Chordoma: the nonsarcoma primary bone tumor

Surgical management of chondrosarcomas of the skull-base and temporal bone

OBJECTIVES

To analyze the overall long-term outcome of surgically treated skull base and temporal bone chondrosarcomas.

METHODS

The medical records of patients with surgically treated skull base and temporal bone chondrosarcomas between 1983 and 2024 were thoroughly evaluated.

RESULTS

Out of a total of over 5000 skull base surgeries performed at our center, only 29 patients had histopathologically confirmed chondrosarcomas of the skull base and temporal bone. The mean of patients age was 45.6, and the male-to-female ratio was 1.9:1. The most common symptoms included hearing loss (58.6%), tinnitus (41.4%), diplopia (31%), dysphonia (24.1%), dysphagia (20.7%), vertigo (10.3%), and dizziness (10.3%). The most frequent locations of lesions among the 29 patients are as follows: petroclival region (34.5%), jugular foramen (27.6%), petrous apex (17.2%), middle ear (13.8%), others (3.4%). TO, IFTA, IFTB, IFTC, POTS, and combined surgical approaches were commonly used. The rate of gross total removal and recurrence was 82.6% and 13.8% respectively. The follow-up duration of 6 patients was more than five years and less than ten years whereas ten patients had more than ten years of follow-up.

CONCLUSIONS

Chondrosarcoma of the skull base and temporal bone is a very rare pathology. Due to its multiple potential sites of origin and histological specificity, it presents us with significant challenges. Gross total removal is the primary treatment for chondrosarcoma of the skull base and temporal bone. Personalized decision-making should be considered based on the following aspects: tumor, patient, and surgeon's factors. Postoperative radiation therapy is complementary to surgical treatment in grades II and III lesions to achieve long-term survival.

Evaluation of cranial nerve involvement in chordomas and chondrosarcomas: a retrospective imaging study

PURPOSE

Cranial nerve involvement (CNI) influences the treatment strategies and prognosis of head and neck tumors. However, its incidence in skull base chordomas and chondrosarcomas remains to be investigated. This study evaluated the imaging features of chordoma and chondrosarcoma, with a focus on the differences in CNI.

METHODS

Forty-two patients (26 and 16 patients with chordomas and chondrosarcomas, respectively) treated at our institution between January 2007 and January 2023 were included in this retrospective study. Imaging features, such as the maximum diameter, tumor location (midline or off-midline), calcification, signal intensity on T2-weighted image, mean apparent diffusion coefficient (ADC) values, contrast enhancement, and CNI, were evaluated and compared using Fisher's exact test or the Mann-Whitney U-test. The odds ratio (OR) was calculated to evaluate the association between the histological type and imaging features.

RESULTS

The incidence of CNI in chondrosarcomas was significantly higher than that in chordomas (63% vs. 8%, P < 0.001). An off-midline location was more common in chondrosarcomas than in chordomas (86% vs. 13%; P < 0.001). The mean ADC values of chondrosarcomas were significantly higher than those of chordomas (P < 0.001). Significant associations were identified between chondrosarcomas and CNI (OR = 20.00; P < 0.001), location (OR = 53.70; P < 0.001), and mean ADC values (OR = 1.01; P = 0.002).

CONCLUSION

The incidence of CNI and off-midline location in chondrosarcomas was significantly higher than that in chordomas. CNI, tumor location, and the mean ADC can help distinguish between these entities.

Role of immunotherapy in treatment refractory chordomas: review of current evidence

Introduction

Chordomas are aggressive tumors that are thought to arise from remnants of the embryological notochord. They can arise along the ventromedial aspect of the sacrum, mobile spine, and clivus-with most cases occurring in the sacrum or skull base. Despite surgery and radiation, chordomas often progress and become refractory to further treatment. The high recurrence rate of chordomas has created an urgent need to develop new systemic treatment options. Recent case reports and clinical trials have highlighted the use of immunotherapy for refractory chordomas. In this review, we summarize the results of these studies and discuss the potential role of immunotherapy for chordomas.

Methods

The PUBMED database was queried for studies mentioning both "Chordoma" and "Immunotherapy." All case series and case reports that involved administration of an immunotherapy for chordoma were included. Additional studies that were found during literature review were added. ClinicalTrials.Gov was queried for studies mentioning both "Chordoma" and "Immunotherapy." The final cohort consisted of all clinical trials that utilized immunotherapy for chordomas of any location.

Results

Eight case reports and series detailing the use of immunotherapy for treatment refractory chordoma were identified. Most patients received immunotherapy targeting the PD-1/PD-L1 interaction, and two patients received therapy targeting this interaction along with the tyrosine kinase inhibitor pazopanib. One patient received a vaccine derived from autologous tumor cells, and one patient received a viral vector that downregulated the effect of TGF-beta. One clinical trial utilized a brachyury vaccine in conjunction with standard of care radiotherapy.

Conclusions

Immunotherapy for chordoma is a promising area of investigation with increasing, but small, numbers of case series and clinical trials. Despite challenges in patient accrual, future directions in chordoma immunotherapy may lie in vaccine-based therapies and immune checkpoint inhibitors. Understanding chordoma heterogeneity and microenvironment will likely elucidate important chordoma features that will inform future clinical trial design.

Unraveling molecular signatures in rare bone tumors and navigating the cancer pathway landscapes for targeted therapeutics

Rare cancers (RCs), which account for over 20% of cancer cases, face significant research and treatment challenges due to their limited prevalence. This results in suboptimal outcomes compared to more common malignancies. Rare bone tumors (RBTs) constitute 5-10% of rare cancer cases and pose unique diagnostic complexities. The therapeutic potential of anti-cancer drugs for RBTs remains largely unexplored. Identifying molecular alterations in cancer-related genes and their associated pathways is essential for precision medicine in RBTs. Small molecule inhibitors and monoclonal antibodies targeting specific RBT-associated proteins show promise. Ongoing clinical trials aim to define RBT biomarkers, subtypes, and optimal treatment contexts, including combination therapies and immunotherapeutic agents. This review addresses the challenges in diagnosing, treating, and studying RBTs, shedding light on the current state of RBT biomarkers, potential therapeutic targets, and promising inhibitors. Rare cancers demand attention and innovative solutions to improve clinical outcomes.

The Use of Proton and Carbon Ion Radiation Therapy for Sarcomas

The unique physical and biological characteristics of proton and carbon ions allow for improved sparing of normal tissues, decreased integral dose to the body, and increased biological effect through high linear energy transfer. These properties are particularly useful for sarcomas given their histology, wide array of locations, and age of diagnosis. This review summarizes the literature and describes the clinical situations in which these heavy particles have advantages for treating sarcomas.

Nasopharyngeal Chordoma: A Case Report

Chordoma is a rare malignant neoplasm arising from remnants of primitive notochord. The most common location for chordoma is in the sacrum. This case presents a 10-year-old medically free male who came to the ENT clinic with the impression of adenoid hypertrophy. After further investigations, including imaging and biopsy, it was found to be a nasopharyngeal chordoma. Our aim, in this case, is to increase the suspension of differential diagnosis of nasopharyngeal masses other than adenoid hypertrophy. In addition, it highlights the importance of imaging in the evaluation of nasopharyngeal masses.

Investigating the Effects of Chordoma Cell-Derived Exosomes on the Tumorigenicity of Nucleus Pulposus Cells

Objective  Interaction of tumor cells with the surrounding environment is essential for tumor growth and progression that eventually leads to metastasis. Growing evidence shows that extracellular vesicles also known as exosomes play a crucial role in signaling between the tumor and its microenvironment. Tumor-derived exosomes have generally protumorigenic effects such as metastasis, hypoxia, angiogenesis, and epithelial-mesenchymal transition. Methods  In this study, exosomes were isolated from a chordoma cell line, MUG-Chor1, and characterized subsequently. The number of exosomes was determined and introduced into the healthy nucleus pulposus (NP) cells for 140 days. The protumorigenic effects of a chordoma cell line-derived exosomes that initiate the tumorigenesis on NP cells were investigated. The impact of tumor-derived exosomes on various cellular events including cell cycle, migration, proliferation, apoptosis, and viability has been studied by treating NP cells with chordoma cell-line-derived exosomes cells. Results  Upon treatment with exosomes, the NP cells not only gained a chordoma-like morphology but also molecular characteristics such as alterations in the levels of certain gene expressions. The migratory and angiogenic capabilities of NP cells increased after treatment with chordoma-derived exosomes. Conclusion  Based on our findings, we can conclude that exosomes carry information from tumor cells and may exert tumorigenic effects on nontumorous cells.

SIRT5 promote malignant advancement of chordoma by regulating the desuccinylation of c-myc

Chordoma is a relatively rare and locally aggressive malignant tumor. Sirtuin (SIRT)5 plays pivotal roles in various tumors, but the role of SIRT5 in chordoma has not been found. This study was performed to investigate the regulatory effects of SIRT5 on cell proliferation, migration, and invasion and the underlying mechanism in chordoma. A xenograft tumor mouse model was established to assess tumor growth. Reverse transcription-quantitative polymerase chain reaction was used to analyze the mRNA levels of SIRT5 and c-myc. The effects of SIRT5 and c-myc on cell proliferation, migration, and invasion of chordoma cells were detected by cell counting kit-8, colony formation, and Transwell assays. The interaction between SIRT5 and c-myc was evaluated by co-immunoprecipitation (IP) assay. The succinylation of c-myc was analyzed by IP and Western blot. The results showed that SIRT5 expression was upregulated in chordoma tissues and cells. SIRT5 interacted with c-myc to inhibit the succinylation of c-myc at K369 site in human embryonic kidney (HEK)-293T cells. Silencing of SIRT5 suppressed the cell proliferation, migration, and invasion of chordoma cells, while the results were reversed after c-myc overexpression. Moreover, silencing SIRT5 suppressed tumor growth in mice. These findings suggested that SIRT5 promoted the malignant advancement of chordoma by regulating the desuccinylation of c-myc.

Twenty-year outcome of prevalence, incidence, mortality and survival rate in patients with malignant bone tumors

Malignant bone tumors are a group of rare malignant tumors and our study aimed to update the recent epidemiologic estimates based on the Surveillance, Epidemiology and End Results database. Patients diagnosed with malignant bone tumors from 2000 to 2019 were included and their characteristics were retrospectively described. The limited-duration prevalence, annual age-adjusted incidence and mortality were calculated, and the annual percentage changes were analyzed to quantify the rate change. Finally, observed survival and relative survival rate were illustrated. Subgroup analysis across tumor type, age, gender, tumor Grade, primary tumor site and stage was also performed. As for results, a total of 11 655 eligible patients with malignant bone tumor were selected. Osteosarcoma was the most common tumor type, followed by chondrosarcoma, Ewing sarcoma and chordoma. The estimated limited-duration prevalence of malignant bone tumors increased from 2000 (0.00069%) to 2018 (0.00749%). Steady age-adjusted incidence was observed in all patients during the study period while the highest rate occurred in osteosarcoma. Mortality rates differed in subgroups while elder patients (older than 64 years) presented the highest mortality rate compared to other age groups. In all bone tumors, the 10-year observed survival and relative survival rates were 58.0% and 61.9%, respectively. Chondrosarcoma patients had the best survival outcome, followed by osteosarcoma, Ewing sarcoma, chordoma and other bone tumors. In conclusion, different epidemiologic performance in incidence and mortality was observed across tumor type as well as other demographic and clinicopathological variables, which provide potential suggestion for further adjustment of medical resource.

Activation of Wnt Pathway Suppresses Growth of MUG-Chor1 Chordoma Cell Line

Chordoma as a malignant bone tumor, occurs along the axial skeleton and does not have an effective therapy. Brachyury, which is a crucial player for the formation of early embryonic notochord, is abundantly found in both sporadic and familial chordoma. During embryonic development, Brachyury expression was reported to be regulated by the Wnt pathway. The objective of the study is to investigate the role of Wnt signaling in a human chordoma cell line in terms of proliferation, survival, and invasiveness. We tried to elucidate the signaling events that regulate Chordoma cancer. In this regard, Wnt pathway was activated or inhibited using various strategies including small molecules, siRNA-based knockdown and overexpression applications. The results indicated the negative regulatory effect of Wnt signaling activity on proliferation and migration capacity of the chordoma cells. It was revealed that when GSK3β was inhibited, the Wnt pathway was activated and negatively regulated T/Bra expression. Activity of the Wnt pathway caused cell cycle arrest, reduced migration potential of the cells, and led to cell death. Therefore, the present study suggests that the Wnt pathway plays a key role in suppressing the proliferation and invasive characteristics of human chordoma cells and has a great potential as a therapeutic target in further clinical studies.

Assessing survival outcomes and complication profiles following surgical excision and radiotherapy as interventions for skull base chordoma: a systematic review of operative margins and surgical approaches

INTRODUCTION

Despite their precarious behavioral classification (benign and low grade on histopathology yet behaviorally malignant), great strides have been taken to improve prognostication and treatment paradigms for patients with skull base chordoma. With respect to surgical techniques, lateral transcranial (TC) approaches have traditionally been used, however endoscopic endonasal approaches (EEA) have been advocated for midline lesions. Nonetheless, due to the rarity of this pathology (0.2% of all intracranial neoplasms), investigations within the literature remain limited to small retrospective series. Furthermore, radiotherapeutic treatments investigated to date have proven largely ineffective.

METHODS

Accordingly, we performed a systematic review in order to profile surgical and survival outcomes for skull base chordoma. Fixed and random-effect meta-analyses were performed for categorical variables including GTR, STR, 5-year OS, 10-year OS, 5-year PFS, and 10-year PFS. Additionally, we pooled eligible studies for formal meta-analysis to compare outcomes by surgical approach (lateral versus midline). Statistical analyses were performed using R Studio 'metafor' package or Cochrane Review Manager. Furthermore, meta-analysis of pooled mortality rates and sub-analyses of operative margin and surgical complications were used to compare midline versus lateral approaches via the Mantel-Haenszel method. We considered all p-values < 0.05 to be statistically significant.

RESULTS

Following the systematic search and screen, 55 studies published between 1993 and 2022 reporting data for 2453 patients remained eligible for analysis. Sex distribution was comparable between males and females, with a slight predominance of male-identifying patients (0.5625 [95% CI: 0.5418; 0.3909]). Average age at diagnosis was 42.4 ± 12.5 years, while average age of treatment initiation was 43.0 ± 10.6 years. Overall, I2 value indicated notable heterogeneity across the 55 studies [I2 = 56.3% (95%CI: 44.0%; 65.9%)]. With respect to operative margins, the rate of GTR was 0.3323 [95% CI: 0.2824; 0.3909], I2 = 91.9% [95% CI: 90.2%; 93.4%], while the rate of STR was significantly higher at 0.5167 [95% CI: 0.4596; 0.5808], I2 = 93.1% [95% CI: 91.6%; 94.4%]. The most common complication was CSF leak (5.4%). In terms of survival outcomes, 5-year OS rate was 0.7113 [95% CI: 0.6685; 0.7568], I2 = 91.9% [95% CI: 90.0%; 93.5%]. 10-year OS rate was 0.4957 [95% CI: 0.4230; 0.5809], I2 = 92.3% [95% CI: 89.2%; 94.4%], which was comparable to the 5-year PFS rate of 0.5054 [95% CI: 0.4394; 0.5813], I2 = 84.2% [95% CI: 77.6%; 88.8%] and 10-yr PFS rate of 0.4949 [95% CI: 0.4075; 0.6010], I2 = 14.9% [95% CI: 0.0%; 87.0%]. There were 55 reported deaths for a perioperative mortality rate of 2.5%. The relative risk for mortality in the midline group versus the lateral approach group did not indicate any substantial difference in survival according to laterality of approach (-0.93 [95% CI: -1.03, -0.97], I2 = 95%, (p < 0.001).

CONCLUSION

Overall, these results indicate good 5-year survival outcomes for patients with skull base chordoma; however, 10-year prognosis for skull base chordoma remains poor due to its radiotherapeutic resistance and high recurrence rate. Furthermore, mortality rates among patients undergoing midline versus lateral skull base approaches appear to be equivocal.

Targeting epigenetic aberrations of sarcoma in CRISPR era

Sarcomas are rare malignancies that exhibit diverse biological, genetic, morphological, and clinical characteristics. Genetic alterations, such as gene fusions, mutations in transcriptional machinery components, histones, and DNA methylation regulatory molecules, play an essential role in sarcomagenesis. These mutations induce and/or cooperate with specific epigenetic aberrations required for the growth and maintenance of sarcomas. Appropriate mouse models have been developed to clarify the significance of genetic and epigenetic interactions in sarcomas. Studies using the mouse models for human sarcomas have demonstrated major advances in our understanding the developmental processes as well as tumor microenvironment of sarcomas. Recent technological progresses in epigenome editing will not only improve the studies using animal models but also provide a direct clue for epigenetic therapies. In this manuscript, we review important epigenetic aberrations in sarcomas and their representative mouse models, current methods of epigenetic editing using CRISPR/dCas9 systems, and potential applications in sarcoma studies and therapeutics.

Intensity-modulated radiotherapy for the management of primary and recurrent chordomas: a retrospective long-term follow-up study

Background

Chordomas have a high risk of recurrence. Radiotherapy (RT) is required as adjuvant therapy after resection. Sufficient radiation doses for local control (LC) can be achieved using either particle therapy, if this technology is available and feasible, or intensity-modulated radiotherapy.

Materials and methods

57 patients (age, 11.8-81.6 years) with chordomas of the skull base, spine and pelvis who received photon radiotherapy between 1995 and 2017 were enrolled in the study. Patients were treated at the time of initial diagnosis (68.4%) or during recurrence (31.6%). 44 patients received adjuvant radiotherapy and 13 received definitive radiotherapy. The median total dose to the physical target volume was 70 Gy equivalent dose in 2 Gy fractions (EQD2) (range: 54.7-82.5) in 22-36 fractions.

Results

LC was 76.4%, 58.4%, 46.7% and 39.9% and overall survival (OS) was 98.3%, 89%, 76.9% and 47.9% after 1, 3, 5 and 10 years, respectively, with a median follow-up period of 6.5 years (range, 0.5-24.3 years). Age, dose and treatment concept (post-operative or definitive) were significant prognostic factors for OS. Primary treatment, macroscopic tumour at RT and size of the irradiated volume were statistically significant prognostic factors for LC.

Conclusion

Photon treatment is a safe and effective treatment for chordomas if no particle therapy is available. The best results can be achieved against primary tumours if the application of curative doses is possible due to organs at risk in direct proximity. We recommend high-dose radiotherapy, regardless of the resection status, as part of the initial treatment of chordoma, using the high conformal radiation technique if particle therapy is not feasible.

Activity of pemetrexed in pre-clinical chordoma models and humans

Chordomas are rare slow growing tumors, arising from embryonic remnants of notochord with a close predilection for the axial skeleton. Recurrence is common and no effective standard medical therapy exists. Thymidylate synthase (TS), an intracellular enzyme, is a key rate-limiting enzyme of DNA biosynthesis and repair which is primarily active in proliferating and metabolically active cells. Eighty-four percent of chordoma samples had loss of TS expression which may predict response to anti-folates. Pemetrexed suppresses tumor growth by inhibiting enzymes involved in folate metabolism, resulting in decreased availability of thymidine which is necessary for DNA synthesis. Pemetrexed inhibited growth in a preclinical mouse xenograft model of human chordoma. We report three cases of metastatic chordoma that had been heavily treated previously with a variety of standard therapies with poor response. In two cases, pemetrexed was added and objective responses were observed on imaging with one patient on continuous treatment for > 2 years with continued shrinkage. One case demonstrated tumor growth after treatment with pemetrexed. The two cases which had a favorable response had a loss of TS expression, whereas the one case with progressive disease had TS present. These results demonstrate the activity of pemetrexed in recurrent chordoma and warrant a prospective clinical trial which is ongoing (NCT03955042).

Proton or Carbon Ion Therapy for Skull Base Chordoma: Rationale and First Analysis of a Mono-Institutional Experience

Background: Skull base chordomas are radio-resistant tumors that require high-dose, high-precision radiotherapy, as can be delivered by particle therapy (protons and carbon ions). We performed a first clinical outcome analysis of particle therapy based on the initial 4-years of operation. Methods: Between August 2017 and October 2021, 44 patients were treated with proton (89%) or carbon ion therapy (11%). Prior gross total resection had been performed in 21% of lesions, subtotal resection in 57%, biopsy in 12% and decompression in 10%. The average prescription dose was 75.2 Gy RBE in 37 fractions for protons and 66 Gy RBE in 22 fractions for carbon ions. Results: At a median follow-up of 34.3 months (range: 1–55), 2-, and 3-year actuarial local control rates were 95.5% and 90.9%, respectively. The 2-, and 3-year overall and progression-free survival rates were 97.7%, 93.2%, 95.5% and 90.9%, respectively. The tumor volume at the time of particle therapy was highly predictive of local failure (p < 0.01), and currently, there is 100% local control in patients with tumors < 49 cc. No grade ≥3 toxicities were observed. There was no significant difference in outcome or side effect profile seen for proton versus carbon ion therapy. Five patients (11.4%) experienced transient grade ≤2 radiation-induced brain changes. Conclusions: The first analysis suggests the safety and efficacy of proton and carbon ion therapy at our center. The excellent control of small to mid-size chordomas underlines the effectiveness of particle therapy and importance of upfront maximum debulking of large lesions.

Intrasellar Chordoma Mimicking Pituitary Macroadenoma with Hyperprolactinemia and Hypopituitarism: Clinical Images with a Surgical Video

A purely intrasellar chordoma is rare among skull base chordomas and is recognized as originating from ectopic embryological notochord located in the sella turcica. In view of its rarity and nonspecific symptoms, clinicians may misdiagnose intrasellar chordoma as pituitary adenoma based on preoperative radiographic images. In this report, we present an intrasellar chordoma that clinically mimicked pituitary macroadenoma with hyperprolactinemia and hypopituitarism and was successfully resected by endoscopic endonasal transsphenoidal surgery. This case demonstrated radiographic features that chordoma should be suspected in sellar lesions. The enlarged sellar with thinned remodeled bone without clival destruction was firstly reminiscent of pituitary adenoma, whereas the very high signal on T2-weighted images and heterogeneous enhancement characteristically suggested chordoma. This rare diagnosis must be considered in the preoperative evaluation of sellar lesions because it can affect how the neurosurgeon prepares for surgery and the surgical goals.

Impact of silencing eEF2K expression on the malignant properties of chordoma

BACKGROUND

Eukaryotic elongation factor 2 kinase (eukaryotic elongation factor 2 kinase, eEF2K) is a calcium calmodulin dependent protein kinase that keeps the highest energy consuming cellular process of protein synthesis under check through negative regulation. eEF2K pauses global protein synthesis rates at the translational elongation step by phosphorylating its only kown substrate elongation factor 2 (eEF2), a unique translocase activity in ekaryotic cells enabling the polypeptide chain elongation. Therefore, eEF2K is thought to preserve cellular energy pools particularly upon acute development of cellular stress conditions such as nutrient deprivation, hypoxia, or infections. Recently, high expression of this enzyme has been associated with poor prognosis in an array of solid tumor types. Therefore, in a growing number of studies tremendous effort is being directed to the development of treatment methods aiming to suppress eEF2K as a novel therapeutic approach in the fight against cancer.

METHODS

In our study, we aimed to investigate the changes in the tumorigenicity of chordoma cells in presence of gene silencing for eEF2K. Taking a transient gene silencing approach using siRNA particles, eEF2K gene expression was suppressed in chordoma cells.

RESULTS

Silencing eEF2K expression was associated with a slight increase in cellular proliferation and a decrease in death rates. Furthermore, no alteration in the sensitivity of chordoma cells to chemotherapy was detected in response to the decrease in eEF2K expression which intriguingly promoted suppression of cell migratory and invasion related properties.

CONCLUSION

Our findings indicate that the loss of eEF2K expression in chordoma cell lines results in the reduction of metastatic capacity.

LOC554202 contributes to chordoma progression by sponging miR-377-3p and up-regulating SMAD3

Chordoma is a rare malignant bone tumor originating from the remnants of the notochord. Here, the role of long noncoding LOC554202 in chordoma progression and its associated mechanism were explored. Cell proliferation was analyzed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5 diphenyltetrazolium bromide and colony formation assays. Flow cytometry was conducted to analyze cell apoptosis rate. The migration and invasion of chordoma cells were analyzed by transwell migration and invasion assays and wound healing assays. A xenograft tumor model was established in nude mice to explore the role of LOC554202 in regulating tumor growth in vivo . The interaction between microRNA-377-3p (miR-377-3p) and LOC554202 or sekelsky mothers against d PP (SMAD) family member 3 (SMAD3) was verified by dual-luciferase reporter and RNA immunoprecipitation assays. The glycolytic rate of chordoma cells was analyzed using glucose assay kit, lactic acid kit and ApoSENSOR ADP/ATP ratio assay kit. LOC554202 expression was upregulated in chordoma tissues and cell lines. LOC554202 silencing suppressed the proliferation, migration and invasion and induced the apoptosis of chordoma cells. LOC554202 knockdown restrained xenograft tumor growth in vivo . miR-377-3p was confirmed as a target of LOC554202, and miR-377-3p silencing largely overturned LOC554202 knockdown-mediated anti-tumor effects in chordoma cells. miR-377-3p interacted with the 3' untranslated region (3'UTR) of SMAD3 and miR-377-3p overexpression-mediated antitumor effects in chordoma cells were largely attenuated by SMAD3 overexpression. LOC554202 could positively regulate SMAD3 expression by sponging miR-377-3p in chordoma cells. LOC554202 contributed to the glycolysis of chordoma cells by targeting binding to miR-377-3p/SMAD3 axis. LOC554202 facilitated the proliferation, migration, invasion and glycolysis and inhibited the apoptosis of chordoma cells by mediating miR-377-3p/SMAD3 axis.

Management of Chordoma of the Sacrum and Mobile Spine

➢

Chordomas account for 1% to 4% of primary tumors of the spine and sacrum.

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En bloc resection is the preferred surgical treatment for the management of chordomas.

➢

Proton beam radiation is increasingly being used as a postoperative radiation modality for the treatment of chordomas.

Multi-spectral immunofluorescence evaluation of the myeloid, T cell, and natural killer cell tumor immune microenvironment in chordoma may guide immunotherapeutic strategies

Background

Chordoma is a rare, invasive, and devastating bone malignancy of residual notochord tissue that arises at the skull base, sacrum, or spine. In order to maximize immunotherapeutic approaches as a potential treatment strategy in chordoma it is important to fully characterize the tumor immune microenvironment (TIME). Multispectral immunofluorescence (MIF) allows for comprehensive evaluation of tumor compartments, molecular co-expression, and immune cell spatial relationships. Here we implement MIF to define the myeloid, T cell, and natural killer (NK) cell compartments in an effort to guide rational design of immunotherapeutic strategies for chordoma.

Methods

Chordoma tumor tissue from 57 patients was evaluated using MIF. Three panels were validated to assess myeloid cell, T cell, and NK cell populations. Slides were stained using an automated system and HALO software objective analysis was utilized for quantitative immune cell density and spatial comparisons between tumor and stroma compartments.

Results

Chordoma TIME analysis revealed macrophage infiltration of the tumor parenchyma at a significantly higher density than stroma. In contrast, helper T cells, cytotoxic T cells, and T regulatory cells were significantly more abundant in stroma versus tumor. T cell compartment infiltration more commonly demonstrated a tumor parenchymal exclusion pattern, most markedly among cytotoxic T cells. NK cells were sparsely found within the chordoma TIME and few were in an activated state. No immune composition differences were seen in chordomas originating from diverse anatomic sites or between those resected at primary versus advanced disease stage.

Conclusion

This is the first comprehensive evaluation of the chordoma TIME including myeloid, T cell, and NK cell appraisal using MIF. Our findings demonstrate that myeloid cells significantly infiltrate chordoma tumor parenchyma while T cells tend to be tumor parenchymal excluded with high stromal infiltration. On average, myeloid cells are found nearer to target tumor cells than T cells, potentially resulting in restriction of T effector cell function. This study suggests that future immunotherapy combinations for chordoma should be aimed at decreasing myeloid cell suppressive function while enhancing cytotoxic T cell and NK cell killing.

Chordoma of the Clivus with Metastasis to Femur

Chordomas are aggressive and invasive tumors that are notoriously famous for their recurrence and metastasis. They present with diverse manifestations, usually with lower cranial nerve involvement. Here, we present the first reported case of chondroid chordoma with femur metastasis. A 71-year-old lady presented to us with a headache and diplopia. MRI of the brain revealed an enhanced broad and destructive mass in the infrasellar region with complete destruction of the clivus, right cavernous sinus. She underwent multiple surgeries along with gamma knife and proton therapy. The patient later presented with a trochanteric fracture and needed a hip replacement. Biopsy curettage of the femur lesion revealed a chondroid chordoma of the femur. The patient died later of a chest infection. Multimodality treatment is required in chordoma management, including surgery, gamma knife, and proton therapy. A firm discerning eye is required in the elderly toward metastatic spread to the femur in cases presenting with fractures of long bones.

Differences in stromal component of chordoma are associated with contrast enhancement in MRI and differential gene expression in RNA sequencing

Chordoma is a malignant bone neoplasm demonstrating notochordal differentiation and it frequently involves axial skeleton. Most of chordomas are conventional type with varying amount of myxoid stroma. Previously known prognostic factors for conventional chordoma are not specific for chordoma: old age, metastasis, tumor extent, and respectability. Here, we aimed to investigate the histologic, radiologic, and transcriptomic differences in conventional chordoma based on the stromal component. A total of 45 patients diagnosed with conventional chordoma were selected between May 2011 and March 2020 from a single institution. Electronic medical records, pathology slides, and pretreatment magnetic resonance imaging (MRI) scans were reviewed. Of the 45 patients, ten cases (4 stroma-rich and 6 stroma-poor tumor) were selected for RNA sequencing, and available cases in the remainder were used for measuring target gene mRNA expression with qPCR for validation. Differential gene expression and gene set analysis were performed. Based on histologic evaluation, there were 25 (55.6%) stroma-rich and 20 (44.4%) stroma-poor cases. No clinical differences were found between the two groups. Radiologically, stroma-rich chordomas showed significant signal enhancement on MRI (72.4% vs 27.6%, p = 0.002). Upregulated genes in stroma-rich chordomas were cartilage-, collagen/extracellular matrix-, and tumor metastasis/progression-associated genes. Contrarily, tumor suppressor genes were downregulated in stroma-rich chordomas. On survival analysis, Kaplan–Meier plot was separated that showed inferior outcome of stroma-rich group, although statistically insignificant. In conclusion, the abundant stromal component of conventional chordoma enhanced well on MRI and possibly contributed to the biological aggressiveness that supported by transcriptomic characteristics. Further extensive investigation regarding radiologic-pathologic-transcriptomic correlation in conventional chordoma in a larger cohort could verify additional clinical significance.

An Unusual Chordoma of the Odontoid Process: A Case Report and Literature Review

The aim of this study is to present a rare case of chordoma in the odontoid process in which the tumor involved the odontoid process and compressed the spinal cord at the craniocervical junction. We report on the effectiveness and successful outcome of anterior microscopic tumor resection combined with posterior occipitocervical fixation and review the current standard treatment. A 39-year-old man presented with sudden dyspnea and quadriparesis caused by an unknown tumor compression at C2. Radiographic examination revealed a large destructive mass at C2 and heterogeneous enhancement. The patient received urgent surgical intervention by microscopic-assisted anterior tumor resection and posterior spinal fixation from the occiput to the C5 level. The pathohistologic reports for cytokeratins, epithelial membrane antigen, and S-100 protein were positive. The final diagnosis was chordoma of the odontoid process. At the 2-year follow-up, the patient's condition had improved, and a postoperative MRI showed no indication of tumor regrowth. Chordoma of the odontoid process or C2 body is very rare. The current standard management is wide tumor resection to prevent recurrence. The combined approach of anterior tumor resection with microscopic assistance and posterior stabilization of the occiput to C5 is the optimal treatment for this condition.

Prevalence, Risk Factors, and Prognostic Factors of Primary Malignant Bone Neoplasms with Bone Metastasis at Initial Diagnosis: A Population-Based Study

Background. Bone metastasis (BM) has been proven to be responsible for the poor prognosis of primary malignant bone neoplasms (PMBNs). We aimed to identify the prevalence, risk factors, and prognostic factors for PMBNs patients with BM based on the Surveillance, Epidemiology, and End Results (SEER) database. Methods. 4,758 patients diagnosed with PMBNs from 2010 to 2018 were selected from the SEER database. All patients were divided into two groups: the BM group or the non-BM group. Pearson’s chi-square test and Fisher’s exact method were used to assess baseline characteristics, and logistic regression analysis was applied to assess risk factors. In addition, a nomogram was constructed based on the results of Cox regression analysis among 227 patients with BM. The good performance and clinical applicability of the nomogram were tested by the concordance index, operating characteristic curve, area under the curve, calibration curves, and decision curve analysis. Results. 227 (4.8%) patients had metastasis to bone at diagnosis. Primary site outside the extremities (axial: odds ratio, $\text{OR}=1.770$ ; others: $\text{OR}=1.951$ ), Ewing sarcoma ( $\text{OR}=2.845$ ), larger tumor size (5–8 cm: $\text{OR}=3.403$ ; >8 cm: $\text{OR}=5.562$ ), tumor extension beyond the periosteum ( $\text{OR}=2.477$ ), and regional lymph node metastasis ( $\text{OR}=2.900$ ) were associated with a higher risk of BM at the initial diagnosis of PMBNs. Five independent prognostic factors were found in the survival analysis: pathological type (chondrosarcoma vs. osteosarcoma: hazard ratio, $\text{HR}=0.342$ ; Ewing sarcoma vs. osteosarcoma: $\text{HR}=0.592$ ; and chordoma vs. osteosarcoma: $\text{HR}=0.015$ ), marital status ( $\text{HR}=2.457$ ), pulmonary metastasis ( $\text{HR}=1.934$ ), surgery at the primary site ( $\text{HR}=0.164$ ), and chemotherapy ( $\text{HR}=0.084$ ). A nomogram based on these prognostic factors could be a good predictor of cancer-specific survival. Conclusions. We identified the prevalence, risk factors, and prognostic factors correlated with BM in PMBNs patients. The related nomogram could be a practical tool for therapeutic decision-making and individual counseling.

Coexpression of HHLA2 and PD-L1 on Tumor Cells Independently Predicts the Survival of Spinal Chordoma Patients

Background

Immunotherapy only achieves efficacy in some cancer patients, and less is known about other immune checkpoint molecules in chordoma. Here, we aimed to determine the expression of PD-L1, HHLA2, B7H3, IDO-1 and Galectin-9 in spinal chordoma and evaluated their association with tumor infiltrating lymphocytes (TILs), clinicopathological characteristics and survival of patients.

Methods

Using multiplexed quantitative immunofluorescence (QIF), we simultaneously measured the levels of five different immune checkpoint molecules and major TIL subsets in 92 human spinal chordoma samples.

Results

Tumor HHLA2 and PD-L1 were positive in 80.0% and 86.0% of cases, respectively. However, B7H3, IDO-1 and Galectin-9 positivity on tumor cells were only seen in 21.0% of cases, despite all showing predominantly stromal expression. Coexpression of these QIF markers in the tumor compartment was scarcely detected except for PD-L1 and HHLA2, which was observed in 69.6% of cases. While tumoral HHLA2 and stromal B7H3 expressions were associated with an aggressive tumor phenotype, suppressive immune response (specifically including elevated PD-1⁺ TILs level and decreased CD8⁺ TIL density) and poor prognosis, stromal levels of PD-L1 and Galectin-9 predicted the opposite outcomes. Importantly, HHLA2 and PD-L1 coexpression on tumor cells independently predicted both worse local recurrence-free survival and overall survival.

Conclusion

These data provide a better understanding of the immunosuppressive mechanism in chordoma and may be useful for the development of combination or novel immunotherapy approaches aiming to improve therapeutic efficacy and survival.

Targeted delivery of cancer drug paclitaxel to chordomas tumor cells via an RNA nanoparticle harboring an EGFR aptamer

Paclitaxel has been extensively used in clinics for cancer treatment. However, its limited solubility in aqueous solution and high occurrence of side effects have also been widely reported. In this study, we constructed a biocompatible RNA nanoparticle delivery system (3WJ-EGFR_apt) that includes 3WJ (3-way junction) nanoparticle with a size of 4.85 ± 0.59 nm as a backbone and an EGFR (epidermal growth factor receptor) aptamer for specific targeting to chordomas cells, which owns the encapsulation ability of drug paclitaxel (PTX) for cancer therapy. Confocal microscopy and flow cytometry results confirmed 3WJ-EGFR_apt nanoparticle exhibited excellent specific targeting to chordomas cell U-CH2 which is an EGFR(+) cell line; while the 3WJ nanoparticle lose the targeted ability. Both of the two nanoparticles own no sensitivity to lung cancer cell H520 which is an EGFR(-) cell line. Moreover, the 3WJ-EGFR_apt nanoparticle encapsulated drug PTX could enhance the inhibition efficiency of chordomas tumor cells U-CH2 as compared to free PTX alone. This work demonstrates that RNA-3WJ constructed with a targeting aptamer provides a compromising targeted drug delivery ability on chordomas cells for therapeutics.

Metastatic chordoma with pancreatic disease and response to imatinib

A 45-year-old woman presented with a left-sided neck swelling following treatment a year prior for cervical spine chordoma. She had initially been managed surgically with a cervical vertebrectomy and a course of proton beam therapy. Although there had been a degree of residual tissue, her disease remained stable radiologically and clinically. Repeat MRI demonstrated an increasing left paravertebral mass and a head of pancreas metastasis, which shared pathological characteristics with chordoma. Given the advanced metastatic nature of her disease, imatinib was offered with a palliative intent. While waiting for treatment she developed a spinal cord compression, managed with radiotherapy. She commenced imatinib and her disease remained stable for 9 months before progressing clinically and radiologically. This case demonstrates an unusual pattern of metastatic chordoma and provides further rationale for imatinib in such patients.

[Sacrococcygeal chordoma: about a case]

Le chordome sacrococcygien est une entité pathologique rare, rapporté dans seulement moins de 3% des cas. Nous allons rapporter l´observation d´une patiente prise en charge au Centre Régional d'Oncologie d'Oujda au Maroc ayant présenté un chordome sacrococcygien localement avancé. Le traitement a consisté en une radiothérapie exclusive sur la tumeur, la chirurgie d´exérèse n´était pas possible. Actuellement la patiente est à 2 ans de recul, la tumeur est stable sur le plan clinique et radiologique avec un bon état général.

A Giant Sacrococcygeal Chordoma: A Case Report

Sacrococcygeal chordoma is a rare malignant bone tumor. Although there are tough membranes such as the periosteum and presacral fascia (which resist transgression by the tumors), chordoma usually invades the rectal wall. The serious problem with these tumors is the late diagnosis and its high likelihood to become enlarged. The main treatment options for this tumor is surgical resection, radiotherapy, and chemotherapy. Due to the tumor vicinity to important organs such as bladder and its neurovascular structures, it makes surgical excision extremely challenging. The aim of this study is to describe a 50-year-old man with a giant sacrococcygeal mass. The novelty of this case report is the huge and unique size of the tumor which has not reported previously as well the special surgical approaches performed to remove the tumor.

High Red Cell Distribution Width Independently Predicts Adverse Survival in Patients with Newly Diagnosed Skull Base Chordoma

Objective

Accumulating studies report that levels of mean corpuscular volume (MCV) and red cell distribution width (RDW) are associated with outcomes in cancer patients, while studies including MCV and RDW in chordoma are lacking so far. Therefore, our study aims to investigate the prognostic impact of MCV and RDW on survival in skull base chordoma patients.

Methods

Levels of preoperative MCV and RDW in 187 primary skull base chordoma patients were collected. X-tile software was used to find the cutoff values of MCV and RDW. Progression-free survival (PFS) and overall survival (OS) analyses were performed using the Kaplan–Meier methods, Cox analysis, and nomogram model.

Results

Low MCV level (MCV <84.2) was more commonly observed in classical chordoma patients (p=0.022). High RDW level (RDW≥12.7) was correlated with older patient age (p=0.022) and a tough tumor texture (p=0.035). Low MCV level and high RDW level were associated with poor PFS (p=0.045 and 0.007, respectively) and OS (p=0.023 and <0.001, respectively). Multivariate Cox analysis demonstrated that RDW was an independent prognostic indicator for both PFS (p=0.001) and OS (p<0.001). Importantly, a nomogram based on RDW and clinical predictors showed satisfactory performance for PFS and OS prediction (concordance index, C-index: 0.684 and 0.744, respectively).

Conclusion

Our data was first to reveal the prognostic role of RDW in skull base chordoma, and identified the use of RDW may contribute to a more accurate prognosis judgment and personalized treatment decision.

Hemorrhagic Skull Base Chordoma Presenting As Chordoma Apoplexy

Intratumoral hemorrhage/apoplexy in clival chordomas is extremely uncommon, with only 16 reported cases. The average age of patients was 46.2 years and slightly more than half were men. In cases published before 1990, all patients died from their disease without any intervention. Since then, 11 patients have undergone resection by a variety of approaches and there have been no deaths. The diagnosis of skull base chordomas relies on a combination of clinical presentation and radiographic features related to the location and invasion of the tumor. Chordomas presenting with sudden-onset symptoms should alarm the surgeon of a possible hemorrhage. As an illustration of this presentation, we describe a 58-year-old woman who presented with acute-onset headache and cranial nerve deficits. Computed tomography and magnetic resonance imaging demonstrated a hemorrhagic clival lesion with cavernous sinus extension. The patient underwent transsphenoidal resection of the lesion that resulted in the resolution of her symptoms. Histopathological evaluation of the lesion was consistent with chordoma with acute hemorrhagic components. Although intratumoral hemorrhage is rarely detected in chordomas, it should be considered a differential diagnosis of such lesions because prompt recognition and treatment are critical for patient survival.

Combinatorial Natural Killer Cell-based Immunotherapy Approaches Selectively Target Chordoma Cancer Stem Cells

Chordoma is a rare tumor derived from notochord remnants that has a propensity to recur and metastasize despite conventional multimodal treatment. Cancer stem cells (CSC) are implicated in chordoma's resistant and recurrent behavior; thus strategies that target CSCs are of particular interest. Using in vitro cytotoxicity models, we demonstrated that anti-programmed death-ligand 1 (N-601) and anti-epidermal growth factor receptor (cetuximab) antibodies enhanced lysis of chordoma cells by healthy donor and chordoma patient NK cells through antibody-dependent cellular cytotoxicity (ADCC). Treatment of NK cells with an IL-15 superagonist complex (N-803) increased their cytotoxicity against chordoma cells, which was further enhanced by treatment with N-601 and/or cetuximab. PD-L1-targeted chimeric antigen receptor NK cells (PD-L1 t-haNKs) were also effective against chordoma cells. CSCs were preferentially vulnerable to NK cell killing in the presence of N-601 and N-803. Flow cytometric analysis of a chordoma CSC population showed that CSCs expressed significantly more NK activating ligand B7-H6 and PD-L1 than non-CSCs, thus explaining a potential mechanism of selective targeting. These data suggest that chordoma may be effectively targeted by combinatorial NK cell-mediated immunotherapeutic approaches and that the efficacy of these approaches in chordoma and other CSC-driven tumor types should be investigated further in clinical studies.

Skull Base Chordoma: Long-Term Observation and Evaluation of Prognostic Factors after Surgical Resection

BACKGROUND

Skull base chordoma (SBC) is relatively rare and data on its clinical outcome after surgical resection and adjuvant radiotherapy are still limited.

OBJECTIVE

Analyzing the clinical postoperative outcome of SBC patients and defining prognostic factors regarding current treatment modalities.

METHODS AND MATERIAL

In this study, 41 SBC patients from 2001 to 2017 were retrospectively analyzed in this single-center study.

RESULTS

The most common clinical symptoms were headache (63%) and problems concerning vision (54%) like diplopia. The follow-up controls took place from 1 to 192 months. The mean survival time for the patients was 123.37 months (95% CI 90.89-155.86). The 5- and 10-year survival rates were 73.3 and 49%, respectively. Regarding the Karnofsky-Performance Scale (KPS), Cox regression showed a significant relationship between the survival rates in the overall study population and pre-surgery KPS (P = 0.004). This was further supported with a positive significant correlation between the pre-surgery KPS and the KPS at the last follow-up (P = 0.039).

CONCLUSION

Statistical analysis showed that repeat surgical resection and radiotherapy could be prognostic factors. Furthermore, we were able to show that mortality decreased by 4.5% with each 10 points increase of pre-surgery KPS. This could be a major prognostic factor when deciding treatment modalities. Nevertheless, further standardized clinical studies with a larger patient population should be carried out to extrapolate prognostic factors and improve treatment modalities.

DNA Methylation based prognostic subtypes of chordoma tumors in tissue and plasma

BACKGROUND

Chordomas are rare malignant bone cancers of the skull-base and spine. Patient survival is variable and not reliably predicted using clinical factors or molecular features. This study identifies prognostic epigenetic chordoma subtypes that are detected non-invasively using plasma methylomes.

METHODS

Methylation profiles of 68 chordoma surgical samples were obtained between 1996-2018 across three international centres along with matched plasma methylomes where available.

RESULTS

Consensus clustering identified two stable tissue clusters with a disease-specific survival difference that was independent of clinical factors in a multivariate Cox analysis (HR=14.2, 95%CI: 2.1-94.8, p=0.0063). Immune-related pathways with genes hypomethylated at promoters and increased immune cell abundance were observed in the poor-performing "Immune-infiltrated" subtype. Cell-to-cell interaction plus extracellular matrix pathway hypomethylation and higher tumor purity was observed in the better-performing "Cellular" subtype. The findings were validated in additional DNA methylation and RNA sequencing datasets as well as with immunohistochemical staining. Plasma methylomes distinguished chordomas from other clinical differential diagnoses by applying fifty chordoma-versus-other binomial generalized linear models in random 20% testing sets (mean AUROC=0.84, 95%CI: 0.52-1.00). Tissue-based and plasma-based methylation signals were highly correlated in both prognostic clusters. Additionally, leave-one-out models accurately classified all tumors into their correct cluster based on plasma methylation data.

CONCLUSIONS

Here, we show the first identification of prognostic epigenetic chordoma subtypes and first use of plasma methylome-based biomarkers to non-invasively diagnose and subtype chordomas. These results may transform patient management by allowing treatment aggressiveness to be balanced with patient risk according to prognosis.

Craniovertebral junction chordomas: Case series and strategies to overcome the surgical challenge

Introduction:

Chordomas are rare and malignant primary bone tumors. Different strategies have been proposed for chordomas involving the craniovertebral junction (CVJ) compared to other locations. The impossibility to achieve en bloc excision, the impact on stability and the need for proper reconstruction make their surgical management challenging.

Objective:

The objective is to discuss surgical strategies in CVJ chordomas operated in a single-center during a 7 years' experience (2013-2019).

Methods:

Adult patients with CVJ chordoma were retrospectively analyzed. The clinical, radiological, pathological, and surgical data were discussed.

Results:

A total number of 8 patients was included (among a total number of 32 patients suffering from skull base chordoma). Seven patients underwent endoscopic endonasal approach (EEA), and posterior instrumentation was needed in three cases. Three explicative cases were reported: EEA for midline tumor involving lower clivus and upper cervical spine (case 1), EEA and complemental posterior approach for occurred occipitocervical instability (case 2), C2 chordoma which required aggressive bone removal and consequent implant positioning, focusing on surgical planning (timing and type of surgical stages, materials and customization of fixation system) (case 3).

Conclusion:

EEA could represent a safe route to avoid injuries to neurovascular structure in clival locations, while a combined approach could be considered when tumor spreads laterally. Tumor involvement or surgical procedures could give raise to CVJ instability with the need of complementary posterior instrumentation. Thus, a tailored preoperative planning should play a key role, especially when aggressive bone removal and implant positioning are needed.

[Update and interpretation of 2021 National Comprehensive Cancer Network (NCCN) "Clinical Practice Guidelines for Bone Tumors"]

The incidence of primary malignant bone tumors is low, and clinical cognition is insufficient. The establishment of diagnostic criteria is of great significance for prognosis of tumors. National Comprehensive Cancer Network (NCCN) regularly publishes "Clinical Practice Guidelines for Bone Tumors" to summarize the latest treatment progress of bone tumors. In the latest version of the guidelines released in November 2020, surgery is the main treatment for chondrosarcoma, chordoma, and giant cell tumor of bone, which can be combined with radiotherapy or targeted therapy. Ewing's sarcoma and osteosarcoma are treated by surgery combined with chemotherapy. Immunotherapy can be used to treat high-grade undifferentiated pleomorphic sarcoma. For recurrent tumors, surgery combined with radiotherapy, chemotherapy, and/or targeted therapy can be used for control. The guidelines provide a reference for the standard treatment of bone tumors.

The comparative integrated multi-omics analysis identifies CA2 as a novel target for chordoma

BACKGROUND

Chordoma is a rare mesenchymal malignancy, with a high recurrence rate and unclear tumorigenic mechanism. Genetic alterations, epigenetic regulators, and chromatin spatial organization play crucial roles in the initiation and progression of chordoma. In the current study, we aim to uncover the novel therapeutical targets for chordoma via using integrated multi-omics analysis.

METHODS

The RNA-sequencing (RNA-seq), assay for transposable accessible chromatin by high throughput sequencing (ATAC-seq) and Hi-C were performed between chordoma and human nucleus pulposus (HNP), along with imageological examination and clinical information. The expressions of identified targets were validated by clinical samples and their function were further evaluated by cell and animal experiments via gene knockdown and inhibitors.

RESULTS

The integrated multi-omics analysis revealed the important roles of bone microenvironment in chordoma tumorigenesis. By comparing the hierarchical structures, CA2 and THNSL2 were identified in the switched compartments, cell-specific boundaries and loops. Additionally, CA2 was highly expressed in chordoma, but barely found in HNP. The cell growth and migration of chordoma cells were dramatically suppressed via inhibition of CA2 either with genetic deletion or pharmaceutical treatment with Dorzolamide HCl. Furthermore, Dorzolamide HCl also regulated the bone microenvironment by blocking the osteoclast differentiation of bone marrow monocytes.

CONCLUSION

This study uncovers the roles of bone microenvironment in the chordoma tumorigenesis and identifies CA2 as a novel therapeutic target for chordoma. Besides, our findings suggest Dorzolamide HCl as a promising therapeutic option for chordoma.

Clivus Chordoma: Case Report and Current Considerations on Treatment Strategies

Chordomas are the rare malignant bone lesions derived from the embryonic notochord. They are slow-growing tumors with a locally aggressive behavior. The clival chordomas are extradural, exophytic, and lytic lesions centered on the clivus, and are managed differently from those arising elsewhere because of the emphasis on preserving the neurological function. The gold standard for therapy is the complete resection followed by radiation therapy for a better local control of the tumor. This case report concerns a 20-year old girl with an incidental diagnosis of the clival chordoma, which was first treated via an endoscopic anterior approach to remove the exophytic portion of the tumor. The adjuvant radiation therapy was not feasible because of the macroscopic intradural residual tumor being at the level of jugular foramen. The girl was referred to our institute for the removal of the intradural residual tumor via a petro-occipital trans-sigmoid (POTS) approach followed by adjuvant proton beam therapy. The choice of the surgical approach depends on the size of the tumor, its location, and its anatomical distribution, but should also be balanced against the morbidity, considering the patient's age, and the feasibility of postoperative rehabilitation.

Outcomes of Surgery for Sacral Chordoma and Impact of Complications: A Report of 50 Consecutive Patients With Long-Term Follow-Up

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To determine predictive factors of overall survival (OS) and local recurrence (LR), report complications, and assess the impact of complications on survival, recurrence, and function in patients undergoing en bloc resection of sacral chordoma.

METHODS

This retrospective case series was obtained from a prospective database (1995-2016). All patients underwent en bloc resection of sacral chordoma. Demographic, perioperative, and complication data were collected. Outcomes included: overall survival(OS), local recurrence(LR), and complications. Survival analysis with multivariable cox regression was performed.

RESULTS

Among 50 patients, median follow-up was 5.3 years (range = 1.3-17.2). The majority (82%) underwent a negative margin resection. Survival: 17 patients died (34%) with a median OS of 10.0 years (range = 1.3-17.2). Multivariable cox regression revealed that a negative margin resection was not significantly associated with improved survival (HR = 3.35, 95%CI 0.87-12.80, P = .078). Recurrence: 20 patients (40%) experienced LR with a median time of 6.2 years (range = 0-16.9). Multivariable cox regression revealed that a negative margin resection was associated with a significant decreased risk of LR (HR = 4.96, 95%CI 1.84-13.34, P = 0.002,). A 62% overall complication rate was seen (42% major), with 26% reoperation rate. Of the reoperations, 54% were delayed (>6 weeks after the index surgery). Multivariable cox regression demonstrated that neither major complication nor reoperation significantly impacted OS (HR = 0.62, 95%CI 0.22-1.79, P = 0.380), LR (HR = 1.28, 95%CI 0.49-3.36, P = 0.611), or functional outcomes (OR = 2.94, 95%CI 0.25-34.8, P = 0.393).

CONCLUSIONS

Negative margin resection was associated with decreased LR. Neither major complication nor reoperation significantly impacted OS, LR, or functional outcome. Though additional studies are needed, it appears that despite the morbidity associated with sacral chordoma resection, the long-term clinical outcomes are favorable.

Ciprofloxacin enhances phototoxicity of 5-aminolevulinic acid mediated photodynamic treatment for chordoma cell lines

BACKGROUND

Chordoma are uncommon aggressive tumors of the skeleton. Surgical resection is often subtotal and adjuvant treatment possibilities are limited as chordomas are highly chemo- and radioresistant. In the present study we examined the impact of 5-ALA PDT on different human chordoma cell lines. Furthermore, we investigated the variation of two parameters: (1.) 5-ALA incubation time and (2.) supplemental use of ciprofloxacin as iron chelator.

METHODS

Experiments were realized in vitro with three different human chordoma cell lines: U-CH2, U-CH2B and U-CH14. After pre-incubation for 24 h with various concentrations of ciprofloxacin (1.5 - 5.0 μg/ml), different amounts of 5-ALA (15 - 50 μg/ml) were applied to the cells either for a brief (4 h) or a long (6 h) incubation time. Subsequently cells were exposed to photodynamic radiation. Cell viability was exploited by WST-1 assay. Thus, for each of the three cell lines, two drug combinations (ciprofloxacin plus 5-ALA and 5-ALA only) and two incubation times (short, 4 h and long, 6 h) were tested. Negative control groups were also examined.

RESULTS

Supplemental use of ciprofloxacin led to increased cell death in each of the cell lines. Different 5-ALA incubation times (4 h vs. 6 h) showed no significant differences in cell viability except for U-CH2.

CONCLUSION

Ciprofloxacin as an ordinary applied antibiotic, enhanced the effect of 5-ALA PDT on different human chordoma cell lines in vitro. The impact was dependent on the dose of ciprofloxacin-5-ALA. There were no notable differences for the tested 5-ALA incubation times. In human chordoma cell lines 5-ALA PDT may effectively be amended by ciprofloxacin.

Sellar Tumors

Sellar region lesions include a broad range of benign and malignant neoplastic as well as non-neoplastic entities, many of which are newly described or have recently revised nomenclature. In contrast to other intracranial sites, imaging features are relatively less specific, and the need for histopathological diagnosis is of paramount importance. This review will describe pituitary adenomas, inflammatory lesions, and tumors unique to the region (craniopharyngioma) as well as tumors which may occur in but are not exclusively localized to the sellar location (schwannoma, metastasis, etc.).

Chordoma of the sacrum and mobile spine: a narrative review

Chordoma is a notochord-derived primary tumor of the skull base and vertebral column known to affect 0.08 to 0.5 per 100,000 persons worldwide. Patients commonly present with mechanical, midline pain with or without radicular features secondary to nerve root compression. Management of these lesions has classically revolved around oncologic resection, defined by en bloc resection of the lesion with negative margins as this was found to significantly improve both local control and overall survival. With advancement in radiation modalities, namely the increased availability of focused photon therapy and proton beam radiation, high-dose (>50 Gy) neoadjuvant or adjuvant radiotherapy is also becoming a standard of care. At present chemotherapy does not appear to have a role, but ongoing investigations into the ontogeny and molecular pathophysiology of chordoma promise to identify therapeutic targets that may further alter this paradigm. In this narrative review we describe the epidemiology, histopathology, diagnosis, and treatment of chordoma.

Transformed notochordal cells trigger chronic wounds destabilizing the vertebral column and bone homeostasis

Notochordal cells play a pivotal role in vertebral column patterning, contributing to the formation of the inner architecture of intervertebral discs (IVDs). Their disappearance during development has been associated with reduced repair capacity and IVD degeneration. Notochord cells can give rise to chordomas, a highly invasive bone cancer associated with late diagnosis. Understanding the impact of neoplastic cells during development and on the surrounding vertebral column could open avenues for earlier intervention and therapeutics. We investigated the impact of transformed notochord cells in the zebrafish skeleton using a line expressing RAS in the notochord under the control of the kita promoter, with the advantage of adulthood endurance. Transformed cells caused damage in the notochord and destabilised the sheath layer, triggering a wound repair mechanism, with enrolment of sheath cells (col9a2⁺) and expression of wt1b, similar to induced notochord wounds. Moreover, increased recruitment of neutrophils and macrophages, displaying abnormal behaviour in proximity to the notochord sheath and transformed cells, supported parallels between chordomas, wound and inflammation. Cancerous notochordal cells interfere with differentiation of sheath cells to form chordacentra domains, leading to fusions and vertebral clefts during development. Adults displayed IVD irregularities reminiscent of degeneration, including reduced bone mineral density and increased osteoclast activity, along with disorganised osteoblasts and collagen, indicating impaired bone homeostasis. By depleting inflammatory cells, we abrogated chordoma development and rescued the skeletal features of the vertebral column. Therefore, we showed that transformed notochord cells alter the skeleton during life, causing a wound-like phenotype and activating chronic wound response, suggesting parallels between chordoma, wound, IVD degeneration and inflammation, highlighting inflammation as a promising target for future therapeutics.

This article has an associated First Person interview with the first author of the paper.

Summary: Analyses using a zebrafish line expressing RAS in the notochord, under the control of the kita promoter, revealed that transformed notochord cells alter the skeleton during life, causing a wound-like phenotype and activating chronic wound response.

LncRNA-NONHSAT024778 promote the proliferation and invasion of chordoma cell by regulating miR-1290/Robo1 axis

Chordoma is a malignant bone tumor originating from the embryonic remnants of the notochord. lncRNAs act as competing endogenous RNAs (ceRNAs) and play a critical role in tumor pathology. However, the biological role of lncRNA-NONHSAT024778 and the underlying molecular mechanism in chordoma remains unknown. qRT-PCR was used to analyze the expression changes of NONHSAT024778 and miR-1290 in chordoma tissues and cell lines. Bioinformatics analysis and luciferase reporter assay were applied to detect the targeting binding effect between NONHSAT024778 and miR-1290, and between Robo1 and miR-1290. The effect of NONHSAT024778 on chordoma cell proliferation and invasion and its regulation of miR-1290 by acting as a ceRNA were also investigated. An increased NONHSAT024778 expression was correlated with a decreased miR-1290 level in chordoma tissues. NONHSAT024778 knockdown suppressed the proliferation and invasion of chordoma cells. miR-1290 restored expression rescued the carcinogenic function of NONHSAT024778. Bioinformatics analysis showed that NONHSAT024778 acted as ceRNA to regulate Robo1 via sponging miR-1290 in chordoma cells, thereby promoting chordoma cell malignant progression. In vivo results confirmed the anti-tumor effects of NONHSAT024778 knockdown activating miR-1290 to inhibit the oncogene Robo1. NONHSAT024778 is substantially overexpressed, whereas miR-1290 is decreased in chordoma tissue. NONHSAT024778-miR-1290-Robo1 axis plays a critical role in chordoma tumorigenesis and might be a potential predictive biomarker for the diagnosis and therapeutic target among patients with chordoma.

Sacral and thoracic chordoma with pulmonary metastases: A case report and review of the literature

Chordoma is a sporadic type of cancer that affects the spine and is particularly challenging to treat due to the paucity of reported cases and scientific literature. In particular, primary chordomas affecting both the sacral and thoracic vertebrae are extremely rare. We herein report a rare case of chordoma in the sacral and thoracic vertebrae with pulmonary metastasis, along with a literature review. The objective of the present study was to explore treatment options and long-term outcomes in patients with metastatic chordoma. Posterior decompression was performed for the thoracic tumor, followed by extended resection of the sacral tumor. The symptoms of the patient were relieved after surgery, and the postoperative Nurick score decreased from grade 3 to grade 2, while the postoperative McCormick score was I. Therefore, complete chordoma excision and internal spinal fixation may effectively reduce tumor recurrence and metastasis.

Clivus chordomas: Heterogeneous tumor extension requires adapted surgical approaches

OBJECTIVE

Clivus chordomas are semi-malignant, but infiltratively growing tumors. Currently, a widely-accepted treatment concept encompasses maximal, but safe, surgical resection and radiotherapy. Caused by the size and the tumor extension, different surgical approaches, especially in recurrent cases, might be necessary.

METHODS

Retrospective review of 50 patients on whom 70 surgeries were performed: 29 in primary and 41 in recurrent cases. Based on MRI images, all cases were asserted according to the size and the extension of the tumor. Used surgical approaches were evaluated. Postoperative complications, neurological function prior to and after the surgery, the extent of tumor resection on postoperative MR images were assessed and progression-free survival was calculated.

RESULTS

Tumor size was estimated as small (< 5 cm³) in 8, as medium (5-20 cm³) in 21, as large (20-100 cm³) in 17, and as giant (> 100 cm³) in 4 patients. Most frequently used surgical approaches in primary cases were the transsphenoidal one and midfacial degloving (51.7 % and 17.2 %, respectively). In recurrent cases, dependent on the tumor extension, transsphenoidal (21.9 %), retrosigmoidal (29.3 %), and pterional (19.5 %) approaches, as well as midfacial degloving (17.1 %) were used. Due to the vast tumor extension and infiltration, gross total or near total resection could be achieved in 12 patients (24 %), only. There was no mortality and no major complications in primary cases. In recurrences, however, postoperative hemorrhages and strokes emerged in 4.9 % and 7.1 %. Minor complications occurred in 17.1 % and were dominated by CSF leaks (12.2 %), both in primary in recurrent cases. While most cranial nerve impairments were caused by tumor infiltration of the cavernous sinus, and hence have not improved by treatment, the sixth nerve palsy as a consequence of tumor mass compression, could significantly be improved by surgery. Following surgery, patients were subjected to radiotherapy (68.9 % for primary cases, and 36.6 % for recurrences) mainly with carbon ions. Overall, 5-year progression-free survival was 44.7 %.

CONCLUSION

Caused by the heterogenous pattern of growth of clivus chordomas, surgical approaches should be chosen individually. Vast and infiltrative tumor extension constitute major limitations of surgical resection, and hence result in poor progression-frees survival.