Clinical and histopathologic features of chordomas in children and young adults

Impact of CDK Inhibitors on TBXT Expression in Chordoma Cell Lines Including the First Stable Cell Line of a High-Grade Chordoma

Chordomas are very rare malignant neoplasms of the bone occurring almost exclusively along the spine. As the tumours are thought to arise from notochordal remnants, the vast majority of chordomas express the TBXT gene, resulting in detectable nuclear amounts of its gene product brachyury. This T-Box transcription factor is commonly recognised as being essential in chordoma cells, and limiting TBXT expression is thought to be the key factor in controlling this tumour. Although the tumour is rare, distinct molecular differences and vulnerabilities have been described with regard to its location and the progression status of the disease, rendering it mandatory for novel cell lines to reflect all relevant chordoma subtypes. Here, we describe a novel chordoma cell line arising from the pleural effusion of a disseminated, poorly differentiated chordoma. This cell line, U-CH22, represents a highly aggressive terminal chordoma and, therefore, fills a relevant gap within the panel of available cell culture models for this orphan disease. CDK7 and CDK9 inhibition was lately identified as being effective in reducing viability in four chordoma cell lines, most likely due to a reduction in brachyury levels. In this study, we determined the capability of the CDK7 inhibitor THZ1 and the CDK1/2/5/9 inhibitor dinaciclib to reduce TBXT expression at mRNA and protein levels in a broad range of nine cell lines that are models of primary, recurrent, and metastasised chordoma of the clivus and the sacrum.

The NIH pediatric/young adult chordoma clinic and natural history study: Making advances in a very rare tumor

BACKGROUND

Chordomas are rare tumors arising from the skull base and spine, with approximately 20 pediatric chordoma cases in the Unitedn States per year. The natural history and optimal treatment of pediatric chordomas, especially poorly differentiated and dedifferentiated subtypes, is incompletely understood. Herein, we present findings from our first National Cancer Institute (NCI) chordoma clinic and a retrospective analysis of published cases of pediatric poorly differentiated chordomas (PDC) and dedifferentiated chordomas (DC).

METHODS

Patients less than 40 years old with chordoma were enrolled on the NCI Natural History and Biospecimens Acquisitions Study for Children and Adults with Rare Solid Tumors protocol (NCT03739827). Chordoma experts reviewed patient records, evaluated patients, and provided treatment recommendations. Patient-reported outcomes, biospecimens, and volumetric tumor analyses were collected. A literature review for pediatric PDC and DC was conducted.

RESULTS

Twelve patients (median age: 14 years) attended the clinic, including four patients with active disease and three patients with PDC responsive to systemic therapy. Consensus treatment, management, and recommendations were provided to patients. Literature review returned 45 pediatric cases of PDC or DC with variable treatments and outcomes.

CONCLUSIONS

A multidisciplinary expert clinic was feasible and successful in improving understanding of pediatric chordoma. While multimodal approaches have all been employed, treatment for PDC has been inconsistent and a recommended standardized treatment approach has not been defined. Centralized efforts, inclusive of specialized chordoma-focused clinics, natural history studies, and prospective analyses will help in the standardization of care for this challenging disease.

De novo Versus Secondary Dedifferentiated Chordomas: A Population-Based Analysis and Integrated Individual Participant Data Meta-Analysis

OBJECTIVE

There is a lack of data about the clinicopathological and molecular characteristics of de novo versus secondary dedifferentiated chordoma (DC). This integrated study aimed to investigate the similarities and differences in clinicopathological manifestations, prognoses, and molecular profiles of these 2 subtypes.

METHODS

We accessed the Surveillance, Epidemiology, and End Results (SEER) Program for DC cases from 1975 to 2020. Three electronic databases were also searched for additional DCs. Individual patient data of DC patients from SEER and published literature were combined in integrated analyses.

RESULTS

After excluding duplicated patients, we identified 14 and 116 DC patients from SEER and published literature, respectively. There were 74 de novo, 39 secondary, and 18 cases with unknown origin. Our results showed that de novo and secondary DCs were not statistically different in terms of age, gender, primary location, tumor size, distant metastasis at diagnosis, extent of resection, and chemotherapy receipt. There was limited available molecular data for de novo and secondary DCs, though examples TP53 mutations were found in both. In addition, the rates of tumor relapse, metastasis during follow-up, and patient mortality were also comparable between the 2 groups. In the multivariate Cox regression model, we demonstrated that gross total removal and radiotherapy use were associated with prolonged survival of DCs.

CONCLUSIONS

De novo and secondary DCs were statistically comparable in terms of patient demographics, clinical manifestations, and prognoses. Gross total excision and radiotherapy were optimal treatments associated with better outcomes of DC patients.

High dose image-guided, intensity modulated radiation therapy (IG-IMRT) for chordomas of the sacrum, mobile spine and skull base: preliminary outcomes

PURPOSE

To report preliminary outcomes of high dose image-guided intensity modulated radiotherapy (IG-IMRT) in the treatment of chordomas of the sacrum, mobile spine and skull base.

METHODS

Retrospective analysis of chordoma patients treated with surgery and/or radiotherapy (RT) in a single tertiary cancer center. Initial treatment was categorized as (A) Adjuvant or definitive high-dose RT (78 Gy/39fx or 24 Gy/1fx) vs (B) surgery-only or low dose RT. The primary endpoint was the cumulative incidence of local failure.

RESULTS

A total of 31 patients were treated from 2010 through 2020. Median age was 55 years, tumor location was 64% sacrum, 13% lumbar, 16% cervical and 6% clivus. Median tumor volume was 148 cc (8.3 cm in largest diameter), 42% of patients received curative-intent surgery and 65% received primary RT (adjuvant or definitive). 5-year cumulative incidence of local failure was 48% in group A vs 83% in group B (p = 0.041). Tumor size > 330 cc was associated with local failure (SHR 2.2, 95% CI 1.12 to 7.45; p = 0.028). Eight patients developed distant metastases, with a median metastases-free survival of 56.1 months. 5-year survival for patients that received high dose RT was 72% vs 76% in patients that received no or low dose RT (p = 0.63).

CONCLUSION

Our study suggests high-dose photon IG-IMRT improves local control in the initial management of chordomas. Health systems should promote reference centers with clinical expertise and technical capabilities to improve outcomes for this complex disease.

Management of pediatric clival chordoma with extension to the craniocervical junction and occipito-cervical fusion: illustrative case

BACKGROUND

Chordomas are rare malignant neoplasms that develop from the primitive notochord with < 5% of the tumors occurring in pediatric patients younger than the age of 20. Of these pediatric chordomas, those affecting the craniocervical junction (C1–C2) are even more rare; therefore, parameters for surgical management of these pediatric tumors are not well characterized.

OBSERVATIONS

In this case, a 3-year-old male was found to have a clival chordoma on imaging with extension to the craniocervical junction resulting in spinal cord compression. Endoscopic-assisted transoral transclival approach for clival tumor resection was performed first. As a second stage, the patient underwent a left-sided far lateral craniotomy and cervical laminectomy for resection of the skull base chordoma and instrumented fusion of the occiput to C3. He made excellent improvements in strength and dexterity during rehab and was discharged after 3 weeks.

LESSONS

In pediatric patients with chordoma with extension to the craniocervical junction and spinal cord compression, decompression with additional occipito-cervical fusion appears to offer a good clinical outcome. Fusion performed as a separate surgery before or at the same time as the initial tumor resection surgery may lead to better outcomes.

Characteristics and overall survival in pediatric versus adult skull base chordoma: a population-based study

PURPOSE

Less than 5% of chordomas occur in pediatric patients. While many studies have explored the treatment and outcomes of skull base chordomas, few have focused on the differences between pediatric and adult populations. The aim of this study is to analyze the epidemiological variables and clinical outcomes between pediatric and adult skull base chordomas using a large-sample, population-based cancer database.

METHODS

The National Cancer Database was queried between 2004 and 2015 for skull base chordomas. We stratified patients as pediatric (<18 years) and adults (≥18 years). We compared several clinical covariates between the two groups.

RESULTS

Our cohort consisted of 658 patients, 61 pediatric (9.3%), and 597 adults (90.7%). Pediatric patients were more likely to have larger tumor size (41.4 ± 15.7 mm versus 34.1 ± 15.8 mm, p < 0.01) and universally treated at academic facilities. There was no significant difference in overall survival.

CONCLUSIONS

Pediatric skull base chordomas are rare tumors that are managed with aggressive surgical resection, followed by radiation. While there may be difference between tumor presentation, outcomes between pediatric and adult patients are similar.

Dedifferentiated Chordoma: Clinicopathologic and Molecular Characteristics With Integrative Analysis

Dedifferentiated chordoma is a rare chordoma subtype characterized by a high-grade sarcoma juxtaposed to conventional chordoma. We identified a series of dedifferentiated chordomas, reviewed clinicopathologic features, performed next-generation sequencing in select cases, and analyzed all related English-language publications. Our series included 7 men and 3 women (age 15 to 80 y [median: 54 y]; <1% of >1000 chordomas surveyed). The tumor (2.8 to 24.5 cm [median: 5.8 cm] in size) presented de novo or as recurrence (including postradiotherapy) in sacrum (n=5), skull base (n=2), lumbar spine (n=1), thoracic/mediastinum (n=1), and lung (n=1; as metastasis). Histologically, the dedifferentiated component (3% to 95% [median: 60%]) was pleomorphic-to-fibrosarcomatous, juxtaposed to conventional (n=8) or chondroid (n=2) component. By immunohistochemistry, the conventional/chondroid component consistently expressed cytokeratin and brachyury, whereas the dedifferentiated component showed loss of both. We identified a sacral conventional chordoma with INI1 loss, with one of the lung metastases showing biphasic histology with loss of cytokeratin and brachyury in the dedifferentiated component. Sequencing identified tumor suppressor mutations in 4 tumors, including TP53 mutations in the dedifferentiated component in 3 tumors. Of 7 patients with follow-up, 6 developed metastases; 4 died at 15 to 99 months (median: 24 mo) after dedifferentiated chordoma diagnosis. Collectively, of 87 dedifferentiated chordoma patients described in 1913-2020 (including 10 herein), the median overall survival was 20 months. In summary, dedifferentiated chordoma involves diverse sites and presents de novo, postradiotherapy, or as recurrence/metastasis months-to-years after initial diagnosis. The dedifferentiated component shows loss of brachyury and cytokeratin staining and harbors recurrent TP53 mutations, implicating tumor suppressor dysregulation in chordoma dedifferentiation.

Chemoradiotherapy for Unresectable INI1-negative Chordoma in a Child

The characteristics of chordomas in children are distinct from those in adults. In particular, the prognosis of patients with INI1-negative chordoma is dismal. The standard treatment for localized chordoma, complete surgical resection with a wide margin, is seldom feasible for chordomas arising at the clivus in children, mainly due to associated complications. Therefore, other treatments for unresectable chordomas in children, including chemoradiotherapy, must be explored. Here, we report a 7-year-old girl with an INI1-negative chordoma of the clivus, who responded to conventional chemotherapy plus radiotherapy. Without surgical resection, she remains alive after 1 year and 7 months of the initial diagnosis.

The clincoradiologic spectrum of notochordal derived masses

The notochord is an essential part of human development that regresses with age. Masses derived from notochordal tissue may be encountered during imaging of the neuroaxis. Fortunately, the majority of these are benign and can usually be differentiated by radiological and clinical findings. In this manuscript, we discuss the clinical and radiologic presentation of the four notochordal derived masses and present a brief overview of their management.

Proton therapy for pediatric malignancies: Fact, figures and costs. A joint consensus statement from the pediatric subcommittee of PTCOG, PROS and EPTN

Radiotherapy plays an important role in the management of childhood cancer, with the primary aim of achieving the highest likelihood of cure with the lowest risk of radiation-induced morbidity. Proton therapy (PT) provides an undisputable advantage by reducing the radiation 'bath' dose delivered to non-target structures/volume while optimally covering the tumor with tumoricidal dose. This treatment modality comes, however, with an additional costs compared to conventional radiotherapy that could put substantial financial pressure to the health care systems with societal implications. In this review we assess the data available to the oncology community of PT delivered to children with cancer, discuss on the urgency to develop high-quality data. Additionally, we look at the advantage of combining systemic agents with protons and look at the cost-effectiveness data published so far.

Analysis of variants at LGALS3 single nucleotide polymorphism loci in skull base chordoma

Although LGALS3 has been widely studied, the genotypes of the LGALS3 single nucleotide polymorphism (SNP) loci in skull base chordoma (SBC) have been not well defined. The aim of the current study was to analyze two LGALS3 SNP genotypes in patients with SBC. A total of 48 patients with SBC who underwent surgical treatment in Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University (Beijing, China) and 66 healthy participants were included in the present study. A total of two SNPs (LGALS3+191 C>A and LGALS3 +292 A>C) were selected for sequencing analysis of amplified target fragments from DNA that was extracted from blood samples. The clinical features of the patients were recorded, follow-up was conducted and statistical analysis was performed with SPSS 20.0. There were no differences in age and sex between the patients and control group. In addition, there were no significant differences in the distribution of genotypes (P=0.662) and allelic frequencies (P=0.638) at LGALS3+191 C>A between the two groups. However, significant difference was observed in the allelic distributions at LGALS3 +292 A>C between them (P=0.016), and allele A was associated with the occurrence of SBC. The distribution of the genotypes at LGALS3 +292 A>C was not significantly different in the additive model (CC vs. AC vs. AA, P=0.083) but was significantly different in the dominant model (CC+AC vs. AA, P=0.043). In the Kaplan-Meier analysis, there were no significant differences in the overall survival and progression analysis between different genotypes at LGALS3 +191 C>A (P=0.168 and P=0.120) in patients with SBC. There was no significant difference in overall survival was observed between the genotypes at +292 A>C (P=0.595). However, the progression-free survival (PFS) time of the CC+AC genotype group was longer compared with the AA genotype group (P<0.001). In the univariate and multivariate analysis of tumor progression, PFS was shorter in the AA genotype group compared with the CC+AC genotype group (P<0.001). The allele A and AA genotype at LGALS3 +292 A>C were observed to be associated with a higher risk of SBC, and the AA genotype at +292 A>C was associated with a shorter PFS time.

High sensitivity of FISH analysis in detecting homozygous SMARCB1 deletions in poorly differentiated chordoma: a clinicopathologic and molecular study of nine cases

Poorly differentiated chordomas (PDCs) represent a rare subset of notochordal neoplasms, affecting primarily children and associated with an aggressive outcome. In contrast to conventional chordomas, PDC show solid growth and increased cellularity, cytologic atypia, and mitotic activity. Recent studies have shown that PDCs are characterized by recurrent deletions encompassing the SMARCB1 locus, resulting in consistent loss of nuclear SMARCB1 expression. Thus PDC joined the expanding family of SMARCB1-deficient tumors characterized by various SMARCB1 structural abnormalities, ranging from large homozygous deletions to small intragenic mutations. In the present study, we investigate the SMARCB1 abnormalities in a group of nine well-characterized PDCs and to establish the sensitivity of the FISH method in detecting these changes in the clinical setting. We further assessed the pathologic features and clinical behavior of this cohort managed at our referral center over a 20-year period. The mean age at diagnosis was 10 years-of-age. All except one case occurred in the cranial region. All demonstrated strong nuclear expression of brachyury and loss of SMARCB1 expression. FISH identified homozygous SMARCB1 deletions in all except one case; additionally two cases revealed a heterozygous EWSR1 locus co-deletion. Clinical follow-up information was available in five patients. Two patients presented with distant metastases at initial diagnosis. Two of the three remaining patients with primary disease failed both locally and distantly after multimodality therapy. We conclude that PDCs are highly aggressive tumors and the dominant mechanism of loss of SMARCB1 expression is through large, homozygous SMARCB1 deletions that can be readily detected by FISH.

Downregulation of SMARCB1/INI1 expression in pediatric chordomas correlates with upregulation of miR-671-5p and miR-193a-5p expressions

Loss of SMARCB1/INI1 expression is considered to be a hallmark for childhood chordomas (CCs). Although mutation/loss of 22q has strongly established the loss of SMARCB1/INI1 in cancers, the cause in CCs remains elusive. Recent studies suggest role of miRNAs in regulation of SMARCB1/INI1 expressions. We examined 5 reported/target predicted miRNAs to SMARCB1/INI1 in SMARCB1/INI1 immunonegative and immunopositive cases, and found upregulation of miR-671-5p and miR-193a-5p in SMARCB1/INI1-immunonegative cases. Notably, these two miRNAs were significantly predicted to target TGF-β signaling, suggestive of dysregulation of developmental and osteoblast regulation pathway in CCs. Overall, we suggest miR-671-5p- and miR-193a-5p-mediated epigenetic mode of SMARCB1/INI1 loss and downregulated TGF-β pathway in CCs.

Chordoma Occurs in Young Children With Tuberous Sclerosis

Chordomas are rare bony neoplasms usually unassociated with a familial tumor predisposition syndrome. The peak incidence of this midline axial skeletal tumor is in adulthood but when very young children are affected, consideration should be given to occurrence within the tuberous sclerosis (TS) complex, especially when presenting in neonates <3 months of age. To call attention to this association, we present a brachyury-immunopositive chordoma occurring in the skull base of a 2-month-old male infant who was later realized to have metastases to the subcutaneous tissues and lungs, as well as rhabdomyoma of the heart and renal cysts/angiomyolipomas, that is, characteristic features of the TS complex. We review the limited literature on this topic.

SMARCB1/INI1 Involvement in Pediatric Chordoma: A Mutational and Immunohistochemical Analysis

Chordomas arise in the skull base and spine and usually occur in adults and are rare in the pediatric population. Cases of chordoma in pediatric age are often poorly differentiated, showing cytologic atypia, increased cellularity, and mitosis, and their aggressive behavior is associated with a high incidence of metastatic spread and a short patient survival. Recent studies have described loss of SMARCB1/INI1 protein in poorly differentiated chordomas associated not with point mutations but with SMARCB1/INI1 gene deletions instead. In this study, we considered immunohistochemistry and SMARCB1/INI1 mutational status to examine SMARCB1 status in a series of pediatric chordomas (7 classic and 1 poorly differentiated). We performed immunohistochemical tests for INI1, brachyury, S100, and cytokeratins and conducted a genetic analysis on the SMARCB1 coding sequence (NM_003073) using the Sanger method and multiplex ligation-dependent probe amplification to detect abnormal copy numbers of the gene locus. All 8 cases were positive for brachyury, whereas there was no nuclear SMARCB1/INI1 expression in 4 of the 8 cases, including the poorly differentiated chordoma. Genetic analysis identified a missense mutation in 2 cases and a nonsense mutation associated with loss of SMARCB1/INI1 protein and features of poorly differentiated tumor in 1. These mutations were novel variants occurring in heterozygosity, and they were judged to be pathogenic by 3 different bioinformatic tools. In 7 of 8 cases we performed multiplex ligation-dependent probe amplification, and 3 cases showed deletions at the SMARCB1 locus. Our results confirm the pathogenic involvement of SMARCB1/INI1 in childhood chordoma. We also describe 3 novel pathogenic mutations.

Surgical Consideration for Adolescents and Young Adults With Cervical Chordoma

STUDY DESIGN

Retrospective study.

OBJECTIVE

The aim of this study was to compare the clinical outcomes between adolescent and young adult (AYA) patients and old adult patients with cervical chordoma who were treated surgically and present the surgical consideration for adolescents and young adults with cervical chordoma.

SUMMARY OF BACKGROUND DATA

With predominance in senior patients, chordoma is distinctively rare in AYAs. Because of the rarity of AYA chordoma, individual case report represents most of the literature on this disease entity on mobile spine and lack of long-term follow up, which leads to the paucity of clinical evidence for treatment planning and prognosis prediction.

METHODS

A retrospective study was conducted to investigate the prognosis of AYA patients with cervical chordoma who were treated surgically. We collected the clinical data of these patients and their older counterparts, and further compared the prognosis of the patients in different age groups. To estimate survival curves, Kaplan-Meier method was used, and significance was assessed using a log-rank test.

RESULTS

Forty consecutive patients with chordoma of the cervical spine treated in our institution were included in the study. Two groups were identified according to age. Group 1 comprised children and adolescents (age ≤ 25 yrs; n = 9) and Group 2 comprised adults (age > 25 years; n = 31). In comparison, Group 1 was featured by significantly higher rate of recurrence and shorter overall survival, although no difference found in the surgical modality between two groups.

CONCLUSION

There is a dismal prognosis in young patients with chordoma, and thus support the notion that as radical a total en bloc spondylectomy (TES) of the lesions as possible may benefit the overall survival of these young patients. Although the ensuing neurological deficits may be devastating, it will be worth sacrificing if the life expectancy of these young patients is prolonged.

LEVELS OF EVIDENCE

4.

Metastatic clival chordoma: a case report of multiple extraneural metastases following resection and proton beam radiotherapy in a 5-year old boy

The authors report the case of a 5-year-old boy in whom extraneural metastases developed 5 years after he underwent an occipitocervical fusion and transoral approach to treat a clival chordoma without local recurrence. Following primary resection, the patient's postoperative course was complicated by recurrent meningitis secondary to CSF leak, which responded to antibiotics, and communicating hydrocephalus, for which a ventriculoperitoneal shunt was placed. The patient then underwent postoperative proton beam radiotherapy. Five years following his initial presentation, surveillance imaging revealed a new asymptomatic lung mass for which the patient underwent thoracotomy and resection of the mass. Histological examination of the lung mass revealed findings consistent with a de-differentiated chordoma, confirming extraneural metastasis from the original tumor without evidence of local recurrence. Chest wall and scalp metastases subsequently developed, and the patient was started on an adjuvant chemotherapy regimen that included imatinib and rapamycin followed by subsequent nivolumab and an EZH2 inhibitor for recurrent, disseminated disease. Despite this patient's remote and distant metastases, primary gross-total resection for chordoma remains a critical treatment objective, followed by proton beam radiotherapy. This case illustrates the importance of interval posttreatment imaging and the emerging potential to treat chordoma with molecularly targeted therapies.

Multicentric Chordoma in a Child

Chordomas are primary malignant bone tumors that arise in the axial skeleton, believed to originate from remnants of embryologic notochordal cell rests. Multicentric origin of chordoma is extremely rare. To our literature search, we found only three cases of multicentric chordoma in adults. We report a first case of multicentric chordoma in pediatric age group. A 14-month-old child presented with torticolis and left upper limb monoparesis, imaging showed expansile bony destructive lesion in clivus and dorsal spine simultaneously. The child underwent laminectomy, decompression of cord, excision of lesion, and histopathology was suggestive of chordoma. Pediatric chordomas are aggressive tumors, require multidisciplinary management with maximal safe resection followed by radiotherapy (conventional and/or proton). Even with multidisciplinary management, pediatric chordomas have high morbidity and mortality.

Reprint of "Chordoma in children: Case-report and review of literature"

We report an exceptional case of a very late local failure in a 9-year-old boy presenting with a chordoma of the cranio-cervical junction. The child was initially treated with a combination of surgical resection followed by high dose photon-proton radiation therapy. This aggressive therapy allowed a 9-year remission with minimal side-effects. Unfortunately, he subsequently presented with a local failure managed with a second full-dose course of protons. The child died one year later from local bleeding of unclear etiology.

Secondary EWSR1 gene abnormalities in SMARCB1-deficient tumors with 22q11-12 regional deletions: Potential pitfalls in interpreting EWSR1 FISH results

SMARCB1 inactivation occurs in a variety of tumors, being caused by various genetic mechanisms. Since SMARCB1 and EWSR1 genes are located close to each other on chromosome 22, larger SMARCB1 deletions may encompass the EWSR1 locus. Herein, we report four cases with SMARCB1-deletions showing concurrent EWSR1 gene abnormalities by FISH, which lead initially to misinterpretations as EWSR1-rearranged tumors. Our study group included various morphologies: a poorly differentiated chordoma, an extrarenal rhabdoid tumor, a myoepithelial carcinoma, and a proximal-type epithelioid sarcoma. All cases showed loss of SMARCB1 (INI1) by immunohistochemistry (IHC) and displayed characteristic histologic features for the diagnoses. The SMARCB1 FISH revealed homozygous or heterozygous deletions in three and one case, respectively. The co-hybridized EWSR1 probes demonstrated either unbalanced split signals or heterozygous deletion in two cases each. The former suggested bona fide rearrangement, while the latter resembled an unbalanced translocation. However, all the FISH patterns were quite complex and distinct from the simple and uniform split signals seen in typical EWSR1 rearrangements. We conclude that in the context of 22q11-12 regional alterations present in SMARCB1-deleted tumors, simultaneous EWSR1 involvement may be misinterpreted as equivalent to EWSR1 rearrangement. A detailed clinicopathologic correlation and supplementing the EWSR1 FISH assay with complementary methodology is mandatory for correct diagnosis. © 2016 Wiley Periodicals, Inc.

Fifty-four-month survival in a 3-year-old child presenting with an aggressive metastatic dedifferentiated clival chordoma

Dedifferentiated chordoma is a rare, aggressive, chemoresistant and radioresistant malignancy arising from notochord remnants that can occur anywhere along the spine. Incidence in patients under 20 years of age is 1 per 250 million. We report a case of dedifferentiated clival chordoma presenting in a 3-year-old boy with pulmonary metastasis, which responded unusually well to chemotherapy, achieving complete metastatic clearance and debulking of the primary tumour. Proton beam therapy achieved further tumour control, with excellent quality of life for multiple years. On disease relapse, an atypical lateral transcondylar surgical approach achieved complete macroscopic clearance but there was cutaneous seeding. This, and continued primary site activity, failed to be controlled with targeted therapy, traditional chemotherapy and photon radiation, resulting in gradual neurological decline and death. Intensive management resulted in above-average survival despite diagnosis late in the disease course, which may be of value directing investigation into optimal management.

Chordoma in children: Case-report and review of literature

We report an exceptional case of a very late local failure in a 9-year-old boy presenting with a chordoma of the cranio-cervical junction. The child was initially treated with a combination of surgical resection followed by high dose photon-proton radiation therapy. This aggressive therapy allowed a 9-year remission with minimal side-effects. Unfortunately, he subsequently presented with a local failure managed with a second full-dose course of protons. The child died one year later from local bleeding of unclear etiology.

Paediatric Chordomas

Paediatric chordomas are rare malignant tumours arising from primitive notochordal remnants with a high rate of recurrence. Only 5 % of them occur in the first two decades such less than 300 paediatric cases have been reported so far in the literature. In children, the average age at diagnosis is 10 years with a male-to-female ratio closed to 1. On the opposite to adults, the majority of paediatric chordomas are intracranial, characteristically centered on the sphenooccipital synchondrosis. Metastatic spread seems to be the prerogative of the under 5-year-old children with more frequent sacro-coccygeal locations and undifferentiated histology. The clinical presentation depends entirely on the tumour location. The most common presenting symptoms are diplopia and signs of raised intracranial pressure. Sacrococcygeal forms may present with an ulcerated subcutaneous mass, radicular pain, bladder and bowel dysfunctions. Diagnosis is suspected on computerised tomography showing the bone destruction and with typically lobulated appearance, hyperintense on T2-weighted magnetic resonance imaging. Today, treatment relies on as complete surgical resection as possible (rarely achieved because of frequent invasiveness of functional structures) followed by adjuvant radiotherapy by proton therapy. The role of chemotherapy has not been proven. Prognosis is better than in adults and depends on the extent of surgical resection, age and histology subgroup. Biological markers are still lacking to improve prognosis by developing targeted therapy.

Enigmatic entity in childhood: clival chordoma from a tertiary center's perspective

PURPOSE

Chordoma is a rare neoplasm that arises from embryonic notochordal remnants along the axial skeleton (i.e., clivus, sacrum) and the vertebral bodies. They comprise less than 1 % of CNS tumors and 1-4 % of all bone malignancies. It rarely affects children and adolescents (<5 %). Chordomas are locally aggressive and highly recurrent. Their management is challenging for clinicians.

METHODS

This retrospective study includes six pediatric patients with pathological evidence of clival chordoma. These cases were identified over a period of 15 years in a tertiary care institute.

RESULTS

There were two boy and four girls with a mean age of 10.6 years (range, 4-16 years). The chief complaint was due to cranial nerve palsy (or dysfunction), mostly affecting lower cranial nerves (66.6 %), followed by diplopia and headache. One patient had obstructive sleep apnea. All patients were operated and a total of 15 surgeries were performed (mean, 2.5). Tumor recurrence was observed in four patients (67 %). Two-year and 5-year progression-free survivals (PFS) were 67 and 33 %, respectively. None of the patients were lost either during the surgery or the follow-up period (6.9 years: 1-14 years).

CONCLUSIONS

Clival chordomas are challenging tumors in neurosurgical practice. A multidisciplinary approach is warranted in each patient. Today, the best management strategy seems to be surgical resection followed by radiotherapy. Chemotherapy should be considered in selective and preference basis. Sharing institutional experiences will provide future insights in prognosis of these rare tumors. Implementing newer surgical instruments, endoscope in particular, is encouraged in management of the clival chordomas.

[Chordoma]

PURPOSES

To review in the literature, all the epidemiological, clinical, radiological, histological and therapeutic data regarding chordomas as well as various notochordal entities: ecchordosis physaliphora, intradural and intraparenchymatous chordomas, benign notochordal cell tumors, parachordomas and extra-axial chordomas. To identify different types of chordomas, including familial forms, associations with tuberous sclerosis, Ollier's disease and Maffucci's syndrome, forms with metastasis and seeding. To assess the recent data regarding molecular biology and progress in targeted therapy. To compare the different types of radiotherapy, especially protontherapy and their therapeutic effects. To review the largest series of chordomas in their different localizations (skull base, sacrum and mobile spine) from the literature.

MATERIALS

The series of 136 chordomas treated and followed up over 20 years (1972-2012) in the department of neurosurgery at Lariboisière hospital is reviewed. It includes: 58 chordomas of the skull base, 47 of the craniocervical junction, 23 of the cervical spine and 8 from the lombosacral region. Similarly, 31 chordomas in children (less than 18 years of age), observed in the departments of neurosurgery of les Enfants-Malades and Lariboisière hospitals, are presented. They were observed between 1976 and 2010 and were located intracranially (n=22 including 13 with cervical extension), 4 at the craniocervical junction level and 5 in the cervical spine.

METHODS

In the entire Lariboisière series and in the different groups of localization, different parameters were analyzed: the delay of diagnosis, of follow-up, of occurrence of metastasis, recurrence and death, the number of primary patients and patients referred to us after progression or recurrence and the number of deaths, recurrences and metastases. The influence of the quality of resection (total, subtotal and partial) on the prognosis is also presented. Kaplan-Meier actuarial curves of overall survival and disease free survival were performed in the entire series, including the different groups of localization based on the following 4 parameters: age, primary and secondary patients, quality of resection and protontherapy. In the pediatric series, a similar analysis was carried-out but was limited by the small number of patients in the subgroups.

RESULTS

In the Lariboisière series, the mean delay of diagnosis is 10 months and the mean follow-up is 80 months in each group. The delay before recurrence, metastasis and death is always better for the skull base chordomas and worse for those of the craniocervical junction, which have similar results to those of the cervical spine. Similar figures were observed as regards the number of deaths, metastases and recurrences. Quality of resection is the major factor of prognosis with 20.5 % of deaths and 28 % of recurrences after total resection as compared to 52.5 % and 47.5 % after subtotal resection. This is still more obvious in the group of skull base chordomas. Adding protontherapy to a total resection can still improve the results but there is no change after subtotal resection. The actuarial curve of overall survival shows a clear cut in the slope with some chordomas having a fast evolution towards recurrence and death in less than 4 years and others having a long survival of sometimes more than 20 years. Also, age has no influence on the prognosis. In primary patients, disease free survival is better than in secondary patients but not in overall survival. Protontherapy only improves the overall survival in the entire series and in the skull base group. Total resection improves both the overall and disease free survival in each group. Finally, the adjunct of protontherapy after total resection is clearly demonstrated. In the pediatric series, the median follow-up is 5.7 years. Overall survival and disease free survival are respectively 63 % and 54.3 %. Factors of prognosis are the histological type (atypical forms), localization (worse for the cervical spine and better for the clivus) and again it will depend on the quality of resection.

CONCLUSIONS

Many different pathologies derived from the notochord can be observed: some are remnants, some may be precursors of chordomas and some have similar features but are probably not genuine chordomas. To-day, immuno-histological studies should permit to differentiate them from real chordomas. Improving knowledge of molecular biology raises hopes for complementary treatments but to date the quality of surgical resection is still the main factor of prognosis. Complementary protontherapy seems useful, especially in skull base chordomas, which have better overall results than those of the craniocervical junction and of the cervical spine. However, we are still lacking an intrinsic marker of evolution to differentiate the slow growing chordomas with an indolent evolution from aggressive types leading rapidly to recurrence and death on which more aggressive treatments should be applied.

Prognostic value of MIB-1, p53, epidermal growth factor receptor, and INI1 in childhood chordomas

BACKGROUND

Chordomas are slow-growing tumors and most commonly involve the sacrum and clivus. Multiple recurrences are frequent. Childhood chordomas are rare and often show exceptionally aggressive behavior, resulting in short survival and a high incidence of metastatic spread.

OBJECTIVE

This study examined the histologic features and immunohistochemical profile of pediatric chordomas and compared them with their adult counterparts.

METHODS

Nine pediatric and 13 adult cases were included in the study. Childhood chordomas were classified into conventional, atypical, and poorly differentiated types. Immunohistochemistry was performed for cytokeratin, epithelial membrane antigen, vimentin, S100, brachyury, p53, INI1, epidermal growth factor receptor (EGFR), and CD117. Cytogenetic analyses were performed in a subset of tumors for SMARCB1/INI1 locus on 22q chromosome by fluorescent in situ hybridization (FISH) and analysis of the SMARCB1/INI1 gene sequence.

RESULTS

All tumors showed expression of cytokeratin, epithelial membrane antigen, S100, vimentin, brachyury, and EGFR. Atypical morphology, p53 expression, higher MIB-1 labelling index (LI), and INI1 loss were more frequently seen in pediatric chordomas as compared with adults. None of the tumors showed CD117 expression. No point mutation in the SMARCB1/INI1 gene was noted in the tumors examined; however, 4 pediatric and 1 adult chordoma showed loss of this locus on FISH analysis.

CONCLUSIONS

A subset of pediatric chordomas with atypical histomorphologic features needs to be identified, as they behave in an aggressive manner and require adjuvant therapy. Pediatric chordomas more frequently show p53 expression, INI1 loss, and higher MIB-1 LI as compared with adults, whereas EGFR expression is common to both.

Chondroid chordoma in an atypical location

Chondroid chordoma is an extremely rare tumour with an annual incidence of around 0.1 cases per 100,000population. Involvement of the thoracic vertebrae may be present in 2-5% of cases. Definitive diagnosis usually requires a suitable distinction between this and other mesenchymal tumours such as chondrosarcomas, so immunohistochemical analysis is virtually mandatory. In spite of its slow-growing nature, chondroid chordoma tends to relapse, and it may eventually become malignant, often jeopardising the patient's prognosis. Although surgery remains the main therapeutic approach, research into the molecular and genetic aspects of this tumour is ongoing. These new advances are likely to improve future oncology therapies by complementing surgery and radiotherapy, changing the currently poor prognosis. We report the case of a patient with a chondroid chordoma involving the thoracic vertebrae and pleural cavity, and the treatment performed.

From notochord formation to hereditary chordoma: the many roles of Brachyury

Chordoma is a rare, but often malignant, bone cancer that preferentially affects the axial skeleton and the skull base. These tumors are both sporadic and hereditary and appear to occur more frequently after the fourth decade of life; however, modern technologies have increased the detection of pediatric chordomas. Chordomas originate from remnants of the notochord, the main embryonic axial structure that precedes the backbone, and share with notochord cells both histological features and the expression of characteristic genes. One such gene is Brachyury, which encodes for a sequence-specific transcription factor. Known for decades as a main regulator of notochord formation, Brachyury has recently gained interest as a biomarker and causative agent of chordoma, and therefore as a promising therapeutic target. Here, we review the main characteristics of chordoma, the molecular markers, and the clinical approaches currently available for the early detection and possible treatment of this cancer. In particular, we report on the current knowledge of the role of Brachyury and of its possible mechanisms of action in both notochord formation and chordoma etiogenesis.

Primary chordomas of the cervical spine: a consecutive series of 14 surgically managed cases

OBJECT

Cervical chordomas are rare lesions and usually bring about challenges in treatment planning because of their wide extension and complicated adjacent anatomy. There are few large published series at present focusing on cervical chordomas. The authors studied a consecutive series of 14 patients with primary cervical chordomas who underwent surgical treatment and were observed between 1989 and 2008. By reviewing the clinical patterns and follow-up data, they sought to investigate the clinical characters, tailor the appropriate surgical techniques, and establish prognosis factors for cervical chordomas.

METHODS

Hospitalization and follow-up data in the 14 patients were collected. All patients underwent piecemeal tumor excision and reconstruction for stability; total spondylectomy was achieved in 5 cases. Postoperative radiotherapy was administered in all patients. Kaplan-Meier plots were used to represent tumor recurrence and patient survival, and log-rank testing was used to determine the risk factors of local recurrence.

RESULTS

Follow-up ranged from 8 to 120 months (mean 58.6 months). Symptom and neural status in most patients improved after surgery. The 1- and 5-year disease-free survival rates were 78.6% and 50%, respectively, and the 1- and 5-year survival rates were 92.9% and 85.7%, respectively. Log-rank tests revealed that the following variables were significantly associated with a high rate of tumor recurrence: age less than 40 years or greater than 70 years (p = 0.006) and an upper cervical tumor location (p = 0.019).

CONCLUSIONS

Chordomas in the cervical spine are usually neoplasms that exhibit insidious growth and a wide extension by the time of diagnosis. Radical intralesional debulking surgery and postoperative radiotherapy have been effective treatment. A limited application of en bloc tumor resection and the highly likely intraoperative intralesional tumor seeding may partially explain the high local recurrence rate, whereas the chance of distant metastases, fortunately, is very low. Most recurrence were documented within 3 years. Some specific surgical techniques should be emphasized to minimize tumor seeding. Patients with upper cervical chordomas, younger adults, and elderly adults have worse prognosis. For patients with chordoma extending to both the anterior and posterior spinal columns, total spondylectomy combined with piecemeal excision is recommended for a better prognosis.

Extraskeletal cartilaginous, osseous, and chordoid tumors in children and adolescents

Extraskeletal cartilaginous, osseous, and chordoid tumors are extraordinarily rare in children and adolescents. These lesions are diagnostically challenging due to their rarity and their overlap with metastatic osteosarcoma, reactive or metabolic calcifying and bone-forming masses, various pseudosarcomatous proliferations such as myositis ossificans, and other rare genetic or metabolic disorders. This article reviews the clinicopathologic features and differential diagnosis of extraskeletal cartilaginous, osseous, and chordoid neoplasms in the first two decades of life and highlights the use of diagnostic adjuncts.

Clinical features distinguish childhood chordoma associated with tuberous sclerosis complex (TSC) from chordoma in the general paediatric population

BACKGROUND

Chordoma, an age-dependent rare cancer, arises from notochordal remnants. Fewer than 5% of chordomas occur in children. Tuberous sclerosis complex (TSC) is an autosomal dominant neurocutaneous syndrome characterised by abnormal tissue growths in multiple organ systems. Reports of chordoma in children with TSC suggest that TSC1 and TSC2 mutations may contribute to chordoma aetiology.

METHODS

To determine whether the 10 TSC-associated childhood chordomas reported in the literature are representative of chordoma in the general paediatric population, the authors compared age at diagnosis, primary site and outcome in them with results from a systematic assessment of 65 paediatric chordoma cases reported to the US population-based cancer registries contributing to the SEER Program of the National Cancer Institute.

RESULTS

TSC-associated paediatric chordomas differed from chordomas in the general paediatric population: median age at diagnosis (6.2 months, TSC, vs 12.5 years, SEER); anatomical site (40% sacral, TSC, vs 9.4% sacral, SEER); and site-specific age at diagnosis (all four sacral chordomas diagnosed during the fetal or neonatal period, TSC, vs all six sacral chordomas diagnosed at >15 years, SEER). Finally, three of four patients with TSC-associated sacral chordoma were alive and tumour-free at 2.2, 8 and 19 years after diagnosis versus a median survival of 36 months among paediatric patients with sacral chordoma in SEER.

CONCLUSIONS

These results strengthen the association between paediatric chordoma and TSC. Future clinical and molecular studies documenting the magnitude and clinical spectrum of the joint occurrence of these two diseases should provide the basis for delineating the biological relationship between them.

Loss of SMARCB1/INI1 expression in poorly differentiated chordomas

Chordomas are malignant neoplasms that typically arise in the axial spine and primarily affect adults. When chordomas arise in pediatric patients they are more likely to display unusual histological features and aggressive behavior. We noted the absence of SMARCB1/INI1 expression by immunohistochemistry in an index case of poorly differentiated chordoma of the sacrum, leading us to further examine SMARCB1/INI1 expression as well as that of brachyury, a highly specific marker of notochordal differentiation, in 3 additional poorly differentiated chordomas of the clivus, 10 typical chordomas, and 8 atypical teratoid/rhabdoid tumors (AT/RTs). All 4 poorly differentiated chordomas and all AT/RTs lacked nuclear expression of SMARCB1/INI1, while the 10 typical chordomas maintained strong nuclear SMARCB1/INI1 immunoreactivity. All 10 typical and 4 poorly differentiated chordomas expressed brachyury; all 8 AT/RTs were brachyury immunonegative. Cytogenetic evaluation utilizing FISH probes near the SMARCB1/INI1 locus on chromosome 22q was also performed in all of the poorly differentiated chordomas in this series. Three of the four poorly differentiated chordomas had evidence for deletion of this region by FISH. Analysis of the SMARCB1/INI1 gene sequence was performed using formalin-fixed paraffin-embedded tissue in all cases and no point mutations were observed. In summary, all poorly differentiated chordomas in this series showed the absence of SMARCB1/INI1 expression, and were reliably distinguished from AT/RTs, clinically by their characteristic primary sites of origin and pathologically by strong nuclear brachyury expression. Our findings reveal a likely role for SMARCB1/INI1 in a subset of chordomas with aggressive features.

The role of chemotherapy in pediatric clival chordomas

The purpose of this retrospective study was to review the role of chemotherapy in the treatment, management and outcome of children diagnosed with clival chordomas. The medical records of six pediatric chordoma patients diagnosed at Childrens Hospital Los Angeles between 1995 and 2005 were reviewed. Of the six patients reviewed, all underwent an initial surgical resection. Following resection, three received a combination of chemotherapy and radiation therapy, two received chemotherapy alone and one patient refused both forms of therapy; this patient expired of progressive tumor. One patient developed acute monoblastic leukemia (M5a subtype) and died of intracranial hemorrhage during induction chemotherapy, 39 months after initial diagnosis. MRI of brain and spine showed disease progression shortly before his death. Two patients who received chemotherapy only after surgery, one patient who received chemotherapy at relapse following irradiation and one patient who received irradiation followed by chemotherapy are alive with stable radiographic abnormalities at a median follow-up of 9 years from diagnosis (range: 6-13 years). Chemotherapeutic agents included ifosfamide and etoposide in all four surviving patients. Chemotherapy with ifosfamide and etoposide may have a role in the treatment of pediatric clival chordomas when used alone or in combination with irradiation.

Sphenoid masses in children: radiologic differential diagnosis with pathologic correlation

Childhood central skull base masses are rare, often difficult to diagnose, and have overlapping imaging findings. In this review, we provide an overview of the epidemiology, clinical findings, and management of pediatric sphenoid bone and sphenoid sinus masses with an emphasis on imaging findings that may help to differentiate lesions. Radiologic-pathologic correlation is provided. Finally, an imaging-based algorithm is presented as a guide to help radiologists narrow their differential diagnoses. Some of the entities discussed are virtually unique to the pediatric population; others occur rarely in this age group but should be considered in the appropriate clinical setting. Entities included in the discussion are grouped into 2 categories: those that cause nonaggressive osseous remodeling and those that are more commonly associated with aggressive bone changes. Mucocele, aneurysmal bone cyst, giant cell lesions, meningioma, and fibrous dysplasia tend to remodel bone, while entities such as chordoma, craniopharyngioma, rhabdomyosarcoma, sinonasal carcinoma, and neuroblastoma may cause more aggressive local bone changes.