Analysis of Prognostic Factors in High-Grade Osteosarcoma of the Extremities in Children: A 15-Year Single-Institution Experience

Prognostic factors in high-grade pediatric osteosarcoma among children and young adults: Greek Nationwide Registry for Childhood Hematological Malignancies and Solid Tumors (NARECHEM-ST) data along with a systematic review and meta-analysis

The 5-year overall survival of children and adolescents with osteosarcoma has been in plateau during the last 30 years. The present systematic review (1976-2023) and meta-analysis aimed to explore factors implicated in the prognosis of children and young adults with high-grade osteosarcoma. Original studies including patients ≤30 years and the Nationwide Registry for Childhood Hematological Malignancies and Solid Tumors (NARECHEM-ST) data (2010-2021) referred to children ≤14 years were analysed. Individual participant data (IPD) and summary estimates were used to assess the n-year survival rates, as well as the association of risk factors with overall survival (OS) and event-free survival (EFS). IPD and the n-year survival rates were pooled using Kaplan-Meier and Cox regression models, and random effects models, respectively. Data from 8412 patients, including 46 publications, NARECHEM-ST data, and 277 IPD from 10 studies were analysed. The summary 5-year OS rate was 64% [95% confidence interval (95%CI): 62%-66%, 37 studies, 6661 patients] and the EFS was 52% (95%CI: 49%-56%, 30 studies, 5010 patients). The survival rates generally differed in the pre-specified subgroups. Limb-salvage surgery showed a higher 5-year OS rate (69%) versus amputation (47%). Good responders had higher OS rates at 3 years (94%) and 5 years (81%), compared to poor responders at 3 years (66%), and 5 years (56%). Patients with metastatic disease had a higher risk of death [Hazard Ratio (HR): 3.60, 95%CI: 2.52, 5.15, 11 studies]. Sex did not have an impact on EFS (HR females/males: 0.90, 95%CI: 0.54, 1.48, 3 studies), whereas age>18 years seems to adversely affect EFS (HR 18+/<10 years: 1.36, 95%CI: 1.09, 1.86, 3 studies). Our results summarize the collective experience on prognostic factors of high-grade osteosarcoma among children and young adults. Poor response to neoadjuvant chemotherapy and metastatic disease at diagnosis were confirmed as primary risk factors of poor outcome. International collaboration of osteosarcoma study groups is essential to improve survival.

Evaluating the Outcome and Patient Safety of Methotrexate, Doxorubicin, and Cisplatin Regimen for Chemotherapy in Osteosarcoma: A Meta-Analysis

BACKGROUND

Several studies of multi-drug regimens for osteosarcoma have shown different efficacies and are still controversial. Meanwhile, chemotherapy options have remained largely unchanged over a couple of decades. This study is designed to ascertain the outcome and safety of Methotrexate, Doxorubicin, and Cisplatin regimen for chemotherapy in osteosarcoma patients through the utilization of meta-analysis.

METHODS

We interrogated trials that compared the MAP regimen with other regimens as chemotherapy for osteosarcoma from several databases encompassing PubMed, Science Direct, and grey literature (Google Scholar) until December 2022. The analyzed outcomes including Event-Free Survival (EFS), Overall Survival (OS), Tumor Necrosis (TN) rate, and Adverse Event (AE) were then analyzed using RevMan 5.4 software in fixed or random effect models.

RESULTS

Our meta-analysis comprised 8 prospective articles that evaluated a cumulative number of 2920 OS patients. The analysis results indicated no meaningful difference in 5-year EFS (OR=0.99, 95% CI=0.77-1.27, [P = 0.91]) and neoadjuvant chemotherapy response (TN) (OR=0.76, 95% CI=0.49-1.17, [P = 0.22]) between the MAP and control groups. Furthermore, 5-year OS analysis revealed a significant association in the control group (OR=0.82, 95% CI=0.68-0.99, [P = 0.04]). However, the control group was associated with statistically meaningful AE compared to the MAP group, particularly in thrombocytopenia (OR=0.46, 95% CI=0.23-0.90, [P = 0.02]) and fever (OR=0.34, 95% CI=0.26-0.46, [P < 0.00001]).

CONCLUSION

The present meta-analysis showed that the MAP regimen remains preferable in treating osteosarcoma patients despite no significant outcome compared to the other regimens considering the less frequent AE in the MAP regimen.

Histopathological Response to Neoadjuvant Chemotherapy in Patients With Enneking Stage II Conventional Osteosarcoma of Extremities: A Retrospective-Single Institution Study in Vietnam

BACKGROUND

The standard treatment for localized osteosarcoma is neoadjuvant chemotherapy before surgery, followed by adjuvant chemotherapy. Our aim was to report the rate of histopathological response to neoadjuvant chemotherapy for the treatment of extremity osteosarcoma in Vietnam.

METHODS

We performed a retrospective study of stage II conventional osteosarcoma patients under 40 years-old who received MAP regimen as neoadjuvant chemotherapy at the Vietnam National Cancer Hospital between June 2019 and June 2022. Histopathological response was evaluated using the Huvos grading system, in which a good histopathological response was defined as a necrotic rate of 90% or more.

RESULTS

Thirty-five eligible patients were included in the study. Male patients accounted for 65.7%, with a median age of 16 years (range, 8-38 years). Of the 35 cases, 31 were reported as stage IIB (88.6%). The femur and tibia were the most common sites in our study, accounting for 51.4% and 34.3%, respectively. The most common pathologic subtype was osteoblastic osteosarcoma (68.6%), followed by chondroblastic subtype (20%). After two cycles of MAP-regimen neoadjuvant chemotherapy, 28 of 35 patients (80%) underwent limb-sparing surgery. A good histopathological response was observed in 18 of 35 patients (51.4%). There were significant correlations between the duration of symptoms (P = 0.016), LDH (P = 0.001) serum levels at initial presentation, and ALP (P = 0.043) serum levels at initial presentation with histopathological response.

CONCLUSION

This retrospective study suggests a possible association between symptom duration, pre-treatment LDH levels, and pre-treatment ALP levels with histopathological response rates. Additional clinical investigations with long-term follow-up are needed to investigate survival outcomes in the Asian population.

The Prognostic Value of Serum Biomarkers for Survival of Children with Osteosarcoma of the Extremities

BACKGROUND

Osteosarcoma is a highly aggressive malignant bone tumor that affects mainly adolescents and young adults. We analyzed serum biomarkers for their prognostic significance in children with osteosarcoma.

METHODS

In this retrospective study, we investigated the prognostic factors in 210 children who were treated for appendicular osteosarcoma, including patient age and sex, tumor site and size (≥8 cm or <8 cm), presence of metastasis, chemotherapy-induced tumor necrosis, serum levels of alkaline phosphatase (AP), C-reactive protein, serum hemoglobin, lactate dehydrogenase, erythrocyte sedimentation rate (ESR), leukocyte counts, platelet count, and neutrophil-lymphocyte ratio.

RESULTS

A multivariate Cox regression model showed that high level of AP [HR of 1.73; 95% CI, 1.02 to 2.94], poor chemotherapy-induced tumor necrosis [HR of 2.40; 95% CI, 1.41 to 4.08] and presence of metastases at presentation [HR of 3.71; 95% CI, 2.19 to 6.29] were associated with poor prognosis at 5 years (p < 0.05). Inadequate surgical margins [HR 11.28; 95% CI, 1.37 to 92.79] and high levels of ESR [HR 3.58; 95% CI, 1.29 to 9.98] showed a greater risk of local recurrence at 5 years follow-up (p < 0.05).

CONCLUSIONS

AP and ESR can identify osteosarcoma-diagnosed children with a greater risk of death and local recurrence, respectively.

Potential target identification for osteosarcoma treatment: Gene expression re-analysis and drug repurposing

Survival rate of osteosarcoma has remained plateaued for the past three decades. New treatment is needed to improve survival rate. Drug repurposing, a method to identify new indications of previous drugs, which saves time and cost compared to the de novo drug discovery. Data mining from gene expression profile was carried out and new potential targets were identified by using drug repurposing strategy. Selected data were newly categorized as pathophysiology and metastasis groups. Data were normalized and calculated the differential gene expression. Genes with log fold change ≥ 2 and adjusted p-value ≤ 0.05 were selected as primary candidate genes (PCGs). PCGs were further enriched to determine the secondary candidate genes (SCGs) by protein interaction analysis, upstream transcription factor and related-protein kinase identification. PCGs and SCGs were further matched with gene targeted of corresponding drugs from the Drug Repurposing Hub. A total of 778 targets were identified (360 from PCGs, and 418 from SCGs). This newly identified KLHL13 is a new candidate target based on its molecular function. KLHL13 was upregulated in clinical samples. We found 256 drugs from matching processes (50anti-cancerand206non-anticancerdrugs). Clinical trials of anti-cancer drugs from 5 targets (CDK4, BCL-2, JUN, SRC, PIK3CA) are being performed for osteosarcoma treatment. Niclosamide and synthetic PPARɣ ligands are candidates for repurposing due to the possibility based on their mechanism and pharmacology properties. Re-analysis of gene expression profile could identify new potential targets, confirm a current implication, and expand the chance of repurposing drugs for osteosarcoma treatment.

Correlation of radiological and histopathological response after neoadjuvant radiotherapy in soft tissue sarcoma

BACKGROUND

The aim of this study was to assess the association between radiological and histopathological response after neoadjuvant radiotherapy (nRT) in soft tissue sarcoma (STS), as well as the prognostic value of the different response evaluation methods on the oncological outcome.

METHODS

A retrospective cohort of patients with localized STS of the extremity and trunk wall, treated with nRT followed by resection were included. The radiological response was assessed by RECIST 1.1 (RECIST) and MR-adapted Choi (Choi), histopathologic response was evaluated according to the EORTC-STBSG recommendations. Oncological outcome parameters of interest were local recurrence-free survival (LRFS), disease metastases-free survival (DMFS), and overall survival (OS).

RESULTS

For 107 patients, complete pre- and postoperative pathology and imaging datasets were available. Most tumors were high-grade (77%) and the most common histological subtypes were undifferentiated pleomorphic sarcoma/not otherwise specified (UPS/NOS, 40%), myxoid liposarcoma (MLS, 21%) and myxofibrosarcoma (MFS, 16%). When comparing RECIST to Choi, the response was differently categorized in 58%, with a higher response rate (CR + PR) with Choi. Radiological responders showed a significant lower median percentage of viable cells (RECIST p = .050, Choi p = .015) and necrosis (RECIST p < .001), and a higher median percentage of fibrosis (RECIST p = .005, Choi p = .008), compared to radiological non-responders (SD + PD). RECIST, Choi, fibrosis, and viable cells were not significantly associated with altered oncological outcome, more necrosis was associated with poorer OS (p = .038).

CONCLUSION

RECIST, Choi and the EORTC-STBSG response score show incongruent results in response evaluation. The radiological response was significantly correlated with a lower percentage of viable cells and necrosis, but a higher percentage of fibrosis. Apart from necrosis, radiological nor other histopathological parameters were associated with oncologic outcomes.

Formulation and validation of a baseline prognostic score for osteosarcoma treated uniformly with a non-high dose methotrexate-based protocol from a low middle income healthcare setting: a single centre analysis of 594 patients

Introduction

The outcomes of osteosarcoma in low middle income countries (LMICs) are different due to patients presenting in advanced stages, resource constraints and the use of non-high-dose-methotrexate (HDMTX)-based regimens. This study derived and validated a prognostic score for osteosarcoma that integrates biologic and social factors and is tailored for patients from an LMIC setting using a non-HDMTX-based protocol.

Materials and methods

A retrospective study including osteosarcoma patients enrolled for treatment at a single tertiary care centre in India between 2003-19 was conducted. Baseline biologic and social characteristics were extracted from medical records and survival outcomes were noted. The cohort was randomised into a derivation and validation cohort. Multivariable Cox regression was used to identify baseline characteristics that were independently prognostic for survival outcomes in the derivation cohort. A score was derived from the prognostic factors identified in the derivation cohort and further validated in the validation cohort with estimation of its predictive ability.

Results

594 patients with osteosarcoma were eligible for inclusion in the study. Around one-third of the cohort had metastatic disease with 59% of the patients residing in rural areas. The presence of metastases at baseline (HR 3.39; p<0.001; score=3), elevated serum alkaline phosphatase (SAP) >450 IU/L (HR 1.57; p=0.001; score=1) and baseline tumour size > 10 cm (HR 1.68; p<0.001; score=1) were identified to be independent factors predicting inferior event free survival (EFS) and were included in development of the prognostic score. Patients were categorized as low risk (score 0), intermediate risk (score 1-3) and high risk (4-5). Harrell's c-indices for the score were 0.682, 0.608 and 0.657 respectively for EFS in the derivation, validation and whole cohort respectively. The timed AUC of ROC was 0.67 for predicting 18-month EFS in the derivation, validation and whole cohorts while that for 36-month EFS were 0.68, 0.66 and 0.68 respectively.

Conclusions

The study describes the outcomes among osteosarcoma patients from an LMIC treated uniformly with a non-HDMTX-based protocol. Tumor size, baseline metastases and SAP were prognostic factors used to derive a score with good predictive value for survival outcomes. Social factors did not emerge as determinants of survival.

Anti-EGFR Targeted Multifunctional I-131 Radio-Nanotherapeutic for Treating Osteosarcoma: In Vitro 3D Tumor Spheroid Model

The systemic delivery of doxorubicin (DOX) to treat osteosarcoma requires an adequate drug concentration to be effective, but in doing so, it raises the risk of increasing organ off-target toxicity and developing drug resistance. Herein, this study reveals a multiple therapeutic nanocarrier delivery platform that overcomes off-target toxicity by providing good specificity and imparting enhanced tumor penetration in a three-dimensional (3D) human MG-63 spheroid model. By synthesizing PEG-PLGA nanoparticles by the double emulsion method, encapsulating DOX and Na131I in the inner core, and conjugating with an epidermal growth factor receptor (EGFR) antibody, it is intended to specifically target human MG-63 cells. The nanocarrier is biocompatible with blood and has good stability characteristics. Na131I encapsulation efficiency was >96%, and radiochemical purity was >96% over 96 h. A DOX encapsulation efficacy of ~80% was achieved, with a drug loading efficiency of ~3%, and a sustained DOX release over 5 days. The nanocarrier EGFR antibody achieved a ~80-fold greater targeting efficacy to MG-63 cells (EGFR+) than fibroblast cells (EGFR−). The targeted multiple therapeutic DIE-NPs have a higher penetration and uptake of Na131I to the 3D model and a ~3-fold higher cytotoxicity than the DOX monotherapy (D-NPs). The co-administration of DOX and Na131I (DIE-NPs) disrupts DNA repair and generates free radicals resulting in DNA damage, triggering the activation of apoptosis pathways. This leads to inhibition of MG-63 cell proliferation and promotes cell cycle arrest in the G0/G1 phase. Furthermore, the PEGylated anti-EGFR functionalized DIE-NPs were found to be biocompatible with red blood cells and to have no adverse effects. This anti-EGFR targeted multifunctional I-131 radio-nanotherapeutic signifies a customizable specific targeted treatment for osteosarcoma.

Quality of Life and Limb Functionality in Adolescents and Young Adults Surviving Bone Tumors in the Lower Extremity in a Developing Country: A Cross-Sectional Study

Introduction Due to higher survival rates among patients with bone tumors, there is a growing interest in determining these individuals' limb functionality and psychosocial prognosis.

Objectives This study aimed to analyze the differences in functionality and quality of life (QoL) related to health in patients diagnosed with a malignant bone tumor during childhood, according to the type of surgery performed.

Materials and Methods A cross-sectional study was performed for patients older than 14 years who treated for osteosarcoma or Ewing's sarcoma of the lower limb by who receiving surgery. To assess lower limb functionality and QoL among patients surviving malignant bone tumors, 19 patients surviving osteosarcoma or Ewing's sarcoma of the lower extremity were studied. An evaluation of functionality and QoL was done using the “Enneking and Medical Outcomes Study Short-Form 36 scales.” We compared the functional results according to the surgical technique used. Categorical variables were compared according to the Mann–Whitney and Kruskal–Wallis tests, with an established 95% level of significance.

Results QoL among patients who had conservative surgery was not significantly better than amputee patients in the physical or mental aspects, nor in any of their components. Limb functionality, according to Enneking's staging, was significantly higher in non-amputee patients (p = 0.035).

Conclusion According to the data analysis done in this study, the QoL was found to be not significantly different, based on the type of surgery performed; however, there were differences in limb functionality.

MicroRNAs and osteosarcoma: Potential targets for inhibiting metastasis and increasing chemosensitivity

Osteosarcoma (OS) is the third most common cancer in young adults after lymphoma and brain cancer. Metastasis, like other cellular events, is dependent on signaling pathways; a series of changes in some proteins and signaling pathways pave the way for OS cells to invade and migrate. Ezrin, TGF-β, Notch, RUNX2, matrix metalloproteinases (MMPs), Wnt/β-catenin, and phosphoinositide 3-kinase (PI3K)/AKT are among the most important of these proteins and signaling pathways. Despite the improvements in treating OS, the overall survival of patients suffering from the metastatic disease has not experienced any significant change after surgical treatments and chemotherapy and 5-years overall survival in patients with metastatic OS is about 20%. Studies have shown that overexpression or inhibition of some microRNAs (miRNAs) has significant effects in limiting the invasion and migration of OS cells. The results of these studies highlight the potential of the clinical application of some miRNA mimics and miRNA inhibitors (antagomiRs) to inhibit OS metastasis in the future. In addition, some studies have shown that miRNAs are associated with the most important drug resistance mechanisms in OS, and some miRNAs are highly effective targets to increase chemosensitivity. The results of these studies suggest that miRNA mimics and antagomiRs may be helpful to increase the efficacy of conventional chemotherapy drugs in the treatment of metastatic OS. In this article, we discussed the role of various signaling pathways and the involved miRNAs in the metastasis of OS, attempting to provide a comprehensive review of the literature on OS metastasis and chemosensitivity.

Correlation of nuclear pIGF-1R/IGF-1R and YAP/TAZ in a tissue microarray with outcomes in osteosarcoma patients

Osteosarcoma (OS) is a genetically diverse bone cancer that lacks a consistent targetable mutation. Recent studies suggest the IGF/PI3K/mTOR pathway and YAP/TAZ paralogs regulate cell fate and proliferation in response to biomechanical cues within the tumor microenvironment. How this occurs and their implication upon osteosarcoma survival, remains poorly understood. Here, we show that IGF-1R can translocate into the nucleus, where it may act as part of a transcription factor complex. To explore the relationship between YAP/TAZ and total and nuclear phosphorylated IGF-1R (pIGF-1R), we evaluated sequential tumor sections from a 37-patient tissue microarray by confocal microscopy. Next, we examined the relationship between stained markers, clinical disease characteristics, and patient outcomes. The nuclear to cytoplasmic ratios (N:C ratio) of YAP and TAZ strongly correlated with nuclear pIGF-1R (r = 0.522, p = 0.001 for each pair). Kaplan-Meier analyses indicated that nuclear pIGF-1R predicted poor overall survival, a finding confirmed in the Cox proportional hazards model. Though additional investigation in a larger prospective study will be required to validate the prognostic accuracy of these markers, our results may have broad implications for the new class of YAP, TAZ, AXL, or TEAD inhibitors that have reached early phase clinical trials this year.

Pediatric Osteosarcoma: Pearls and Pitfalls

Osteosarcoma is a malignant bone tumor most commonly presenting in children. It has a bimodal distribution with a peak incidence occurring during the ages of 10-14 years old and in adults greater than age 65. The first peak of osteosarcoma correlates with the increased proliferation of bone during the pubertal growth period. Osteosarcoma most frequently presents with localized bone pain, swelling, and an antalgic gait. The patient may attribute symptoms to trauma or strenuous exercise, causing the patient to be managed conservatively. In these cases, the pain persists and eventually leads to further evaluation. The most common type of osteosarcoma is the conventional high-grade osteosarcoma. For conventional osteosarcoma, the diagnosis is typically made or strongly suggested based upon the initial radiographic appearance. Other types of osteosarcomas include low grade central, telangiectatic, small-cell, surface and intracortical. Consequently, it is important for radiologists to be aware of these subtypes and the imaging features that differentiate them from other etiologies to prevent a delay in treatment.

Combinatorial immunotherapy of N-803 (IL-15 superagonist) and dinutuximab with ex vivo expanded natural killer cells significantly enhances in vitro cytotoxicity against GD2+ pediatric solid tumors and in vivo survival of xenografted immunodeficient NSG mice

Background

Children with recurrent and/or metastatic osteosarcoma (OS), neuroblastoma (NB) and glioblastoma multiforme (GBM) have a dismal event-free survival (<25%). The majority of these solid tumors highly express GD2. Dinutuximab, an anti-GD2 monoclonal antibody, significantly improved event-free survival in children with GD2⁺ NB post autologous stem cell transplantation and enhanced natural killer (NK) cell-mediated antibody-dependent cell cytotoxicity. Thus, approaches to increase NK cell number and activity, improve persistence and trafficking, and enhance tumor targeting may further improve the clinical benefit of dinutuximab. N-803 is a superagonist of an interleukin-15 (IL-15) variant bound to an IL-15 receptor alpha Su-Fc fusion with enhanced biological activity.

Methods

The anti-tumor combinatorial effects of N-803, dinutuximab and ex vivo expanded peripheral blood NK cells (exPBNK) were performed in vitro using cytoxicity assays against GD2⁺ OS, NB and GBM cells. Perforin and interferon (IFN)-γ levels were measured by ELISA assays. Multiple cytokines/chemokines/growth factors released were measured by multiplex assays. Human OS, GBM or NB xenografted NOD/SCID/IL2rγnull (NSG) mice were used to investigate the anti-tumor combinatorial effects in vivo.

Results

N-803 increased the viability and proliferation of exPBNK. The increased viability and proliferation are associated with increased phosphorylation of Stat3, Stat5, AKT, p38MAPK and the expression of NK activating receptors. The combination of dinutuximab and N-803 significantly enhanced in vitro cytotoxicity of exPBNK with enhanced perforin and IFN-γ release against OS, GBM and NB. The combination of exPBNK+N-803+dinutuximab significantly reduced the secretion of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), platelet-derived growth factor-BB (PDGF-BB), and stem cell growth factor beta (SCGF-β) from OS or GBM tumor cells. Furthermore, OS or GBM significantly inhibited the secretion of regulated on activation, normal T cell expressed and presumably secreted (RANTES) and stromal cell-derived factor-1 alpha (SDF-1α) from exPBNK cells (p<0.001) but significantly enhanced monokine induced by gamma interferon (MIG) secretion from exPBNK cells (p<0.001). N-803 combined with dinutuximab and exPBNK cells significantly extended the survival of OS, GBM or NB xenografted NSG mice.

Conclusions

Our results provide the rationale for the development of a clinical trial of N-803 in combination with dinutuximab and ex vivo exPBNK cells in patients with recurrent or metastatic GD2⁺ solid tumors.

ONCOPEDS: A mobile application to improve early diagnosis and timely referral in childhood cancer in a low- and middle-income country-A pilot study

BACKGROUND

Diagnosis delay in children and adolescents with cancer is a public health problem in Peru that leads to high rates of advanced disease and mortality. We aimed to assess the implementation feasibility and potential utility of ONCOpeds®, a mobile application that provides consultations with pediatric oncologists, in reducing the latency to diagnosis (LD) and referral time (RT) among children and adolescents in Peru diagnosed with cancer.

MATERIAL AND METHODS

A prospective pilot study was conducted in the region of Callao between November 2017 and April 2018. Primary and secondary care providers were trained on the use of ONCOpeds in five educational sessions. Patients younger than 18 years who resided in Callao and were diagnosed with cancer at four pediatric cancer units in Lima were analyzed by referral type: ONCOpeds facilitated or conventional.

RESULTS

ONCOpeds was successfully installed in the smartphones of 78 primary and secondary care providers of Callao. During the study period, 23 new cases of cancer in children and adolescents from the region were diagnosed. Ten patients received ONCOpeds-facilitated referrals and 13 received conventional referrals. The RT decreased among those who received ONCOpeds-facilitated referrals by 66% (P = 0.02); however, the LD did not significantly decrease with the use of ONCOpeds.

CONCLUSIONS

The implementation of ONCOpeds was found to be feasible in this pilot study, having a potential utility in improving early diagnosis and referral in children and adolescents newly diagnosed with cancer. Directions for future research include multicenter studies with a larger population to further test the application's effectiveness.

Pretreatment Prediction of Relapse Risk in Patients with Osteosarcoma Using Radiomics Nomogram Based on CT: A Retrospective Multicenter Study

OBJECTIVE

To develop and externally validate a CT-based radiomics nomogram for pretreatment prediction of relapse in osteosarcoma patients within one year.

MATERIALS AND METHODS

In this multicenter retrospective study, a total of 80 patients (training cohort: 63 patients from three hospitals; validation cohort: 17 patients from three other hospitals) with osteosarcoma, undergoing pretreatment CT between August 2010 and December 2018, were identified from multicenter databases. Radiomics features were extracted and selected from tumor regions on CT image, and then, the radiomics signature was constructed. The radiomics nomogram that incorporated the radiomics signature and clinical-based risk factors was developed to predict relapse risk with a multivariate Cox regression model using the training cohort and validated using the external validation cohort. The performance of the nomogram was assessed concerning discrimination, calibration, reclassification, and clinical usefulness.

RESULTS

Kaplan-Meier curves based on the radiomics signature showed a significant difference between the high-risk and the low-risk groups in both training and validation cohorts (P < 0.001 and P = 0.015, respectively). The radiomics nomogram achieved good discriminant results in the training cohort (C-index: 0.779) and the validation cohort (C-index: 0.710) as well as good calibration. Decision curve analysis revealed that the proposed model significantly improved the clinical benefit compared with the clinical-based nomogram (P < 0.001).

CONCLUSIONS

This multicenter study demonstrates that a radiomics nomogram incorporated the radiomics signature and clinical-based risk factors can increase the predictive value of the osteosarcoma relapse risk, which supports the clinical application in different institutions.

Factors Affecting Prognosis and Survival in Extremity Osteosarcoma

Background

Osteosarcoma is a malignant bone tumor affecting mainly children and young adults and commonly involves extremities. The aim of this study was to assess the patient-related, tumor-related, and treatment-related factors affecting the overall survival in patients with non-metastatic extremity osteosarcoma.

Methodology

A retrospective, single institutional study of 100 patients with non-metastatic extremity osteosarcoma was done between 2014 and 2019. Age, sex, histologic type, tumor site, use of preoperative chemotherapy and its duration, response to chemotherapy, type of surgery, presence of local recurrence, occurrence of lung metastasis, and survival data were recorded. Survival analysis was done using Kaplan-Meier method. p < 0.05 by log-rank test was considered statistically significant. Statistical data were analyzed using SPSS v.25(IBM).

Results

The median age of presentation was 18 years with male sex preponderance. The most common site of presentation was distal femur, and commonest histological variant was osteoblastic osteosarcoma. Incidence of local recurrence was 9%, and lung metastasis was identified in 12% on follow-up. The 5-year overall survival (OS) was 65.5%, and 5-year local recurrence-free survival was 57.6%. The 5-year OS in neoadjuvant chemotherapy group was 80% compared to 39.5% in upfront surgery group (p = 0.015). The 5-year OS in patients with tumor necrosis > 90% and < 90% was 93.2% and 71.2%, respectively (p = 0.038). The 5-year OS in patients without lung metastasis was 76%, whereas none who developed lung metastasis has survived 5 years (p < 0.001).

Conclusion

The use of neoadjuvant chemotherapy, good response to chemotherapy, and the absence of lung metastasis on follow-up can independently predict better overall survival.

Telomerase-specific oncolytic immunotherapy for promoting efficacy of PD-1 blockade in osteosarcoma

Immune checkpoint inhibitors including anti-programmed cell death 1 (PD-1) antibody have recently improved clinical outcome in certain cancer patients; however, osteosarcoma (OS) patients are refractory to PD-1 blockade. Oncolytic virotherapy has emerged as novel immunogenic therapy to augment antitumor immune response. We developed a telomerase-specific replication-competent oncolytic adenovirus OBP-502 that induces lytic cell death via binding to integrins. In this study, we assessed the combined effect of PD-1 blockade and OBP-502 in OS cells. The expression of coxsackie and adenovirus receptor (CAR), integrins αvβ3 and αvβ5, and programmed cell death ligand 1 (PD-L1) was analyzed in two murine OS cells (K7M2, NHOS). The cytopathic activity of OBP-502 in both cells was analyzed using the XTT assay. OBP-502-induced immunogenic cell death was assessed by analyzing the level of extracellular ATP and high-mobility group box protein B1 (HMGB1). Subcutaneous tumor models for K7M2 and NHOS cells were used to evaluate the antitumor effect and number of tumor-infiltrating CD8+ cells in combination therapy. K7M2 and NHOS cells showed high expression of integrins αvβ3 and αvβ5, but not CAR. OBP-502 significantly suppressed the viability of both cells, in which PD-L1 expression and the release of ATP and HMGB1 were significantly increased. Intratumoral injection of OBP-502 significantly augmented the efficacy of PD-1 blockade on subcutaneous K2M2 and NHOS tumor models via enhancement of tumor-infiltrating CD8+  T cells. Our results suggest that telomerase-specific oncolytic virotherapy is a promising antitumor strategy to promote the efficacy of PD-1 blockade in OS.

Emergency Surgery in High Volume Osteosarcoma of Left Proximal Humerus Due to Vascular Compromise: A Case Report

BACKGROUND Osteosarcoma is the most common type of malignant bone tumor arising from mesenchymal stem cell. When occurring on the proximal humerus, it is associated with poor outcomes; there are numerous neurovascular structures around proximal humerus. Unfortunately, the degree of vascular involvement in osteosarcoma is rarely evaluated and reported. Thus, we would like to highlight our case. CASE REPORT We reported a case of left proximal humerus osteosarcoma causing dead limb in a 14-year-old boy. The dead limb progressed in the span of 3 weeks. An emergency forequarter amputation (FQA) was conducted to prevent further complications such as septicemia and mortality. Two months after the surgery, the patient had improved quality of life. One year after, the patient had no local recurrence. However, there was a lung metastasis detected 9 months after the surgery. The patient died 13 months after the surgery. CONCLUSIONS Osteosarcoma of the proximal humerus can potentially compromise vascular structures. Early diagnosis and treatment are mandatory to prevent such complications.

Prognostic impact of diagnostic and treatment delays in children with osteosarcoma

BACKGROUND

The aim of this study is to evaluate the relationship between the latency to diagnosis (LD) and the time to completion of chemotherapy (TCC) with clinical outcomes in children with osteosarcoma.

METHODS

We performed a retrospective analysis of all patients who received treatment for osteosarcoma in two tertiary centers in Peru from 2008 to 2015. All causes of delayed LD or TCC were evaluated. Overall survival (OS) and event-free-survival (EFS) were estimated and compared according to LD, TCC, and established clinical prognostic factors.

RESULTS

One hundred and thirteen patients were included in the study. The median LD was 13.5 weeks (interquartile range, 10-18.5 weeks). No association was observed among clinical stage, tumor size, and LD. Delayed LD was not associated with a worse clinical outcome. Multivariate analysis confirmed that OS and EFS were significantly worse in cases of a delayed TCC (≥4 weeks), with hazard ratios of 2.70 (1.11-6.76, P = 0.003) and 1.13 (1.00-1.26, P = 0.016), respectively. Most delays in TCC (85%) were due to extramedical reasons (e.g., lack of available hospital beds).

CONCLUSION

The LD did not seem to influence the EFS and OS in pediatric patients with osteosarcoma. However, a delay in TCC from any cause is independently associated with poor outcome in pediatric patients with osteosarcoma. Based on these results, further efforts may be needed to avoid treatment delays in patients with osteosarcoma in middle-income countries.

Prognostic factors in osteosarcoma: A study level meta-analysis and systematic review of current practice

Background

A consensus has not yet been reached regarding the abilities of gender, age, tumor size, tumor location, histologic subtypes, and surgery in the prediction of survival in osteosarcoma. We aimed to disclose their prognostic significance by conducting a meta-analysis of all the published data from the last decade.

Materials and Methods

Electronic database searches were conducted in PubMed, Embase, and Web of Science for relevant articles published within the last ten years. The pooled hazard ratio (HR) and corresponding 95% confidence interval (CI) were obtained to evaluate the prognostic values of the target factors.

Results

A total of 18,126 patients from 40 studies were eventually included. Results indicated that gender (male vs. female: 1.21, 95% CI, 1.11–1.32; female vs. male: 0.85, 95% CI, 0.75–0.98), age (12–20 vs. ≤12: 1.37, 95% CI, 1.13–1.65; ≥20 vs. <20: 1.29, 95% CI, 1.08–1.55; ≥40 vs. <40: 1.63, 95% CI, 1.21–2.20; ≥50 vs. <25: 2.60, 95% CI, 1.92–3.53; ≥60 vs. <60: 1.11, 95% CI, 1.06–1.18), tumor location (non-extremities vs. extremities: 2.10, 95% CI, 1.76–2.51; proximal vs. distal femur: 3.68, 95% CI: 1.51–8.96; proximal vs. distal humerus: 3.15, 95% CI: 1.53–6.49), tumor size (≥5 vs. <5: 1.42, 95% CI, 1.09–1.86; >8 vs. ≤8: 1.55, 95% CI, 1.07–2.24; >9 vs. ≤9: 1.44, 95% CI, 1.05–1.96), chemotherapy response (poor vs. good: 2.45, 95% CI, 2.02–2.97; good vs. poor: 0.41, 95% CI, 0.34–0.48), and surgery (yes vs. no: 0.45, 95% CI, 0.36–0.57; amputation vs. salvage: 2.34, 95% CI, 1.47–3.74) were significantly associated with overall survival in osteosarcoma patients.

Conclusion

The meta-analysis demonstrated that male patients, older age, large tumor size, non-extremity osteosarcoma, proximal osteosarcoma, poor chemotherapy response, no surgical treatment, and amputation surgery were correlated with a poor prognosis in osteosarcoma patients.

Early response monitoring of neoadjuvant chemotherapy using [18F]FDG PET can predict the clinical outcome of extremity osteosarcoma

Background

To propose a personalized therapeutic approach in osteosarcoma treatment, we assessed whether sequential [¹⁸F]FDG PET/CT (PET/CT) could predict the outcome of patients with osteosarcoma of the extremities after one cycle and two cycles of neoadjuvant chemotherapy.

Methods

A total of 73 patients with AJCC stage II extremity osteosarcoma treated with 2 cycles of neoadjuvant chemotherapy, surgery, and adjuvant chemotherapy were retrospectively analyzed in this study. All patients underwent PET/CT before (PET0), after 1 cycle (PET1), and after the completion of neoadjuvant chemotherapy (PET2), respectively. Maximum standardized uptake value (SUV_max) (corrected for body weight) and the % changes of SUV_max were calculated, and histological responses were evaluated after surgery. Receiver-operating characteristic (ROC) curve analyses and the Cox proportional hazards models were used to analyze whether imaging and clinicopathologic parameters could predict event-free survival (EFS).

Results

A total of 36 patients (49.3%) exhibited a poor histologic response and 17 patients (23.3%) showed events (metastasis in 15 and local recurrence in 2). SUV_max on PET2 (SUV2), the percentage change of SUV_max between PET0 and PET1 (Δ%SUV01), and between PET0 and PET2 (Δ%SUV02) most accurately predicted events using the ROC curve analysis. SUV2 (relative risk, 8.86; 95% CI, 2.25–34.93), Δ%SUV01 (relative risk, 5.97; 95% CI, 1.47–24.25), and Δ%SUV02 (relative risk, 6.00; 95% CI, 1.16–30.91) were independent predicting factors for EFS with multivariate analysis. Patients with SUV2 over 5.9 or Δ%SUV01 over − 39.8% or Δ%SUV02 over − 54.1% showed worse EFS rates than others (p < 0.05).

Conclusions

PET evaluation after 1 cycle of presurgical chemotherapy can predict the clinical outcome of extremity osteosarcoma. [¹⁸F]FDG PET, which shows a potential role in the early evaluation of the modification of timing of local control, can be a useful modality for early response monitoring of neoadjuvant chemotherapy.

Tissue-engineered 3D models for elucidating primary and metastatic bone cancer progression

Malignant bone tumors are aggressive neoplasms which arise from bone tissue or as a result of metastasis. The most prevalent types of cancer, such as breast, prostate, and lung cancer, all preferentially metastasize to bone, yet the role of the bone niche in promoting cancer progression remains poorly understood. Tissue engineering has the potential to bridge this knowledge gap by providing 3D in vitro systems that can be specifically designed to mimic key properties of the bone niche in a more physiologically relevant context than standard 2D culture. Elucidating the crucial components of the bone niche that recruit metastatic cells, support tumor growth, and promote cancer-induced destruction of bone tissue would support efforts for preventing and treating these devastating malignancies. In this review, we summarize recent efforts focused on developing in vitro 3D models of primary bone cancer and bone metastasis using tissue engineering approaches. Such 3D in vitro models can enable the identification of effective therapeutic targets and facilitate high-throughput drug screening to effectively treat bone cancers. STATEMENT OF SIGNIFICANCE: Biomaterials-based 3D culture have been traditionally used for tissue regeneration. Recent research harnessed biomaterials to create 3D in vitro cancer models, with demonstrated advantages over conventional 2D culture in recapitulating tumor progression and drug response in vivo. However, previous work has been largely limited to modeling soft tissue cancer, such as breast cancer and brain cancer. Unlike soft tissues, bone is characterized with high stiffness and mineral content. Primary bone cancer affects mostly children with poor treatment outcomes, and bone is the most common site of cancer metastasis. Here we summarize emerging efforts on engineering 3D bone cancer models using tissue engineering approaches, and future directions needed to further advance this relatively new research area.

Expression of miR-664-3p in Osteosarcoma and Its Effects on the Proliferation and Apoptosis of Osteosarcoma Cells

BACKGROUND

To explore the expression level of miR-664-3p in osteosarcoma and its effects on the proliferation and apoptosis of osteosarcoma cells.

METHODS

Specimens of osteosarcoma tissues were collected from 41 cases undergoing surgical treatment in the Orthopedics Department of Wuhan Puai Hospital, Wuhan, China from January 2015 to February 2018. Another 40 cases of normal bone tissue were collected. The expression of miR-664-3p were detected using quantificational real-time polymerase chain reaction. miR-664-3p mimics, miR-664-3p inhibitor and miR-664-3p negative control (NC) were used to transfect U2-OS, which were named as mimics group, inhibitor group and NC group, respectively. MTT assay was adopted to detect the effects of microRNA-664-3p on the proliferation of U2-OS after 24, 48, 72, 96 and 120 hours of transfection. Flow cytometry was applied to measure the apoptosis rate of U2-OS after miR-664-3p transfection. Finally, Western Blot was employed to detect the expression of proteolipid protein 2 (PLP2).

RESULTS

The total apoptosis rate of cells in the inhibitor group was obviously higher than those in the mimics group and the NC group (P<0.001). The relative expression level of PLP2 in the inhibitor group was significantly lower than those in the mimics group and the NC group (P<0.001).

CONCLUSION

MiR-664-3p may be involved in the occurrence and development of osteosarcoma, and can regulate the proliferation and apoptosis of U2-OS cells, and the expression of PLP2. Besides, miR-664-3p may become a novel molecular biological indicator for the diagnosis, targeted treatment and prognosis assessment of osteosarcoma.

Osteosarcoma journey over two decades in India: Small steps, big changes

BACKGROUND

The management of osteosarcoma is challenging especially in lower-income and middle-income countries, and there is an unmet need to evolve efficient and sustainable chemotherapy regimens.

METHODS

We compared the outcomes in nonmetastatic osteosarcoma patients treated with three sequential non-high-dose methotrexate-based combination chemotherapy protocols at a single tertiary care center over two decades. The first protocol, OGS-99, involved dose-intense, alternating dyads of three drugs: doxorubicin (Dox), cisplatin (CDDP), and ifosfamide (Ifo). The second protocol, OGS-99 enhanced, included OGS-99 drugs with etoposide and enhanced supportive care. The OGS-12 protocol involved dose-dense administration of eight sequential dyads of Dox, CDDP and Ifo, universal growth factor prophylaxis and targeted nutritional support. Event-free survival (EFS), overall survival (OS), and toxicity were reported using a retrospective chart review in the OGS-99 and OGS-99 enhanced protocols and prospectively in the OGS-12 protocol.

RESULTS

A total of 41, 94, and 385 treatment-naïve, consecutive, nonmetastatic patients with extremity osteosarcoma were treated with the OGS-99 (2000-2005), OGS-99 enhanced (2010), and OGS-12 (2011-2016), respectively. At a median follow-up of 19, 86, and 39 months, the five-year EFS rates were 38%, 50%, and 62% in the OGS-99, OGS-99 enhanced, and OGS-12, respectively. The corresponding rates of five-year OS were nonevaluable, 60% and 77%, respectively, with acceptable rates of grade 3-4 toxicities: febrile neutropenia (40%), thrombocytopenia (36%), anemia (51%), and 1% deaths related to toxicity.

CONCLUSIONS

Sequential selection of an intelligent, dose-dense chemotherapy regimen together with enhanced supportive care resulted in marked improvement in outcomes of nonmetastatic osteosarcoma and this "small steps-big changes" model deserves wider recognition and usage.

Osteosarcoma progression is associated with increased nuclear levels and transcriptional activity of activated β-Catenin

Osteosarcoma (OS) is an aggressive primary bone malignancy that has peak incidence in children and young adults <25 years of age. Despite current multimodal treatments, no significant change in patient outcome has been observed in two decades. Presently, there is a lack of established, reliable baseline prognostic markers for aggressive OS, other than extent and site of disease involvement. The canonical Wnt/β-catenin pathway controls multiple cellular processes, and is known to be a critical pathway in OS progression. This pathway regulates cellular levels of β-catenin, which is a significant player in the oncogenesis and progression of many cancers. We investigated the relationship between β-catenin, more specifically, the transcriptionally active form of β-catenin, Activated β-Catenin (ABC), and OS progression. Using an in vitro model, we observed that cellular/nuclear ABC levels, but not cellular/nuclear β-catenin levels, increase with the degree of aggressiveness in OS. Our results demonstrate a strong association between nuclear-ABC levels and aggressive OS in vitro. Furthermore, we observed significant correlation between positive nuclear-ABC and patient age and tumor stage. Our results support the potential use of ABC as a predictive marker for risk stratification in OS.

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.

Factors associated with abandonment of therapy by children diagnosed with solid tumors in Peru

BACKGROUND

Abandonment of treatment is a major cause of treatment failure and poor survival in children with cancer in low- and middle-income countries. The incidence of treatment abandonment in Peru has not been reported. The aim of this study was to examine the prevalence of and factors associated with treatment abandonment by pediatric patients with solid tumors in Peru.

METHODS

We retrospectively reviewed the sociodemographic and clinical data of children referred between January 2012 and December 2014 to the two main tertiary centers for childhood cancer in Peru. The definition of treatment abandonment followed the International Society of Paediatric Oncology, Paediatric Oncology in Developing Countries, Abandonment of Treatment recommendation.

RESULTS

Data from 1135 children diagnosed with malignant solid tumors were analyzed, of which 209 (18.4%) abandoned treatment. Bivariate logistic regression analysis showed significantly higher abandonment rates in children living outside the capital city, Lima (forest; odds ratio [OR] 3.25; P < 0.001), those living in a rural setting (OR 3.44; P < 0.001), and those whose parent(s) lacked formal employment (OR 4.39; P = 0.001). According to cancer diagnosis, children with retinoblastoma were more likely to abandon treatment compared to children with other solid tumors (OR 1.79; P = 0.02). In multivariate regression analyses, rural origin (OR 2.02; P = 0.001) and lack of formal parental employment (OR 2.88; P = 0.001) were independently predictive of abandonment.

CONCLUSION

Treatment abandonment prevalence of solid tumors in Peru is high and closely related to sociodemographical factors. Treatment outcomes could be substantially improved by strategies that help prevent abandonment of therapy based on these results.

Tumor necrosis and clinical outcomes following neoadjuvant therapy in soft tissue sarcoma: A systematic review and meta-analysis

BACKGROUND

The prognostic role of tumor necrosis following neoadjuvant therapy is established in bone sarcomas but remains unclear in soft tissue sarcomas (STS).

METHODS

We searched MEDLINE, MEDLINE in progress, EMBASE and Cochrane to identify studies that investigated neoadjuvant therapy in STS. Studies were required to report survival data based on extent of necrosis, or provided individual patient data allowing estimation thereof. Hazard ratios (HR) for relapse-free (RFS) and overall survival (OS) and odds ratios (OR) for recurrence at 3 years and for death at 5 years were pooled in a random effect meta-analysis. Associations between patient characteristics and attainment of ≥90% necrosis were explored.

RESULTS

21 studies comprising 1663 patients were included. Extremity tumors were most common (n = 1554; 93%). Induction regimens included chemotherapy with radiotherapy (n = 924; 56%), chemotherapy alone (n = 412; 25%), radiotherapy alone (n = 78; 5%), isolated limb perfusion (ILP) (n = 231; 14%), and targeted therapy/radiotherapy (n = 18; 1%). Patients with <90% necrosis had higher hazard of recurrence (hazard ratio [HR] 1.47; 95% CI: 1.06-2.04; p = 0.02) and death (HR 1.86; 95% CI: 1.41-2.46; p < 0.001). Risk of recurrence at 3 years (OR = 3.35; 95% CI: 2.27-4.92; p < 0.001) and of death at 5 years (OR 2.60; 95% CI: 1.59-4.26; p < 0.001) were similarly increased. Compared to other modalities, ILP was associated with higher odds of achieving ≥90% necrosis (OR 12.1; 95% CI: 3.69-39.88; p < 0.001).

CONCLUSION

Tumour necrosis <90% following neoadjuvant therapy is associated with increased recurrence risk and inferior OS in patients with STS.

Meta-analysis of serum lactate dehydrogenase and prognosis for osteosarcoma

BACKGROUNDS

A large number of studies have reported the relationships between serum lactate dehydrogenase (LDH) and prognosis of osteosarcoma. However, the result is still controversial and no consensus has been reached. Therefore, we performed a meta-analysis to evaluate the prognostic role of serum LDH in osteosarcoma patients.

METHODS

We performed the systematic computerized search for eligible articles from PubMed, Embase, and Cochrane databases until December 21, 2017. The pooled hazard ratio (HR) and 95% confidence intervals (CIs) of overall survival (OS) and event-free survival (EFS) were obtained to assess the prognostic value of serum LDH.

RESULTS

A total of 18 studies with 2543 osteosarcoma patients were included. Overall, 15 studies assessed the elevated serum LDH level on OS and the pooled HR was 1.87 (95% CI = 1.58-2.20). Meanwhile, the pooled HR to evaluate the relationship between serum LDH and EFS in 9 studies was 1.78 (95% CI = 1.51-2.10). The same results were acquired when these studies were stratified by Enneking stage, geographic region, and sample size. No heterogeneity existed between these subgroups (P > .05). Begg's funnel plot and Egger's test (OS: P = .04; EFS: P = .34) showed that possible publication bias might exist in OS studies. Sensitivity analysis suggested the pooled HR was robust.

CONCLUSIONS

This meta-analysis demonstrates that elevated serum LDH level is apparently associated with lower EFS rate and serum LDH could be a prognostic biomarker for osteosarcoma patients.

The extremity localized classic osteosarcomas have better survival than the axial non-classics

BACKGROUND

Osteosarcoma is one of the most malignant primary bone cancers, while is rarely reported in China. Of note, very few data of prognosis has been documented in this region. Thus, we carried a retrospective study to identify prognostic factors and to analyze outcomes in patients of both classic and non-classic high-grade osteosarcomas. Classic osteosarcoma is defined as of high-grade histology, age below 40 years, with extremity localized primary tumor, and without detectable metastasis at primary diagnosis.

METHODS

A total of 98 patients (68 classic and 30 non-classic) aged from 4 to 64 years old were diagnosed as high-grade osteosarcoma from 2008 to 2015 in Nanfang Hospital, Guangzhou, China. Univariate and multivariate analyses were performed to identify the independent predictors for overall survival and event-free survival. Kaplan-Meier method was used for survival analysis.

RESULTS

The median overall survival was 117 vs. 21 months, and the median event-free survival was 31 vs. 6 months in classic and non-classic osteosarcoma, respectively. The most frequently found tumor site was around the knee. The classic osteosarcoma had better overall survival and event-free survival than the non-classics. Tumor site and primary metastasis were found to be associated with overall survival and event-free survival in the univariate analysis. In the multivariate Cox regression analysis, tumor site and primary metastasis were each verified as independent prognostic factors. However, no similar result was found in elevated serum alkaline phosphatase or lactate dehydrogenase. Amputation or limb salvage surgery had no significant effect on overall survival and event-free survival in the extremity osteosarcomas. Classic osteosarcomas with extremity tumor site and free of primary metastasis exhibited better overall survival and event-free survival, while the axial and metastatic non-classics exhibited the worse.

CONCLUSIONS

The extremity classic osteosarcomas have better survivals than the axial non-classic cases. Amputation and limb salvage surgery make no significant change in overall survival and event-free survival in the extremity osteosarcomas.

TRIAL REGISTRATION

Nanfang2013071; Date of registration: 7 September 2013 (retrospectively registered).

Germline and somatic genetics of osteosarcoma - connecting aetiology, biology and therapy

Clinical outcomes and treatment modalities for osteosarcoma, the most common primary cancer of bone, have changed very little over the past 30 years. The peak incidence of osteosarcoma occurs during the adolescent growth spurt, which suggests that bone growth and pubertal hormones are important in the aetiology of the disease. Tall stature, high birth weight and certain inherited cancer predisposition syndromes are well-described risk factors for osteosarcoma. Common genetic variants are also associated with osteosarcoma. The somatic genome of osteosarcoma is highly aneuploid, exhibits extensive intratumoural heterogeneity and has a higher mutation rate than most other paediatric cancers. Complex pathways related to bone growth and development and tumorigenesis are also important in osteosarcoma biology. In this Review, we discuss the contributions of germline and somatic genetics, tumour biology and animal models in improving our understanding of osteosarcoma aetiology, and their potential to identify novel therapeutic targets and thus improve the lives of patients with osteosarcoma.

Factors associated with the latency to diagnosis of childhood cancer in Peru

BACKGROUND

The latency to diagnosis is the time between the detection of a patient's first symptoms and the cancer diagnosis. The aim of this study was to identify the latency to the diagnosis of cancer in children in Peru and the clinical and sociodemographic factors associated with this latency.

METHODS

All patients diagnosed with lymphoma and solid tumors between 2012 and 2014 at a social security referral hospital in Peru were retrospectively evaluated. Clinical and demographic variables were analyzed to assess their association with the latency to diagnosis.

RESULTS

A total of 284 patients younger than 18 years of age were included in the study. The median time to diagnosis was 8.8 weeks, with a median patient interval of 2 weeks and diagnostic interval of 4.4 weeks. We found significant differences in the latency to diagnosis for different types of cancer (longer for Hodgkin lymphoma and shorter for Wilms tumor). Older children had significantly longer latencies to diagnosis (P = 0.048; OR: 1.05, 95% CI [1.0-1.1]), as did children who were first diagnosed by a general physician rather than by a pediatrician or surgeon (P = 0.028; OR: 2.1, 95% CI [1.1-4.2]). Parental age, level of education, marital status, metastatic disease, clinical stage, and gender did not significantly affect latency to diagnosis as analyzed by a multivariate analysis.

CONCLUSION

In Peru, median latency to diagnosis was comparable to that described in developing countries, where the index of suspicion for childhood cancer remains low. It is crucial to establish strategies to optimize early diagnoses using associated factors.

Review of Osteosarcoma and Current Management

Osteosarcoma is the most common primary malignancy of bone in children and young adults. This tumor has a very heterogeneous genetic profile and lacks any consistent unifying event that leads to the pathogenesis of osteosarcoma. In this review, some of the important genetic events involved in osteosarcoma will be highlighted. Additionally, the clinical diagnosis of osteosarcoma will be discussed, as well as contemporary chemotherapeutic and surgical management of this tumor. Finally, the review will discuss some of the novel approaches to treating this disease.