The influence of tumor- and treatment-related factors on the development of local recurrence in osteosarcoma after adequate surgery. An analysis of 1355 patients treated on neoadjuvant Cooperative Osteosarcoma Study Group protocols

Establishment, Maintenance, and Performance of the Cooperative Osteosarcoma Study Group (COSS)

INTRODUCTION

Osteosarcoma treatment has benefitted greatly from collaborative research. This paper describes the history and accomplishments of the Cooperative Osteosarcoma Study Group (COSS), mainly dedicated to clinical questions, as well as remaining challenges.

MATERIALS AND METHODS

Narrative review of over four decades of uninterrupted collaboration within the multi-national German-Austrian-Swiss COSS group.

RESULTS

Since its very first prospective osteosarcoma trial starting in 1977, COSS has continuously been able to provide high-level evidence on various tumor- and treatment-related questions. This includes both the cohort of patients enrolled into prospective trials as well as those patients excluded from them for various reasons, followed in a prospective registry. Well over one hundred disease-related publications attest to the group's impact on the field. Despite these accomplishments, challenging problems remain.

DISCUSSION

Collaborative research within a multi-national study group resulted in better definitions of important aspects of the most common bone tumor, osteosarcoma, and its treatments. Important challenges continue to persist.

Osteosarcomas in older adults: A report from the Cooperative Osteosarcoma Study Group

INTRODUCTION

Osteosarcoma is typically a disease of the young, but may affect any age. Little is known about the disease in older patients beyond retirement age. We aim to describe the characteristics, treatment, and outcomes of older adult patients registered with our cooperative group.

MATERIALS AND METHODS

The database of the Cooperative Osteosarcoma Study Group (COSS) was searched for osteosarcoma patients diagnosed from 1980 to 2020 who were aged 65 years or older at diagnosis. Affected individuals were analyzed for presenting factors, treatments employed, and outcomes.

RESULTS

Fifty-five eligible patients were detected (median age 68 [range: 65-84] years; male:female = 25:30). Among these patients, 15/55 (27%) tumors were secondary malignancies, 41/55 (75%) were high-grade central, 4/55 (7%) surface, and 10/55 (18%) extraosseous malignancies, and all but three high-grade. Primary metastases were present in 15/55 (27%) patients. Surgery was reported for 46/55 (84%) patients, radiotherapy for 6/54 (11%, 1 unknown), chemotherapy for 42/50 (84%, 5 unknown). A complete surgical remission was achieved in 31/55 (56%). There were two toxic deaths. With a median follow-up of 1.7 (range: 0.1-18.0) years for all 55 patients and 2.2 (0.1-12.4) years for 24 survivors, event-free and overall survival at 2/5 years were 39.6% (standard error: 6.8%) / 24.5% (6.5%) and 62.0% (7.1%) / 32.7% (7.5%), respectively. Tumor site, metastatic status, surgery, and a complete surgical remission were prognostic for event-free and/or overall survival.

DISCUSSION

Osteosarcomas can occur in older individuals. It is more often secondary, axially located, or extraosseous than in younger patients. However, the same treatment principles seem to apply, and selected patients may be cured. Multi-center cooperation is encouraged, thereby gathering expertise for such a rare disease presentation.

Application of interpretable machine learning algorithms to predict distant metastasis in osteosarcoma

BACKGROUND

Osteosarcoma is well-established as the most common bone cancer in children and adolescents. Patients with localized disease have different prognoses and management than those with metastasis at the time of diagnosis. The purpose of this study was to explore potential risk factors for metastatic disease.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) Program database was used to identify patients diagnosed with osteosarcoma between 2004 and 2015. We developed prediction models for distant metastasis using six machine learning (ML) techniques, including logistic regression (LR), support vector machine (SVM), Gaussian Naive Bayes (GaussianNB), Extreme Gradient Boosting (XGBoost), random forest (RF), and k-nearest neighbor algorithm (kNN). The adaptive synthetic (ADASYN) technique was used to deal with imbalanced data. The Shapley Additive Explanation (SHAP) analysis generated visualized explanations for each patient. Finally, the average precision (AP), sensitivity, specificity, accuracy, F1 score, precision-recall curves, calibration plots, and decision curve analysis (DCA) were conducted to evaluate the models' effectiveness.

RESULTS

The six machine learning algorithms achieved AP of 0.661-0.781 for predicting distant metastasis. The RF model yielded the best performance with an accuracy of 71.8 percent and an AP of 0.781 and was highly dependent on tumor size, primary surgery, and age. SHAP analysis provided model-independent interpretation, highlighting significant clinical factors associated with the risk of metastasis in osteosarcoma patients.

CONCLUSIONS

An accurate machine learning-based prediction model was established for metastasis in osteosarcoma patients to help clinicians during clinical decision-making.

A classification system of joint-salvage tumor resection in osteosarcoma of the knee: A retrospective cohort study

BACKGROUND

Joint-preserving surgery is possible for patients with juxta-articular osteosarcoma of the knee, even when the tumor invades the epiphysis. Oncologic and functional outcomes may vary due to the extent of tumor invasion, the amount of epiphysis preservation, and reconstruction methods. We aimed to introduce a novel classification facilitating clinical evaluation of different surgical treatments.

METHODS

We identified 52 patients with osteosarcoma of the knee undergoing joint-preserving tumor resection and intercalary reconstruction. We classified procedures into two types and six subtypes based on the tumor location and adjuvant treatment employed. Oncologic outcomes, limb function and complications were compared among different types.

RESULTS

None of the patients had a local recurrence in the preserved epiphysis apart from three (5.7 %) who had local recurrence in soft tissue. Overall survival rate of the patients was 82.7 % at 5 and 10 years. There was no difference in survival rate (P = 0.909), local recurrence (P = 0.642) between type I (tumor not invading epiphysis) and type II (tumor invading epiphysis). In addition to one skin necrosis in the 3D-printed prosthesis reconstruction and one infection in Capanna reconstruction, all complications necessitating additional surgery occurred in allograft. The Musculoskeletal Tumor Society (MSTS) scores ranged from 21 to 30 with a median of 26. There were differences in the MSTS scores among six subgroups (P = 0.015), with the highest in type Ia and the lowest in type IIc. The less of the viable epiphysis retained, the worse the knee function was at long-term follow up.

CONCLUSIONS

The suggested classification can guide surgical strategy and is convenient for comparison of the functional results.

One-Dimensional Ferroelectric Nanoarrays with Wireless Switchable Static and Dynamic Electrical Stimulation for Selective Regulating Osteogenesis and Antiosteosarcoma

Preventing local tumor recurrence and simultaneously improving bone-tissue regeneration are in great demand for osteosarcoma therapy. However, the current therapeutic implants fail to selectively suppress tumor growth and enhance osteogenesis, and antitumor therapy may compromise osseointegration of the bone implant. Here, based on the different responses of bone tumor cells and osteoblasts to different electric stimulations, we constructed ferroelectric BaTiO₃ nanorod arrays (NBTO) on the surface of titanium implants with switchable dynamic and static electrical stimulation for selective bone-tumor therapy and bone tissue regeneration. Polarized NBTO (PNBTO) generated a sustained dynamic electrical stimulus in response to wireless ultrasonic irradiation ("switch-on"), which disrupted the orientation of the spindle filaments of the tumor cell, blocked the G2/M phase of mitosis, and ultimately led to tumor cell death, whereas it had almost no cytotoxic effect on normal bone cells. Under the switch-off state, PNBTO with a high surface potential provided static electrical stimulation, accelerating osteogenic differentiation of mesenchymal stem cells and enhancing the quality of bone regeneration both in vitro and in vivo. This study broadens the biomedical potential of electrical stimulation therapy and provides a comprehensive and clinically feasible strategy for the overall treatment and tissue regeneration in osteosarcoma.

Osteosarcoma pre-diagnosed as another tumor: a report from the Cooperative Osteosarcoma Study Group (COSS)

PURPOSE

The course of osteosarcoma patients primarily treated as such has been well described. Little, however, is known about patients who were primarily treated assuming a different tumor diagnosis.

METHODS

The database of the Cooperative Osteosarcoma Study Group COSS was searched (4.435 primary high-grade central osteosarcomas registered prior to 01/01/21). A different tumor entity had to have been assumed for at least one month after the initial diagnostic procedure before the correct diagnosis of osteosarcoma was finally made. Identified patients were analyzed for demographic, tumor-, and treatment-related factors as well as for survival outcomes.

RESULTS

37 patients were identified. They were a median of 19.7 (2.7-60.4) years old at first presentation and were more likely to be females than males (23:14). Bone cysts (n = 8), giant cell tumor of bone (n = 6), and osteoblastoma (n = 6) were the most frequent of 29/37 (78%) benign, chondrosarcoma and its variants (n = 6) the most frequent of 8/37 (22%) malignant original diagnoses. Tumors affected the extremities in 23 (62%), the trunk in 11 (30%), and the craniofacial bones in 3 (8%). Only one patient received systemic treatment while assuming the different diagnosis (1/37, 3%). The median time until the correct diagnosis of osteosarcoma was made was 8 months (range: 1 month-14.1 years). At that time, 6/37 (16%) presented with metastatic disease. All patients went on to receive chemotherapy, 17/37 (46%) neo-adjuvantly. Histologic response was only evaluated in 13/17 (76%) patients and was good (< 10% viable tumor) in only 4/13 (31%) patients. In 31/37 (84%) patients, a surgically complete resection of all macroscopically identified tumor manifestations could be achieved. Five-year overall and event-free survival rates at 5 years were 50.2% (standard error: 8.6%) and 42.6% (8.5%), respectively.

CONCLUSION

Osteosarcoma may initially be misdiagnosed and hence subjected to inappropriate treatment including misguided surgery. Once diagnosed correctly, some of the affected patients may still be cured if finally treated according to modern osteosarcoma standards.

Predictive value of the systemic immune-inflammation index for cancer-specific survival of osteosarcoma in children

Background

Osteosarcoma (OS) is the primary malignant bone tumor that most commonly affects children and adolescents. Recent years effective chemotherapy have improved the 5-year survival in osteosarcoma patients to up to 60%-70%. Still, there is a lack of novel therapeutic strategies to enhance further survival. Our study aimed to evaluate the clinical significance of pretreatment inflammatory-based parameters, including PLT, NLR, and SII, as prognostic indicators of survival in pediatric osteosarcoma patients.

Methods

A total of 86 pediatric osteosarcoma patients between 2012 and 2021 in the Department of Orthopedics or tumor Surgery of Children's Hospital affiliated to Chongqing Medical University were retrospectively analyzed. The clinicopathological variables and systematic inflammatory biomarkers, including NLR, PLR and SII, was performed by the A Receiver operating characteristic (ROC) curve and Cox proportional risk regression model. According to the results of multivariate analysis, a prognostic nomogram was generated, and the concordance index (C-index) was calculated to predict the performance of the established nomogram. The survival curve was plotted by the Kaplan-Meier method.

Results

Univariate analysis showed that TNM stage, tumor size, NLR value, PLR value, SII value, neutrophil count and platelet count were related to CSS (p < 0.05). According to multivariate analysis, only TNM stage (p = 0.006) and SII values (p = 0.015) were associated with poor prognosis.To further predict survival in pediatric osteosarcoma patients, multivariate Cox regression analysis was used to predict cancer-specific survival at 1, 3 and 5 years. And constructed a nomogram model to predict children's CSS. The C-index of the nomogram is 0.776 (95%CI, 0.776–0.910), indicating that the model has good accuracy.

Conclusion

Preoperative SII and TNM staging are independent prognostic markers for pediatric osteosarcoma patients. SII may be used in conjunction with TNM staging for individualized treatment of pediatric osteosarcoma patients in future clinical work.

Are Postoperative Infections in the First 12 Months after Wide Resection and Megaprosthetic Replacement Associated with the Survival of Osteosarcoma Patients? Results of a Multicenter Study

Simple Summary

Postoperative infection is one of the gravest complications in patients following megaprosthetic replacement due to primary malignant bone tumors. On the other hand, several studies have also suggested that patients with a variety of different cancers may have a better chance of survival following the development of an infection, possibly as a result of the immune and inflammatory host responses to infection. Our retrospective analysis of 437 extremity osteosarcoma patients found that patients with a poor response to neoadjuvant chemotherapy and an infection in the first 12 months after primary tumor surgery had a better chance of survival compared to patients without infections. If this finding can be validated in a different patient cohort, it would suggest that the efficacy of novel immunomodulatory treatments in osteosarcoma patients should be evaluated and reported separately for patients with a good and a poor response to preoperative chemotherapy, as the latter might benefit more from such treatments.

Abstract

Recent retrospective studies suggested that early postoperative infections might be associated with a survival benefit for extremity osteosarcoma patients, but the reported results have been conflicting. The files of 437 patients with a newly diagnosed, high-grade osteosarcoma of the extremities treated at 5 referral centers in Germany and Austria between 1989 and 2016 were retrospectively evaluated. All patients underwent multi-agent chemotherapy and limb-sparing tumor excision, followed by endoprothetic replacement. We used the Kaplan–Meier method to calculate survival curves, which we compared with the log-rank test. With a median follow-up of 100 months (interquartile range, 49–155 months), local recurrence (LR) probability, event-free survival (EFS), and disease-specific survival (DSS) after 5 years in this selected patient cohort amounted to 5%, 67%, and 79%, respectively, and 46 patients (10.5%) developed an early postoperative infection. We found no significant differences in LR, EFS, or DSS between patients with and without early infections, and there were no differences in known prognostic factors between the two groups. However, in subgroup analyses patients with a poor response to neoadjuvant chemotherapy and an early infection had a better DSS compared to patients without early infections (93% vs. 62% after 5 years, p = 0.044). Provided that our findings can be validated in separate patient cohorts, we believe that patient outcome after adjuvant immunomodulatory treatments in osteosarcoma patients should be evaluated and reported separately for good and poor responders to neoadjuvant chemotherapy in future studies.

Case Report: 3D-Printed Prosthesis for Limb Salvage and Joint Preservation After Tibial Sarcoma Resection

Introduction

Reconstruction of massive tibial defects in ankle joint-preserving surgery remains challenging though biological and prosthetic methods have been attempted. We surgically treated a patient with only 18-mm distal tibia remaining and reconstructed with a unique three-dimensional printed prosthesis.

Case Presentation, Intervention, and Outcomes

A 36-year-old male presented to our clinic with complaints of gradually swelling left calf and palpable painless mass for five months. Imageological exam indicated a lesion spanning the entire length of the tibia and surrounding the vascular plexus. Diagnosis of chondrosarcoma was confirmed by biopsy. Amputation was initially recommended but rejected, thus a novel one-step limb-salvage procedure was performed. After en-bloc tumor resection and blood supply rebuilding, a customized, three-dimensional printed prosthesis with porous interface was fixed that connected the tumor knee prosthesis and distal ultra-small bone segment. During a 16-month follow-up, no soft tissue or prosthesis-related complications occurred. The patient was alive with no sign of recurrence or metastasis. Walking ability and full tibiotalar range of motion were preserved.

Conclusions

Custom-made, three-dimensional printed prosthesis manifested excellent mechanical stability during the follow-up in this joint-preserving surgery. Further investigation of the durability and rate of long-term complications is needed to introduce to routine clinical practice.

SELNET clinical practice guidelines for bone sarcoma

Bone sarcoma are infrequent diseases, representing < 0.2% of all adult neoplasms. A multidisciplinary management within reference centers for sarcoma, with discussion of the diagnostic and therapeutic strategies within an expert multidisciplinary tumour board, is essential for these patients, given its heterogeneity and low frequency. This approach leads to an improvement in patient's outcome, as demonstrated in several studies. The Sarcoma European Latin-American Network (SELNET), aims to improve clinical outcome in sarcoma care, with a special focus in Latin-American countries. These Clinical Practice Guidelines (CPG) have been developed and agreed by a multidisciplinary expert group (including medical and radiation oncologist, surgical oncologist, orthopaedic surgeons, radiologist, pathologist, molecular biologist and representatives of patients advocacy groups) of the SELNET consortium, and are conceived to provide the standard approach to diagnosis, treatment and follow-up of bone sarcoma patients in the Latin-American context.

[Update on 3D printing in the surgery of musculoskeletal tumors]

The importance of 3D printing applications in the surgery of musculoskeletal tumors has increased in recent years. Even prior to the era of 3D printing, computer-assisted techniques, such as navigation, have proved their utility. Due to the variable appearance of bone tumors, there is a need for individual solutions. The 3D printing can be used for the development of anatomical demonstration models, the construction of patient-specific instruments and custom-made implants. For these three applications, different regulatory hurdles exist. Especially for the resection of pelvic tumors, 3D printing technologies seem to provide advantages due to the complicated anatomy and the proximity to relevant neurovascular structures. With the introduction of titanium printing, construction of individualized implants that fit exactly into the defect became feasible.

Prognostic factors and treatment of relapsed osteosarcoma: A monocentric Tunisian retrospective study

BACKGROUND

This study aimed to explore the treatment modalities of relapsed osteosarcoma, treatment results, and prognostic factors.

METHODS

We conducted a retrospective study of patients treated for relapsed osteosarcoma between 2005 and 2019. Patient survival was compared according to age, performance status, time to relapse, and surgical treatment at the relapse. Values of p<0.05 were considered to indicate statistical significance.

RESULTS

We included 49 patients who were treated for osteosarcoma. During the 13-year study period, 16 patients had relapsed osteosarcoma (32.7%). Prognostic factors of relapse were age over 18 years (p = 0.03), axial tumors (p = 0.01), and positive surgical margins (p = 0.018). Nine patients had palliative chemotherapy at the time of relapse. After a median follow-up of 8 months (range: 4-65 months), the overall survival at 1 year, 2 years, and 5 years after diagnosis of the relapse was 46.7%, 31.1%, and 20.7%, respectively. Relapsed osteosarcoma patients who had good performance status, late relapse (after 12 months), as well as surgery of the relapsed disease had better overall survival (OS).

CONCLUSION

Surgical treatment of relapsed osteosarcoma should be performed whenever possible since it improves significantly the survival of patients. Good performance status and late relapse were also associated with better survival.

Osteosarcoma: An Evolving Understanding of a Complex Disease

Osteosarcoma is the most common primary bone sarcoma and affects both children and adults. The cornerstone of treatment for patients with localized and oligometastatic disease remains neoadjuvant chemotherapy, surgical resection of all sites of disease, followed by adjuvant chemotherapy. This approach is associated with up to an 80% 5-year survival. However, survival of patients with metastatic disease remains poor, and overall, osteosarcoma remains a challenging disease to treat. Advances in the understanding of molecular drivers of the disease, identification of poor prognostic factors, development of risk-stratified treatment protocols, successful completion of large collaborative trials, and surgical advances have laid the ground work for progress. Advances in computer navigation, implant design, and surgical techniques have allowed surgeons to improve patients' physical functional without sacrificing oncologic outcomes. Future goals include identifying effective risk stratification algorithms which minimize patient toxicity while maximizing oncologic outcomes and continuing to improve the durability, function, and patient acceptance of oncologic reconstructions.

Bone sarcoma: success through interdisciplinary collaboration

PURPOSE

Osteosarcoma and Ewing sarcoma are the most frequent malignant bone tumours of childhood and adolescence. This review summarizes the oncologist's view of these diseases and their treatment.

METHODS

A non-systematic literature review was performed, the personal impressions and experience of the authors is described.

RESULTS

Local therapy and chemotherapy, each on their own, will not cure patients with malignant bone sarcomas. Together, they present a highly efficacious combination. While the most effective drugs were defined decades ago, progress since then has been limited. It is hoped that substances shown to be active in relapsed disease will be forwarded into even more efficacious frontline treatments. Good palliative therapy is necessary when cure is no longer an option.

CONCLUSION

Close interdisciplinary collaboration is the key to successful treatment of bone sarcomas in paediatric patients.

Complex joint-preserving bone tumor resection and reconstruction using computer navigation and 3D-printed patient-specific guides: A technical note of three cases

In selected extremity bone sarcomas, joint-preserving surgery retains the natural joints and nearby ligaments with a better function than in traditional joint-sacrificing surgery. Geometric multiplanar osteotomies around bone sarcomas were reported with the advantage of preserving more host bone. However, the complex surgical planning translation to the operating room is challenging.

Using both Computer Navigation and Patient-Specific Guide may combine each technique's key advantage in assisting complex bone tumor resections. Computer Navigation provides the visual image feedback of the pathological information and validates the correct placement of Patient-Specific Guide that enables accurate, guided bone resections. We first described the digital workflow and the use of both computer navigation and patient-specific guides (NAVIG) to assist the multiplanar osteotomies in three extremity bone sarcoma patients who underwent joint-preserving bone tumor resections and reconstruction with patient-specific implants. The NAVIG technique verified the correct placement of patient-specific guides that enabled precise osteotomies and well-fitted patient-specific implants. The mean maximum deviation errors of the nine achieved bone resections were 1.64 ​± ​0.35 ​mm (95% CI 1.29 to 1.99). The histological examination of the tumor specimens showed negative resection margin. At the mean follow-up of 55 months (40–67), no local recurrence was noted. There was no implant loosening that needed revision. The mean MSTS score was 29 (28–30) out of 30 with the mean knee flexion of 140° (130°–150°).

The excellent surgical accuracy and limb function suggested that the NAVIG technique might replicate the surgical planning of complex bone sarcoma resections by combining the strength of both Computer Navigation and Patient-Specific Guide. The patient-specific approach may translate into clinical benefits. The translational potential of this article:

The newly described technique enhances surgeons’ capability in performing complex joint-preserving surgery in bone sarcoma that is difficult to be achieved by the traditional method. The high precision and accuracy may translate into superior clinical outcomes.

Precision medicine in pediatric solid cancers

Despite huge advances in the diagnosis and treatment of pediatric cancers over the past several decades, it remains one of the leading causes of death during childhood in developed countries. The development of new targeted treatments for these diseases has been hampered by two major factors. First, the extremely heterogeneous nature of the types of tumors encountered in this age group, and their fundamental differences from common adult carcinomas, has made it hard to truly get a handle on the complexities of the underlying biology driving tumor growth. Second, a reluctance of the pharmaceutical industry to develop products or trials for this population due to the relatively small size of the 'market', and a too-easy mechanism of obtaining waivers for pediatric development of adult oncology drugs based on disease type rather than mechanism of action, led to significant difficulties in getting access to new drugs. Thankfully, the field has now started to change, both scientifically and from a regulatory perspective, in order to address some of these challenges. In this review, we will examine some of the recent insights into molecular features which make pediatric tumors so unique and how these might represent therapeutic targets; highlight ongoing international initiatives for providing comprehensive, personalized genomic profiling of childhood tumors in a clinically-relevant timeframe, and look briefly at where the field of pediatric precision oncology may be heading in future.

Osteosarcoma

Osteosarcoma is a rare tumor that requires complex multidisciplinary management. This paper reviews the general management and standard radiotherapy guidelines for osteosarcoma in both North America and Europe in a joined effort between the Children's Oncology Group and International Society of Pediatric Oncology. Standard treatment involves multiagent induction chemotherapy followed by surgical resection for local tumor control and consolidation local control to metastatic sites. Radiotherapy is reserved for cases with a marginal or incomplete resection or for definitive treatment in the case of unresectable disease. We present supporting data for the role of chemotherapy, surgery, and radiation therapy.

Construction and validation of nomogram to predict distant metastasis in osteosarcoma: a retrospective study

Background

Osteosarcoma is most common malignant bone tumors. OS patients with metastasis have a poor prognosis. There are few tools to assess metastasis; we want to establish a nomogram to evaluate metastasis of osteosarcoma.

Methods

Data from the Surveillance, Epidemiology, and End Results (SEER) database of patients with osteosarcoma were retrieved for retrospective analysis. We identify risk factors through univariate logistic regression and multivariate logistic regression analysis. Based on the results of multivariate analysis, we established a nomogram to predict metastasis of patients with osteosarcoma and used the concordance index (C-index) and calibration curves to test models.

Results

One thousand fifteen cases were obtained from the SEER database. In the univariate and multivariate logistic regression analysis, age, primary site, grade, T stage, and surgery are risk factors. The nomogram for metastasis was constructed based on these factors. The C-index of the training and validation cohort was 0.754 and 0.716. This means that the nomogram predictions of patients with metastasis are correct, and the calibration plots also show the good prediction performance of the nomogram.

Conclusion

We successfully develop the nomogram which can reliably predict metastasis in different patients with osteosarcoma and it only required basic information of patients. The nomogram that we developed can help clinicians better predict the metastasis with OS and determine postoperative treatment strategies.

Relative Sensitivity of Core-Needle Biopsy and Incisional Biopsy in the Diagnosis of Musculoskeletal Sarcomas

BACKGROUND

There is no evidence as to the diagnostic value of the two most frequently used methods of biopsies in sarcomas: Incisional or core needle biopsy. The aim of our study was to evaluate the diagnostic sensitivity of the incisional and the core needle biopsy techniques in the diagnosis of bone and soft tissue sarcomas.

METHODS

We included 417 patients with a definitive diagnosis of bone or soft tissue sarcoma in whom a total of 472 biopsies had been performed. We correlated the results of the biopsies with the result of the definitive histopathological examination of the resected tumor. Dignity, entity, and grading (whenever possible) of the tissue samples were evaluated.

RESULTS

A total of 258 biopsies (55%) were performed in order to diagnose a soft tissue tumor and 351 biopsies (74.4%) were core needle biopsies. The number of repeat core needle biopsies, necessitated because of inconclusive histopathological results, was significantly higher (50 vs. 5; p = 0.003). We observed no significant difference regarding dignity, entity, and grading between the 2 different types of biopsies. Only with regards to the determination of dignity and entity of chondroid tumors, incisional biopsy was superior with statistical significance (p = 0.024).

CONCLUSIONS

This study represents the largest study on biopsies for bone and soft tissue sarcomas. Based only on our results, we are unable to favor one method of biopsy and found high accuracy with both methods. Considering the potential complications, the added oncological risks of incisional biopsies and the ready availability of core needle biopsies, the latter, in our assessment, represents a valid and favourable method for bone and soft tissue sarcomas.

Computer Navigation and 3D Printing in the Surgical Management of Bone Sarcoma

The long-term outcomes of osteosarcoma have improved; however, patients with metastases, recurrence or axial disease continue to have a poor prognosis. Computer navigation in surgery is becoming ever more commonplace, and the proposed advantages, including precision during surgery, is particularly applicable to the field of orthopaedic oncology and challenging areas such as the axial skeleton. Within this article, we provide an overview of the field of computer navigation and computer-assisted tumour surgery (CATS), in particular its relevance to the surgical management of osteosarcoma.

Proximal femur sarcomas with intra-articular disease-Do intra-articular resections provide adequate local control?

BACKGROUND AND OBJECTIVES

Hip preserving (intra-articular) resections for proximal femur sarcoma have better function compared to peri-acetabular (extra-articular) resections, which are more complex and morbid. But, do intra-articular resections in selected cases with intra-articular disease provide adequate local control?

METHOD

Extra-articular resection or intra-articular resection in cases without pathologic fracture or away from joint/capsule was classified as a planned safe margin (SM). Circumferential removal of labrum without acetabular resection in cases without gross joint contamination was classified as planned close margins (CM). We analyzed local recurrence-free survival (LRFS) (death as a competing event) for 86 proximal femur resections (SM = 55, CM = 31).

RESULTS

The 5 years LRFS was 84% (n = 6/55, 10%) in the SM group and 67% (n = 4/31, 12%) in the CM group. There was no worsening of local recurrence (LR) in the CM group (subdistribution hazard [sH] = 0.69; 95% confidence interval [CI], 0.21-2.29; P = .56). Poor chemotherapy-induced necrosis predicted worse LR (sH = 0.1; 95% CI, 0.01-0.8; P = .03). Overall survival was 16% (SE 8%) at 5 years with LR vs 64% (SE 7%) without LR (P = .0076).

CONCLUSION

In proximal femur sarcomas with potential for involvement of the hip joint, a CM in selected cases did not worsen LR; providing an option for avoiding additional morbidity with extra-articular resections.

Guideline for Limb-Salvage Treatment of Osteosarcoma

Osteosarcoma is the most common primary malignant bone tumor, occurring mainly in children and adolescents, and the limbs are the main affected sites. At present, limb‐salvage treatment is considered as an effective basic standard treatment for osteosarcoma of the limb. China has a vast territory, but the development of technology is not balanced,which requires sufficient theoretical coverage, strong technical guidance and the application of limb‐salvage treatment guidelines to the treatment of osteosarcoma. Therefore, to standardize and promote the development of limb‐salvage surgery technology and improve the success rate of limb‐salvage treatment, this guide systematically introduces limb‐salvage techniques for the treatment of patients with limb osteosarcoma through definition of limb‐salvage treatment, surgical methods, efficacy evaluation, postoperative treatment and prevention of complications, rehabilitation guidance, and follow‐up advice.

Pelvic bone tumor resection: what a radiologist needs to know

Pelvic bone tumors present a diagnostic and therapeutic challenge. Due to the deep anatomic location and resultant late clinical presentation, pelvic bone tumors tend to be large and located in close proximity to pelvic viscera as well as vital neurovascular structures. Operative management of pelvic bone tumors is indicated for a variety of orthopedic oncologic conditions. In general, limb-sparing pelvic resection rather than hemipelvectomy with amputation of the ipsilateral limb is considered when a functional limb can be preserved without compromising the surgical margins. There are various options for pelvic resection and reconstruction, and the selection depends on tumor histology, anatomic location, and extent. The decision regarding choice of surgical procedure and reconstruction method for a pelvic bone tumor requires a thorough knowledge of the pelvic anatomy, and careful inspection of the anatomic extent. The surgical plan must strike a balance between acceptable functional outcome and acceptable morbidity. In this review, we describe the different types of pelvic resection techniques, and the vital role preoperative imaging plays in defining the anatomic extent of a pelvic bone tumor and subsequent surgical planning.

Buformin suppresses osteosarcoma via targeting AMPK signaling pathway

BACKGROUND

Buformin has been reported to be a powerful anticancer drug by activating the AMPK signal. Herein, we aimed to investigate the effects of buformin on osteosarcoma.

MATERIAL AND METHODS

Cellular proliferative abilities were determined by cell counting kit-8 and colony formation assays. Cellular invasion was investigated using a transwell system. Cell cycle was examined by flow cytometry. Western blot was performed to measure the expression of key proteins. Synergistic effects of buformin and cisplatin were validated in seven fresh osteosarcoma tissues.

RESULTS

Buformin suppressed the growth of U-2 OS cells in a dose-dependent manner (IC50 = 69.1 µM). Moreover, buformin induced cell cycle arrest (P < 0.001) and impaired cellular invasion (P = 0.038). Phosphorylation of AMPK was upregulated by buformin, while phosphorylation of S6, cyclin D1, and MMP9 were significantly downregulated. In addition, buformin notably induced accumulation of reactive oxygen species and lactate and eventually decreased ATP production. In both U-2 OS cells and the primary cultured osteosarcoma tissues, buformin increased tumor sensitivity to cisplatin.

CONCLUSIONS

Buformin could suppress tumor growth and invasion of osteosarcoma through directly targeting the AMPK signaling pathway. Moreover, buformin inhibited the abnormal metabolism and notably increased the cytotoxicity of cisplatin, and therefore represents a new potential treatment option for osteosarcoma.

Clinical Prognostic Factors and Outcome in Pediatric Osteosarcoma: Effect of Delay in Local Control and Degree of Necrosis in a Multidisciplinary Setting in Lebanon

PURPOSE

Outcomes in pediatric osteosarcoma have dramatically improved over the past few decades, with overall survival rates of 70% and 30% for patients with localized and metastatic disease, respectively.

PATIENTS AND METHODS

We retrospectively reviewed clinical characteristics and outcomes of 38 patients treated between 2001 and 2012 at a single institution in Lebanon. All patients received a uniform three-drug chemotherapy regimen consisting of cisplatin, doxorubicin, and methotrexate. Ifosfamide and etoposide were added to the adjuvant treatment regimen in case of metastatic disease and/or poor degree of tumor necrosis (< 90%).

RESULTS

After a median follow-up of 61 months (range, 8 to 142 months), patients with localized disease had 5-year overall and event-free survival rates of approximately 81% and 68%, respectively, whereas for metastatic disease, they were approximately 42%. The most common primary site was the long bones around the knee (n = 34; 89.5%). Six patients (15.8%) had metastatic disease to lungs, and three (7.9%) had synchronous multifocal bone disease with lung metastases. Adverse prognostic factors included nonlower extremity sites, metastasis, poor degree of necrosis, and delay of more than 4 weeks in local control. In bivariable analysis, only degree of necrosis was a prognostic predictor for survival and disease recurrence.

CONCLUSION

Treatment of pediatric osteosarcoma in a multidisciplinary cancer center in Lebanon resulted in survival similar to that in developed countries. Delay in local control was associated with worse outcome. The only statistically significant inferior outcome predictor was poor degree of necrosis at the time of local control.

Malignant tumours of the foot and ankle

Tumours of the foot and ankle constitute about 4-5% of all musculoskeletal tumours with the majority of them being benign. Diagnosis of malignant soft tissue or bone tumours is frequently delayed because of the relatively low prevalence and uncommon presentation at the foot and ankle. Suspicious lesions or lumps should be subjected to CT, MRI and biopsy. Subfascial location, lump size more than 5 cm, increase in size, painful and recurrent tumours should raise the suspicion of malignancy and lead to patient referral to a designated tumour centre. Neoadjuvant and adjuvant systemic chemotherapy and/or radiation therapy, isolated limb perfusion (ILP) and hyperthermia for malignant tumours have to be discussed in a multidisciplinary tumour board. With the advances in local and free tissue transfer, limb-sparing techniques have increasingly replaced primary amputations thus preserving lower limb function as much as possible without compromising on the principles of oncologic resection.

Prognostic Factors for Development of Subsequent Metastases in Localized Osteosarcoma: A Systematic Review and Identification of Literature Gaps

Aim

To investigate prognostic factors in pediatric and young adult patients with localized osteosarcoma that could predict the development of subsequent pulmonary metastases and lead to an ability to risk-stratify therapy. We performed a systematic review of the literature published since January 1990 to establish common evidence-based prognostic factors.

Methods

PubMed and Embase searches (Jan 1990–Aug 2018) were performed. Two reviewers independently selected papers for patients with localized osteosarcoma with subsequent metastatic development and then reviewed for quality of methods and prognostic factors.

Results

Database searches yielded 216 unique results. After screening, 27 full-text articles were studied in depth, with 9 items fulfilling predetermined inclusion and exclusion criteria. Age, tumor location, tumor size/volume, and histologic response carried independent prognostic value in the majority of the studies.

Conclusions

Several prognostic factors seemed to be consistent amongst the studies, but the heterogeneity and smaller sizes of the study populations made pooling of results difficult. Standardization of larger patient populations and consistent definitions/cutoffs for prognostic factors are needed to further assess for consistent prognostic factors and potential predictive models to be developed.

Joint-preservation surgery for pediatric osteosarcoma of the knee joint

The multi-disciplinary approach involving imaging, multi-agent chemotherapy, meticulous surgical procedures, and careful postoperative care has facilitated an increase in the use of limb-sparing surgery for pediatric osteosarcoma. Osteosarcoma usually occurs around the metaphysis of the distal femur or proximal tibia and needs wide excision with the adjacent joint and replacement by a megaprosthesis. The recent advancement in imaging modalities and surgical techniques supports joint-preservation surgery (JPS), involving the preservation of the adjacent epiphysis, for select patients following careful assessment of the tumor margins and precise tumor excision. An advantage of this surgery is that it maintains the adjacent joint and preserves the growth of the residual epiphysis, which provides excellent limb function. Various reconstruction options are available, including allograft, tumor-devitalized autograft, vascularized fibula graft, distraction osteogenesis, and custom-made implants. However, several complications are inevitable with these options, such as loosening, non-union at the host-graft junction, infection, fracture, implant loosening, breakage, deformity, limb-length discrepancy related to the reconstruction methods, or patient growth in pediatric osteosarcoma. Surgeons should fully understand the advantages and disadvantages of this procedure. In this review, we discuss the concept of JPS, types of reconstruction methods, and current treatment outcomes. It is our opinion that the further analysis by multi-institutional setting is necessary to clarify long-term outcomes and establish global guidelines on the indications and surgical procedure for JPS.

Which Factors Are Associated with Local Control and Survival of Patients with Localized Pelvic Ewing's Sarcoma? A Retrospective Analysis of Data from the Euro-EWING99 Trial

BACKGROUND

Local treatment of pelvic Ewing's sarcoma may be challenging, and intergroup studies have focused on improving systemic treatments rather than prospectively evaluating aspects of local tumor control. The Euro-EWING99 trial provided a substantial number of patients with localized pelvic tumors treated with the same chemotherapy protocol. Because local control included surgical resection, radiation therapy, or a combination of both, we wanted to investigate local control and survival with respect to the local modality in this study cohort.

QUESTIONS/PURPOSES

(1) Do patients with localized sacral tumors have a lower risk of local recurrence and higher survival compared with patients with localized tumors of the innominate bones? (2) Is the local treatment modality associated with local control and survival in patients with sacral and nonsacral tumors? (3) Which local tumor- and treatment-related factors, such as response to neoadjuvant chemotherapy, institution where the biopsy was performed, and surgical complications, are associated with local recurrence and patient survival in nonsacral tumors? (4) Which factors, such as persistent extraosseous tumor growth after chemotherapy or extent of bony resection, are independently associated with overall survival in patients with bone tumors undergoing surgical treatment?

METHODS

Between 1998 and 2009, 1411 patients with previously untreated, histologically confirmed Ewing's sarcoma were registered in the German Society for Pediatric Oncology and Hematology Ewing's sarcoma database and treated in the Euro-EWING99 trial. In all, 24% (339 of 1411) of these patients presented with a pelvic primary sarcoma, 47% (159 of 339) of which had macroscopic metastases at diagnosis and were excluded from this analysis. The data from the remaining 180 patients were reviewed retrospectively, based on follow-up data as of July 2016. The median (range) follow-up was 54 months (5 to 191) for all patients and 84 months (11 to 191) for surviving patients. The study endpoints were overall survival, local recurrence and event-free survival probability, which were calculated with the Kaplan-Meier method and compared using the log-rank test. Hazard ratios (HRs) with their respective 95% CIs were estimated in a multivariate Cox regression model.

RESULTS

Sacral tumors were associated with a reduced probability of local recurrence (12% [95% CI 1 to 22] versus 28% [95% CI 20 to 36] at 5 years, p = 0.032), a higher event-free survival probability (66% [95% CI 51 to 81] versus 50% [95% CI 41 to 58] at 5 years, p = 0.026) and a higher overall survival probability (72% [95% CI 57 to 87] versus 56% [95% CI 47 to 64] at 5 years, p = 0.025) compared with nonsacral tumors. With the numbers available, we found no differences between patients with sacral tumors who underwent definitive radiotherapy and those who underwent combined surgery and radiotherapy in terms of local recurrence (17% [95% CI 0 to 34] versus 0% [95% CI 0 to 20] at 5 years, p = 0.125) and overall survival probability (73% [95% CI 52 to 94] versus 78% [95% CI 56 to 99] at 5 years, p = 0.764). In nonsacral tumors, combined local treatment was associated with a lower local recurrence probability (14% [95% CI 5 to 23] versus 33% [95% CI 19 to 47] at 5 years, p = 0.015) and a higher overall survival probability (72% [95% CI 61 to 83] versus 47% [95% CI 33 to 62] at 5 years, p = 0.024) compared with surgery alone. Even in a subgroup of patients with wide surgical margins and a good histologic response to induction treatment, the combined local treatment was associated with a higher overall survival probability (87% [95% CI 74 to 100] versus 51% [95% CI 33 to 69] at 5 years, p = 0.009), compared with surgery alone.A poor histologic response to induction chemotherapy in nonsacral tumors (39% [95% CI 19 to 59] versus 64% [95% CI 52 to 76] at 5 years, p = 0.014) and the development of surgical complications after tumor resection (35% [95% CI 11 to 59] versus 68% [95% CI 58 to 78] at 5 years, p = 0.004) were associated with a lower overall survival probability in nonsacral tumors, while a tumor biopsy performed at the same institution where the tumor resection was performed was associated with lower local recurrence probability (14% [95% CI 4 to 24] versus 32% [95% CI 16 to 48] at 5 years, p = 0.035), respectively.In patients with bone tumors who underwent surgical treatment, we found that after controlling for tumor localization in the pelvis, tumor volume, and surgical margin status, patients who did not undergo complete (defined as a Type I/II resection for iliac bone tumors, a Type II/III resection for pubic bone and ischium tumors and a Type I/II/III resection for tumors involving the acetabulum, according to the Enneking classification) removal of the affected bone (HR 5.04 [95% CI 2.07 to 12.24]; p < 0.001), patients with a poor histologic response to induction chemotherapy (HR 3.72 [95% CI 1.51 to 9.21]; p = 0.004), and patients who did not receive additional radiotherapy (HR 4.34 [95% CI 1.71 to 11.05]; p = 0.002) had a higher risk of death. The analysis suggested that the same might be the case in patients with a persistent extraosseous tumor extension after induction chemotherapy (HR 4.61 [95% CI 1.03 to 20.67]; p = 0.046), although the wide CIs pointing at a possible sparse-data bias precluded any definitive conclusions.

CONCLUSION

Patients with sacral Ewing's sarcoma appear to have a lower probability for local recurrence and a higher overall survival probability compared with patients with tumors of the innominate bones. Our results seem to support a recent recommendation of the Scandinavian Sarcoma Group to locally treat most sacral Ewing's sarcomas with definitive radiotherapy. Combined surgical resection and radiotherapy appear to be associated with a higher overall survival probability in nonsacral tumors compared with surgery alone, even in patients with a wide resection and a good histologic response to neoadjuvant chemotherapy. Complete removal of the involved bone, as defined above, in patients with nonsacral tumors may be associated with a decreased likelihood of local recurrence and improved overall survival. Persistent extraosseous tumor growth after induction treatment in patients with nonsacral bone tumors undergoing surgical treatment might be an important indicator of poorer overall survival probability, but the possibility of sparse-data bias in our cohort means that this factor should first be validated in future studies.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Anti-osteosarcoma effect of hydroxyapatite nanoparticles both in vitro and in vivo by downregulating the FAK/PI3K/Akt signaling pathway

Schematic representing the anti-cancer effects of nano-HAPs both in vitro and in vivo by downregulating the FAK/PI3K/Akt signaling pathway.

Application of hydroxyapatite nanoparticles in tumor-associated bone segmental defect

Hydroxyapatite (HA) has been widely applied in bone repair because of its superior biocompatibility. Recently, a proliferation-suppressive effect of HA nanoparticles (n-HA) against various cancer cells was reported. This study was aimed at assessing the translational value of n-HA both as a bone-regenerating material and as an antitumor agent. Inhibition of tumor growth, prevention of metastasis, and enhancement of the survival rate of tumor-bearing rabbits treated with n-HA were demonstrated. Activated mitochondrial-dependent apoptosis in vivo was confirmed, and we observed that a stimulated immune response was involved in the n-HA-induced antitumor effect. A porous titanium scaffold loaded with n-HA was fabricated and implanted into a critical-sized segmental bone defect in a rabbit tumor model. The n-HA-releasing scaffold not only showed a prominent effect in suppressing tumor growth and osteolytic lesion but also promoted bone regeneration. These findings provide a rationale for using n-HA in tumor-associated bone segmental defects.

Preservation of the Epiphysis and Growth Plate in the Surgical Management of Femoral Osteosarcoma in a Skeletally Immature Patient by Intercalary Resection and Biological Reconstruction: A Case Report

Osteosarcoma arises most frequently in the metaphysis around the knee and its management by limb salvage surgery in skeletally immature pediatric patients is extremely challenging. Common reconstructive methods such as endoprosthetic or biological reconstruction are not fully capable of dealing with durability-related and growth-related problems and their functional outcomes are not as good as those seen in adult cases. A definitive limb salvaging procedure in children that outperforms amputation or rotationplasty has not yet been established. Herein, we report a case of stage IV osteosarcoma in the femur of a 7-year-old boy that was safely managed with intercalary resection preserving the distal femoral growth plate and epiphysis, followed by biological reconstruction using a frozen tumor-devitalized autograft. Good response to preoperative chemotherapy and the diaphyseal location of the tumor enabled us to perform a tumor resection that spared the growth plate and preserved the native knee joint structure. Plate fixation over the growth plate was terminated by removing the locking screws in the epiphysis after 44 months, which restored growth capacity to some extent. At 50 months postoperatively, no recurrence or progression of the disease was observed. The patient uses an extension shoe and reports having little discomfort in his daily life despite having a restricted range of motion and limb length discrepancy. In conclusion, limb salvage with biological reconstruction in skeletally immature patients can provide an acceptable functional outcome, including minimized limb length discrepancy, if critical damage to the growth plate and articular components can be avoided.

The History of Bone Tumour Treatment and the State of the Art in Vienna

PURPOSES

Bone tumours have been a tragedy for the patient in any time period. In the majority of the cases it occurs in children or young adults. In the past the affected limbs could not be spared and the overall prognosis was poor.

METHODS

Chemotherapy successfully introduced for the purpose of overcoming the poor overall prognosis (Rosen and Jaffe) and tumour prostheses were invented for the purpose of salvaging the affected limbs (Marcove, Scales, Campanacci, Sivas, Salzer). According to the Vienna Tumour Registry in 1968, the first custom-made Vitallium prosthesis for the proximal femur was implanted in a parosteal osteosarcoma.

RESULTS

In Vienna, as a result of the successful chemotherapy the surgical methods for bone tumours changed to limb sparing methods also. A modular ceramic prosthesis for the proximal humerus was introduced by Salzer. From 1975 -1982 16 custom-made endoprosthesis (1) for the knee region were implanted which were replaced by the KMFTR in 1982 (2, Kotz modular femur tibia reconstruction system) which was introduced at the "2nd ISOLS" to an international group of experts. The successful system was followed by the HMRS (Howmedica modular resection system) in 1988. At that time, especially in children, the rotation-plasty of Borgreve was adopted for tumours of the knee region (2). A scientific survey of 70 patients with rotation-plasty until 1991 showed excellent clinical and oncologic results. Later a similar approach was used in upper extremity tumours as "resection replantation" with surprisingly good results. Sophisticated technologies with growing mechanisms allowed the use of endoprostheses even in children (3) for the purpose of substitution since the mutilating rotation-plasty in 1996.

CONCLUSION

For almost 100 years efforts have been undertaken to improve the treatment of bone tumours. Surgery was aiming to keep the function of the limbs by tumour resection instead of amputation. Together with successful chemotherapy, which saves lives, an adequate surgery could stepwise salvage the function of the limb. Body integrity was the final aim for the diseased. Finally, by the effort of the International Societies like ISOLS and EMSOS the survival of malignant bone tumour patients improved from 20% to 80 % with good function quality by sophisticated operative techniques and improved tumour prostheses.

Treatment-Related Prognostic Factors in Managing Osteosarcoma around the Knee with Limb Salvage Surgery: A Lesson from a Long-Term Follow-Up Study

Purpose

The aim of this study was to assess the treatment-related factors associated with local recurrence and overall survival of patients with osteosarcoma treated with limb-salvage surgery.

Patients and Methods

Treatment-related factors were analyzed to evaluate their effects on local recurrence-free survival (LRFS) and overall survival (OS) in 182 patients from 2004 to 2013.

Results

The mean length of follow-up was 73.4 ± 34.7 months (median, 68 months; range, 12-173 months), and 63 patients died by the end of the follow-up. The 5-year and 10-year overall survival rates were 68.6 ± 6.6% and 59.4 ± 10.6%, respectively. Univariate analysis showed that treatment-related prognostic factors for overall survival were prolonged symptom intervals >=60 days, biopsy/tumor resection performed by different centers, previous medical history, incomplete preoperative chemotherapy (<8 weeks), and prolonged postoperative interval >21 days. In the multivariate analysis, biopsy/tumor resection performed by different centers, incomplete implementation of planned new adjuvant chemotherapy, and delayed resumption of postoperative chemotherapy (>21 days) were risk factors for poor prognosis; biopsy/tumor resection performed by different centers and tumor necrosis <90% were independent predictors of local recurrence.

Conclusion

For localized osteosarcoma treated with limb-salvage surgery, it is necessary to optimize timely standard chemotherapy and to resume postoperative chemotherapy to improve survival rates. Biopsies should be performed at experienced institutions in cases of developing local recurrence.

Megaprosthetic replacement of the distal humerus: still a challenge in limb salvage

BACKGROUND

The distal humerus is a rare location of bone tumors. Because of the complexity of the elbow joint, poor soft-tissue coverage, and proximity of nerves and vessels, resection and endoprosthetic reconstruction are demanding.

METHODS

This retrospective study evaluated the clinical results after distal humeral resection and megaprosthetic reconstruction in 12 patients with an average age of 46 years. All patient files were reviewed for clinical information, and postoperative function and patients' contentment were assessed using the Musculoskeletal Tumor Society score.

RESULTS

The predominant diagnoses were bone and soft-tissue sarcoma (n = 6), giant cell tumor (n = 2), and renal cell carcinoma metastasis (n = 2). Local recurrence was the reason for secondary amputation in all cases (n = 3). The prosthetic survival rate after surgery was 82% at 2 years and 64% at 5 years. Reconstruction failure was mainly caused by aseptic loosening of the humeral stem, occurring in 27% (n = 3), followed by aseptic loosening of the ulnar stem in 9% (n = 1) and periprosthetic infection in 9% (n = 1). The mean Musculoskeletal Tumor Society score was 24 points (range, 20-30 points). An extension lag of more than 10° was noted in 6 patients (55%).

CONCLUSION

Our results suggest that limb salvage with a distal humeral replacement can achieve good functional results in most patients, although the complication rate with special emphasis on the loosening rate of the humeral stem is high. However, limb salvage was not achieved in 27% of patients because of local recurrence.

Pre-Operative chemotherapy response assessed by contrast-enhanced MRI can predict the prognosis of Enneking surgical margins in patients with osteosarcoma

The method used to evaluate the response of osteosarcoma to preoperative chemotherapy before specimen resection is still unclear. The purpose of this study was to identify factors that contribute to overall survival (OS) and to discuss their roles in making a decision regarding Enneking surgical margins. Patients (109) with pathologically confirmed Enneking stage IIB osteosarcoma were retrospectively analyzed. Univariate and multivariate survival analyses were performed. Patient characteristics and chemotherapy-induced contrast-enhanced MRI changes were considered as potential factors. Changes in the tumor volume and the relative necrosis ratio measured by MRI were independent risk factors predicting the OS of patients who underwent limb-salvage surgery. For those in whom the tumor volume had decreased (VolRatio <1) or the relative necrosis ratio had increased by at least 10% (NecRatioInc ≥0.1), there was no significant difference in OS between Enneking wide and marginal margins. Variables measured by contrast-enhanced MRI could be used to evaluate chemotherapy response and increase the limb-salvage rate. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

Current status of immunotherapy for sarcomas

Although the development of anticancer drugs has improved the outcomes of bone and soft tissue sarcomas, the clinical outcome of patients with relapsed sarcomas remains unsatisfactory due to therapeutic toxicities and resistance to anticancer drugs. Therefore, novel therapeutic modalities are needed to improve the outcome of patients with bone and soft tissue sarcomas. Dendritic cells present tumor antigens and stimulate immune responses, and immune cells, such as cytotoxic T lymphocytes, kill tumor cells by recognizing tumor antigens. However, immune-suppressive conditions by immune regulator PD-1, CTLA-4 and regulatory T cells help tumor growth and progression. In this report, current immunotherapies including cellular immunotherapy and checkpoint inhibitors are introduced, and the advantages and disadvantages of the treatments are discussed.

Growth of epiphysis after epiphyseal-preservation surgery for childhood osteosarcoma around the knee joint

BACKGROUND

Epiphyseal-preservation surgery for osteosarcoma is an alternative method which has been indicated carefully to selected patients. The tumor-devitalised autograft treated with liquid nitrogen procedure is one of the biological reconstruction method to reconstruct the defect after tumor excision. The limb length discrepancy is usually appeared in children with their growth after limb-sparing surgery. This study was aimed to investigated the growth of residual epiphysis following epiphyseal-preservation surgery for childhood osteosarcoma around the knee joint.

METHODS

We retrospectively reviewed 12 patients with osteosarcoma who underwent epiphysis preserving tumor excision (8 in distal femur and 4 in proximal tibia) and reconstructed by using tumor-devitalized autograft treated with liquid nitrogen. The mean patient age was 11 (range, 6 to 14) years. The mean follow-up period were 63 (range, 41 to 90) months. Epiphysis transverse growth rate, epiphysis-width discrepancy (EWD) and collapse of epiphysis were evaluated by using pre- and post-operative whole standing leg radiographs. A retrospective chart review was performed to investigate functional outcome, complications and oncological status.

RESULTS

The mean growth of epiphysis rate was 12.6% (range, 3.3 to 28.0%) of affected side and 12.7% (range, 3.8 to 28.9%) of contralateral side, mean EWD was 0.1 mm (range, - 1.0 to 1.7 mm), mean LLD was + 26.1 mm (range, + 1 to + 48 mm) and two patients with distal femoral reconstruction underwent limb lengthening of tibia. There was no collapse of the residual epiphysis. The mean MSTS score was 27.7 (range, 18 to 30).

CONCLUSIONS

Epiphysis transverse growth was not diminished, and there was absence of epiphyseal collapse even after epiphyseal-preservation surgery in this small series of childhood osteosarcoma around the knee. With careful assessment for epiphyseal tumor involvement, epiphyseal-preservation surgery shall be possible, and could be an alternative method worth considering.

Inhibition of NADPH oxidase 2 induces apoptosis in osteosarcoma: The role of reactive oxygen species in cell proliferation

Osteosarcomas (OS) are aggressive tumors that are characterized by dysregulated growth and resistance to apoptosis. Reactive oxygen species (ROS) are thought to be important signal transduction molecules in the regulation of cell growth. ROS-generating nicotinamide adenine dinucleotide phosphate oxidase (NOX) family enzymes have previously been suggested to be involved in neoplastic proliferation. To examine whether NOX-mediated generation of intracellular ROS confers anti-apoptotic activity, and thus a growth advantage, the current study first analyzed the mRNA expression of NOX family members by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in five human OS cell lines. RT-PCR analysis revealed that NOX2 and NOX4 mRNAs were expressed in all the OS cell lines examined, whereas little or no NOX1 and NOX3 mRNAs were detected. By RT-qPCR, NOX2 mRNA expression levels were demonstrated to be higher than NOX4 mRNA expression levels. The viability of OS cells decreased in a dose-dependent manner with treatment of diphenylene iodonium (DPI), an inhibitor of flavoprotein-dependent oxidase. DPI treatment was observed to reduce intracellular ROS levels by ~50%, and increase the frequency of apoptosis by 30%. Notably, small interfering RNAs (siRNAs) targeting NOX2 significantly suppressed ROS generation; ROS depletion by DPI or NOX2 siRNAs induced apoptosis in OS cells. Together, the results of the present study indicate that NOX2-mediated ROS generation promotes cell survival and ROS depletion leads to apoptosis, thus highlighting the NOX2-ROS signaling pathway as a potential therapeutic target for OS treatment.

Methotrexate Free Chemotherapy and Limb Salvage Surgery for Paediatric Osteosarcoma in India

BACKGROUND

Osteosarcoma (OS) is the most common primary malignant tumor of bone. The survival of OS patients has steadily improved from <20% in the early 20th century to around 70% with current treatment. There are very few studies in pediatric OS from India analyzing various aspects of the disease. This study focuses on the clinical profile, treatment options, and their complications and survival outcomes in pediatric osteosarcoma (OS) patients.

MATERIALS AND METHODS

This was a retrospective observational study which included pediatric patients <14 years of age, with newly diagnosed OS confirmed by histological diagnosis. Medical records of all patients were reviewed for clinical profile, treatment data, surgical management, and treatment complications. Patients alive at the end of treatment were followed up and overall (OAS) and disease-free survival (DFS) were analyzed.

RESULTS

Sixty-two patients were diagnosed with OS during the study of whom 55 opted for treatment. Cisplatin, adriamycin, and ifosfamide (PAI) was offered as chemotherapy and was completed as planned in the majority of patients. Limb salvage surgery was performed in most patients (87%, n = 40). The local recurrence occurred in 7 patients. The 3 years overall survival for the cohort was 54.6% ± 7.8% and DFS was 43.4% ± 7.9%, with females and those with the localized disease having a significantly better DFS.

CONCLUSIONS

High dose methotrexate free chemotherapy can give good OAS in localized disease and LSS is feasible in most of the pediatric OS patients. However the modest DFS even for localized disease with PAI chemotherapy and extremely poor outcomes in the metastatic OS, demand further research and innovations in systemic therapy to improve outcomes.

Diagnosis and treatment of soft-tissue sarcomas of the extremities and trunk

The relatively low incidence and often atypical clinical presentation of soft-tissue sarcomas (STS) impedes early and adequate diagnosis. Patients may report on recently enlarged soft-tissue swellings, infrequently complain of painful lesions, or even have no symptoms at all.

A thorough diagnostic work-up is essential in order to distinguish between benign soft-tissue tumours and STSs. Patient history, clinical features and radiological findings all help in assessing the underlying pathology. ‘Worrying’ features such as recent increase in size, deep location relative to the fascia, a tumour exceeding 4 cm in size, and invasive growth patterns seen on imaging should prompt verification by biopsy.

Even though acquisition of biopsy material may be incomplete, one should bear in mind some essential rules. Regardless of the biopsy technique applied, the most direct route to the lump in question should be identified, contamination of adjacent structures should be avoided and a sufficient amount of tissue acquired.

Treatment of STS is best planned by a multidisciplinary team, involving experts from various medical specialities. The benchmark therapy consists of en bloc resection of the tumour, covered by a safety margin of healthy tissue. Depending on tumour histology, grade, local extent and anatomical stage, radiotherapy, chemotherapy and isolated hyperthermic limb perfusion may be employed.

Due to the complexity of treatment, any soft-tissue swelling suspected of malignancy is best referred directly to a sarcoma centre, where therapeutic management is carefully planned by an experienced multidisciplinary team.

Cite this article: EFORT Open Rev 2017;2:421-431. DOI: 10.1302/2058-5241.2.170005

[Avoiding pitfalls in the diagnostics of bone neoplasms from pathologists point of view : Importance of reference pathology]

Bone tumors account for only approximately 1 % of the total number of malignant tumors in humans so that they are only rarely diagnosed and appropriate experience is difficult to acquire. Although the number of entities is limited there exist very different clinical and radiological images depending on the manifestation in the different regions of the skeleton. Bone tumors are also histologically structured very differently even within a particular entity. Prior to the histopathological diagnosis the location of the lesion within the entire skeleton and in relation to the tumor-bearing bone must be clarified based on imaging findings, i.e. which bone is affected, which portion of the bone is affected and is the tumor centrally located in the marrow cavity, in the area of the corticalis or on the outside? It is known that bone tumors show diagnostically relevant preferential locations in both the total skeleton as well as within the affected bone depending on the entity and that the age of onset also varies. In this article the most common reasons for errors in assessment are discussed. In most cases it is possible for reference pathology to still correctly classify specific cases by a consistent consideration of diagnostic radiology in combination with morphology. Although diagnostic progress for specific entities of bone tumors has been achieved using molecular methods, the established principle of interdisciplinary cooperation is the prerequisite for the correct diagnosis of these tumors. The therapeutic consequences for patients can be substantial and result in life-long functional limitations depending on the diagnosis (e.g. joint resection for osteosarcoma in childhood and adolescence). A correct diagnosis is therefore of great importance for far-reaching therapeutic decision-making.

Is it safe to preserve the deltoid when resecting the proximal humerus for a primary malignant bone tumour? A comparative study

AIMS

Resection of the proximal humerus for the primary malignant bone tumour sometimes requires en bloc resection of the deltoid. However, there is no information in the literature which helps a surgeon decide whether to preserve the deltoid or not. The aim of this study was to determine whether retaining the deltoid at the time of resection would increase the rate of local recurrence. We also sought to identify the variables that persuade expert surgeons to choose a deltoid sparing rather than deltoid resecting procedure.

PATIENTS AND METHODS

We reviewed 45 patients who had undergone resection of a primary malignant tumour of the proximal humerus. There were 29 in the deltoid sparing group and 16 in the deltoid resecting group. Imaging studies were reviewed to assess tumour extension and soft-tissue involvement. The presence of a fat rim separating the tumour from the deltoid on MRI was particularly noted. The cumulative probability of local recurrence was calculated in a competing risk scenario.

RESULTS

There was no significant difference (adjusted p = 0.89) in the cumulative probability of local recurrence between the deltoid sparing (7%, 95% confidence interval (CI) 1 to 20) and the deltoid resecting group (26%, 95% CI 8 to 50). Patients were more likely to be selected for a deltoid sparing procedure if they presented with a small tumour (p = 0.0064) with less bone involvement (p = 0.032) and a continuous fat rim on MRI (p = 0.002) and if the axillary nerve could be identified (p = 0.037).

CONCLUSION

A deltoid sparing procedure can provide good local control after resection of the proximal humerus for a primary malignant bone tumour. A smaller tumour, the presence of a continuous fat rim and the identification of the axillary nerve on pre-operative MRI will persuade surgeons to opt for a deltoid resecting procedure. Cite this article: Bone Joint J 2017;99-B:1244-9.

What are the Oncologic and Functional Outcomes After Joint Salvage Resections for Juxtaarticular Osteosarcoma About the Knee?

BACKGROUND

Joint salvage surgery for patients with juxtaarticular osteosarcoma remains challenging, especially when the tumor invades the epiphysis. Because patients are surviving longer with current chemotherapy regimens, it is advantageous to retain native joints if possible, especially in young patients. However, the results using joint-preserving tumor resections in this context have not been well characterized.

QUESTIONS/PURPOSES

(1) What are the functional outcomes after limb salvage surgery at a minimum of 3 years? (2) What are the oncologic outcomes? (3) Is joint salvage surgery for epiphyseal tumors associated with an increased risk of local recurrence compared with metaphyseal tumors not invading the epiphysis? (4) What are the complications associated with joint salvage surgery?

METHODS

Between 2004 and 2013, we treated 117 patients with juxtaarticular osteosarcoma; of those, 43 (38%) were treated with joint salvage surgery, and 41 (95%) of the 43 patients are included in our study. The other two (5%) were lost to followup before 3 years (mean, 4.4 years; range, 3-11 years,). During the period in question, we generally performed joint salvage surgery in these patients when they had a favorable response to chemotherapy, did not have a pathologic fracture or extrusion of the tumor into the joint, and did not have a whole-epiphyseal osteolytic lesion, a large mass, or obvious neurovascular involvement. This report is a followup of an earlier study; the current study includes an additional nine patients, and additional followup of a mean of 19 months for the patients included in the earlier report. We ascertained overall survival and survival free from local recurrence which was estimated using the Kaplan-Meier method, functional status of the limb which was evaluated using the Musculoskeletal Tumor Society (MSTS)-93 scoring system, and recorded reconstructive complications including infection, fracture, skin necrosis, and nonunion. We compared oncologic and functional outcomes between patients with (n = 28) and without tumor extension to epiphysis (n =13). We also compared oncologic and functional outcomes among patients with different adjuvant treatments including microwave ablation (n = 11), cryoablation (n = 12), and navigation-assisted osteotomy (n = 5). Complications were tallied using records from our institutional database.

RESULTS

The overall Kaplan-Mayer survival rate was 82% (95% CI, 104-128 months) at 5 years. The overall Kaplan-Meier survivorship from local recurrence was 91% at 5 years (95% CI, 115-133 months). Three patients had a local recurrence, but none had local recurrence in or close to the remaining epiphysis. The MSTS scores ranged from 22 to 30 points, with a median of 28. There were no differences in survival rate, local recurrence, or MSTS scores between patients with a tumor that did not invade the epiphysis and those in whom the tumor did invade the epiphysis. There were differences in MSTS scores among patients with epiphyseal tumor extension in which different adjuvant techniques, including microwave ablation, cryoablation, and navigation-assisted osteotomy, were used. Additional surgical procedures were recorded for 10 patients (24%). Osteonecrosis of the residual epiphysis was detected 13 patients (31%).

CONCLUSIONS

Our findings suggest it is possible to salvage joints in selected patients with juxtaarticular osteosarcoma around the knee. The patients who have a favorable response to chemotherapy are the best candidates for this approach. Future studies might explore the role of adjuvant techniques of microwave ablation and cryoablation, particularly when the tumor invades the epiphysis, and whether resections can be facilitated with navigation.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Factors associated with local recurrence in operated osteosarcomas: A retrospective evaluation of 95 cases from a tertiary care center in a resource challenged environment

BACKGROUND AND OBJECTIVES

Local control of disease is one of the main goals of osteosarcoma management. We conducted a retrospective evaluation of 95 operated cases of osteosarcoma over 7 years to know about the factors associated with local recurrence in resource-challenged environment of the developing world.

METHODS

The factors which were evaluated and compared between local recurrence and non-local recurrence groups included demographic profile, site of tumor, whether biopsy done outside, type of surgery (limb salvage or amputation), presence of pathological fracture, vicinity of neurovascular bundle, tumor volume, histological subtype, chemotherapy induced necrosis, surgical margins, and delay in surgery. The time to local recurrence after surgery was also noted in the local recurrence group.

RESULTS

At a mean follow-up of 2.8 years, biopsy done from outside the treating center and delay in surgery after completion of neo-adjuvant chemotherapy emerged as significant risk factors for local recurrence. Most of the local recurrences (80%) occurred within 12 months of the primary surgery.

CONCLUSIONS

Lack of financial resources and availability of few tertiary care centers dealing with musculoskeletal oncology in the developing countries, lead to overburden with a long waiting list for tumor surgery making the scenario different from the Western world.