Prognostic value of pathologic fracture in patients with high grade localized osteosarcoma: a systemic review and meta-analysis of cohort studies

Are Pathologic Fractures in Patients With Osteosarcoma Associated With Worse Survival Outcomes? A Systematic Review and Meta-analysis

BACKGROUND

Pathologic fractures occur in 5% to 10% of patients with osteosarcoma, and prior studies have suggested they are prognostically important. However, because they represent an uncommon event in the setting of an already rare disease, most studies fail to reach conclusive findings, and there is no agreement about how best to treat pathologic fractures.

QUESTIONS/PURPOSES

(1) Is the occurrence of a pathologic fracture in patients with osteosarcoma associated with poorer overall survivorship? (2) Is the occurrence of a pathologic fracture in patients with osteosarcoma associated with poorer local recurrence-free survival or metastasis-free survival? (3) Is the surgical approach (amputation or limb salvage) associated with differences in local recurrence rates in patients with osteosarcoma with pathologic fractures?

METHODS

This systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Our study was registered in PROSPERO (ID: 380459). A search of the PubMed and Embase databases resulted in 625 and 747 titles, respectively. After application of the inclusion and exclusion criteria, 21 articles were finally included. Quality assessment of all studies was performed using the Newcastle-Ottawa Quality Assessment Scale. The Risk of Bias In Non-Randomized Studies of Interventions tool was used in the 11 articles that evaluated the effect of an intervention (amputation or limb salvage) on local recurrence rates. The relative risk (RR) was calculated to compare outcomes in patients with osteosarcoma with pathologic fractures and those without. Heterogeneity among studies was calculated using the I 2 statistic. The pooled RR was calculated using the fixed-effects or random-effects model depending on study heterogeneity. The fragility index and the ratio between the fragility index and the total number of participants for each outcome was additionally calculated to assess the robustness of our results. A total of 7604 patients with osteosarcoma, 12% of whom (885) had pathologic fractures, were included in our analysis.

RESULTS

Pathologic fractures in patients with osteosarcoma were associated with lower 3-year (RR 1.53 [95% CI 1.29 to 1.82]; p < 0.001) and 5-year overall survival (RR 1.27 [95% CI 1.16 to 1.40]; p < 0.001). No difference in recurrence rates was found between patients with osteosarcoma with pathologic fractures and those without (RR 1.22 [95% CI 0.91 to 1.64]; p = 0.18). However, having a pathologic fracture was associated with an increased risk of developing metastasis (RR 1.33 [95% CI 1.08 to 1.63]; p = 0.01). Treatment with limb salvage surgery was not associated with a higher rate of local recurrence (RR 1.58 [95% CI 0.88 to 2.85]; p = 0.13).

CONCLUSION

In light of these findings, surgeons should be aware that after appropriate case selection, patients with osteosarcoma and pathologic fractures undergoing limb salvage surgery may have similar rates of local recurrence to those undergoing amputation. Therefore, a pathologic fracture may no longer be an absolute contraindication for limb salvage surgery. Future studies adjusting for potential confounders such as tumor size, tumor location, and response to neoadjuvant therapy would provide further insight into the effect of pathologic fractures on our assessed outcomes.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Research of the Active Components and Potential Mechanisms of Qingfei Gujin Decoction in the Treatment of Osteosarcoma Based on Network Pharmacology and Molecular Docking Technology

Aim. Qingfei Gujin Decoction (QGD) has been shown to be effective against osteosarcoma. This research was aimed at investigating the main active ingredients and potential mechanisms of QGD acting on osteosarcoma through network pharmacology and molecular docking techniques. Methods. The active ingredients and targets of QGD were screened from the TCMSP database, and the predicted targets were obtained from the PharmMapper database. Meanwhile, the targets of osteosarcoma were collected using OMIM, PharmGKB, and DisGeNET databases. Then, GO and KEGG enrichment analyses were performed by RStudio. PPI and drug-ingredient-target networks were constructed using Cytoscape 3.2.1 to screen the major active ingredients, key networks, and targets. Finally, molecular docking of key genes and their regulatory active ingredients was performed using AutoDockTools 1.5.6 software. Results. 38 active ingredients were collected, generating 89 cross-targets; quercetin, luteolin, β-sitosterol, and kaempferol were the main active ingredients of QGD acting on osteosarcoma, and major signaling pathways such as PI3K-Akt signaling pathway, MAPK signaling pathway, and IL-17 signaling pathway were observed. TP53, SRC, and ESR1 were identified as key proteins that docked well with their regulated compounds. Conclusion. QGD is effective against osteosarcoma through multicomponent, multitarget, and multipathway. This study was helpful for finding effective targets and compounds for osteosarcoma treatment.

Do Disparities in Wait Times to Operative Fixation for Pathologic Fractures of the Long Bones and 30-day Complications Exist Between Black and White Patients? A Study Using the NSQIP Database

BACKGROUND

Racial disparities in outcomes after orthopaedic surgery have been well-documented in the fields of arthroplasty, trauma, and spine surgery; however, little research has assessed differences in outcomes after surgery for oncologic musculoskeletal disease. If racial disparities exist in the treatment of patients with pathologic long bone fractures, then they should be identified and addressed to promote equity in patient care.

QUESTIONS/PURPOSES

(1) How do wait times between hospital admission and operative fixation for pathologic fractures of long bones differ between Black and non-Hispanic white patients, after controlling for confounding variables using propensity score matching? (2) How does the proportion of patients with 30-day postoperative complication differ between these groups after controlling for confounding variables using propensity score matching?

METHODS

Using the National Surgical Quality Improvement Program database, we analyzed 828 patients who underwent fixation for pathologic fractures from 2012 to 2018. This database not only provides a large enough sample of pathologic long bone fracture patients to conduct the present study, but also it contains variables such as time from hospitalization to surgery that other national databases do not. After excluding patients with incomplete data (4% of the initial cohort), 775 patients were grouped by self-reported race as Black (12% [94]) or white (88% [681]). Propensity score matching using a 1:1 nearest-neighbor match was then used to match 94 Black patients with 94 white patients according to age, gender, BMI, American Society of Anesthesiologists physical status classification, anemia, endstage renal disease, independence in performing activities of daily living, congestive heart failure, and pulmonary disease. The primary outcome of interest was the number of days between hospital admission and operative fixation, which we assessed using a Poisson regression and report as an incidence risk ratio. The secondary outcomes were the occurrences of major 30-day postoperative adverse events (failure to wean off mechanical ventilation, cerebrovascular events, renal failure, cardiovascular events, reoperation, death), minor 30-day adverse events (reintubation, wound complications, pneumonia, and thromboembolic events), and any 30-day adverse events (defined as the pooling of all adverse events, including readmissions). These outcomes were analyzed using a bivariate analysis and logistic regression with robust estimates of variance and are reported as odds ratios. Because any results on disparities rely on rigorous control of other baseline demographics, we performed this multivariable approach to ensure we were controlling for confounding variables as much as possible.

RESULTS

After controlling for potentially confounding variables such as age and gender, we found that Black patients had a longer mean wait time (incidence risk ratio 1.5 [95% CI 1.1 to 2.1]; p = 0.01) than white patients. After controlling for confounding variables, Black patients also had greater odds of having any postoperative adverse event (OR 2.1 [95% CI 1.1 to 3.8]; p = 0.02), including readmission (OR 3.3 [95% CI 1.5 to 7.6]; p = 0.004).

CONCLUSION

The racial disparities in pathologic long bone fracture care found in our study may be attributed to fundamental racial biases, as well as systemic socioeconomic disparities in the US healthcare system. Identifying and eliminating the racial, socioeconomic, and sociocultural biases that drive these disparities would improve care for patients with orthopaedic oncologic conditions. One possible way to reduce these disparities would be to implement standardized surgical care pathways for pathological long bone fractures across different institutions to minimize variation in important aspects of care, such as time to surgical fixation. Further insight is needed on the types of standardized care pathways and the implementation mechanisms that are most effective.

LEVEL OF EVIDENCE

Level III, therapeutic study.

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.

Effectiveness of Physical Activity Intervention on ADHD Symptoms: A Systematic Review and Meta-Analysis

Objective: To assess the effectiveness of physical activity (PA) intervention on attention-deficit/hyperactivity disorder (ADHD)-related symptoms. Method: Studies that investigated PA intervention for ADHD-related symptoms were identified through searching PubMed, Web of Science, Cochrane Library, and Embase databases from inception through June 2021. Standardized mean difference (SMD) with 95% confidence interval (CI) was used to assess the effectiveness of PA intervention on improving ADHD-related symptoms. The meta-analyses were conducted using fixed-effect or random-effect models according to the heterogeneity of the studies. Results: Nine before-after studies (232 participants) and 14 two-group control studies (162 participants/141 controls) were included in this meta-analysis. Combined results for before-after studies indicated significant improvements on all studied ADHD-related symptoms (inattention: SMD = 0.604, 95% CI: 0.374-0.834, p < 0.001; hyperactivity/impulsivity: SMD = 0.676, 95% CI: 0.401-0.950, p < 0.001; emotional problems: SMD = 0.416, 95% CI: 0.283-0.549, p < 0.001; behavioral problems: SMD = 0.347, 95% CI: 0.202-0.492, p < 0.001). Meta-analyses for two-group control studies further confirmed that PA intervention significantly improved the inattentive symptom (SMD = 0.715, 95% CI: 0.105, 1.325, p = 0.022). Subgroup analyses suggested significant beneficial effect on inattention symptoms in children. Moreover, closed motor skills were beneficial for hyperactive/impulsive problems (SMD = 0.671, p < 0.001), while open motor skills were beneficial for attention problems (SMD = 0.455, p = 0.049). When excluding studies with combined medication, the studies in unmedicated participants in before-after studies still showed significant results in all studied ADHD-related symptoms as in the overall analysis. Given the limited sample size, the best frequency and intensity of PA intervention need further investigation. Conclusion: Our results suggested that PA intervention could possibly improve ADHD-related symptoms, especially inattention symptoms. Closed-skill and open-skill activities could be beneficial for hyperactivity/impulsivity and inattention symptoms, respectively. Further high-quality randomized clinical trials with large sample size are needed.

A systematic review and meta-analysis of the pronator quadratus repair following volar plating of distal radius fractures

BACKGROUND

Distal radius fracture (DRF) is the most common upper extremity fracture that requires surgery. Operative treatment with a volar locking plate has proved to be the treatment of choice for unstable fractures. However, no consensus has been reached about the benefits of pronator quadratus (PQ) repair after volar plate fixation of DRF in terms of patient-reported outcome measures, pronation strength, and wrist mobility.

METHODS

We searched the PubMed, Embase, Cochrane Central, and China National Knowledge Infrastructure (CNKI) databases up to March 13, 2020, and included randomized-controlled, non-randomized controlled, or case-control cohort studies that compared cases with and without PQ repair after volar plate fixation of DRF. We used a random-effects model to pool effect sizes, which were expressed as standardized mean differences (SMDs) and 95% confidence intervals. The primary outcomes included Disabilities of the Arm, Shoulder, and Hand scores and pronation strength. The secondary outcomes included the SMDs in pain scale score, wrist mobility, and grip strength. The outcomes measured were assessed for publication bias by using a funnel plot and the Egger regression test.

RESULTS

Five randomized controlled studies and six retrospective case-control studies were included in the meta-analysis. We found no significant difference in primary and secondary outcomes at a minimum of 6-month follow-up. In a subgroup analysis, the pronation strength in the PQ repair group for AO type B DRFs (SMD = - 0.94; 95% CI, - 1.54 to - 0.34; p < 0.01) favored PQ repair, whereas that in the PQ repair group for non-AO type B DRFs (SMD = 0.39; 95% CI, 0.07-0.70; p = 0.02) favored no PQ repair.

DISCUSSION

We found no functional benefit of PQ repair after volar plate fixation of DRF on the basis of the present evidence. However, PQ muscle repair showed different effects on pronation strength in different groups of DRFs. Future studies are needed to confirm the relationship between PQ repair and pronation strength among different patterns of DRF.

REGISTRATION

This study was registered in the PROSPERO registry under registration ID No. CRD42020188343 .

LEVEL OF EVIDENCE

Therapeutic III.

Development and external validation of an MRI-based radiomics nomogram for pretreatment prediction for early relapse in osteosarcoma: A retrospective multicenter study

PURPOSE

To develop and externally validate an MR-based radiomics nomogram from retrospective multicenter datasets for pretreatment prediction of early relapse (≤ 1 year) in osteosarcoma after surgical resection.

METHODS

This multicenter study retrospectively enrolled 93 patients (training cohort: 62 patients from four hospitals; validation cohort: 31 patients from two hospitals) with clinicopathologically confirmed osteosarcoma who received neoadjuvant chemotherapy and surgical resection at six hospitals between January 2009 and October 2017. Radiomics features were extracted from contrast-enhanced fat-suppressed T1-weighted (CE FS T1-w) images. Least absolute shrinkage and selection operator (LASSO) regression was applied for feature selection and radiomics signature construction. The radiomics nomogram that incorporated the radiomics signature and subjective MRI-assessed candidate predictors was developed to predict early relapse with a multivariate logistic regression model in the training cohort and validated in the external validation cohort. The performance of the nomogram was assessed by its discrimination, calibration, and clinical usefulness.

RESULTS

The radiomics signature comprised six selected features and achieved favorable prediction efficacy. The radiomics nomogram incorporating the radiomics signature and subjective MRI-assessed candidate predictors (joint invasion and perivascular involvement) from the multicenter datasets achieved better discrimination in the training cohort (C-index：0.907, 95 % CI: 0.838-0.977) and external validation cohort (C-index: 0.811, 95 % CI: 0.653-0.970), and good calibration. Decision curve analysis suggested that the combined nomogram was clinically useful.

CONCLUSION

The proposed MRI-based radiomics nomogram could provide a non-invasive tool to predict early relapse of osteosarcoma, which has the potential to improve personalized pretreatment management of osteosarcoma.

Pathological Fracture and Prognosis of High-Grade Osteosarcoma of the Extremities: An Analysis of 2,847 Consecutive Cooperative Osteosarcoma Study Group (COSS) Patients

PURPOSE

The objective of this study was to investigate potential correlations between pathologic fractures (PFs) and prognosis of patients with primary central high-grade osteosarcoma of the extremities.

METHODS

We retrospectively analyzed 2,847 patients registered in the Consecutive Cooperative Osteosarcoma Study Group database with primary central high-grade osteosarcoma of the extremities, treated between 1980 and 2010. Intended treatment included pre- and postoperative chemotherapy and surgery. Univariable and multivariable survival analyses were performed for all patients and then differentiated for adult and pediatric (≤ 18 years at time of diagnosis) patients.

RESULTS

A total of 2,193 patients were ≤ 18 years of age; 11.3% of all patients had PFs. In the overall cohort, presence of PF correlated significantly with tumor site, histologic subtype, relative tumor size, and primary metastases, but not with body mass index or local surgical remission. In univariable analysis, 5-year overall survival (OAS) of patients with and without PF was 63% versus 71%, respectively (P = .007), and 5-year event-free survival (EFS) was 51% versus 58% (P = .026). In pediatric patients, OAS and EFS did not differ significantly between patients with and without PF. In adults, 5-year OAS in patients with and without PF was 46% versus 69% (P < .001), and 5-year EFS was 36% versus 56% (P < .001). In multivariable analysis, PF was not a statistically significant factor for OAS or EFS in the total cohort or in pediatric patients. In adult patients, PF remained an independent prognostic factor for OAS (P = .013; hazard ratio [HR], 1.893). It was not a significant prognostic factor for EFS (P = .263; HR, 1.312).

CONCLUSION

In this largest study to date with extremity osteosarcomas, we observed the occurrence of PF to correlate with inferior OAS expectancies in adult but not in pediatric patients.

MicroRNA-939-5p directly targets IGF-1R to inhibit the aggressive phenotypes of osteosarcoma through deactivating the PI3K/Akt pathway

The dysregulation of microRNA‑939‑5p (miR‑939) is involved in the development of multiple types of human cancer. However, the expression and roles of miR‑939 in osteosarcoma (OS) have yet to be clarified. The expression level of miR‑939 in OS was measured using reverse transcription quantitative polymerase chain reaction (RT‑qPCR). A Cell Counting Kit‑8 assay, flow cytometry analysis, Transwell migration and invasion assays, and a tumor xenograft assay were employed to explore the effects of miR‑939 in OS cells. Bioinformatics analysis, RT‑qPCR, western blot analysis and luciferase reporter assays were performed to explore its underlying mechanism. Expression of miR‑939 was decreased in both OS tissues and cell lines. The decreased miR‑939 expression was notably correlated with clinical stage and distant metastasis in patients with OS, where low miR‑939 levels were correlated with lower overall survival. miR‑939 overexpression decreased OS cell proliferation, migration and invasion in vitro; induced cell apoptosis, and impaired tumor growth in vivo. Mechanistically, insulin‑like growth factor 1 receptor (IGF‑1R) was characterized as direct target gene of miR‑939 in OS. The tumor‑suppressing effects of miR‑939 in OS cells were imitated by IGF‑1R knockdown. In addition, exogenous IGF‑1R expression abolished the tumor suppressive roles of miR‑939 in OS cells. miR‑939 was implicated in the deactivation of the PI3K/Akt pathway in OS in vitro and in vivo through regulating IGF‑1R expression. The present study demonstrated that miR‑939 exerted tumor‑suppressing roles in the malignancy of OS cells by directly targeting IGF‑1R and inactivating the PI3K/AKT pathway. Therefore, this miRNA may be a promising target for anticancer therapy in patients with OS.

Clinical and Molecular Analysis of Pathologic Fracture-associated Osteosarcoma: MicroRNA profile Is Different and Correlates with Prognosis

BACKGROUND

MicroRNAs are small, noncoding RNAs that regulate the expression of posttranslational genes. The presence of some specific microRNAs has been associated with increased risk of both local recurrence and metastasis and worse survival in patients with osteosarcoma. Pathologic fractures in osteosarcoma are considered to be more the manifestation of a neoplasm with a more aggressive biological behavior than the cause itself of worse prognosis. However, this has not been proved at the biological or molecular level. Currently, there has not been a microRNA profiling study of patients who have osteosarcoma with and without pathologic fractures that has described differences in terms of microRNA profiling between these two groups and their correlation with biologic behavior.

QUESTIONS/PURPOSES

(1) In patients with osteosarcoma of the extremities, how do the microRNA profiles of those with and without pathologic fractures compare? (2) What relationship do microRNAs have with local recurrence, risk of metastasis, disease-specific survival, and overall survival in osteosarcoma patients with pathologic fractures?

METHODS

Between 1994 and 2013, 217 patients were diagnosed and treated at our institution for osteosarcoma of the extremities. Patients were excluded if (1) they underwent oncologic resection of the osteosarcoma at an outside institution (two patients) or (2) they were diagnosed with an extraskeletal osteosarcoma (29 patients) or (3) they had less than 1 year of clinical follow-up and no oncologic outcome (local recurrence, metastasis, or death) (four patients). A total of 182 patients were eligible. Of those, 143 were high-grade osteosarcomas. After evaluation of tumor samples before chemotherapy treatment, a total of 80 consecutive samples were selected for sequencing. Demographic and clinical comparison between the sequenced and non-sequenced patients did not demonstrate any differences, confirming that both groups were comparable. Diagnostic samples from the extremities of 80 patients with high-grade extremity osteosarcomas who had not yet received chemotherapy underwent microRNA sequencing for an ongoing large-scale osteosarcoma genome profiling project at our institution. Six samples were removed after a second look by a musculoskeletal pathologist who verified cellularity and quality of samples to be sequenced, leaving a total of 74 patients. Of these, two samples were removed as they were confirmed to be pelvic tumors in a second check after sequencing. The final study sample was 72 patients (11 patients with pathologic fractures and 61 without). Sequencing data were correlated with fractures and local recurrence, risk of metastasis, disease-specific survival, and overall survival through Kaplan-Meier analyses.

RESULTS

Several microRNAs were expressed differently between the two groups. Among the markers with the highest differential expression (edgeR and DESeq algorithms), Hsa-mIR 656-3p, hsa-miR 493-5p, and hsa-miR 381-3p were upregulated in patients with pathologic fractures, whereas hsa-miR 363, hsa-miR 885-5p, and has-miR 20b-5p were downregulated. The highest differential expression fracture and nonfracture-associated microRNA markers also distinguished groups of patients with different metastasis risk, a well as different disease-specific and overall survival. Furthermore, the profile of pathologic fractures demonstrated a higher differential expression for microRNA markers that were previously associated with a higher risk of metastasis and lower survival rates in patients with osteosarcoma.

CONCLUSIONS

In patients who have osteosarcoma, the microRNA profiles of those with pathologic fractures are different than of patients without pathologic fractures. The highest differential expression mircroRNA molecules in patients with pathologic fractures predict also higher risk of metastatic disease as well as worse disease-specific survival and overall survival. Furthermore, we found higher differential expression of microRNAs in the pathologic fracture group previously associated with poor prognosis. The higher risk of metastasis and poorer overall survival in patients with pathologic fractures is inherent to tumor aggressive biologic behavior. It is plausible that the fracture itself is not the direct cause of worse prognosis but another manifestation of tumor biologic aggressiveness. Identification of these molecules through liquid biopsies may help to determine which patients may benefit from surgery before fractures occur. The same technology can be applied to identify patterns of response to conventional chemotherapy, assisting in more specific and accurate systemic therapy.

LEVEL OF EVIDENCE LEVEL

III, prognostic study.

Increased risk of pelvic fracture after radiotherapy in rectal cancer survivors: A propensity matched study

To determine whether radiotherapy (RT) can increase pelvic fracture risk in rectal cancer survivors. Rectal cancer patients who underwent curative surgery between 1996 and 2011 in Taiwan were retrospectively studied using the National Health Insurance Research Database (NHIRD) of Taiwan. ICD‐9 Codes 808, 805.4‐805.7, 806.4‐806.7, and 820 (including pelvic, sacrum, lumbar, and femoral neck fracture) were defined as pelvic fracture. Propensity scores for RT, age, and sex were used to perform one‐to‐one matches between the RT and non‐RT group. Risks of pelvic and arm fractures were compared by multivariable Cox regression. Of the 32 689 patients, 7807 (23.9%) received RT, and 1616 suffered from a pelvic fracture (incidence rate: 1.17/100 person‐years). The median time to pelvic fracture was 2.47 years. After matching, 6952 patients each in the RT and non‐RT groups were analyzed. RT was associated with an increased risk of pelvic fractures in the multivariable Cox model (hazard ratio (HR): 1.246, 95% confidence interval (CI): 1.037‐1.495, P = 0.019) but not with arm fractures (HR: 1.013, 95% CI: 0.814‐1.259, P = 0.911). Subgroup analyses revealed that RT was associated with a higher pelvic fracture rate in women (HR: 1.431, 95% CI: 1.117‐1.834) but not in men, and the interaction between sex and RT was significant (P = 0.03). The HR of pelvic fracture increased 2‐4 years after RT (HR: 1.707, 95% CI: 1.150‐2.534, P = 0.008). An increased risk of pelvic fracture is noted in rectal cancer survivors, especially women, who receive RT.

MiR-409-3p Inhibits Cell Proliferation and Invasion of Osteosarcoma by Targeting Zinc-Finger E-Box-Binding Homeobox-1

Osteosarcoma (OS) is the most common bone cancer worldwide. There is evidence that microRNA-409 (miR-409-3p) is involved in tumorigenesis and cancer progression, however, its possible role in OS requires clarification. In the present study, we evaluated the expression level, clinical significance, and mode of action of miR-409-3p in OS. The miR-409-3p levels were diminished in the OS cells and tissues compared with associated adjacent non-tumor tissues and a non-cancer osteoplastic cell line. Low miR-409-3p expression levels were associated with clinical stage and distant metastasis in patients with OS. Resumption of miR-409-3p expression attenuated OS cell proliferation and invasion. Additionally, based on informatics analyses, we predicted that zinc-finger E-box-binding homeobox-1 (ZEB1) is a possible target of miR-409-3p. This hypothesis was confirmed using luciferase reporter assays, reverse transcription-quantitative real-time polymerase chain reaction, and Western blot analyses. The findings of the current study indicated that ZEB1 was up-regulated in the OS tissues and cell lines, and that this up-regulation was inversely proportional to miR-409-3p expression levels. Furthermore, down-regulation of ZEB1 decreased OS cell invasion and proliferation, illustrating that the tumor suppressive role of miR-409-3p in OS cells may be exerted via negative regulation of ZEB1. Taken together, our observations highlight the potential role of miR-409-3p as a tumor suppressor in OS partially through down-regulation of ZEB1 and suggest that miR-409-3p has potential applications in OS treatment.

Clinical epidemiology and treatment outcomes of spindle cell non-osteogenic bone sarcomas - A nationwide population-based study

Purpose

To describe epidemiological and clinical characteristics, as well as long-term treatment outcomes of spindle cell non-osteogenic bone sarcomas (SCS), comprising leiomyosarcoma, fibrosarcoma and undifferentiated pleomorphic sarcoma in bone.

Method

We have analysed a nationwide cohort of 104 patients with histologically verified SCS diagnosed between 1975 and 2009, based on registry sources supplemented with clinical records from Norwegian hospitals involved in sarcoma management.

Results

In this unselected cohort, a stable annual incidence for SCS patients of slightly below 0.6 per million was observed, with a dominant peak among elderly patients. SCS is mostly a high-grade malignancy (92%) with a male to female ratio of 1.6 for all patients. The axial to appendicular ratio was 0.7, seemingly independent of age. More than one fourth of the patients (29%) had primary metastatic disease. Another 32 patients (46%) developed metastases during follow-up and 12 (17%) experienced local relapses. The five-year sarcoma-specific survival rate was 37%, with no documented improvement over time. Primary metastatic disease was an adverse prognostic factor for survival. Predisposing factors were documented in 19 patients (18%). Negative prognostic factors for overall survival were tumour size >9 cm, age > 40 years, axial tumour localization, FS as subtype and pathologic fracture at time of diagnoses. As expected, patients who received both surgery and chemotherapy as their primary treatment for high-grade SCS (25%) significantly had best sarcoma specific five years survival (62%).

Conclusion

We confirm SCS as a rare high-grade bone sarcoma entity, mostly among elderly patients and with a poor overall outcome. The combined treatment of surgery and chemotherapy is essential to achieve optimal long-term survival of SCS.

Impact of Pathological Fractures on the Prognosis of Primary Malignant Bone Sarcoma in Children and Adults: A Single-Center Retrospective Study of 205 Patients

BACKGROUND

The purpose of this study was to investigate whether pathological fractures (PF) influence the prognosis of patients with osteosarcoma (OS) or Ewing tumor (ET) regarding 5-year survival, occurrence of metastases, and local recurrence.

METHODS

We retrospectively analyzed 205 patients with metastatic and nonmetastatic OS or ET. Survival analysis was performed for all patients and differentiated for patients with OS (n = 127) and ET (n = 78) as well as for adults (n = 101) and children (n = 104).

RESULTS

Patients with PF showed survival rates of 64% compared to 83% for those without PF (p = 0.023). Local recurrence occurred in 7% of the patients without and in 24% of those with PF (p = 0.023). In patients with ET and in children, survival analysis showed no significant difference between patients with and without PF in survival and local recurrence rates. In patients with OS, survival rate decreased from 83 to 59% (p = 0.024) and local recurrence rate increased from 13 to 30% (p = 0.042). In adults, survival rate decreased from 78 to 51% (p = 0.004) and local recurrence rate increased from 13 to 42% (p < 0.001). In multivariate analysis, age and PF were associated with inferior survival.

CONCLUSION

This study suggests that the occurrence of PF has a negative impact on survival and implicates an increased risk of local recurrence. In children and in patients with ET, PF did not have a prognostic impact.

Long Noncoding RNA LINC01133 Functions as an miR-422a Sponge to Aggravate the Tumorigenesis of Human Osteosarcoma

Long noncoding RNAs (lncRNAs) have been verified to participate in various types of malignant tumors, including osteosarcoma (OS), which is the most common primary bone tumor with outstanding morbidity. Although an increasing number of lncRNAs have been reported to mediate the occurrence of OS, the potential mechanisms are still unclear. This study intends to uncover the mechanism by which lncRNA LINC01133 functions as an miRNA sponge to mediate OS tumorigenicity. In this study, we found that the expression level of LINC01133 was statistically upregulated in OS tumor tissue and cell lines compared to noncancerous tissues and a normal human osteoplastic cell line. LINC01133 silencing could also observably suppress the proliferation, migration, and invasion of OS cells (HOS and U2-OS). Bioinformatics analysis predicted that LINC01133 specifically targeted miR-422a, which was validated by dual-luciferase reporter assay. Furthermore, functional experiments revealed that miR-422a played a tumor-suppressive role in OS progression and could effectively reverse the function of LINC01133. In summary, our study discovered that lncRNA LINC01133 aggravates the proliferation, migration, and invasion of OS by sponging miR-422a, which provides a novel insight in the tumorigenesis of OS.

Survival and prognostic factors at time of diagnosis in high-grade appendicular osteosarcoma: a 21 year single institution evaluation from east Denmark

BACKGROUND

Survival of patients with high-grade osteosarcoma (HOS), the most common primary bone cancer, has not improved significantly the last 30 years and the disease remains a major challenge. The purpose of this study is to evaluate survival in relation to prognostic factors at time of diagnosis among patients diagnosed with primary appendicular HOS in East Denmark between 1990 and 2010.

MATERIAL AND METHODS

101 patients (median age = 20 years, female/male ratio = 56/45) diagnosed with primary appendicular high-grade osteosarcoma between 1990 and 2010 were included in this study. Initially, 156 patients diagnosed with osteosarcoma between 1990 and 2010 were identified through the population based Regional Database of Pathology, which covers a population of approximately 2.7 million (east Denmark). 55 patients were excluded due to (A) tumor was low grade (n = 22), (B) located in axial skeleton (n = 18), (C) incorrect diagnosis (n = 11) or (D) biopsy represented a tumor relapse from a former primary osteosarcoma (n = 4). Overall survival was evaluated using the Kaplan-Meier survival analysis and log-rank test. Prognostic factors were analyzed using uni- and multivariate cox-regression method with variables scored equally in the model. p Values <.05 were considered statistically significant.

RESULTS

The probability of 5- and 10-year survival was 51% (95% CI: 41-61) and 46% (95% CI: 36-56), respectively. Metastatic stage at diagnosis and tumor size ≥10 cm measured radiologically at the largest diameter were independent prognostic factors for decreased survival with significant increased hazard-risks of 3.5 (95% CI: 1.9-6.5) and 1.97 (95% CI: 1.1-3.6), respectively.

DISCUSSION

In this single institution evaluation of primary appendicular HOS we found 5-and 10-year survival rates consistent with international standards for this patient group. Distant metastases and tumor size ≥10 cm at the time of diagnosis were independent prognostic factors for decreased survival in our cohort. These results underline the importance of awareness and early referral from the primary sector.

MicroRNA‑302a suppresses cell proliferation, migration and invasion in osteosarcoma by targeting ADAM9

Osteosarcoma (OS) is the most frequent malignant primary bone tumor arising from primitive bone‑forming mesenchymal cells in children and adolescents. The dysregulation of microRNAs (miRNAs) has been reported in OS, and these aberrantly expressed miRNAs are involved in the initiation and progression of OS. The aim of the present study was to investigate the expression and functions of miRNA‑302a (miR‑302a) in OS and its underlying mechanism. It was found that the expression of miR‑302a was reduced in OS tissues and cell lines. The low expression of miR‑302a was significantly correlated with tumor‑node‑metastasis stage and metastasis. The ectopic overexpression of miR‑302a inhibited the proliferation, migration and invasion of OS cells. Bioinformatics analysis showed that a disintegrin and metalloproteinase 9 (ADAM9) was a potential target gene of miR‑302a. Subsequently, reverse transcription‑quantitative polymerase chain reaction and western blot analyses revealed that miR‑302a regulated the expression of ADAM9 at the post‑transcriptional level in OS cells. In addition, a luciferase reporter assay demonstrated that miR‑302a directly targeted the 3'untranslated region of ADAM9. In clinical OS tissues, the mRNA expression of ADAM9 was upregulated and inversely correlated with the expression of miR‑302a. In addition, the effects of ADAM9 knockdown on cell proliferation, migration and invasion were similar to those induced by the overexpression of miR‑302a in OS cells. These findings suggested that miR‑302a inhibited OS cell growth and metastasis by targeting ADAM9. miR‑302a may serve as a potential therapeutic target for patients with OS.

Can a Bayesian Belief Network Be Used to Estimate 1-year Survival in Patients With Bone Sarcomas?

BACKGROUND

Extremity sarcoma has a preponderance to present late with advanced stage at diagnosis. It is important to know why these patients die early from sarcoma and to predict those at high risk. Currently we have mid- to long-term outcome data on which to counsel patients and support treatment decisions, but in contrast to other cancer groups, very little on short-term mortality. Bayesian belief network modeling has been used to develop decision-support tools in various oncologic diagnoses, but to our knowledge, this approach has not been applied to patients with extremity sarcoma.

QUESTIONS/PURPOSES

We sought to (1) determine whether a Bayesian belief network could be used to estimate the likelihood of 1-year mortality using receiver operator characteristic analysis; (2) describe the hierarchal relationships between prognostic and outcome variables; and (3) determine whether the model was suitable for clinical use using decision curve analysis.

METHODS

We considered all patients treated for primary bone sarcoma between 1970 and 2012, and excluded secondary metastasis, presentation with local recurrence, and benign tumors. The institution's database yielded 3499 patients, of which six (0.2%) were excluded. Data extracted for analysis focused on patient demographics (age, sex), tumor characteristics at diagnosis (size, metastasis, pathologic fracture), survival, and cause of death. A Bayesian belief network generated conditional probabilities of variables and survival outcome at 1 year. A lift analysis determined the hierarchal relationship of variables. Internal validation of 699 test patients (20% dataset) determined model accuracy. Decision curve analysis was performed comparing net benefit (capped at 85.5%) for all threshold probabilities (survival output from model).

RESULTS

We successfully generated a Bayesian belief network with five first-degree associates and describe their conditional relationship with survival after the diagnosis of primary bone sarcoma. On internal validation, the resultant model showed good predictive accuracy (area under the curve [AUC] = 0.767; 95% CI, 0.72-0.83). The factors that predict the outcome of interest, 1-year mortality, in order of relative importance are synchronous metastasis (6.4), patient's age (3), tumor size (2.1), histologic grade (1.8), and presentation with a pathologic fracture (1). Patient's sex, tumor location, and inadvertent excision were second-degree associates and not directly related to the outcome of interest. Decision curve analysis shows that clinicians can accurately base treatment decisions on the 1-year model rather than assuming all patients, or no patients, will survive greater than 1 year. For threshold probabilities less than approximately 0.5, the model is no better or no worse than assuming all patients will survive.

CONCLUSIONS

We showed that a Bayesian belief network can be used to predict 1-year mortality in patients presenting with a primary malignancy of bone and quantified the primary factors responsible for an increased risk of death. Synchronous metastasis, patient's age, and the size of the tumor had the largest prognostic effect. We believe models such as these can be useful as clinical decision-support tools and, when properly externally validated, provide clinicians and patients with information germane to the treatment of bone sarcomas.

CLINICAL RELEVANCE

Bone sarcomas are difficult to treat requiring multidisciplinary input to strategize management. An evidence-based survival prediction can be a powerful adjunctive to clinicians in this scenario. We believe the short-term predictions can be used to evaluate services, with 1-year mortality already being a quality indicator. Mortality predictors also can be incorporated in clinical trials, for example, to identify patients who are least likely to experience the side effects of experimental toxic chemotherapeutic agents.

Pathologic fracture in childhood and adolescent osteosarcoma: A single-institution experience

PURPOSE

Pathologic fractures occur in 5-10% of pediatric osteosarcoma (OS) cases and have historically been considered a contraindication to limb salvage. Our purpose was to describe the radiographic features of pathologic fracture and examine its impact on local recurrence rates, functional outcomes, and overall survival.

METHODS

We retrospectively analyzed patients at our institution from 1990 to 2015 with pathologic fracture at diagnosis or during neoadjuvant chemotherapy. We selected a control group of 50 OS patients of similar age and gender without pathologic fracture from 1990 to 2015. Functional outcomes were scored using Musculoskeletal Tumor Society criteria. Chi-square test was used for comparative analysis of groups.

RESULTS

Thirty-six patients with 37 pathologic fractures form the study cohort. Of patients who received surgery, 18 of 34 patients with fracture underwent amputation compared to 8 of 48 patients in the nonfracture group (P = 0.007). Indications for amputation in fracture patients were tumor size (n = 7), neurovascular involvement (n = 6), and tumor progression during neoadjuvant chemotherapy (n = 5). Only one patient (2.9%) in the fracture group who underwent limb salvage suffered local recurrence. Of patients who received neoadjuvant chemotherapy, 25 of 34 fracture patients showed poor histological response compared to 24 of 47 nonfracture patients (P = 0.044). There was no statistically significant difference in overall survival (P = 0.96). Functional outcomes were significantly lower in fracture patients (median = 17.5) than nonfracture patients (median = 24) (P = 0.023).

CONCLUSIONS

Radiographic features of pathologic fractures were highly variable in this population. Limb salvage surgery can be performed without increased risk of local recurrence. Patients with pathologic fracture suffer worse functional outcomes but no decrease in overall survival.

Update on Survival in Osteosarcoma

Osteosarcoma is the most common primary bone malignancy in children. Treatment has evolved to include systemic chemotherapy and local control surgery. Although survival improved initially in a drastic fashion with this approach, recent decades have seen little to no further gains in this area. Limb salvage surgery evolved with effective chemotherapy and advances in imaging, and continues to improve in the recent era. This article serves as a review of survival in high-grade osteosarcoma: prognostic factors, advances in chemotherapy and surgery, late effects of chemotherapy and surgery in survivors, and future directions.

Prognostic value of IGF-1R expression in bone and soft tissue sarcomas: a meta-analysis

Accumulated evidence has indicated a correlation between IGF-1R and bone and soft tissue sarcoma (BSTS) progression. However, research on the prognostic role of IGF-1R in sarcomas has revealed very different or even totally opposite results. This meta-analysis aimed to unveil the controversial role IGF-1R plays in predicting the outcome of BSTS patients. We systematically reviewed the evidence for the effect of IGF-1R expression in multiple types of BSTSs, including osteosarcoma, Ewing’s sarcoma, synovial sarcoma, liposarcoma, and rhabdomyosarcoma, to elucidate this issue. The prognostic value of IGF-1R expression in BSTS patients was evaluated regarding overall survival, measured by pooled hazard ratios (HRs) with 95% confidence intervals (CIs). Seven studies including 627 patients were enrolled in this meta-analysis. Our results demonstrated that IGF-1R expression was associated with poor outcome in terms of overall survival in BSTS patients (pooled HR =2.15, 95% CI: 1.06–4.38; P=0.03). In subtypes of BSTSs, elevated IGF-1R expression was revealed to be significantly correlated with worse prognosis in osteosarcoma (pooled HR =2.20, 95% CI: 1.59–0.03; P<0.001), while no statistical significance was discovered in Ewing’s sarcoma (pooled HR =1.01, 95% CI: 0.45–2.27; P=0.99). Expression of IGF-1R could be a negative prognostic biomarker for patients suffering from BSTSs.

The Functional Role of PMP22 Gene in the Proliferation and Invasion of Osteosarcoma

Background

As the most common primary bone tumor, osteosarcoma has an improved survival rates with advancement of treatment methods. A higher rate of metastasis, however, leads to the aggravation of the disease. Studies have shown that some genes, namely osteosarcoma metastasis-related genes, participate in the process of tumor metastasis. The peripheral myelin protein 22 (PMP22) gene has recently been found to be abundantly expressed in the oncogenesis of osteosarcoma. Its detailed role and function in the tumor metastasis, however, remains unknown.

Material/Methods

The recombinant retroviral plasmid pcDNA3.1-PMP22 was constructed and used to transfect osteosarcoma cells SOSP-M, whose cell proliferation was measured by MTT method. The formation of tumor cell colony, the cell migration and invasion were also measured. The signal transduction pathway MAPK was further analyzed by Western blotting.

Results

The pcDNA3.1-PMP22 plasmid was confirmed to have a 305bp PMP22 fragment by EcoRI-XhoI dual digestion. Compared to the control group, osteosarcoma cell invasion was significantly facilitated by the transfection of pcDNA3.1-PMP22 plasmid (p<0.05). The recombinant plasmid also significantly potentiated the formation of tumor cell colony and increased the migration and invasion ability of tumor cells (p<0.05 in all cases). Phosphorylated p-ERK and p-P38 were also up-regulated by vector transfection (p<0.05).

Conclusions

Osteosarcoma metastasis-related gene PMP22 participates in the proliferation, invasion, migration and colony formation of osteosarcoma cells possibly via the MAPK signal transduction pathway, providing evidences for further investigation of metastatic mechanism of osteosarcoma.

Nanosecond pulsed electric field inhibits proliferation and induces apoptosis in human osteosarcoma

OBJECTIVE

Recent studies suggest that nanosecond pulsed electric field (nsPEF) is a novel minimal invasive and non-thermal ablation method that can induce apoptosis in different solid tumors. But the efficacy of nsPEF on bone-related tumors or bone metastasis is kept unknown. The current study investigates antitumor effect of nsPEF on osteosarcoma MG-63 cells in vitro.

METHOD

MG-63 cells were treated with nsPEF with different electric field strengths (0, 10, 20, 30, 40, and 50 kV/cm) and different pulse numbers (0, 6, 12, 18, 24, and 30 pulses). The inhibitory effect of nsPEF on the growth of MG-63 cells was measured by Cell Counting Kit-8 (CCK-8) assay at different time points (0, 3, 12, 24, and 48 h post nsPEF treatment). The apoptosis was analyzed by Hoechst stain, in situ terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL), and flow cytometric analysis. The expression of osteoprotegerin (OPG), receptor activator of NF-κB ligand (RANKL), and tumor necrosis factor α (TNF-α) was examined by reverse-transcription polymerase chain reaction (RT-PCR) and western blot.

RESULTS

The CCK-8 assay showed that nsPEF induced a distinct electric field strength- and pulse number-dependent reduction of cell proliferation. For treatment parameter optimizing, the condition 40 kV/cm and 30 pulses at 24 h post nsPEF achieved the most significant apoptotic induction rate. Hoechst, TUNEL, and flow cytometric analysis showed that the cell apoptosis was induced and cells were arrested in the G0/G1 phase. PCR and western blot analysis demonstrated that nsPEF up-regulated OPG expression had no effect on RANKL, increased OPG/RANKL ratio.

CONCLUSION

NsPEF inhibits osteosarcoma growth, induces apoptosis, and affects bone metabolism by up-regulating OPG, indicating nsPEF-induced apoptosis in osteosarcoma MG-63 cells. NsPEF has potential to treat osteosarcoma or bone metastasis. When nsPEF is applied on metastatic bone tumors, it might be beneficial by inducing osteoblastic differentiation without cancer proliferation. In the future, nsPEF might be one of the treatments of metastatic bone tumor.