10 mm) was performed.

RESULTS

Of the eighty-five patients, eleven underwent repeat surgery because a lesion was suspected on the basis of the Gd-MRI studies during follow-up. Of these eleven, five had a histologically proven local recurrence (a recurrence rate of 5.9% [95% confidence interval, 0.9% to 10.9%]), and all were grade-I chondrosarcomas. General complications consisted of one superficial infection, and two femoral fractures within six weeks after surgery.

CONCLUSIONS

This retrospective case series without controls has limitations, but the use of phenol as an adjuvant after intralesional curettage of low-grade chondrosarcoma of a long bone was safe and effective, with a recurrence rate of <6% at a mean of 6.8 years after treatment.

A prospective study on quality of life and functional outcome in children and adolescents after malignant bone tumor surgery

BACKGROUND

Few longitudinal data are available concerning quality of life (QoL) and functioning of young patients undergoing surgical procedures for malignant bone tumors around the knee joint. Aim of the present study was to evaluate patients' quality of life, functional ability, and physical activity during a 2-year postoperative period.

METHODS

This prospective study included patients who underwent surgery for a malignant bone tumor around the knee joint between 2004 and 2008. Assessments were done at 3, 6, 9, 12, 18, and 24 months after surgery. QoL was measured with the TNO-AZL Children's or Adult's Quality of Life Questionnaires (TACQOL and TAAQOL), the Short Form-36 (SF-36) and Bone tumor (Bt)-DUX; functional ability with the Toronto Extremity Salvage Scale (TESS), the 6-minute walk test (6 MWT) and four functional performance tests; and physical activity with the Baecke questionnaire and the ActiLog® activity monitor. Statistical analysis included linear mixed model analysis.

RESULTS

Forty-four patients (27 males, 17 females, mean age 14.9 (SD 4.8) years) were included, 27 (61%) underwent limb-salvage and 17 (39%) ablative surgery. Twenty patients were lost during the 2 years follow-up as a consequence of oncological complications. Over the first year, survivors showed significant improvement of QoL, functional ability and physical activity, except for the mental dimension of the SF-36 and the activity monitor results. Over the second year, these improvements were less pronounced.

CONCLUSIONS

In the first 2 years after bone tumor surgery, survivors improved significantly with respect to QoL, functional ability, and physical activity levels.

Incidence, predictive factors, and prognosis of chondrosarcoma in patients with Ollier disease and Maffucci syndrome: an international multicenter study of 161 patients

BACKGROUND

Enchondromatosis is characterized by the presence of multiple benign cartilage lesions in bone. While Ollier disease is typified by multiple enchondromas, in Maffucci syndrome these are associated with hemangiomas. Studies evaluating the predictive value of clinical symptoms for development of secondary chondrosarcoma and prognosis are lacking. This multi-institute study evaluates the clinical characteristics of patients, to get better insight on behavior and prognosis of these diseases.

METHOD

A retrospective study was conducted using clinical data of 144 Ollier and 17 Maffucci patients from 13 European centers and one national databank supplied by members of the European Musculoskeletal Oncology Society.

RESULTS

Patients had multiple enchondromas in the hands and feet only (group I, 18%), in long bones including scapula and pelvis only (group II, 39%), and in both small and long/flat bones (group III, 43%), respectively. The overall incidence of chondrosarcoma thus far is 40%. In group I, only 4 patients (15%) developed chondrosarcoma, in contrast to 27 patients (43%) in group II and 26 patients (46%) in group III, respectively. The risk of developing chondrosarcoma is increased when enchondromas are located in the pelvis (odds ratio, 3.8; p = 0.00l).

CONCLUSIONS

Overall incidence of development of chondrosarcoma is 40%, but may, due to age-dependency, increase when considered as a lifelong risk. Patients with enchondromas located in long bones or axial skeleton, especially the pelvis, have a seriously increased risk of developing chondrosarcoma, and are identified as the population that needs regular screening on early detection of malignant transformation.

Presence of chemotherapy-induced toxicity predicts improved survival in patients with localised extremity osteosarcoma treated with doxorubicin and cisplatin: a report from the European Osteosarcoma Intergroup

Aim

Chemotherapy-induced toxicity is an independent prognostic indicator in several cancers. We aimed to determine whether toxicity was related to survival and histological response in high-grade localised extremity osteosarcoma. We undertook a retrospective analysis of patients treated within three consecutive randomised controlled trials (RCTs) of the European Osteosarcoma Intergroup.

Methods

Between 1982 and 2002, 533 patients were randomised to six cycles of doxorubicin 75 mg/m² and cisplatin 100 mg/m². Toxicity data were collected prospectively and graded according to the World Health Organisation (WHO) criteria. Standard univariate and multivariate models were constructed to examine the relationship between reported toxicity, survival, and histological response.

Results

Five- and 10-year overall survival was 57% (95% confidence interval (CI) 52–61%) and 53% (49–58%), respectively. Grades 3–4 oral mucositis (hazard ratio (HR) 0.51, 95% CI 0.29–0.91), grades 1–2 nausea/vomiting (HR 0.37, 95% CI 0.16–0.85), grades 1–2 thrombocytopenia (HR 0.49, 95% CI 0.27–0.87), good histological response (HR 0.42, 95% CI 0.27–0.65), and distal tumour site (HR 0.45, 95% CI 0.28–0.71) were associated with improved survival in multivariate analysis. The only factors that were independently associated with histological response were older age (odds ratio (OR) 0.18, 95% CI 0.04–0.72) and chondroblastic tumour (OR 0.28, 95% CI 0.10–0.77), both being associated with a significantly lower chance of achieving a good response.

Conclusion

Chemotherapy-induced toxicity predicts survival in patients with localised extremity osteosarcoma. Investigation of the pharmacogenomic mechanisms of constitutional chemosensitivity underlying these observations will present opportunities for personalising treatment and could lead to improved outcomes.

Survival from high-grade localised extremity osteosarcoma: combined results and prognostic factors from three European Osteosarcoma Intergroup randomised controlled trials

BACKGROUND

Neoadjuvant chemotherapy improves outcome in osteosarcoma. Determination of optimum regimens for survival, toxicity and prognostic factors requires randomised controlled trials to be conducted.

PATIENTS AND METHODS

Between 1983 and 2002, the European Osteosarcoma Intergroup recruited 1067 patients with localised extremity osteosarcoma to three randomised controlled trials. Standard treatment in each was doxorubicin 75 mg/m(2) and cisplatin 100 mg/m(2). Comparators were addition of methotrexate (BO02/80831), a multidrug regimen (BO03/80861) and a dose-intense schedule (BO06/80931). Standard survival analysis methods were used to identify prognostic factors, temporal and other influences on outcome.

RESULTS

Five- and 10-year survival were 56% (95% confidence interval 53% to 59%) and 52%, respectively (49% to 55%), with no difference between trials or treatment arms. Median follow-up was 9.4 years. Age range was 3-40 years (median 15). Limb salvage was achieved in 69%. Five hundred and thirty-three patients received the standard arm, 79% completing treatment. Good histological response to preoperative chemotherapy, distal tumour location (all sites other than proximal humerus/femur) and female gender were associated with improved survival.

CONCLUSIONS

Localised osteosarcoma will be cured in 50% of patients with cisplatin and doxorubicin. Large randomised trials can be conducted in this rare cancer. Failure to improve survival over 20 years argues for concerted collaborative international efforts to identify and rapidly test new treatments.

Quality of life, functional ability and physical activity after different surgical interventions for bone cancer of the leg: A systematic review

PURPOSE

To systematically review published studies comparing Quality of Life (QoL), functional ability and/or physical activity between different surgical interventions due to a malignant bone tumour of the leg.

METHODS

A systematic literature search, covering the years 2000-2010 was performed using the PubMed, Embase, Web of science and Cochrane databases. Studies were included if they described and statistically compared QoL, functional ability and/or physical activity of at least two surgical interventions for lower extremity bone cancer. In addition, the methodological quality of the selected studies was evaluated by using a 24-point scale. Where appropriate, a qualitative analysis or meta-analysis was performed.

RESULTS

The search strategy resulted in a list of 246 citations. Based on titles and abstracts 50 full-text articles were selected, of which 13 articles describing 12 studies, were finally included. Overall, the methodological quality of the studies was moderate. Studies were heterogeneous with respect to their categorisation of surgical interventions, average age of patients and average duration of follow-up. Overall, results regarding differences between ablative and limb-sparing surgery varied largely. Meta-analysis was considered to be not appropriate due to clinical heterogeneity, methodological differences and flaws.

CONCLUSION

Twelve studies comparing the outcomes of QoL, functional ability and physical activity between limb-sparing and ablative surgery groups were identified, with an overall moderate methodological quality. Their largely varying outcomes suggest that no general conclusions on the advantage of either limb-sparing or ablative surgery in patients with malignant bone tumours of the lower extremity can be drawn.

Chemotherapy-resistant osteosarcoma is highly susceptible to IL-15-activated allogeneic and autologous NK cells

High-grade osteosarcoma occurs predominantly in adolescents and young adults and has an overall survival rate of about 60%, despite chemotherapy and surgery. Therefore, novel treatment modalities are needed to prevent or treat recurrent disease. Natural killer (NK) cells are lymphocytes with cytotoxic activity toward virus-infected or malignant cells. We explored the feasibility of autologous and allogeneic NK cell-mediated therapies for chemotherapy-resistant and chemotherapy-sensitive high-grade osteosarcoma. The expression by osteosarcoma cells of ligands for activating NK cell receptors was studied in vitro and in vivo, and their contribution to NK cell-mediated cytolysis was studied by specific antibody blockade. Chromium release cytotoxicity assays revealed chemotherapy-sensitive and chemotherapy-resistant osteosarcoma cell lines and osteosarcoma primary cultures to be sensitive to NK cell-mediated cytolysis. Cytolytic activity was strongly enhanced by IL-15 activation and was dependent on DNAM-1 and NKG2D pathways. Autologous and allogeneic activated NK cells lysed osteosarcoma primary cultures equally well. Osteosarcoma patient-derived NK cells were functionally and phenotypically unimpaired. In conclusion, osteosarcoma cells, including chemoresistant variants, are highly susceptible to lysis by IL-15-induced NK cells from both allogeneic and autologous origin. Our data support the exploitation of NK cells or NK cell-activating agents in patients with high-grade osteosarcoma.

Genome-wide analysis of Ollier disease: Is it all in the genes?

Background

Ollier disease is a rare, non-hereditary disorder which is characterized by the presence of multiple enchondromas (ECs), benign cartilaginous neoplasms arising within the medulla of the bone, with an asymmetric distribution. The risk of malignant transformation towards central chondrosarcoma (CS) is increased up to 35%. The aetiology of Ollier disease is unknown.

Methods

We undertook genome-wide copy number and loss of heterozygosity (LOH) analysis using Affymetrix SNP 6.0 array on 37 tumours of 28 Ollier patients in combination with expression array using Illumina BeadArray v3.0 for 7 ECs of 6 patients.

Results

Non-recurrent EC specific copy number alterations were found at FAM86D, PRKG1 and ANKS1B. LOH with copy number loss of chromosome 6 was found in two ECs from two unrelated Ollier patients. One of these patients also had LOH at chromosome 3. However, no common genomic alterations were found for all ECs. Using an integration approach of SNP and expression array we identified loss as well as down regulation of POU5F1 and gain as well as up regulation of NIPBL. None of these candidate regions were affected in more than two Ollier patients suggesting these changes to be random secondary events in EC development. An increased number of genetic alterations and LOH were found in Ollier CS which mainly involves chromosomes 9p, 6q, 5q and 3p.

Conclusions

We present the first genome-wide analysis of the largest international series of Ollier ECs and CS reported so far and demonstrate that copy number alterations and LOH are rare and non-recurrent in Ollier ECs while secondary CS are genetically unstable. One could predict that instead small deletions, point mutations or epigenetic mechanisms play a role in the origin of ECs of Ollier disease.

Quality of life in young patients after bone tumor surgery around the knee joint and comparison with healthy controls

BACKGROUND

This study aimed to compare the health related quality of life (HRQoL) of children and adolescents after malignant bone tumor surgery of the leg with healthy controls.

PROCEDURE

Patients between 8 and 25 years old were cross-sectional recruited. Patients under 16 years of age received the TNO (Netherlands Organization for Applied Scientific Research) and AZL (Leiden University Medical Center) Children's Quality of Life Questionnaire (TACQOL), patients aged 16 years and older received the TNO-AZL Questionnaire for Adult's Quality of Life (TAAQOL) and the Short Form-36 (SF-36). Three age- and sex-matched normative random samples, drawn from large, nationwide studies, were used for the comparison with healthy controls. Patients were interviewed regarding their most important problems related to the disease and its treatment.

RESULTS

Eighty-one patients with a mean age of 16.9 years (SD 4.2) were included (41 female). Limb sparing surgery was executed in 38 patients, ablative surgery in 43 patients. In comparison with healthy controls, patients had significantly poorer HRQoL within the domains autonomy and motor function of the TACQOL, gross motor function, cognitive functioning, daily functioning and sexuality of the TAAQOL, and physical functioning, role physical, general health, and the physical and mental component summary scales of the SF-36. Patients reported limitations in physical activities, participation in sports, and cosmetic aspects as the most detrimental consequences of their disease and its treatment.

CONCLUSION

In children and adolescents who underwent surgery for a malignant tumor of the leg physical, functioning was significantly impaired as compared to healthy controls.

Prognostic factors in pulmonary metastasized high-grade osteosarcoma

INTRODUCTION

Resection of pulmonary metastases has previously been reported to improve outcome in high-grade osteosarcoma (OS) patients. Factors influencing survival in OS patients with pulmonary metastases are important for clinical decision making.

METHODS

All 88 OS patients with pulmonary metastases either at diagnosis or during follow-up treated at the Leiden University Medical Center between January 1, 1990 and January 1, 2008 under the age of 40 were included in this study, including 79 cases of conventional, 8 cases of telangiectatic and 1 case of small cell OS.

RESULTS

In total, 56 of 88 patients with pulmonary metastases were treated by metastasectomy. Resectability of pulmonary metastases was the main prognostic factor. In patients with primary non-metastatic OS, a longer relapse free interval to pulmonary metastases was significantly associated with better survival (P = 0.02). Independent risk factors determining worse survival after metastasectomy in multivariate analysis were male sex (P = 0.05), higher number of pulmonary nodules (P = 0.03), and non-necrotic metastases (P = 0.04). Whether surgery for recurrent pulmonary metastases was performed did not influence survival. Histological subtype of the primary tumor, histological response in the primary tumor after neo-adjuvant chemotherapy, occurrence of local relapse, local resection or amputation of the primary tumor and age at diagnosis did not influence outcome.

CONCLUSION

This cohort of patients with detailed follow-up data enabled us to identify important risk factors determining survival in OS patients with pulmonary metastases. We demonstrate that after repeated metastasectomies, a subset of patients can be cured.

A balanced t(5;17) (p15;q22-23) in chondroblastoma: frequency of the re-arrangement and analysis of the candidate genes

Background

Chondroblastoma is a benign cartilaginous tumour of bone that predominantly affects the epiphysis of long bones in young males. No recurrent chromosomal re-arrangements have so far been observed. Methods: We identified an index case with a balanced translocation by Combined Binary Ratio-Fluorescent in situ Hybridisation (COBRA-FISH) karyotyping followed by breakpoint FISH mapping and array-Comparative Genomic Hybridisation (aCGH). Candidate region re-arrangement and candidate gene expression were subsequently investigated by interphase FISH and immunohistochemistry in another 14 cases.

Results

A balanced t(5;17)(p15;q22-23) was identified. In the index case, interphase FISH showed that the translocation was present only in mononucleated cells and was absent in the characteristic multinucleated giant cells. The t(5;17) translocation was not observed in the other cases studied. The breakpoint in 5p15 occurred close to the steroid reductase 5α1 (SRD5A1) gene. Expression of the protein was found in all cases tested. Similar expression was found for the sex steroid signalling-related molecules oestrogen receptor alpha and aromatase, while androgen receptors were only found in isolated cells in a few cases. The breakpoint in 17q22-23 was upstream of the carbonic anhydrase × (CA10) gene region and possibly involved gene-regulatory elements, which was indicated by the lack of CA10 protein expression in the index case. All other cases showed variable levels of CA10 expression, with low expression in three cases.

Conclusion

We report a novel t(5;17)(p15;q22-23) translocation in chondroblastoma without involvement of any of the two chromosomal regions in other cases studied. Our results indicate that the characteristic multinucleated giant cells in chondroblastoma do not have the same clonal origin as the mononuclear population, as they do not harbour the same translocation. We therefore hypothesise that they might be either reactive or originate from a distinct neoplastic clone, although the occurrence of two distinct clones is unlikely. Impairment of the CA10 gene might be pathogenetically relevant, as low expression was found in four cases. Diffuse expression of SRD5A1 and sex steroid signalling-related molecules confirms their role in neoplastic chondrogenesis.

Profiling of high-grade central osteosarcoma and its putative progenitor cells identifies tumourigenic pathways

Background:

Osteosarcoma is the most prevalent primary malignant bone tumour in children and young adults, with poor survival in 40% of patients. To identify the signalling pathways involved in tumourigenesis, we compared gene expression in osteosarcoma with that in its presumed normal counterparts.

Methods:

Genome-wide expression profiles were generated from 25 high-grade central osteosarcoma prechemotherapy biopsies, 5 osteoblastomas, 5 mesenchymal stem cell (MSC) populations and these same MSCs differentiated into osteoblasts. Genes that were differentially expressed were analysed in the context of the pathways in which they function using the GenMAPP programme.

Results:

MSCs, osteoblasts, osteoblastomas and osteosarcomas clustered separately and thousands of differentially expressed genes were identified. The most significantly altered pathways are involved in cell cycle regulation and DNA replication. Several upstream components of the Wnt signalling pathway are downregulated in osteosarcoma. Two genes involved in degradation of β-catenin protein, the key effectors of Wnt signalling, Axin and GSK3-β, show decreased expression, suggesting that Wnt signalling is no longer under the control of regular signals. Comparing benign osteoblastomas with osteosarcomas identified cell cycle regulation as the most prominently changed pathway.

Conclusion:

These results show that upregulation of the cell cycle and downregulation of Wnt signalling have an important role in osteosarcoma genesis. Gene expression differences between highly malignant osteosarcoma and benign osteoblastoma involve cell cycle regulation.

The Bt-DUX: development of a subjective measure of health-related quality of life in patients who underwent surgery for lower extremity malignant bone tumor

BACKGROUND

To examine the practical applicability, internal consistency, and validity of the Bt-DUX, a disease-specific Health Related Quality of Life (HRQoL) instrument. The Bt-Dux was developed to examine patients' individual values of their life after a malignant bone tumor of the lower extremity at four domains (cosmetic, social, emotional, and functional).

PROCEDURE

Patients were eligible for this cross-sectional, multicenter study if they underwent surgery for a malignant tumor of the leg in a period ranging between 12 and 60 months before the recruitment. Assessments included: Bt-DUX, Toronto Extremity Salvage Score (TESS) Short Form (SF)-36, TNO-AZL Questionnaire for Adult's Quality of Life (TAAQOL), and TNO-AZL Children's Quality of Life Questionnaire (TACQOL).

RESULTS

Seventy-two patients (35 male, 37 female), mean age 17 (SD 4) years were included. Limb sparing surgery took place in 32 patients and ablative surgery in 40 patients. The Bt-DUX was completed in less than 5 min and easy to comprehend. The mean Bt-DUX score was 69.8 (SD 15.5), with Cronbach's alpha being 0.92. Domain-total correlations ranged between 0.84 and 0.88 (P < 0.01). Correlations between Bt-DUX Total score and TESS, SF-36 Physical and Mental Component Summary scales and selected TACQOL and TAAQOL scores were statistically significant (P < 0.05), except for the social scale of the TACQOL. The Bt-DUX was able to discriminate between patients with higher and lower TESS scores (P < 0.05).

CONCLUSION

The Bt-DUX was found to be a practical and valid instrument. Its added value compared with existing HRQoL measures needs to be further established.

Kinome profiling of chondrosarcoma reveals SRC-pathway activity and dasatinib as option for treatment

Chondrosarcomas are notorious for their resistance to conventional chemotherapy and radiotherapy, indicating there are no curative treatment possibilities for patients with inoperable or metastatic disease. We therefore explored the existence of molecular targets for systemic treatment of chondrosarcoma using kinome profiling. Peptide array was performed for four chondrosarcoma cell lines and nine primary chondrosarcoma cultures with GIST882, MSCs, and colorectal cancer cell lines as controls. Activity of kinases was verified using immunoblot, and active Src- and platelet-derived growth factor receptor (PDGFR) signaling were further explored using imatinib and dasatinib on chondrosarcoma in vitro. The AKT1/GSK3B pathway was clearly active in chondrosarcoma. In addition, the PDGFR pathway and the Src kinase family were active. PDGFR and Src kinases can be inhibited by imatinib and dasatinib, respectively. Although imatinib did not show any effect on chondrosarcoma cell cultures, dasatinib showed a decrease in cell viability at nanomolar concentrations in seven of nine chondrosarcoma cultures. However, inhibition of phosphorylated Src (Y419) was found both in responsive and nonresponsive cells. In conclusion, using kinome profiling, we found the Src pathway to be active in chondrosarcoma. Moreover, we showed in vitro that the inhibitor of the Src pathway, dasatinib, may provide a potential therapeutic benefit for chondrosarcoma patients who are not eligible for surgery.

Reduced human leukocyte antigen expression in advanced-stage Ewing sarcoma: implications for immune recognition

Ewing sarcoma (EWS) is a tumour most commonly arising in bone, although on occasion in soft tissue, with a poor prognosis in patients with refractory or relapsed disease, despite multimodal therapy. Immunotherapeutic strategies based on tumour-reactive T and/or natural killer cells may improve the treatment of advanced-stage EWS. Since cellular immune recognition critically depends on human leukocyte antigen (HLA) expression, knowledge about HLA expression in EWS is crucial in the design of cellular immunotherapeutic strategies. Constitutive and IFNgamma-induced HLA class I expression was analysed in EWS cell lines (n = 6) by flow cytometry, using antibodies against both monomorphic and allele-specific antigens. Expression of antigen processing pathway components and beta-2 microglobulin (beta2m) was assessed by western blot. Expression of class II transactivator (CIITA), and its contribution to HLA class II expression, was evaluated by qRT-PCR, transduction assays, and flow cytometry. beta2m/HLA class I and class II expression was validated in EWS tumours (n = 67) by immunofluorescence. Complete or partial absence of HLA class I expression was observed in 79% of EWS tumours. Lung metastases consistently lacked HLA class I and sequential tumours demonstrated a tendency towards decreased expression upon disease progression. Together with absent or low constitutive expression levels of specific HLA class I loci and alleles, and differential induction of identical alleles by IFNgamma in different cell lines, these results may reflect the existence of an immune escape mechanism. Inducible expression of TAP-1/-2, tapasin, LMP-2/-7, and the beta2m/HLA class I complex by IFNgamma suggests that regulatory mechanisms are mainly responsible for heterogeneity in constitutive class I expression. EWSs lack IFNgamma-inducible HLA class II, due to lack of functional CIITA. The majority of EWS tumours, particularly if advanced-stage, exhibit complete or partial absence of both classes of HLA. This knowledge will be instrumental in the design of cellular immunotherapeutic strategies for advanced-stage EWS.

Aberrant heparan sulfate proteoglycan localization, despite normal exostosin, in central chondrosarcoma

The tumor suppressor genes EXT1 and EXT2 are involved in the formation of multiple osteochondromas, which can progress to become secondary peripheral chondrosarcomas. The most common chondrosarcoma subtype is primary central chondrosarcoma, which occurs in the medullar cavity of bone. The EXT1/EXT2 protein complex is involved in heparan sulfate proteoglycan (HSPG) biosynthesis, which is important for signal transduction of Indian hedgehog (IHH), WNT, and transforming growth factor (TGF)-beta. The role of EXT and its downstream targets in central chondrosarcomas is currently unknown. EXT1 and EXT2 were therefore evaluated in central chondrosarcomas at both the DNA and mRNA levels. Immunohistochemistry was used to assess HSPG (CD44v3 and SDC2), WNT (beta-catenin), and TGF-beta (PAI-1 and phosphorylated Smad2) signaling, whereas IHH signaling was studied both by quantitative polymerase chain reaction and in vitro. mRNA levels of both EXT1 and EXT2 were normal in central chondrosarcomas; genomic alterations were absent in these regions and in 30 other HSPG-related genes. Although HSPGs were aberrantly located (CD44v3 in the Golgi and SDC2 in cytoplasm and nucleus), this was not caused by mutation. WNT signaling negatively correlated with increasing histological grade, whereas TGF-beta positively correlated with increasing histological grade. IHH signaling was active, and inhibition decreased cell viability in one of six cell lines. Our data suggest that, despite normal EXT in central chondrosarcomas, HSPGs and HSPG-dependent signaling are affected in both central and peripheral chondrosarcomas.

Central chondrosarcoma progression is associated with pRb pathway alterations: CDK4 down-regulation and p16 overexpression inhibit cell growth in vitro

Chondrosarcomas are highly resistant to conventional radiation and chemotherapy, and surgical removal is the only option for curative treatment. Consequently, there is nothing to offer patients with inoperable tumours and metastatic disease. The aim of this study is to investigate genes involved in cell cycle control: CDK4, CDKN2A/p16, cyclin D1, p21, p53, MDM2 and c-MYC, which may point towards new therapeutic strategies. The pRb pathway was targeted using CDKN2A/p16 overexpressing vectors and shRNA against CDK4 in chondrosarcoma cell lines OUMS27, SW1353, and CH2879. Cell survival and proliferation were assessed. CDK4, MDM2 and c-MYC expression levels were investigated by qPCR and immunohistochemistry (IHC) in 34 fresh frozen and 90 FFPE samples of enchondroma and chondrosarcoma patients. On a subset of 29 high-grade chondrosarcomas IHC for cyclin D1, p21 and p53 was performed. The overexpression of CDKN2A/p16 and knockdown of CDK4 by shRNA in OUMS27, SW1353 and CH2879 resulted in a significant decrease in cell viability and proliferation and a decreased ability to form colonies in vitro. Expression of CDK4 and MDM2 was associated with high-grade chondrosarcoma both at the mRNA and protein level. Combining these results with the expression of cyclin D1 and the previously shown loss of CDKN2A/p16 expression show that the majority (96%; 28/29) of high-grade chondrosarcomas contain alterations in the pRb pathway. This suggests a role for the use of CDK4 inhibitors as a treatment of metastatic or inoperable high-grade chondrosarcoma.

The clinical approach towards chondrosarcoma

This review provides an overview of the histopathology, classification, diagnostic procedures, and therapy of skeletal chondrosarcoma. Chondrosarcomas that arise de novo are primary chondrosarcomas, whereas chondrosarcomas developing superimposed on pre-existing benign cartilage neoplasms such as enchondromas or osteochondromas are referred to as secondary chondrosarcomas. Conventional chondrosarcomas can be categorized according to their location in bone into central, peripheral, and juxtacortical chondrosarcomas. Histological grading is related to prognosis; however, it is also subject to interobserver variability. Rare subtypes of chondrosarcoma, including dedifferentiated, mesenchymal, and clear cell chondrosarcoma, are discussed as well. Magnetic resonance imaging is necessary to delineate the extent of the intraosseous and soft tissue involvement preoperatively. Computed tomography is especially recommended in the pelvis and other flat bones where it may be difficult to discern the pattern of bone destruction and the presence of matrix mineralization. Wide, en-bloc excision is the preferred surgical treatment in intermediate- and high-grade chondrosarcoma. In low-grade chondrosarcoma confined to the bone, extensive intralesional curettage followed by local adjuvant treatment and filling the cavity with bone graft has promising long-term clinical results and satisfactory local control. Chondrosarcomas are relatively radiotherapy resistant; therefore, doses >60 Gy are needed in attempts to achieve local control after incomplete resection. Irradiation with protons or other charged particles seems beneficial in this curative situation. Chemotherapy is only possibly effective in mesenchymal chondrosarcoma, and is of uncertain value in dedifferentiated chondrosarcoma. Potential new systemic treatment targets are being discussed.