Grade of chemotherapy-induced necrosis as a predictor of local and systemic control in 881 patients with non-metastatic osteosarcoma of the extremities treated with neoadjuvant chemotherapy in a single institution

Tumor necrosis drives prognosis in osteosarcoma: No difference in chemotherapy response and survival between chondroblastic and osteoblastic osteosarcoma

INTRODUCTION

The percentage of tumor necrosis is a crucial prognostic factor in osteosarcoma. Many studies adopt a 90 % cutoff based on osteoblastic osteosarcoma, but these findings are generalized to all conventional subtypes, including chondroblastic osteosarcoma. We sought to answer these questions: (1) Is tumor necrosis ≥90 % associated with better overall survival (OS) and disease-free survival (DFS) in osteoblastic and chondroblastic osteosarcoma? (2) Does the osteosarcoma subtype impact tumor necrosis? (3) Does the osteosarcoma subtype in "good" responders (tumor necrosis ≥90 %) affect OS and DFS?.

MATERIALS AND METHODS

We conducted a retrospective study of 156 patients with osteoblastic and chondroblastic osteosarcoma treated at our institution. All patients received a standardized chemotherapy protocol and underwent surgery with the goal of achieving negative margins (R0 resection). Propensity-score matching was performed to adjust for potential confounders. Kaplan-Meier survival analysis and Cox proportional hazards modeling were performed.

RESULTS

Patients with osteoblastic osteosarcoma and tumor necrosis ≥90 % had higher 5- and 10-year OS and DFS compared to those with necrosis <90 %. In chondroblastic osteosarcoma, a trend towards higher OS and DFS was seen in patients with tumor necrosis ≥90 %; this, however, was not significant. Chondroblastic osteosarcoma was not a risk factor for either tumor necrosis <90 % (p = 0.89) or tumor necrosis <70 % (p = 0.57). Patients with osteoblastic or chondroblastic osteosarcoma that were deemed "good" responders (tumor necrosis ≥90 %) had similar OS and DFS at the 5- and 10-year marks.

CONCLUSION

Conventional osteosarcoma subtype was not a risk factor for "poor" response. Survival outcomes (OS and DFS) were similar for osteoblastic and chondroblastic osteosarcoma with good response to chemotherapy.

The role of imaging in extremity sarcoma surgery

The surgical management of extremity bone and soft tissue sarcomas has evolved significantly over the last 50 years. The introduction and refinement of high-resolution cross-sectional imaging has allowed accurate assessment of anatomy and tumor extent, and in the current era more than 90% of patients can successfully undergo limb-salvage surgery. Advances in imaging have also revolutionized the clinician's ability to assess treatment response, detect metastatic disease, and perform intraoperative surgical navigation. This review summarizes the broad and essential role radiology plays in caring for sarcoma patients from diagnosis to post-treatment surveillance. Present evidence-based imaging paradigms are highlighted along with key future directions.

The management of osteosarcoma in children and adolescents in a resource-limited setting: quality improvement considerations to improve treatment outcomes

BACKGROUND

The survival rates for children and adolescents with osteosarcoma in low-income countries are poor. Insufficient data regarding the challenges of managing osteosarcoma in resource-limited settings has been published. We evaluated the treatment of osteosarcoma in children and adolescents with the aim of improving the health system and management outcomes.

METHODS

We sourced data on children under 18 years treated for osteosarcoma at the Uganda Cancer Institute between January 2016 and December 2020. Descriptive statistics and Kaplan-Meier survival analysis were used.

RESULTS

Seventy-four osteosarcoma cases were identified, with a median age of 13 years (IQR 9.8-15). Referrals were made after a median of 28 days (range 1-147). Before appropriate referral, more than a quarter (26%) had undergone invasive procedures that could compromise tumour integrity and outcome. Half (50%) of the patients had metastatic disease at diagnosis, primarily to the lungs (n = 43; 92%). Only 14 (33%) patients received neoadjuvant chemotherapy. Forty-three (58.1%) patients underwent limb amputation surgery, including 25 localized tumours and 18 patients with distant metastatic disease. No metastatectomies were performed. Adjuvant chemotherapy was delayed for longer than 21 days in 26 (61%) patients. No pathology reports described the status of resection margins or the degree of chemotherapy-induced necrosis. Twenty-six (35%) patients abandoned treatment, mainly due to pending radical surgery (n = 18/26; 69%). Only 18% (n = 13) were still alive; 46% (n = 34) had died; and 37% (n = 27) had an unknown status. The median overall survival was 1.1 years, and was significantly negatively affected by disease metastasis, timing of adjuvant therapy, and treatment abandonment.

CONCLUSIONS

Osteosarcoma outcomes for children and adolescents at the Uganda Cancer Institute are extremely poor. The quality of care can be improved by addressing delayed referrals, high rates of prior manipulative therapy, metastatic disease, treatment abandonment, surgical challenges, and delayed resumption of adjuvant chemotherapy.

Cell Cycle Checkpoints p16 and p21-Strong Predictors of Clinicopathologic Outcomes in High-Grade Osteosarcoma

PURPOSE

In this study, we used a series of immunohistochemical measurements of 2 cell cycle regulators, p16 and p21, to evaluate their prognostic value, separately and in combination, for the disease outcomes.

METHOD

A total of 101 patients with high-grade osteosarcoma were included in this study. Clinicopathologic data were collected, and immunohistochemistry for p16 and p21 was performed and interpreted by 3 independent pathologists. Statistical analysis was performed to assess the strength of each of these markers relative to disease outcome.

RESULTS

Our results indicate that more than 90% expression (high) of p16 by immunohistochemistry on the initial biopsy has a strong predictive value for good histologic response to chemotherapy. The patients are also more likely to survive the past 5 years and less likely to develop metastasis than patients with less than 90% p16 (low) expression. The results for p21, on the other hand, show a unique pattern of relationship to the clinicopathologic outcomes of the disease. Patients with less than 1% (low) or more than 50% (high) expression of p21 by immunohistochemistry show a higher chance of metastasis, poor necrotic response to chemotherapy, and an overall decreased survival rate when compared with p21 expression between 1% and 50% (moderate). Our results also showed that the expression of p16 and combined p16 and p21 demonstrates a stronger predictive relationship to 5-year survival than tumor histologic necrosis and p21 alone.

DISCUSSION

The results of this study, once proven to be reproducible by a larger number of patients, will be valuable in the initial assessment and risk stratification of the patients for treatment and possibly the clinical trials.

Advantages and limitations of using cell viability assays for 3D bioprinted constructs

Bioprinting shows promise for bioengineered scaffolds and three-dimensional (3D) disease models, but assessing the viability of embedded cells is challenging. Conventional assays are limited by the technical problems that derive from using multi-layered bioink matrices dispersing cells in three dimensions. In this study, we tested bioprinted osteogenic bioinks as a model system. Alginate- or gelatin-based bioinks were loaded with/without ceramic microparticles and osteogenic cells (bone tumor cells, with or without normal bone cells). Despite demonstrating 80%-90% viability through manual counting and live/dead staining, this was time-consuming and operator-dependent. Moreover, for the alginate-bioprinted scaffold, cell spheroids could not be distinguished from single cells. The indirect assay (alamarBlue), was faster but less accurate than live/dead staining due to dependence on hydrogel permeability. Automated confocal microscope acquisition and cell counting of live/dead staining was more reproducible, reliable, faster, efficient, and avoided overestimates compared to manual cell counting by optical microscopy. Finally, for 1.2 mm thick 3D bioprints, dual-photon confocal scanning with vital staining greatly improved the precision of the evaluation of cell distribution and viability and cell-cell interactions through thez-axis. In summary, automated confocal microscopy and cell counting provided superior accuracy for the assessment of cell viability and interactions in 3D bioprinted models compared to most commonly and currently used techniques.

Imaging Assessment of the Efficacy of Chemotherapy in Primary Malignant Bone Tumors: Recent Advances in Qualitative and Quantitative Magnetic Resonance Imaging and Radiomics

Recent studies have shown that MRI demonstrates promising results for evaluating the chemotherapy efficacy in bone sarcomas. This article reviews current methods for evaluating the efficacy of malignant bone tumors and the application of MRI in this area, and emphasizes the advantages and limitations of each modality. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 2.

Solitary pulmonary metastases at first recurrence of osteosarcoma: Presentation, treatment, and survival of 219 patients of the Cooperative Osteosarcoma Study Group

BACKGROUND

To evaluate patient and tumour characteristics, treatment and their impact on survival in patients with a solitary pulmonary metastasis at first relapse of high-grade osteosarcoma.

PROCEDURE

Two-hundred and nineteen consecutive patients who had achieved a complete surgical remission and then developed a solitary pulmonary metastasis at first recurrence of high-grade osteosarcoma were retrospectively reviewed.

RESULTS

Two hundred and three (94.9%) of 214 patients achieved a second complete remission. After a median time from initial diagnosis of osteosarcoma to first relapse of 2.3 years (range, 0.3-18.8 years), actuarial post-relapse overall survival after 2 and 5 years was 72.0% and 51.2%. Post-relapse event-free survival was 39.1% and 31.1%. Median follow-up time was 3.2 years (range, 0.1-29.4 years). A longer time until first relapse and diagnosis due to imaging were positive prognostic factors in uni- and multivariate analyses, as were a second complete surgical remission and, in regard to death, the absence of a subsequent relapse. The use of salvage chemotherapy and radiotherapy were not associated with patient outcomes, nor was the surgical approach (thoracoscopy vs. thoracotomy) nor the exploration (uni- vs. bilateral).

CONCLUSION

Approximately half of the patients who experience a solitary pulmonary relapse at first recurrence of osteosarcoma remain alive 5 years after this first relapse. Only one third will remain disease-free. A complete surgical resection of the lesion is essential for long-term survival while relapse chemotherapy does not seem to improve survival. Innovative therapies are required to improve outcomes.

Transcriptional profiling of canine osteosarcoma identifies prognostic gene expression signatures with translational value for humans

Canine osteosarcoma is increasingly recognized as an informative model for human osteosarcoma. Here we show in one of the largest clinically annotated canine osteosarcoma transcriptional datasets that two previously reported, as well as de novo gene signatures devised through single sample Gene Set Enrichment Analysis (ssGSEA), have prognostic utility in both human and canine patients. Shared molecular pathway alterations are seen in immune cell signaling and activation including TH1 and TH2 signaling, interferon signaling, and inflammatory responses. Virtual cell sorting to estimate immune cell populations within canine and human tumors showed similar trends, predominantly for macrophages and CD8+ T cells. Immunohistochemical staining verified the increased presence of immune cells in tumors exhibiting immune gene enrichment. Collectively these findings further validate naturally occurring osteosarcoma of the pet dog as a translationally relevant patient model for humans and improve our understanding of the immunologic and genomic landscape of the disease in both species.

Identification of New Potential Prognostic and Predictive Markers in High-Grade Osteosarcoma Using Whole Exome Sequencing

Conventional high-grade osteosarcoma (OS) is the most common primary cancer of bone and it typically affects the extremities of adolescents. OS has a complex karyotype, and molecular mechanisms related to carcinogenesis, progression and resistance to therapy are still largely unknown. For this reason, the current standard of care is associated with considerable adverse effects. In this study, our aim was to identify gene alterations in OS patients using whole exome sequencing (WES) to find new potential prognostic biomarkers and therapeutic targets. We performed WES on formalin-fixed paraffin-embedded (FFPE) biopsy materials collected from 19 patients affected by conventional high-grade OS. The clinical and genetic data were analyzed according to response to therapy, presence of metastasis and disease status. By comparing good and poor responders to neoadjuvant therapy, we detected a clear prevalence of mutations in the ARID1A, CREBBP, BRCA2 and RAD50 genes in poor responders that negatively influence the progression-free survival time. Moreover, higher tumor mutational burden values correlated with worse prognosis. The identification of mutations in ARID1A, CREBBP, BRCA2 and RAD50 may support the use of a more specific therapy for tumors harboring these alterations. In particular, BRCA2 and RAD50 are involved in homologous recombination repair, and could thus be used as specific therapy targets of inhibitors of the enzyme Poly ADP Ribose Polymerase (PARP). Finally, tumor mutational burden is found to be a potential prognostic marker for OS.

Ninety Percent or Greater Tumor Necrosis Is Associated With Survival and Social Determinants of Health in Patients With Osteosarcoma in the National Cancer Database

BACKGROUND

The histologic response of osteosarcoma to chemotherapy is commonly cited as a prognostic factor and typically graded as the percent necrosis of the tumor at the time of surgical resection. Few studies, to our knowledge, have examined the relationship of tumor necrosis relative to other factors. Existing studies are limited by prolonged enrollment periods or analysis of patient subsets without the strongest predictor of mortality: metastasis at diagnosis. Additionally, the definitive threshold value for a good histologic response is commonly set at more than 90% tumor necrosis with little evidence; some authors advocate other values.

QUESTION/PURPOSES

(1) Are there alternative cutoff values for a good response to chemotherapy in a large, national cohort of contemporarily treated patients with osteosarcoma? (2) How does the association of histologic response to survival in osteosarcoma compare with other clinicopathologic factors? (3) What patient and clinical factors are associated with the histologic response?

METHODS

We identified 2006 patients with osteosarcoma diagnosed between 2010 and 2015 in the National Cancer Database (NCDB), a registry that includes 70% of all new cancers diagnosed in the United States with 90% follow-up. Patients were excluded for missing documentation of percent tumor necrosis (21% [425 of 2006]) or if definitive resection was not performed (< 1% [1 of 2006]). A total of 1580 patients were included in the analysis, with a mean follow-up duration of 37 ± 22 months. A Kaplan-Meier survival analysis, stratified by the percent tumor necrosis after chemotherapy, was performed for the 5-year period. Other covariates examined were sex, race, socioeconomic score composite, insurance type, Charlson/Deyo score, distance from the hospital, and location (metropolitan, urban, or rural). Clinical and sociodemographic data including patient-identified race from the patient's medical record is input into the NCDB by certified registrars. The NCDB only allows coding of one primary race for each patient; thus, most of our patients were grouped as White or Black race and the remaining were grouped as Other for our analysis. A multiple Cox regression analysis was performed to evaluate the effect of percent necrosis compared with other demographic, clinicopathologic, and treatment effects on survival. Finally, a multiple logistic regression analysis was performed to assess demographic and clinicopathologic characteristics associated with percent necrosis.

RESULTS

Five-year overall survival for patients with histologic gradings of 90% to 94% necrosis (70% [95% confidence interval (CI) 60.6% to 79.7%) and 95% to 100% necrosis (74% [95% CI 68% to 80.3%) was not different between groups (p = 0.47). A comparison of histologic responses below 90% necrosis found no difference in survival between patients with decreasing histologic response (p > 0.05). Necrosis of less than 90% was associated with worse survival (HR 2.00 [95% CI 1.58 to 2.52]; p < 0.001 compared with more than 90% necrosis), and factors most associated with poor survival were metastasis (HR 2.85 [95% CI 2.27 to 3.59]; p < 0.001) and skip metastasis at the time of diagnosis (HR 2.52 [95% CI 1.64 to 3.88]; p < 0.001). On multivariate analysis, adjusting for demographic, clinicopathologic, and treatment factors, social determinants of health were negatively associated with percent necrosis of 90% or more, including uninsured status (OR 0.46 [95% CI 0.23 to 0.92]; p = 0.02 compared with private insurance) and lower socioeconomic status composite (OR for the lowest first and second quartiles were 0.63 [95% CI 0.44 to 0.90]; p = 0.01 and 0.70 [95% CI 0.50 to 0.96]; p = 0.03, respectively). Race other than White or Black (OR 0.61 [95% CI 0.40 to 0.94]; p = 0.02 compared with White race) was also negatively associated with percent necrosis of more than 90% after controlling for available covariates.

CONCLUSION

This study suggests that a cutoff of 90% necrosis provides the best prognostic value for patients with osteosarcoma undergoing chemotherapy. Other threshold values did not show different survival benefits. Sociodemographic factors were associated with histologic response less than 90%. These associations must be carefully understood not as cause and effect but likely demonstrating the effects of health disparities and access to care. Although we controlled for multiple variables in our analysis, broad variables such as race may have been associated with histologic response due to unaccounted confounders. Medical providers should be aware of these associations to ensure equitable access and delivery of care because access to care may be responsible for these associations. Future studies should examine potential drivers of this observation, such as a delay in presentation or deviation from standard of care practices.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Prognostic analysis of telangiectatic osteosarcoma of the extremities

Background and objectives

Telangiectatic osteosarcoma (TOS) is a rare but highly malignant subtype of osteosarcoma. Although surgical treatment is the primary treatment modality for osteosarcoma, evidence on the benefits of different surgical methods in patients with TOS is lacking. This study aimed to compare the effects of different surgical and adjuvant treatments on overall survival of TOS, and the association of patient demographics, oncological characteristics, and socioeconomic status on treatment outcomes.

Method

This retrospective study selected the most common TOS cases of the extremities registered in the Surveillance, Epidemiology, and End Results (SEER) database from 1989 to 2019. Univariate and multivariate Cox regression models were used to analyze all prognostic factors, and Kaplan-Meier analyses were performed for disease-specific treatment factors of survival.

Result

A total of 127 patients were included in the analysis. The average age at initial diagnosis was 20.09 years. In univariate analyses, the absence of metastasis at initial diagnosis, limb-salvage surgery, adjuvant chemotherapy, and no regional lymph node dissection were associated with a lower risk of death. Multivariate analysis further showed that the presence or absence of distant metastasis and regional lymph node dissection, implementation of adjuvant chemotherapy, and choice of surgical method were independent predictors of prognosis.

Conclusion

Distant metastasis and regional lymph node dissection are associated with poorer outcomes in TOS, and amputation has no better prognosis than limb salvage surgery. Compared with conventional chemotherapy, neoadjuvant chemotherapy did not significantly improve the prognosis of TOS.

The strategy and clinical relevance of in vitro models of MAP resistance in osteosarcoma: a systematic review

Over the last 40 years osteosarcoma (OS) survival has stagnated with patients commonly resistant to neoadjuvant MAP chemotherapy involving high dose methotrexate, adriamycin (doxorubicin) and platinum (cisplatin). Due to the rarity of OS, the generation of relevant cell models as tools for drug discovery is paramount to tackling this issue. Four literature databases were systematically searched using pre-determined search terms to identify MAP resistant OS cell lines and patients. Drug exposure strategies used to develop cell models of resistance and the impact of these on the differential expression of resistance associated genes, proteins and non-coding RNAs are reported. A comparison to clinical studies in relation to chemotherapy response, relapse and metastasis was then made. The search retrieved 1891 papers of which 52 were relevant. Commonly, cell lines were derived from Caucasian patients with epithelial or fibroblastic subtypes. The strategy for model development varied with most opting for continuous over pulsed chemotherapy exposure. A diverse resistance level was observed between models (2.2-338 fold) with 63% of models exceeding clinically reported resistance levels which may affect the expression of chemoresistance factors. In vitro p-glycoprotein overexpression is a key resistance mechanism; however, from the available literature to date this does not translate to innate resistance in patients. The selection of models with a lower fold resistance may better reflect the clinical situation. A comparison of standardised strategies in models and variants should be performed to determine their impact on resistance markers. Clinical studies are required to determine the impact of resistance markers identified in vitro in poor responders to MAP treatment, specifically with respect to innate and acquired resistance. A shift from seeking disputed and undruggable mechanisms to clinically relevant resistance mechanisms may identify key resistance markers that can be targeted for patient benefit after a 40-year wait.

Diaphyseal Tibial Osteosarcoma With Myiasis

Osteosarcoma is a tumour that can originate in any bone and is the most frequent malignant tumour of the skeleton. It typically develops close to the metaphyseal growth plates in the limbs' long bones. The three most prevalent places are the femur, tibia, and humerus. Additional locations include the pelvis, skull, and jaw. Diaphyseal osteosarcoma involves a smaller population and is highly uncommon. Conventional kinds of osteosarcoma, such as osteoblastic, chondroblastic, and fibroblastic types, as well as telangiectatic, multifocal, parosteal, and periosteal types, are some of the variations of the disease. The primary bone tumour (cancerous) is generated by the formation of immature bone and primarily affects adolescents. We present a case of a 45-year-old menopausal female with left tibial osteosarcoma of the proximal 1/3 diaphysis infected with maggots and complaints of left knee pain and tingling.

Current and future targeted alpha particle therapies for osteosarcoma: Radium-223, actinium-225, and thorium-227

Osteosarcoma is a high-grade sarcoma characterized by osteoid formation, nearly universal expression of IGF1R and with a subset expressing HER-2. These qualities provide opportunities for the use of the alpha particle-emitting isotopes to provide targeted radiation therapy via alpha particles precisely to bone-forming tumors in addition to IFG1R or Her-2 expressing metastases. This review will detail experience using the alpha emitter radium-223 (²²³Ra, tradename Xofigo), that targets bone formation, in osteosarcoma, specifically related to patient selection, use of gemcitabine for radio-sensitization, and using denosumab to increasing the osteoblastic phenotype of these cancers. A case of an inoperable left upper lobe vertebral-paraspinal-mediastinal osteoblastic lesion treated successfully with ²²³Ra combined with gemcitabine is described. Because not all areas of osteosarcoma lesions are osteoblastic, but nearly all osteosarcoma cells overexpress IGF1R, and some subsets expressing Her-2, the anti-IGF1R antibody FPI-1434 linked to actinium-225 (²²⁵Ac) or the Her-2 antibody linked to thorium-227 (²²⁷Th) may become other means to provide targeted alpha particle therapy against osteosarcoma (NCT03746431 and NCT04147819).

Limb salvage surgery has a higher complication rate than amputation but is still beneficial for patients younger than 10 years old with osteosarcoma of an extremity

BACKGROUND/PURPOSE

Limb preserving surgery for the treatment of patients with osteosarcoma younger than 10 years old is challenging and some authors have advocated amputation to reduce the risk of complications. The aim of this study was to compare the clinical outcomes and surgical complications of patients with osteosarcoma of the extremity aged <10 years old who were treated with limb salvage and amputation.

PATIENTS AND METHODS

Retrospective review of patients aged <10 years old who were treated for primary osteosarcoma of bone between 2000 and 2018.

RESULTS

We analyzed 82 consecutive patients (32 males, 50 females; median age 8, range 3-9 yrs). Limb-salvage surgery (LSS; n = 65, 79%) and amputation (n = 17, 21%) were performed. Fourteen patients had metastasis at surgery. In patients without metastasis at surgery, the metastasis-free and overall survival rates at 5 years following LSS vs. amputation were 75% vs. 58% (p = 0.162) and 71% vs. 55% (p = 0.516), respectively. The 2-year and 5-year OS rates of the LSS and amputation groups of patients with metastasis at surgery were 88% versus 83% and 50% versus 0%, respectively (p = 0.180). The overall complication rates were 46% post-LSS with 31% requiring re-operation versus 12% post-amputation, with 6% requiring re-operation (p = 0.010).

CONCLUSION

The prognosis of patients with localized osteosarcoma aged <10 years undergoing LSS is similar to those treated with amputation, but LSS is associated with a higher risk of complications and subsequent re-operation.

LEVEL OF EVIDENCE

Level III.

The Management of an Open Biopsy Tract Site Infection and Ulceration in the Setting of Osteosarcoma

Biopsy site infection in the setting of osteosarcoma is a potentially devastating complication. We present the case of a 16-year-old adolescent girl with a distal femur osteosarcoma who developed an open biopsy site ulceration and infection after initiation of neoadjuvant chemotherapy. This was treated with careful local excision of the ulcerated biopsy site and systemic antibiotic therapy throughout the duration of her chemotherapy course. She subsequently underwent wide resection of the tumor en bloc with a generous ellipse around the biopsy scar and reconstruction with cemented knee megaprosthesis. No recurrence of either infection or malignancy was observed. This case represents the successful treatment of a biopsy site ulceration and infection in a patient with osteosarcoma and may merit adoption in future instances of this complication.

Prognostic Significance of Clinical and Post-Neoadjuvant Chemotherapy Associated Histomorphological Parameters in Osteosarcoma: A Retrospective Study from a Tertiary Care Center

Introduction Osteosarcoma is the most prevalent bone cancer in adolescents. Neoadjuvant chemotherapy (NACT) followed by resection is the current modality of treatment for osteosarcoma. Histological evaluation of extent of tumor necrosis on resection is a well-established prognostic indicator in osteosarcoma correlating with survival in most cases.

Objectives The main objective of this study was to establish prognostic significance of various clinical and histological parameters post-NACT in osteosarcoma and to compare the integrated prognostic index proposed by Chui et al, with grading of response to NACT by Huvos and Rosen for osteosarcoma.

Materials and Methods This is a retrospective study done over a period of four years and includes 47 cases of osteosarcoma treated with NACT. All slides were reviewed and association of various clinical and histological parameters with overall survival was assessed with chi-squared test and Cox-regression analysis.

Results Statistical analysis revealed the prognostic significance of age at presentation, anatomic site, primary tumor size, metastatic status, and clinical stage. Histological parameters such as mitosis ≥10/10hpfs, ≥10% residual tumor were significantly associated with poor survival. Tumor necrosis ≥ 90% (excluding areas of hemorrhage, fibrosis and acellular osteoid) was significantly associated with increased survival. An integrated prognostic index formed by combining above parameters gives a better estimate of overall survival compared with residual disease or necrosis alone.

Conclusion Integrated prognostic index improves prognostication in patients treated for osteosarcoma.

Extent of tumor fibrosis/hyalinization and infarction following neoadjuvant radiation therapy is associated with improved survival in patients with soft-tissue sarcoma

Introduction

Current standard of care for most intermediate and high‐grade soft‐tissue sarcomas (STS) includes limb‐preserving surgical resection with either neoadjuvant radiation therapy (NRT) or adjuvant radiation therapy. To date, there have been a few studies that attempt to correlate histopathologic response to NRT with oncologic outcomes in patients with STS.

Methods

Using our institutional database, we identified 58 patients who received NRT followed by surgical resection for primary intermediate or high‐grade STS and 34 patients who received surgical resection without NRT but did receive adjuvant radiation therapy or did not receive any radiation therapy. We analyzed four histologic parameters of response to therapy: residual viable tumor, fibrosis/hyalinization, necrosis, and infarction (each ratiometrically determined). Data were stratified into two binary groups. Unadjusted, 5‐ and 10‐year overall survival, and relapsed‐free survival (RFS) were calculated using the Kaplan–Meier method.

Results

Analysis of pathologic characteristics showed that patients treated with NRT demonstrate significantly higher tumor infarction, higher tumor fibrosis/hyalinization, and a lower percent viable tumor compared with patients not treated with NRT (p < 0.0001). Based on Kaplan–Meier curve analysis and multivariate cox proportional hazard model for OS and RFS, patients treated with NRT and showing >12.5% tumor fibrosis/hyalinization have significantly higher overall survival and recurrence‐free survival at 5 and 10 years.

Discussion and Conclusion

We have identified three histopathologic characteristics—fibrosis, hyalinization, and infarction—that may serve as predictive biomarkers of response to NRT for STS patients. Future prospective studies will be needed to confirm this association.

What is the standard indication of adjuvant or neoadjuvant chemotherapy in localized soft-tissue sarcoma?

PURPOSE OF REVIEW

The aim is to bring latest evidence of the role of perioperative chemotherapy in localized soft-tissue sarcomas (STS) of limbs and to review the risk classification systems of retroperitoneal and extremity STS.

RECENT FINDINGS

High-risk subset of localized STS of limbs and trunk-wall, defined with classic prognostic factors, consistently obtained 5-year overall survival ranging from 69 to 76% in randomized patients treated with full-dose of anthracycline and ifosfamide. Validated nomograms accurately predict, on individual basis, the risk of death and recurrence in localized STS of retroperitoneum and limbs, enabling a better selection of high-risk patients (usually those with death risk of ≥40%) that potentially could benefit with perioperative systemic treatment. Nomograms have virtually converted a negative large perioperative trial into a positive, favouring chemotherapy arm in the high-risk selection.

SUMMARY

Perioperative three cycles of full-dose of anthracycline and ifosfamide should be proposed on an individual basis, in reference sarcoma centres, to high-risk localized STS of limbs or trunk-wall in certain histologies.

Correlation between Prognostic Factors and the Histopathological Response to Neoadjuvant Chemotherapy in Osteosarcoma: A Retrospective Study

Background

Multimodality treatment, incorporating neoadjuvant chemotherapy and adjuvant chemotherapy, is the standard management plan for osteosarcoma that increases the overall survival (OS) rate. However, data regarding prognostic factors affecting the histopathological response following neoadjuvant chemotherapy is limited. Patients and Methods. We retrospectively reviewed patients diagnosed with osteosarcoma in our center between 2008 and 2018. We classified patient characteristics according to gender, age, tumor size, site and stage at diagnosis, site of metastasis, type of surgery, necrosis rate based on the Huvos grading system, and the number of neoadjuvant chemotherapy cycles. We divided response to neoadjuvant chemotherapy into poor responder for patients with Huvos grades 1 and 2 and good responder for patients with Huvos grades 3 and 4. We also documented patients' survival and follow-up information.

Results

We reviewed 64 patients within 5–65 years of age, dominated by men (62.5%). The distal femur (53.1%) was the most common site of osteosarcoma. Fifteen (23.4%) patients had a good response while 49 (76.6%) patients were poor responders to neoadjuvant chemotherapy based on the Huvos grading system. Based on multivariate analysis, gender (p = 0.012), age (p = 0.029), symptom duration (p = 0.004), and tumor enlargement after neoadjuvant chemotherapy (p < 0.001) were significantly associated with histopathological response. A scoring system was proposed integrating these significant variables (age > 20 years = 1 point, female gender = 1 point, symptom duration > 12 weeks = 1 point, and increased tumor size after neoadjuvant chemotherapy = 2 points). This scoring system divides patients into two groups with a total score of more than two predicting a poor responder to neoadjuvant chemotherapy.

Conclusions

Age, gender, symptoms duration, and tumor size after neoadjuvant chemotherapy are the prognostic features that affect the histopathological response to neoadjuvant chemotherapy in patients with osteosarcoma.

The Plasma Concentration of D-Dimer is Associated with Neoadjuvant-Chemotherapy Efficacy and the Prognosis in Osteosarcoma

PURPOSE

This retrospective study explored the clinical value of the plasma D-dimer level in osteosarcoma.

MATERIALS AND METHODS

We measured the plasma D-dimer level before neoadjuvant chemotherapy (D0) and the plasma D-dimer level after four courses of neoadjuvant chemotherapy (D1) in 103 patients with stage-IIB high-grade osteosarcoma of the limb. The change in the D-dimer level (ΔD) was defined as D1 minus D0. The chi-square test was used to compare categorical variables. Analyses of receiver operating characteristic (ROC) curves were undertaken to determine the optimal cutoff points for D0, D1, and ΔD. The area under the ROC (AUC) of D0, D1, and ΔD was calculated to evaluate their discriminatory abilities in monitoring the response to neoadjuvant chemotherapy (tumor necrosis). Survival curves were generated according to Kaplan-Meier analyses and compared using the Log rank test. Univariate analyses and multivariate analyses were carried out to determine independent prognostic factors.

RESULTS

Kaplan-Meier curves showed that a high D-dimer level at D0 and tumor diameter ≥8 cm were associated significantly with worse overall survival (OS) (P<0.05). Multivariate Cox regression analyses revealed a high D-dimer level at D0 (hazard ratio, 3.92; 95% confidence interval, 1.756-5.804; P=0.000) was an independent unfavorable prognostic factor. The chi-square test showed ΔD to be associated significantly with tumor necrosis. Analyses of ROC curves showed the D-dimer level at D0 and ΔD had better ability compared to that at D1 to discriminate the response to neoadjuvant chemotherapy.

CONCLUSION

The D-dimer level was correlated with the prognosis and response to chemotherapy in patients with stage-IIB high-grade osteosarcoma of the limb. The D-dimer level may serve as a risk factor of the response to chemotherapy and prognosis of localized osteosarcoma.

Additive manufacturing of hydrogel-based materials for next-generation implantable medical devices

Implantable microdevices often have static components rather than moving parts, and exhibit limited biocompatibility. This paper demonstrates a fast manufacturing method which can produce features in biocompatible materials down to tens of microns in scale, with intricate and composite patterns in each layer. By exploiting unique mechanical properties of hydrogels, we developed a "locking mechanism" for precise actuation and movement of freely moving parts, which can provide functions such as valves, manifolds, rotors, pumps, and delivery of payloads. Hydrogel components could be tuned within a wide range of mechanical and diffusive properties, and can be controlled after implantation without a sustained power supply. In a mouse model of osteosarcoma, triggering of release of doxorubicin from the device over ten days showed high treatment efficacy and low toxicity, at one-tenth of a standard systemic chemotherapy dose. Overall, this platform, called "iMEMS", enables development of biocompatible implantable microdevices with a wide range of intricate moving components that can be wirelessly controlled on demand, in a manner that solves issues of device powering and biocompatibility.

Radiological Assessment and Outcome of Local Disease Progression after Neoadjuvant Chemotherapy in Children and Adolescents with Localized Osteosarcoma

Objective: We examined the interobserver reliability of local progressive disease (L-PD) determination using two major radiological response evaluation criteria systems (Response evaluation Criteria in Solid Tumors (RECIST) and the European and American Osteosarcoma Study (EURAMOS)) in patients diagnosed with localized osteosarcoma (OS). Additionally, we describe the outcomes of patients determined to experience L-PD. Materials and Methods: Forty-seven patients diagnosed with localized OS between 2000 and 2012 at our institution were identified. Paired magnetic resonance imaging of the primary tumor from diagnosis and post-neoadjuvant chemotherapy were blindly assessed by two experienced radiologists and determined L-PD as per RECIST and EURAMOS radiological criteria. Interobserver reliability was measured using the kappa statistic (κ). The Kaplan Meier method and log-rank test was used to assess differences between groups. Results: Of 47 patients (median age at diagnosis 12.9 years), 16 (34%) had L-PD (by RECIST or EURAMOS radiological definition). There was less agreement between the radiologists using EURAMOS radiological criteria for L-PD (80.9%, κ = 0.48) than with RECIST criteria (97.9%, κ = 0.87). Patients with radiologically defined L-PD had a 5-year progression-free survival (PFS) of 55.6%, compared to a 5 year-PFS of 82.7% in the group of patients without L-PD (n = 31) (Log rank p = 0.0185). Conclusions: The interobserver reliability of L-PD determination is higher using RECIST than EURAMOS. RECIST can be considered for response assessment in OS clinical trials. The presence of L-PD was associated with worse outcomes.

PD-1 and PD-L1 Expression in Osteosarcoma: Which Specimen to Evaluate?

There is a growing interest in immunotherapy in childhood cancers. Osteosarcoma is a compelling potential target as there are few targeted options available for this aggressive cancer. We provide a description of the landscape of programmed cell death-1 (PD-1), programmed cell death-ligand 1 (PD-L1) and relevant immune markers in serial samples from 15 osteosarcoma patients. PD-1 and PD-L1 expression was present in biopsy samples (47% and 53%, respectively), absent in resections, and present in metastases (40% and 47%). Both decalcified and nondecalcified specimens demonstrated expression of PD-1 and PD-L1. The results suggest that biopsy or metastatic specimens maybe most valuable in assessing expression of PD-1 and PD-L1.

Treatment effect prediction for sarcoma patients treated with preoperative radiotherapy using radiomics features from longitudinal diffusion-weighted MRIs

The objective of this study was to explore radiomics features from longitudinal diffusion-weighted MRIs (DWIs) for pathologic treatment effect prediction in patients with localized soft tissue sarcoma (STS) undergoing hypofractionated preoperative radiotherapy (RT). Thirty patients with localized STS treated with preoperative hypofractionated RT were recruited to this longitudinal imaging study. DWIs were acquired at three time points using a 0.35 T MRI-guided radiotherapy system. Treatment effect score (TES) was obtained from the post-surgery pathology as a surrogate of treatment outcome. Patients were divided into two groups based on TES. Response prediction was first performed using a support vector machine (SVM) with only mean apparent diffusion coefficient (ADC) or delta ADC to serve as the benchmark. Radiomics features were then extracted from tumor ADC maps at each of the three time points. Logistic regression and SVM were constructed to predict the TES group using features selected by univariate analysis and sequential forward selection. Classification performance using SVM with features from different time points and with or without delta radiomics were evaluated. Prediction performance using only mean ADC or delta ADC was poor (area under the curve (AUC) < 0.7). For the radiomics study using features from all time points and corresponding delta radiomics, SVM significantly outperformed logistic regression (AUC of 0.91 ± 0.05 v.s. 0.85 ± 0.06). Prediction AUC values using single or multiple time points without delta radiomics were all below 0.74. Including delta radiomics of mid- or post-treatment relative to the baseline drastically boosted the prediction. In this work, an SVM model was built to predict the TES using radiomics features from longitudinal DWI. Based on this study, we found that use of mean ADC, delta ADC, or radiomics features alone was not sufficient for response prediction, and including delta radiomics features of mid- or post-treatment relative to the baseline can optimize the prediction of TES, a pathologic and clinical endpoint.

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

PURPOSE

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSION

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

Impact of chemotherapy-induced necrosis on event-free and overall survival after preoperative MAP chemotherapy in patients with primary high-grade localized osteosarcoma

AIMS

To assess the correlation between the histological response to preoperative chemotherapy and event-free survival (EFS) or overall survival (OS) in patients with high-grade localized osteosarcoma.

METHODS

Out of 625 patients aged ≤ 40 years treated for primary high-grade osteosarcoma between 1997 and 2016, 232 patients without clinically detectable metastases at the time of diagnosis and treated with preoperative high-dose methotrexate, adriamycin and cisplatin (MAP) chemotherapy and surgery were included. Associations of chemotherapy-induced necrosis in the resected specimen and EFS or OS were assessed using Cox model and the Pearson's correlation coefficients (r). Time-dependent receiver operating characteristic analysis was applied to determine the optimal cut-off value of chemotherapy-induced necrosis for EFS and OS.

RESULTS

OS was 74% (95% confidence interval (CI) 67 to 79) at five years. Median chemotherapy-induced necrosis was 85% (interquartile range (IQR) 50% to 97%). In multivariate Cox model, chemotherapy-induced necrosis was significantly associated with EFS and OS (hazard ratio (HR) = 0.99 (95% CI 0.98 to 0.99); p < 0.001 and HR = 0.98 (95% CI 0.97 to 0.99); p < 0.001, respectively). Positive correlation was observed between chemotherapy-induced necrosis and five-year EFS and five-year OS (r = 0.91; p < 0.001, and r = 0.85; p < 0.001, respectively). The optimal cut-off value of chemotherapy-induced necrosis for five-year EFS and five-year OS was 85% and 72%, respectively.

CONCLUSION

Chemotherapy-induced necrosis in the resected specimen showed positive correlation with EFS and OS in patients with high-grade localized osteosarcoma after MAP chemotherapy. In our analysis, optimal cut-off values of MAP chemotherapy-induced necrosis in EFS and OS were lower than the commonly used 90%, suggesting the need for re-evaluation of the optimal cut-off value through larger, international collaborative research. Cite this article: Bone Joint J 2020;102-B(6):795-803.

Tumor-infiltrating lymphocytes as a feasible adjuvant immunotherapy for osteosarcoma with a poor response to neoadjuvant chemotherapy

Aim: To investigate the efficacy of adjuvant chemotherapy plus tumor-infiltrating lymphocytes (TILs) therapy in osteosarcoma patients with a poor response to neoadjuvant chemotherapy. Materials & methods: 40 patients received adjuvant chemotherapy (Group 1) and 40 patients received adjuvant chemotherapy plus TILs therapy (Group 2). Disease-free survival (DFS) and overall survival (OS) were analyzed by Kaplan–Meier analysis. Results: The median DFS (mDFS; 65.3 months) and median OS (mOS; 95.8 months) in Group 2 were significantly prolonged compared with those in Group 1 (55.5 months for mDFS and 80.4 months for mOS). Univariate and multivariate analyses indicated that a greater number of TILs transfused was an independent prognostic factor for both mDFS and mOS. Conclusion: Adjuvant chemotherapy plus TILs therapy may prolong survival of patients with a poor response to neoadjuvant chemotherapy.

Is Microscopic Vascular Invasion in Tumor Specimens Associated with Worse Prognosis in Patients with High-grade Localized Osteosarcoma?

BACKGROUND

Other than metastases at diagnosis and histological response to preoperative chemotherapy, there are few reliable predictors of survival in patients with osteosarcoma. Microscopic vascular invasion (MVI) has been identified in the resection specimens of patients with osteosarcoma. However, it is unknown whether the MVI in resected specimens is associated with worse overall survival and higher cumulative incidence of local recurrence or metastasis in a large cohort of patients younger than 40 years with high-grade localized osteosarcoma.

QUESTIONS/PURPOSES

(1) Is MVI associated with worse overall survival and higher cumulative incidence of events (local recurrence or metastasis) in patients younger than 40 years with high-grade localized osteosarcoma? (2) What clinical characteristics are associated with MVI in patients with high-grade localized osteosarcoma?

METHODS

A total of 625 patients younger than 40 years with primary high-grade osteosarcoma between 1997 and 2016 were identified in our oncology database. We included patients younger than 40 years with primary high-grade osteosarcoma who underwent definitive surgery and preoperative and postoperative chemotherapy. The minimum follow-up period was 2 years after treatment. Patients with the following were excluded: metastasis at initial presentation (21%, n = 133), progression with preoperative chemotherapy precluding definitive surgery (6%, n = 38), surgery at another unit (2%, n = 13), lost to follow-up before 2 years but not known to have died (3%, n = 18), and death related to complications of preoperative chemotherapy (1%, n = 4). A retrospective pathologic and record review was conducted in the remaining 419 patients. The median follow-up period was 5 years (interquartile range [IQR] 3 to 9 years). The overall survival of the entire group (n = 419) was 67% [95% CI 63 to 72] at 5 years. Of the 419 patients, 10% (41) had MVI in their resection specimens. The Kaplan-Meier method was used to estimate overall survival. The cumulative incidence of events captured the first event of either metastasis or local recurrence. This analysis was completed with a competing risk framework: deaths without evidence of local recurrence or metastasis were regarded as a competing event. Clinical and histological variables (sex, age, tumor site, tumor largest dimension, surgical margin, chemotherapy-induced necrosis, type of surgery, histologic type of tumor, type of chemotherapy regimen, pathologic fracture, and MVI) were evaluated using the log-rank test or Gray test in the univariate analyses and Cox proportional hazard model or Fine and Gray model in the multivariate analyses.

RESULTS

After adjusting for other factors, multivariate analyses showed that the presence of MVI in resection specimens was associated with worse overall survival and higher cumulative incidence of event (hazard ratio 1.88 [95% CI 1.22 to 2.89]; p = 0.004 and HR 2.33 [95% CI 1.56 to 3.49]; p < 0.001, respectively). A subgroup analysis demonstrated that the relationship between MVI and survival applied only to patients with a poor response to chemotherapy (less than 90% necrosis; overall survival at 5 years, MVI [+] = 24% [95% CI 11 to 39] versus MVI [-] = 60% [95% CI 52 to 66]; p < 0.001 and cumulative incidence of events at 5 years, MVI [+] = 86% [95% CI 68 to 94] versus MVI [-] = 54% [95% CI 46 to 61]; p < 0.001). The MVI (+) group had a higher proportion of patients with a poor response to chemotherapy (85% [35 of 41] versus 53% [201 of 378]; p < 0.001), involved margins (15% [6 of 41] versus 5% [18 of 378]; p = 0.021), and limb-ablative surgery (37% [15 of 41] versus 21% [79 of 378]; p = 0.022) than the MVI (-) group did.

CONCLUSIONS

MVI is associated with lower overall survival and higher cumulative incidence of local recurrence or metastasis, especially in patients with a poor histologic response to preoperative chemotherapy. Future studies in patients treated for osteosarcoma should consider this observation when planning new trials.

LEVEL OF EVIDENCE

Level III, therapeutic study.

99mTc-MIBI Scintigraphy for the Preoperative Assessment of Histological Response to Neoadjuvant Chemotherapy in Patients With Osteosarcoma: A Systematic Review and a Bivariate Meta-Analysis

Purpose: There have been many attempts to preoperatively evaluate the chemotherapy response of osteosarcoma patients using ^99mTc-MIBI scintigraphy. However, the evaluations were lacking in consistency. We performed this systematic review and meta-analysis to systematically evaluate the ability of ^99mTc-MIBI scintigraphy in preoperatively assessing the response of osteosarcoma patients to neoadjuvant chemotherapy. Methods: For this systematic review and meta-analysis, PubMed, Web of Science, OVID, the Cochrane Library, and CNKI were searched. Eligible studies were included based on the defined criteria. The index test was ^99mTc-MIBI scintigraphy, the reference standard was tumor necrosis rate. Quality Assessment of Diagnostic Accuracy Studies-2 was adopted for quality assessment of included studies. The statistical pooling analysis, meta-regression analysis, subgroup analysis, sensitivity analysis, and publication bias of our research were performed using STATA 15. Results: Eight articles with 189 osteosarcoma patients were included in this systematic review and meta-analysis. Our results demonstrated that the threshold effect of our meta-analysis was significant. The uptake change ratio of ^99mTc-MIBI scintigraphy had a pooled sensitivity, specificity, positive and negative likelihood ratio, diagnostic odds ratio, and the area under curve of 0.98 (0.58-1.00), 0.68 (0.47-0.84), 3.1 (1.7-5.5), 0.03 (0.00-0.90), 103 (4-3,003), and 0.91 (0.88-0.93) in preoperative assessment of response of osteosarcoma patients to neoadjuvant chemotherapy. Meta-regression analysis and subgroup analysis indicated the factors of method and cut off value may introduce the heterogeneity. The pooled sensitivity, specificity, positive and negative likelihood ratio, diagnostic odds ratio, and the area under curve of washout rate of ^99mTc-MIBI were 0.87 (0.69-0.95), 0.91 (0.75-0.97), 9.3 (3.2-27.0), 0.15 (0.06-0.37), 64 (14-301), and 0.89 (0.86-0.92), respectively. Sensitivity analysis and publication bias demonstrated our meta-analysis was reliable. Conclusion: Both the ΔUR and WR derived from ^99mTc-MIBI scintigraphy were valuable in preoperatively assessing the response of osteosarcoma patients to neoadjuvant chemotherapy, and ΔUR may possess a more outstanding diagnostic accuracy than WR.

Surrogate endpoints for overall survival in randomised controlled trials of localised osteosarcoma: A meta-analytic evaluation

Event-free survival (EFS) is considered the most reliable surrogate endpoint for overall survival (OS) in randomised controlled trials (RCTs) of adjuvant therapies for malignant tumours. However, the surrogacy of intermediate endpoints such as EFS for OS in trials of patients with osteosarcoma has not been investigated to date. In this study, we investigated the correlation between OS and intermediate endpoints in RCTs of localised osteosarcoma. A systematic search identified 20 relevant RCTs. The correlations between the surrogate endpoints and OS were evaluated using weighted linear regression analyses and by calculating the Spearman rank correlation coefficients (ρ). The strength of the correlation was determined by calculating the coefficient of determination (R2). A total of 5,620 patients were randomly assigned to 45 treatment arms in the eligible 20 RCTs. The correlation between the hazard ratios for EFS and OS was moderate (R2 = 0.456, ρ = 0.440); this correlation tended to be weaker for patients with localised osteosarcoma excluding the patients with metastases. Overall, the trial-level correlation between the surrogate endpoints and OS was not robust in RCTs of osteosarcoma published to date. Hence, the suitability of the intermediate endpoints as surrogates for OS could not be confirmed.

Reprograming the tumor immunologic microenvironment using neoadjuvant chemotherapy in osteosarcoma

Tumor-infiltrating immune cells play a crucial role in tumor progression and response to treatment. However, the limited studies on infiltrating immune cells have shown inconsistent and even controversial results for osteosarcoma (OS). In addition, the dynamic changes of infiltrating immune cells after neoadjuvant chemotherapy are largely unknown. We downloaded the RNA expression matrix and clinical information of 80 OS patients from the TARGET database. CIBERSORT was used to evaluate the proportion of 22 immune cell types in patients based on gene expression data. M2 macrophages were found to be the most abundant immune cell type and were associated with improved survival in OS. Another cohort of pretreated OS samples was evaluated by immunohistochemistry to validate the results from CIBERSORT analysis. Matched biopsy and surgical samples from 27 patients were collected to investigate the dynamic change of immune cells and factors before and after neoadjuvant chemotherapy. Neoadjuvant chemotherapy was associated with increased densities of CD3+ T cells, CD8+ T cells, Ki67 + CD8+ T cells and PD-L1+ immune cells. Moreover, HLA-DR-CD33+ myeloid-derived suppressive cells (MDSC) were decreased after treatment. We determined that the application of chemotherapy may activate the local immune status and convert OS into an immune "hot" tumor. These findings provide rationale for investigating the schedule of immunotherapy treatment in OS patients in future clinical trials.

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.

Polyethylenimine-dextran-coated magnetic nanoparticles loaded with miR-302b suppress osteosarcoma in vitro and in vivo

Aim: We attempted to synthesize a magnetic gene carrier with poly(ethylenimine), dextran and iron oxide nanoparticles (PDIs) for miR-302b transfection in vitro and in vivo. Materials & methods: The nanoparticles were characterized for hydrodynamic properties, ζ potential and DNA-binding ability, evaluated by transmission electron microscopy. Cellular internalization, magnetofection efficiency and anti-osteosarcoma effects were investigated in osteosarcoma (OS) cells and OS-bearing nude mice. Results: PDIs were successfully prepared and showed mild cytotoxicity. A magnetic field efficiently enabled transport of PDI/pmiR302b to OS cells in OS-bearing nude mice, exerting the anti-osteosarcoma effect of miR-302b at the tumor site. The inhibitory effect of miR-302b on osteosarcoma-bearing nude mice may be attributed to regulation of the Hippo pathway through YOD1. Conclusion: Low-cytotoxic PDIs have potential applications as a magnetic transport carrier for future osteosarcoma treatment.

Outcomes in Treatment-Naïve Patients With Metastatic Extremity Osteosarcoma Treated With OGS-12, a Novel Non-High-Dose Methotrexate-Based, Dose-Dense Combination Chemotherapy, in a Tertiary Care Cancer Center

Purpose

Metastatic osteosarcoma is largely treated with high-dose methotrexate (HDMTX)–based therapy, especially in the pediatric population. This mandates complex pharmacokinetic monitoring in a costly inpatient setting to mitigate unpredictable serious toxicities. Hence, a non-HDMTX–based regimen is worth exploring, especially in India and low- and middle-income countries.

Materials and Methods

All consecutive treatment-naïve patients with metastatic osteosarcoma were prospectively treated on the novel OGS-12 protocol consisting of sequential doublets of doxorubicin, cisplatin, and ifosfamide. Four cycles were administered as neoadjuvant therapy followed by planned curative intent surgery and metastasectomy when feasible, followed by four cycles of adjuvant chemotherapy. Baseline characteristics, histologic response, event-free survival (EFS), overall survival (OS), and toxicity data were prospectively collected.

Results

Three hundred seventeen patients were enrolled onto the OGS-12 protocol from 2011 to 2014, of whom 80 (25%) had metastatic disease; median age was 17 years. The majority of patients were nutritionally challenged with high-risk features. At presentation, 83% of patients (66 patients) had lung metastases. After neoadjuvant chemotherapy, 57% of patients were histologically good responders. Four-year EFS and OS rates were 24% and 27%, respectively, in the intent-to-treat population and 27% and 29%, respectively, in the per-protocol analysis. Significant grade 3 or 4 toxicities were febrile neutropenia (51%), thrombocytopenia (36%), and anemia (54%). Histologic response was an independent predictor for EFS and OS in patients who underwent surgery. Surgical intervention was found to be significant for survival in univariable analysis.

Conclusion

The novel, low-cost, non-HDMTX–based, dose-dense OGS-12 regimen has shown comparable outcomes to international standards in metastatic osteosarcomas and is worthy of wider clinical application. An aggressive multimodality approach may result in long-term survival in a select group of patients and, hence, is worth considering.

Differential Clinical Significance of Neurotrophin-3 Expression according to MYCN Amplification and TrkC Expression in Neuroblastoma

BACKGROUND

Neurotrophin-3 (NT-3), a member of the NT family, has only been considered an ancillary compound that provides anti-apoptotic benefits by inactivating tropomyosin receptor kinase C (TrkC)-induced apoptotic signals. However, little is known about the clinical relevance of NT-3 expression itself in neuroblastoma. The purpose of this study was to assess NT-3 expression in patients with neuroblastoma and its relevance to clinicopathologic findings and treatment outcomes.

METHODS

In this study, expression of NT-3 and TrkC was analyzed using immunohistochemistry in 240 patients with newly diagnosed neuroblastoma.

RESULTS

The results of the study revealed that NT-3 expression was associated with older age at diagnosis, localized tumors, and more differentiated tumors but was not associated with early treatment response (degree of residual tumor volume after three cycles of chemotherapy) and progression-free survival (PFS). However, when analysis was confined to patients with MYCN amplified tumors, NT-3 expression was associated with better early treatment response with borderline significance (P = 0.092) and higher PFS (86.9% vs. 58.2%; P = 0.044). In multivariate analysis in patients with MYCN amplified tumors, NT-3 was independent prognostic factor (hazard ratio, 0.246; 95% confidence interval, 0.061-0.997; P = 0.050). In another subgroup analysis, the early treatment response was better if NT-3 was expressed in patients without TrkC expression (P = 0.053) while it was poorer in patients with TrkC expression (P = 0.023).

CONCLUSION

This study suggests that NT-3 expression in neuroblastoma has its own clinical significance independent of TrkC expression, and its prognostic significance differs depending on the status of MYCN amplification and/or TrkC expression.

Pediatric Osteosarcoma of Extremities: A 15-year Experience From a Tertiary Care Cancer Center in Upper Egypt

AIM

To assess the outcome and determine predictors of survival in pediatric patients with osteosarcoma of the extremities treated with a unified chemotherapy protocol at a single institution over a 15-year period.

MATERIALS AND METHODS

We performed a retrospective analysis of medical records of 48 pediatric patients with histologically verified osteosarcoma of the extremities diagnosed at South Egypt Cancer Institute and received treatment between January 2001 and December 2015.

RESULTS

With a median follow-up of 61 months for the entire cohort, estimates of overall survival (OS) for 3- and 5-year were 50.9% and 42.1%, respectively. While the estimates of OS for 3- and 5-year in the nonmetastatic group were 79% and 65.2%, respectively. In the multivariable analysis, both metastatic disease at diagnosis and poor response to chemotherapy retained their statistical significance as independent predictors for event-free survival. Whereas for OS, a metastatic disease at diagnosis remained as the lone predictor of a dismal outcome, while a poor response to chemotherapy became marginally associated with an inferior outcome.

CONCLUSIONS

In Upper Egypt, whereas slightly less than two thirds of children with localized osteosarcoma of extremities survives their disease, metastasis at presentation remains the key predictor of dismal survival outcomes.

Prediction and evaluation of neoadjuvant chemotherapy using the dual mechanisms of 99mTc-MIBI scintigraphy in patients with osteosarcoma

Purpose

To investigate the feasibility of applying the dual imaging mechanisms of ^99mTc-MIBI scintigraphy in predicting and evaluating the response to neoadjuvant chemotherapy in patients with osteosarcoma.

Materials and methods

Thirty patients with osteosarcoma who underwent both pre-and post-chemotherapy ^99mTc-MIBI scintigraphy were enrolled in the study. In each patient, the tumor to background ratio (T/B), tumor washout rate (WR) of MIBI and the alteration rate (AR) of tumor uptake after chemotherapy was calculated, respectively, on MIBI scintigraphy before or after chemotherapy. Based on the tumor necrosis rate histologically confirmed by tumor resection after chemotherapy, the diagnostic performance of MIBI scintigraphy was assessed in predicting tumor response with the WR of pre-chemotherapy imaging, as well as evaluating tumor response with the AR of both pre-and post-chemotherapy imaging.

Results

On pre-chemotherapy MIBI imaging, no statistical difference was found in T/B values between patients with good response and those with poor response, but the WR in patients with good response was significantly lower. Tumor WR was negatively correlated with the tumor necrosis rate (r = −0.510, P = 0.004). When WR ≤ 25% was taken as the threshold for predicting good response, a sensitivity of 100%, a specificity of 91.7% and an accuracy of 95.8% would be yielded. On post-chemotherapy imaging, T/B values both on early and delayed phases were significantly lower in responders and AR of tumor uptake was significantly higher in these responders. When AR ≥ 38% was used as the threshold for a good response, a sensitivity of 91.7%, a specificity of 94.4% and an accuracy of 93.3% would be yielded. The diagnostic coincidence rate between WR for predicting chemotherapy response and AR for evaluating chemotherapy response was 90.0% (kappa = 0.789, P < 0.001).

Conclusion

^99mTc-MIBI imaging is a useful tool for the evaluation of neoadjuvant chemotherapy in patients with osteosarcoma, and its dual mechanisms could be simultaneously used in predicting and evaluating tumor response to chemotherapy.

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.

Prognostic factors to survival of patients with chondroblastic osteosarcoma

This study was aimed to reveal the changes in survival rates and prognostic factors to survival of chondroblastic osteosarcoma (COS).Patients from the Surveillance, Epidemiology, and End Results (SEER) database were retrieved. Kaplan-Meier survival analysis and Cox proportional hazard model were used during analysis.There were significant differences on overall survival between subtypes of osteosarcoma (P < .001*). Overall survival of COS did not change significantly during last forty years (P = .610), and cancer-specific survival increased to a plateau in 1980s and then remained stable (P = .058). Younger onset age, patients of white race, well and moderately differentiated tumors, and surgery independently predicted better overall (Hazard ratio [HR]: 1.034, P < .001*; HR: 0.538, P = .004*; HR: 0.240, P = .020* and HR: 0.350, P < .001*, respectively) and cancer-specific (HR: 1.031, P = .002*; HR: 0.592, P = .036*; HR: 0.098, P = .027* and HR: 0.253, P < .001*, respectively) survival. Metastasis at diagnosis independently predicted worse overall (HR: 3.108, P < .001*) and cancer-specific (HR: 4.26, P < .001*) survival compared to no metastasis.Younger onset age, white race, well and moderately differentiated tumors, no metastasis at diagnosis and surgical resection can independently predict better overall and cancer-specific survival of COS.

Response Evaluation Criteria in Solid Tumors (RECIST) following neoadjuvant chemotherapy in osteosarcoma

BACKGROUND

In osteosarcoma, patient survival has not changed in over 30 years. Multiple phase II trials have been conducted in osteosarcoma using the Response Evaluation Criteria in Solid Tumors (RECIST) as a primary endpoint; however, none of these have revealed new treatment strategies. We investigated RECIST in newly diagnosed patients who received neoadjuvant chemotherapy proven to be beneficial.

METHODS

Patients treated from 1986 to 2011 for newly diagnosed osteosarcoma with paired tumor imaging before and after adequate neoadjuvant chemotherapy were included in this retrospective study. Two radiologists performed independent, blinded (to image timing) RECIST measurements of primary tumor and lung metastases at diagnosis and post-neoadjuvant chemotherapy. Association between RECIST and histological necrosis and outcome were assessed.

RESULTS

Seventy-four patients met inclusion criteria. Five-year overall survival and progression-free survival (PFS) were 77 ± 7% and 61 ± 8%, respectively. No patients had RECIST partial or complete response in the primary tumor. Sixty-four patients (86%) had stable disease, and 10 (14%) had progressive disease (PD). PD in the primary tumor was associated with significantly worse PFS in localized disease patients (P = 0.02). There was no association between RECIST in the primary tumor and necrosis. There were an insufficient number of patients with lung nodules ≥1 cm at diagnosis to evaluate RECIST in pulmonary metastases.

CONCLUSIONS

PD by RECIST predicts poor outcome in localized disease patients. In bone lesions, chemotherapy proven to improve overall survival does not result in radiographic responses as measured by RECIST. Further investigation of RECIST in pulmonary metastatic disease in osteosarcoma is needed.

Long-term outcomes in osteosarcoma patients in the Groote Schuur Hospital patient population: A retrospective review

<strong>Background:</strong> Predictive factors for long-term outcomes in osteosarcoma patients are still controversial. There is no literature available regarding these factors in a patient population in a developing country.<br /><strong>Aim and setting:</strong> To determine the outcome of treatment of osteosarcoma patients treated at Groote Schuur Hospital from 1990 to 2012 in terms of locoregional control (LRC), disease-free survival (DFS) and overall survival (OS) and to determine the value of suggested predictive factors in this population.<br /><strong>Patients and methods:</strong> Retrospective review of all patients diagnosed with and treated for osteosarcoma at Groote Schuur Hospital between 1990 and 2012, considering OS, DFS and LRC. This review assesses the significance of suggested predictive factors from other studies, namely, HIV status, age at diagnosis, site of primary disease, type of chemotherapy used, response to chemotherapy and type of surgery in terms of OS, DFS and LRC.<br /><strong>Results:</strong> Forty-three patients with histologically confirmed osteosarcoma were treated at Groote Schuur Hospital between 1990 and 2012. Median 5 year OS was 57.8%. On univariate analysis, the site of disease was the only statistically significant predictive factor for prognosis.<br /><strong>Conclusion:</strong> On univariate analysis, patients with axial disease have a worse predicted prognosis than those with primary disease in their extremities. The clinical behaviour and long-term outcome after treatment of these patients with osteosarcoma are similar to that seen internationally.

Evaluation of HLA-G, HLA-E, and PD-L1 proteins in oral osteosarcomas

OBJECTIVE

The aim of this study was to investigate the expression of human leukocyte antigens (HLAs) G and E and programmed death-ligand 1 (PD-L1) in oral osteosarcoma (OO) (n = 13). The relationship between the expression of these molecules and histologic grading and metastasis was also evaluated.

STUDY DESIGN

HLA-G, HLA-E, and PD-L1 were identified by immunohistochemistry. Samples of normal bone tissue (n = 6) were used as controls. The sections were evaluated using a semiquantitative scoring system with an immunoreactive score, where a score of 0 was considered absent, ≤2 was low, and >2 was high expression.

RESULTS

We identified high expression of HLA-G, HLA-E, and PD-L1 by malignant osteoblastic cells in 69.2% of OO cases, which was statistically higher than that in controls (P < .05). Overexpression of these proteins was identified in 8 of 11 samples of high-grade and 1 of 2 samples of low-grade OO. Additionally, 66.6% of patients with metastases (n = 4) and 71.4% of patients without metastases (n = 5) had high expression of HLA-G, HLA-E, and PD-L1 in tumor samples (P > .05).

CONCLUSION

OO had high expression of HLA-G, HLA-E, and PD-L1 irrespective of clinicopathologic parameters, including histologic grading and metastasis.

P16 protein expression as a useful predictive biomarker for neoadjuvant chemotherapy response in patients with high-grade osteosarcoma: A systematic meta-analysis under guideline of PRISMA

BACKGROUND

Neoadjuvant chemotherapy for patients with high-grade osteosarcoma has highly improved the clinical survival. However, the prognostic and predictive role of P16 expression after neoadjuvant chemotherapy remains unclear. We first determined whether P16 expression can become a potential prognostic and predictive biomarker in high-grade osteosarcoma.

METHODS

This meta-analysis was conducted based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guideline. Eligible studies were pooled and the overall odds ratios (ORs) and hazard ratios (HRs) with the corresponding 95% confidence intervals (95% CIs) were calculated in this analysis.

RESULTS

Four studies involving a total of 527 patients with high-grade osteosarcoma receiving neoadjuvant chemotherapy were identified. We did not find that P16 expression was correlated with sex status, histologic subtype, and tumor site (P > .1). P16 expression was found to be significantly associated with a "good" response to neoadjuvant chemotherapy (OR = 4.69, P < .001). A significant relationship was observed between p16 expression and pathologic complete response after neoadjuvant chemotherapy using multivariate analysis (OR = 9.63, P = .001). The expression of the P16 was not associated with clinical outcomes in overall survival (OS) and disease-free survival (DFS) by multivariate analysis (OS: P = .448; DFS: P = .263).

CONCLUSIONS

The use of P16 expression could become a promising predictive biomarker of the response to neoadjuvant chemotherapy in the white population with high-grade osteosarcoma. However, it was not correlated with the prognosis of patients in OS and DFS. More clinical researches are very essential in Asians in the future.

Pediatric Sarcomas

Pediatric sarcomas are a heterogeneous group of tumors accounting for approximately 10% of childhood solid tumors. Treatment is focused on multimodality therapy, which has improved the prognosis over the past two decades. Current regimens focus on decreasing treatment for low-risk patients to decrease the long-term side effects while maximizing therapy for patients with metastatic disease to improve survival. Pediatric sarcomas can be divided into soft tissue sarcomas and osseous tumors. Soft tissue sarcomas are further delineated into rhabdomyosarcomas, which affect young children and nonrhabdomyosarcomas, which are most common in adolescents. The most common bone sarcomas are osteosarcomas and Ewing's sarcoma.

Assessing the Prognostic Significance of Histologic Response in Osteosarcoma: A Comparison of Outcomes on CCG-782 and INT0133-A Report From the Children's Oncology Group Bone Tumor Committee

BACKGROUND

The prognostic value of histologic response for osteosarcoma may have changed with induction chemotherapy schedules over time. We hypothesized that the increased intensity of induction therapy provided on INT0133 compared to the Children's Cancer Group study CCG-782 would diminish the impact of histologic response on the risk of events after definitive surgery.

METHODS

Retrospective analysis was performed for patients aged <22 with newly diagnosed nonmetastatic osteosarcoma enrolled on CCG-782 and INT0133. Clinical factors were evaluated for association with response and outcome. Good response was defined as <5% viable tumor at resection. Associations of response, study, and postdefinitive surgery event-free survival (EFS-DS) were determined using Cox proportional hazard models. EFS-DS was estimated by Kaplan-Meier methodology.

RESULTS

Data were available for 814 patients (206 CCG-782, 608 INT0133). For good responders, 10-year EFS-DS (±SE) was 75.4% ± 7.7% for CCG-782 and 70.8% ± 3.1% for INT0133. For poor responders, 10-year EFS-DS was 39.9% ± 4.9% for CCG-782 and 58.4% ± 3.1% for INT0133. Histologic response predicted outcome across studies (P < 0.0001). Significant interaction between study and histologic response was observed for EFS-DS (P = 0.011). Using proportional hazards regression, INT0133 poor responders had less risk of events compared to CCG-782 poor responders (relative hazard ratio (RHR) = 0.6:1), but good responders on INT0133 had a greater risk of events compared to CCG-782 good responders (RHR = 1.53:1).

CONCLUSION

We observed an inverse relationship between the predictive value of tumor necrosis and intensity of induction therapy, raising questions about the true prognostic value of histologic response. This highlights the need for novel markers to develop strategies for treatment in future trials.