Novel targeted therapies in chordoma: an update

Integrated Molecular and Histological Insights for Targeted Therapies in Mesenchymal Sinonasal Tract Tumors

PURPOSE OF REVIEW

This review aims to provide a comprehensive overview of mesenchymal sinonasal tract tumors (STTs), a distinct subset of STTs. Despite their rarity, mesenchymal STTs represent a unique clinical challenge, characterized by their rarity, often slow progression, and frequently subtle or overlooked symptoms. The complex anatomy of the sinonasal area, which includes critical structures such as the orbit, brain, and cranial nerves, further complicates surgical treatment options. This underscores an urgent need for more advanced and specialized therapeutic approaches.

RECENT FINDINGS

Advancements in molecular diagnostics, particularly in next-generation sequencing, have significantly enhanced our understanding of STTs. Consequently, the World Health Organization has updated its tumor classification to better reflect the distinct histological and molecular profiles of these tumors, as well as to categorize mesenchymal STTs with greater accuracy. The growing understanding of the molecular characteristics of mesenchymal STTs opens new possibilities for targeted therapeutic interventions, marking a significant shift in treatment paradigms. This review article concentrates on mesenchymal STTs, specifically addressing sinonasal tract angiofibroma, sinonasal glomangiopericytoma, biphenotypic sinonasal sarcoma, and skull base chordoma. These entities are marked by unique histopathological and molecular features, which challenge conventional treatment approaches and simultaneously open avenues for novel targeted therapies. Our discussion is geared towards delineating the molecular underpinnings of mesenchymal STTs, with the objective of enhancing therapeutic strategies and addressing the existing shortcomings in the management of these intricate tumors.

Skull Base Tumors

OBJECTIVE

This article reviews the presenting features, molecular characteristics, diagnosis, and management of selected skull base tumors, including meningiomas, vestibular schwannomas, pituitary neuroendocrine tumors, craniopharyngiomas, chordomas, ecchordosis physaliphora, chondrosarcomas, esthesioneuroblastomas, and paragangliomas.

LATEST DEVELOPMENTS

Skull base tumors pose a management challenge given their complex location and, as a result, the tumors and treatment can result in significant morbidity. In most cases, surgery, radiation therapy, or both yield high rates of disease control, but the use of these therapies may be limited by the surgical accessibility of these tumors and their proximity to critical structures. The World Health Organization classification of pituitary neuroendocrine tumors was updated in 2022. Scientific advances have led to an enhanced understanding of the genetic drivers of many types of skull base tumors and have revealed several potentially targetable genetic alterations. This information is being leveraged in the design of ongoing clinical trials, with the hope of rendering these challenging tumors treatable through less invasive and morbid measures.

ESSENTIAL POINTS

Tumors involving the skull base are heterogeneous and may arise from bony structures, cranial nerves, the meninges, the sinonasal tract, the pituitary gland, or embryonic tissues. Treatment often requires a multidisciplinary approach, with participation from radiation oncologists, medical oncologists, neuro-oncologists, and surgical specialists, including neurosurgeons, otolaryngologists, and head and neck surgeons. Treatment has largely centered around surgical resection, when feasible, and the use of first-line or salvage radiation therapy, with chemotherapy, targeted therapy, or both considered in selected settings. Our growing understanding of the molecular drivers of these diseases may facilitate future expansion of pharmacologic options to treat skull base tumors.

Cardiac self-limiting rhabdomyomas in a neonatal patient with tuberous sclerosis complex: a case report with negative genetic testing

Background

Tuberous Sclerosis Complex (TSC) is a hereditary condition that leads to the development of non-malignant neoplasms in various organs, including cardiac rhabdomyomas, which can cause significant complications.

Case presentation

This report describes the case of a 15-day-old male neonate who was hospitalized due to intracardiac masses and brain lesions, despite the absence of TSC gene mutations. The patient's mother exhibited facial angiofibromas, a common feature of TSC. Over a 2-year follow-up period, spontaneous regression of the cardiac tumor was observed.

Conclusions

This case illustrates that not all TSC cases exhibit detectable TSC gene mutations. Current treatment strategies, such as mTOR inhibitors, offer potential effectiveness in managing associated cardiac rhabdomyomas. Further research should focus on evaluating the therapeutic potential of these inhibitors.

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.

Chordoma: 18F-FDG PET/CT and MRI imaging features

OBJECTIVE

Examine the ¹⁸F-FDG PET/CT and MRI imaging characteristics of chordoma.

MATERIALS AND METHODS

Biopsy-proven chordoma with a pre-therapy ¹⁸F-FDG PET/CT from 2001 through 2019 in patients > 18 years old were retrospectively reviewed. Multiple PET/CT and MRI imaging parameters were assessed.

RESULTS

A total of 23 chordoma patients were included (16 M, 7 F; average age of 60.1 ± 13.0 years) with comparative MRI available in 22 cases. This included 13 sacrococcygeal, 9 mobile spine, and one clival lesions. On ¹⁸F-FDG PET/CT, chordomas demonstrated an average SUVmax of 5.8 ± 3.7, average metabolic tumor volume (MTV) of 160.2 ± 263.8 cm³, and average total lesion glycolysis (TLG) of 542.6 ± 1210 g. All demonstrated heterogeneous FDG activity. On MRI, chordomas were predominantly T2 hyperintense (22/22) and T1 isointense (18/22), contained small foci of T1 hyperintensity (17/22), and demonstrated heterogeneous enhancement (14/20). There were no statistically significant associations found between ¹⁸F-FDG PET/CT and MRI imaging features. There was no relationship of SUVmax (p = 0.53), MTV (p = 0.47), TLG (p = 0.48), maximal dimension (p = 0.92), or volume (p = 0.45) to the development of recurrent or metastatic disease which occurred in 6/22 patients over a mean follow-up duration of 4.1 ± 2.0 years.

CONCLUSION

On ¹⁸F-FDG PET/CT imaging, chordomas demonstrate moderate, heterogeneous FDG uptake. Predominant T2 hyperintensity and small foci of internal increased T1 signal are common on MRI. The inherent FDG avidity of chordomas suggests that ¹⁸F-FDG PET/CT may be a useful modality for staging, evaluating treatment response, and assessing for recurrent or metastatic disease.

Biological Treatments of Neurofibromatosis Type 2 and Other Skull Base Disorders

Studies of genomic alterations that occur in skull base tumors have provided information regarding biological aberrations that are necessary for the growth and maintenance of these tumors. This has led to the development and initiation of clinical trials incorporating biological treatments for many skull base tumors. The exciting developments of molecularly targeted therapy for the treatment of skull base tumors may provide noninvasive therapeutic options for patients that can be used either alone or in combination with surgery and/or radiation therapy. Future analysis and continued scientific discovery of treatments for skull base tumors can lead to improved outcomes in patients.

Apparent diffusion coefficient as a prognostic factor in clival chordoma

Clival chordoma is a rare disease with high recurrence rates even after a combination of surgical resection and radiotherapy. Apparent diffusion coefficient (ADC) has been used to evaluate aggressive features of chordoma, but its utility for clival chordoma has not been explored specifically. In this study, the utility of preoperative ADC values was analyzed for predicting tumor progression and recurrence in patients with clival chordoma. Between 2012 and 2019, a total of 30 operated cases were analyzed with available preoperative ADC data. Receiver operating characteristic (ROC) analysis was used to obtain ADC cutoff values for predicting tumor aggressiveness. The mean and minimum ADC values were significantly lower in the aggressive tumor group than in the stable tumor group (both P < 0.001). ROC analysis showed that a mean cutoff ADC value of 1198 × 10⁻⁶ mm²/s and minimum ADC value of 895.5 × 10^–6 mm²/s could be used to predict aggressive features of clival chordoma. Subtotal resection, partial resection, and mean and minimum ADC values that were lower than cutoff values were negative predictors of overall survival and progression-free survival. In conclusion, mean and minimum ADC values could be useful in predicting aggressiveness of clival chordoma.

Deficiency of PTEN and CDKN2A Tumor-Suppressor Genes in Conventional and Chondroid Chordomas: Molecular Characteristics and Clinical Relevance

Introduction

Chordoma is a malignant tumor predominantly involving the skull base and vertebral column. This study aimed to investigate the molecular characteristics of PTEN and CDKN2A in conventional and chondroid chordomas and their correlation with clinical prognosis.

Materials and Methods

A total of 42 patients were enrolled, including 26 patients with conventional chordoma and 16 patients with chondroid chordoma. Clinicopathological profiles and tissue specimens were collected. Gene sequencing and fluorescence in situ hybridization were performed to identify genetic alterations in the PTEN and CDKN2A genes. Immunohistochemical staining was used for semiquantitative evaluation of PTEN and CDKN2A expression.

Results

Gene sequencing revealed an intron SNP (c.80–96A>G) and a missense mutation (c.10G>A; p.Gly4Arg) in the PTEN gene and a missense mutation (c.442G>A; p.Ala148Thr) in the CDKN2A gene. Loss of the PTEN locus was identified in 25 (59.5%) cases, and loss of the CDKN2A locus was found in 28 (66.7%) cases. There was no significant correlation between progression-free survival (PFS)/overall survival (OS) and loss of PTEN or CDKN2A. The patients with lower PTEN expression showed significantly shorter PFS and OS than those with higher expression, while there was no significant difference in PFS or OS between patients with lower CDKN2A expression and those with higher CDKN2A expression.

Conclusion

Our findings delineated the genetic landscape and expression of PTEN and CDKN2A in chordomas. PTEN expression may serve as a prognostic and predictive biomarker for chordomas.

Rationale for the advancement of PI3K pathway inhibitors for personalized chordoma therapy

PURPOSE

Chordomas are rare and serious tumors with few effective treatments outside of aggressive surgery and radiation. Targeted therapies may present a more effective option for a subset of patients with lesions possessing certain genetic biomarkers.

METHODS

A small molecule inhibitor library was tested in patient-derived UM-Chor1 cells to identify targeted therapies with potential efficacy. Targeted exome sequencing of UM-Chor1 and UM-Chor2 cells was performed to investigate genetic aberrations in relevant pathways. Chordoma cell lines were treated with inhibitors of the phosphotidylinositol 3-kinase (PI3K), epidermal growth factor receptor (EGFR), and cyclin dependent kinase (CDK) pathways, and responses were determined using resazurin cell viability assays, Annexin V apoptosis assays, and western blotting. Pan-PI3K inhibitor BKM120 was also tested in five chordoma xenograft models.

RESULTS

Unbiased small molecule profiling nominated PI3K-AKT-mTOR pathway inhibitors as a promising therapy in chordoma, and genetic analyses of UM-Chor1 and UM-Chor2 cell lines revealed aberrations in PTEN, EGFR, and CDKN2A. Treatment of UM-Chor1 and UM-Chor2 with targeted PI3K, EGFR, and CDK inhibitors inhibited growth and proliferation and induced apoptosis more robustly than imatinib, a currently used chordoma therapy. Furthermore, BKM120 significantly inhibited tumor growth in a subset of the xenograft models tested.

CONCLUSION

Targeted therapies, especially those inhibiting PI3K, display promising effects in multiple chordoma cell line and xenograft models. Nevertheless, the limited effects of PI3K, EGFR, and CDK targeting agents in other models reveal the presence of resistance mechanisms, which motivates future research to both identify biomarkers of response and develop combination therapies.

[From bench to bedside for new treatment paradigms in chordomas: An update]

Chordomas are rare malignant tumours, which typically occur in the axial skeleton and skull base. They arise from embryonic remnants of the notochord. They constitute less than 5 % of primary bone tumours. They are characterised by their locally aggressive potential with high frequency of recurrences and a median overall survival of 6 years. The initial therapeutic strategy must be discussed in an expert centre and may involve surgery, preoperative radiotherapy, exclusive radiotherapy or therapeutic abstention. Despite this, more than 50 % of patients will be facing recurrences with few therapeutic options available at this advanced stage. This review aims to outline current treatment options available in chordomas, as well as discussing potentiality of new therapeutic approaches through their molecular characterization and the comprehension of their immunological environment.

Spinal dural resection for oncological purposes: a systematic analysis of risks and outcomes in patients with malignant spinal tumors

OBJECTIVE

Oncological outcomes for many malignant primary spinal tumors and isolated spinal metastases have been shown to correlate with extent of resection. For tumors with dural involvement, some authors have described spinal dural resection at the time of tumor resection in the interest of improving oncological outcomes. The complication profile associated with resection of the spinal dura for oncological purposes, however, and the relative influence of resecting tumor-involved dura on progression-free survival are not well defined. The authors performed a systematic review of the literature and identified cases in which the spinal dura was resected for oncological purposes in the interest of better understanding the associated risks and outcomes of this technique.

METHODS

Electronic databases (PubMed/MEDLINE, Scopus) were systematically searched to identify studies that reported clinical and/or oncological outcomes of patients with malignant spinal neoplasms undergoing resection of tumor-involved dura at the time of surgical intervention.

RESULTS

Ten articles describing 15 patients were included in the analysis. The most common tumor histologies were chordoma (3/15, 20%), giant cell tumor (3/15, 20%), epithelioid sarcoma (2/15, 13.3%), osteosarcoma (2/15, 13.3%), and metastasis (2/15, 13.3%). Procedure-related complications were reported in 40% of patients. A trend was seen toward an increased complication rate in redo (66.7%) versus index (16.7%) operations, but this trend did not reach statistical significance (p = 0.24). New, unexpected postoperative neurological deficits were seen in 3 patients (of 14 reporting, 21.4%). A single patient experienced a profound, unexpected neurological deterioration (paraparesis/paraplegia) after surgery, which reportedly improved considerably at latest follow-up. Tumor recurrence was seen in 3 cases (of 12 reporting, 25%) at a mean of 28.34 ± 21.1 months postoperatively. The overall mean radiographic follow-up period was 49.6 ± 36.5 months.

CONCLUSIONS

Resection of the spinal dura for oncological purposes is rarely performed, although a limited number of reports and small series have demonstrated that it is feasible. Spinal dural resection is primarily performed in patients with isolated, primary spinal neoplasms with an intent to cure. The risk associated with spinal dura resection is nontrivial and the complication profile is significant. The influence of dural resection on oncological outcomes is not well defined, and further study is needed before definitive conclusions may be drawn regarding the oncological benefit of dural resection for any particular patient or pathology.

Long and Very-Long-Chain Ceramides Correlate with A More Aggressive Behavior in Skull Base Chordoma Patients

BACKGROUND

Skull base chordomas are rare tumors arising from notochord. Sphingolipids analysis is a promising approach in molecular oncology, and it has never been applied in chordomas. Our aim is to investigate chordoma behavior and the role of ceramides.

METHODS

Ceramides were extracted and evaluated by liquid chromatography and mass spectrometry in a cohort of patients with a skull base chordoma. Clinical data were also collected and correlated with ceramide levels. Linear regression and correlation analyses were conducted.

RESULTS

Analyzing the association between ceramides level and MIB-1, total ceramides and dihydroceramides showed a strong association (r = 0.7257 and r = 0.6733, respectively) with MIB-1 staining (p = 0.0033 and p = 0.0083, respectively). Among the single ceramide species, Cer C24:1 (r = 0.8814, p ≤ 0.0001), DHCer C24:1 (r = 0.8429, p = 0.0002) and DHCer C18:0 (r = 0.9426, p ≤ 0.0001) showed a significant correlation with MIB-1.

CONCLUSION

Our lipid analysis showed ceramides to be promising tumoral biomarkers in skull base chordomas. Long- and very-long-chain ceramides, such as Cer C24:1 and DHCer C24:1, may be related to a prolonged tumor survival and aggressiveness, and the understanding of their effective biological role will hopefully shed light on the mechanisms of chordoma radio-resistance, tendency to recur, and use of agents targeting ceramide metabolism.

Optimal modality selection in external beam radiotherapy

The goal in external beam radiotherapy (EBRT) for cancer is to maximize damage to the tumour while limiting toxic effects on the organs-at-risk. EBRT can be delivered via different modalities such as photons, protons and neutrons. The choice of an optimal modality depends on the anatomy of the irradiated area and the relative physical and biological properties of the modalities under consideration. There is no single universally dominant modality. We present the first-ever mathematical formulation of the optimal modality selection problem. We show that this problem can be tackled by solving the Karush-Kuhn-Tucker conditions of optimality, which reduce to an analytically tractable quartic equation. We perform numerical experiments to gain insights into the effect of biological and physical properties on the choice of an optimal modality or combination of modalities.

The Degree of Middle and Lower Clivus Invasion by Chordoma is Linked to Patient Prognosis Via Ki-67 Value

OBJECTIVE

The aim of this study was to discuss the relationship between Ki-67 values and the degree to which chordoma invade the clivus and to certify that the prognosis of chordoma is worse when it invades the middle and lower clivus than when it does not.

METHODS

We collected 56 cases of first-time chordoma illness in which patients received no treatment before surgery. Patients underwent craniocerebral magnetic resonance imaging and skull-base 3-dimensional computed tomography scans before the operation. We divided patients into 2 groups depending on the extent to which the middle and lower clivus were invaded. We classified patients with chordoma that did not significantly invade the middle and lower clivuses into a "noninvasive" group and the others into an "invasive" group. Ki-67 values were extracted from the pathological report after surgery. We use an independent χ² test to indicate that Ki-67 values for the invasive group were higher than those for the noninvasive group.

RESULTS

We grouped the data and did a statistical analysis. We found that the Ki-67 values are >5% for most patients in whom chordoma have eroded the middle-lower clivus, whereas it is ≤5% for patients in whom the middle-lower clivus region has not been invaded. Therefore, there is a correlation between Ki-67 value and the region of chordoma invading the clivus.

CONCLUSIONS

Statistical analysis revealed that Ki-67 values when the chordoma invaded the middle and lower clivus were significantly higher than when it did not. Thus, we can conclude that the prognosis is worse when chordoma invade the middle and lower clivus.

Prognostic significance of VEGF receptors expression on the tumor cells in skull base chordoma

BACKGROUND

Chordoma is a rare refractory neoplasm that arises from the embryological remnants of the notochord, which is incurable using any multimodality therapy. Vascular endothelial growth factor (VEGF) is a potent activator of angiogenesis that is strongly associated with the tumor-immune microenvironment. These factors have not been elucidated for chordomas.

METHODS

To evaluate the characteristics of vascular and tumor cells in chordoma, we first analyzed the expression of VEGF receptor (VEGFR) 1, VEGFR2, CD34, and Brachyury in a cell line and 54 tumor tissues. Patients with primary skull base chordomas were divided into the following two groups as per the tumor growth rate: patients with slow progression (SP: < 3 mm/year) and those with rapid progression (RP: ≥ 3 mm/year). Thus, the expressions of VEGF-A, VEGFR 1, and VEGFR2 on tumor cells; tumor infiltrative immune cells, including regulatory T cells (Tregs) and tumor-associated macrophages (TAMs); and immune-checkpoint molecules (PD-1/PD-L1) were analyzed with the clinical courses, especially in a comparison between the two groups.

RESULTS

In chordomas, both VEGFR1 and VEGFR2 were strongly expressed not only on vascular endothelial cells, but also on tumor cells. The recurrent cases showed significantly higher VEGFR1 expressions on tumor cells than the primary cases. The expression of VEGF-A was significantly higher in RP than that in SP group. The numbers of CD163+ TAMs and Foxp3+ Tregs were higher in RP than that in SP group.

CONCLUSIONS

Expression of VEGFR1 and VEGFR2 on tumor cells and immunosuppressive tumor-microenvironment were related to tumor growth in patients with chordomas.

Skull base chordoma treated with proton therapy: A systematic review

Background:

Chordoma located in the skull base is usually a challenging surgical condition. It is often not possible to achieve gross total resection. Residual tumors have been treated with adjuvant focal radiation therapy employing high-energy particles most commonly through proton beam. In this review, we systematically analyzed indications and outcomes of this treatment with respect to local control rates of the lesion and factors determining recurrence of skull base chordomas. In addition, we collected data on treatment-associated radiation-induced side effects.

Methods:

In line with the PRISMA guidelines, the authors performed a literature search algorithm for relevant articles using three databases: PubMed, Embase, and Cochrane. Inclusion and exclusion criteria were applied to evaluate all identified studies published between 1980 and 2018.

Results:

Our review included 11 studies for analysis (n = 511 patients). The mean age of the study population was 47.3 ± 5.8 years. The mean dose of postsurgical irradiation at the time of initial treatment was 71.1 ± 3.1 Gy. The mean follow-up duration was 45.0 ± 17.5 months. Within this follow-up duration, recurrence occurred in 26.8% of the patients. The mean time to recurrence was 34.5 ± 15.2 months. A significant number of patients experienced side effects varying from Grade 1 (mild dermatitis) to Grade 4 (temporal lobe necrosis and visual disorders).

Conclusion:

Despite advances in proton therapy, recurrence rates in skull base chordoma remain high. The toxicity of proton therapy may be more prevalent than generally thought. Unfortunately, there is substantial variation in the methods of data reporting.

Benign notochordal cell tumour: clinicopathology and molecular profiling of 13 cases

Aims

To study the clinicopathological and molecular features of benign notochordal cell tumours (BNCTs) and their differential diagnosis from chordoma.

Methods

13 cases of BNCT were investigated. The genome-wide copy number imbalances were performed using Oncoscan CNV array in three cases and fluorescence in situ hybridisation (FISH) detection of epidermal growth factor receptor (EGFR)/chromosome 7 enumeration probe (CEP7), LSI1p36/1q21, LSI19p13/19q13, CEP3/CEP12 and Telvysion 6 P was performed in 13 cases.

Results

All 13 BNCTs were symptomatic and eight cases showed a close relationship with the bones of the skull base. The important histological character for differential diagnosis with chordoma was the absence of extracellular matrix and eosinophil cells and the presence of vacuoles in most tumour cells. Immunohistochemical staining of AE1/AE3, vimentin, epithelial membrane antigen, S-100 and brachyury (100% each) were positive in BNCTs. Gain of chromosome 7 occurred in 10 cases (76.9%), gain of 1p in four (30.8%), gain of 1q in five (38.5%), gain of 19p and 19q in five (38.5%), gain of chromosome 12 in 11 cases (84.6%), gain of 6p in eight (61.5%) and gain of chromosome 3 in four cases (30.8%).

Conclusions

In contrast to chordoma, chromosome gain or normal copy number was more common while chromosome loss was infrequent in BNCTs. This may be a differential diagnosis clue for chordoma and may be an important characteristic in the progression of notochordal cell tumours.

Clinical outcome of proton therapy for patients with chordomas

Purpose

To investigate the clinical outcome of proton therapy (PT) in patients with chordoma.

Materials and Methods

Fifty-eight patients with chordoma treated with PT between June 2007 and December 2015 at the National Cancer Center, Korea, were retrospectively analyzed. The median total dose was 69.6 cobalt gray equivalent (CGE; range, 64.8 to 79.2 CGE). Local progression-free survival (LPFS), distant metastasis-free survival (DMFS), overall survival (OS), and diseasespecific survival (DSS) rates were calculated by the Kaplan–Meier method.

Results

With the median follow-up of 42.8 months (range, 4 to 174 months), the 5-year LPFS, DMFS, OS, and DSS rates were 87.9%, 86.7%, 88.3%, and 92.9%, respectively. The tumor location was associated with the patterns of failure: the LPFS rates were lower for cervical tumors (57.1%) than for non-cervical tumors (93.1%) (p = 0.02), and the DMFS rates were lower for sacral tumors (53.5%) than for non-sacral tumors (100%) (p = 0.001). The total dose was associated with both the LPFS rate and DMFS rate. The initial tumor size was associated with the DMFS rate, but was not associated with the LPFS rate. Three patients had grade 3 late toxicity with none ≥grade 4.

Conclusion

PT is an effective and safe treatment in patients with chordomas. The tumor location was associated with the patterns of failure: local failure was common in cervical tumors, and distant failure was common in sacral tumors. Further refinement of PT, such as the utilization of intensity modulated PT for cervical tumors, is warranted to improve the outcome.

Clival Chondroid Chordoma: A Case Report and Review of the Literature

Chordomas are rare, slow-growing, and locally aggressive malignant neoplasms derived from primitive notochord remnants. The chondroid variety represents 14% of all chordomas mainly developing in the spheno-occipital region and presenting between the third and fifth decades of life. When developing intracranially, symptoms can range from headaches and neck pain to cranial nerve neuropathies and facial numbness. We illustrate a case of an adolescent woman who presented with excruciating facial pain, otalgia, decreased visual acuity, quadriparesis, headache, nausea, and dysphagia. Radiological studies revealed a large heterogeneous mass in the spheno-occipital region with clivus destruction. Biopsy and histopathology confirmed the diagnosis. Proper identification with prompt surgical resection and adjuvant radiotherapy remains critical to prevent complications.

Endoscopic endonasal approaches for the management of cranial base malignancies: histologically guided treatment and clinical outcomes

Malignancies of the skull base represent a highly diverse and challenging set of pathologies which exhibit a wide array of oncologic behavior. In recent decades, a number of important advances in treatment technique have evolved to improve oncologic outcomes and reduce morbidity in the treatment of these aggressive cancers. Intensity modulated radiation therapy has become the gold standard in radiotherapy owing to its precision planning and reduced morbidity. However heavy ion particle radiation (proton therapy, carbon ion, etc.) are recently emerging with promising results at the skull base related to the reduced exit dose to adjacent structures. Novel systemic therapeutics such as targeted and immunotherapies may dramatically alter the treatment paradigm for many of these pathologies. Nevertheless, most skull base malignancies remain surgical diseases. The evolution of the expanded endonasal approach for a minimally invasive surgical resection has proven validity in treating many of these pathologies when properly selected, and have largely supplanted open approaches owing to the reduced morbidity profile. In spite of these important advances, the most critical aspect in comprehensive treatment is a detailed understanding of the oncologic behavior and outcomes data for each of the specific histopathologies encountered at the skull base. The nuances in management strategy, histologic profile, and surveillance planning can be stratified through the development of a comprehensive, multidisciplinary skull base team to maximize therapeutic effect and minimize morbidity for each patient. This review aims to summarize the key body of data and approaches for each of the histologies frequently encountered in the skull base, while highlighting the value and technique of endonasal approaches.

Tumor Reduction with Pazopanib in a Patient with Recurrent Lumbar Chordoma

Introduction

Chordomas are rare malignancies of bone origin that occur in the axial skeleton, typically the skull base and lumbar/sacral regions. Although often classified as low-grade neoplasms, its locally infiltrative behavior may result in significant morbidity and mortality. Optimal surgical resection may be curative, but up to 50% of the cases relapse within 5 years, and currently there are no systemic treatments approved in this setting. A large proportion of these tumors express stem-cell factor receptor (c-KIT) and platelet-derived growth factor receptors (PDGFRs), providing a rationale for the use of tyrosine-kinase inhibitors (TKIs).

Case report

A 27-year-old male presented with recurrent chordoma of the lumbar spine 4 years after initial diagnosis. Salvage therapies in the interval included repeat resections and radiation therapy. He ultimately developed multifocal recurrence not amenable to complete excision or reirradiation. A comprehensive genomic profiling assay was performed and revealed nondrugable alterations. Decision was made to proceed with systemic treatment with pazopanib 800 mg/day, resulting in tumor reduction (-23.1% reduction in size) and prolonged disease control.

Conclusion

For this patient with a multiple recurrent chordoma and limited treatment options, pazopanib resulted in sustained clinical benefit following initial tumor reduction.

Surgical Resection and Adjuvant Radiation Therapy in the Treatment of Skull Base Chordomas

OBJECTIVE

Chordomas are rare tumors of notochordal origin that are known to be locally aggressive and are often treated with surgical resection followed by adjuvant radiation therapy (RT). The accepted standard of treatment for chordomas of the mobile spine, which includes en-bloc resection with wide margins, cannot be easily applied to the chordomas of the skull base because of their proximity to critical neurovascular structures. We describe our experience with the role of surgery and adjuvant RT in the treatment of chordomas over 16 years.

METHODS

We performed a retrospective chart review on patients with diagnoses of clival chordoma between the years 2000 and 2015 at Northwestern Memorial Hospital. We reviewed presenting symptoms, tumor location and size, extent of resection, complications, recurrence, adjuvant treatment, and follow-up duration.

RESULTS

A total of 20 patients underwent 32 surgeries. Of the 20 initial surgeries, 80% underwent gross total resection, and 20% had subtotal resection. The mean follow-up time was 60.75 months. Mean tumor volume was 23.07 cm³. Most common presenting signs and symptoms were headaches (70%), cranial nerve palsies (45%), and diplopia (55%). Diplopia was defined as complaints of double vision without any objective evidence of a cranial nerve palsy. Median time to progression was 57 months, and median overall survival was 136 months. Initial tumor volume and the need for a second dose of RT either as sole or as adjuvant treatment of a recurrence had a statistically significant effect on progression-free survival (P = 0.009, 0.009). None of the factors studied had a statistically significant effect on overall survival.

CONCLUSIONS

The treatment of chordomas remain challenging and requires multimodal treatment strategies spanning different specialties. Initial tumor size and need for second dose of RT for recurrence appear to play a significant role in progression-free survival. Adjuvant RT after gross total resection may play a role in improved progression-free and overall survival in patients with clival chordomas.

Humeral metastasis of sacrococcygeal chordoma detected by fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography: A case report

Chordomas are rare, slow-growing, locally aggressive bone tumors arising from embryonic remnants of the notochord. Distant metastases most commonly involve the lung, liver, axial skeleton, skin, and lymph nodes. Humeral metastases are extremely rare. We report the case of a recurrent chordoma with humeral metastasis, complicated with pathologic fracture. Fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography revealed multiple hypermetabolic skeletal lesions, corresponding to the symptoms. Our report suggests that positron emission tomography-computed tomography is useful for evaluation of recurrence and distant metastases of chordomas.

Immunophenotypic features of dedifferentiated skull base chordoma: An insight into the intratumoural heterogeneity

Chordomas are rare and low-grade malignant solid tumours, despite their histologically benign appearance, that arise in the bone from embryonic notochordal vestiges of the axial skeleton, a mesoderm-derived structure that is involved in the process of neurulation and embryonic development. Chordomas occurring in the skull base tend to arise in the basiocciput along the clivus. Three major morphological variants have been described (classical, chondroid, and atypical/dedifferentiated). The pathogenesis and molecular mechanisms involved in chordoma development remain uncertain. From a pathological standpoint, the microenvironment of a chordoma is heterogeneous, showing a dual epithelial-mesenchymal differentiation. These tumours are characterised by slow modality of biologic growth, local recurrence, low incidence of metastasis rates, and cancer stem cell (CSC) phenotype. The main molecular findings are connected with brachyury immunoexpression and activation of the downstream Akt and mTOR signalling pathways. The differentiation between typical and atypical chordomas is relevant because the tumoural microenvironment and prognosis are partially different. This review provides an insight into the recent and relevant concepts and histochemical markers expressed in chordomas, with special emphasis on dedifferentiated chordomas and their prognostic implications.

An unusual case of oropharyngeal chordoma: A case report and literature review

RATIONALE

Chordomas are rare malignant neoplasms derived from incomplete regression of notochordal tissue along the cranio-coccygeal axis. Chordomas that develop in an atypical position are called ectopic chordomas, such as oropharyngeal chordomas (OCs). OCs are exceedingly rare; only 11 cases have been reported to date. Preoperative diagnosis is challenging, and an accurate diagnosis thus is based on postoperative pathologic examination findings and immunohistochemistry. Although surgical therapy and radiotherapy is performed in some patients, the 5-year survival rate is low. Increasingly more studies of chordomas have been based on molecular biology to increase the survival rate, and targeted therapy could be a new therapy in the future.

PATIENT CONCERNS

The patient presented with a left oropharyngeal mass that had begun slowly enlarging 1 year previously. He reported a foreign body sensation and dysphonia during this time period.

DIAGNOSES

The patient was initially diagnosed with a neurogenic tumor. Routine postoperative pathology showed that the mass was consistent with a chordoma.

INTERVENTION

Mass resection was performed.

OUTCOME

One year after the initial surgery, magnetic resonance imaging revealed block signal images at the left retropharyngeal space and clivus. The patient developed recurrence of the OC.

LESSONS

Surgical resection is the mainstay of treatment for OC, and postoperative adjuvant radiotherapy is also important. An understanding of the unusual case described in this report may be helpful in diagnosing OC, and development of targeted therapy may help clinicians to provide novel treatment for patients with OC.

Long-term follow-up after endoscopic trans-sphenoidal surgery or initial observation in clivus chordomas

BACKGROUND

Resection of clivus chordomas through extensive skull base approaches is associated with high mortality and morbidity even in experienced hands. We report our experience with endoscopic trans-sphenoidal surgery, or a "wait-and-scan" strategy in selected patients.

METHOD

Ten patients were diagnosed with clivus chordomas during an 8-year period. Six patients underwent primary treatment with endoscopic trans-sphenoidal surgery, followed by adjuvant proton-beam therapy in three of these patients. Four patients with minor symptoms were followed-up untreated. Mean follow-up was 91 months.

RESULTS

Of the six patients operated on, total or gross total resection was achieved in four, partial resection in one and biopsy was taken in one. Preoperative cranial neuropathies resolved in three out of five patients, and no new cranial nerve palsies were encountered. Postoperative cerebrospinal fluid leak occurred in one patient. Four patients were initially followed-up without any treatment, and three of these have remained stable without tumour progression for a mean of 94 months. Due to a slow, though progressive growth of tumour, one patient was operated on after 80 months of initial observation.

CONCLUSIONS

The natural course of clivus chordomas has yet to be defined. The endoscopic trans-sphenoidal approach is a valid, minimally invasive alternative for the treatment of clival chordomas, and in selected patients a "wait and scan" strategy can be considered. Our long-term results show low mortality and good functional outcome. An endonasal endoscopic trans-sphenoidal approach should be a principal part of the armamentarium of surgeons treating clivus chordomas.

Surgical resection of skull-base chordomas: experience in case selection for surgical approach according to anatomical compartments and review of the literature

BACKGROUND

Chordoma is a rare bony malignancy known to have a high rate of local recurrence after surgery. The best treatment paradigm is still being evaluated. We report our experience and review the literature. We emphasize on the difference between endoscopic and open craniotomy in regard to the anatomical compartment harboring the tumor, the limitations of the approaches and the rate of surgical resection.

METHOD

We retrospectively collected all patients with skull-base chordomas operated on between 2004 and 2014. Detailed radiological description of the compartments being occupied by the tumor and the degree of surgical resection is discussed.

RESULTS

Eighteen patients were operated on in our facility for skull-base chordoma. Seventeen endoscopic surgeries were done in 15 patients, and 7 craniotomies were done in 5 patients. The mean age was 48.9 years (±19.8 years). When reviewing the anatomical compartments, we found that the most common were the upper clivus (95.6%) and lower clivus (58.3%), left cavernous sinus (66.7%) and petrous apex (∼60%). Most of the patients had intradural tumor involvement (70.8%). In all craniotomy cases, there was residual tumor in multiple compartments. In the endoscopic cases, the most difficult compartments for total resection were the lower clivus, and lateral extensions to the petrous apex or cavernous sinus.

CONCLUSIONS

Our experience shows that the endoscopic approach is a good option for midline tumors without significant lateral extension. In cases with very lateral or lower extensions, additional approaches should be added trying to achieve complete resection.

Establishment and genomic characterization of the new chordoma cell line Chor-IN-1

Chordomas are rare, slowly growing tumors with high medical need, arising in the axial skeleton from notochord remnants. The transcription factor “brachyury” represents a distinctive molecular marker and a key oncogenic driver of chordomas. Tyrosine kinase receptors are also expressed, but so far kinase inhibitors have not shown clear clinical efficacy in chordoma patients. The need for effective therapies is extremely high, but the paucity of established chordoma cell lines has limited preclinical research. Here we describe the isolation of the new Chor-IN-1 cell line from a recurrent sacral chordoma and its characterization as compared to other chordoma cell lines. Chor-IN-1 displays genomic identity to the tumor of origin and has morphological features, growth characteristics and chromosomal abnormalities typical of chordoma, with expression of brachyury and other relevant biomarkers. Chor-IN-1 gene variants, copy number alterations and kinome gene expression were analyzed in comparison to other four chordoma cell lines, generating large scale DNA and mRNA genomic data that can be exploited for the identification of novel pharmacological targets and candidate predictive biomarkers of drug sensitivity in chordoma. The establishment of this new, well characterized chordoma cell line provides a useful tool for the identification of drugs active in chordoma.

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.

Notochordal Tumors: An Update on Molecular Pathology with Therapeutic Implications

Recent molecular investigations of chordoma show common expression of various receptor tyrosine kinases and activation of downstream signaling pathways contributing to tumor growth and progression. The transcription factor brachyury (also known as T) is important in notochord differentiation, and germline duplication of the gene is often found in familial chordomas. Nuclear expression of brachyury is consistent in chordoma and in benign notochordal cell tumor. Based on the molecular evidence, targeting of several kinds of molecular agents has been attempted for the treatment of uncontrolled chordomas and achieved partial response or stable condition in many cases.

EM proves invaluable in the confirmation of chordoma in the sacral mass of a middle-aged man

A case of a 47-year-old male with a sacral spine mass was investigated by histology, immunohistochemistry (IHC), and electron microscopy (EM). The light microscopy of the first core biopsy revealed scant cellularity with spindle and round cells with eosinophilic cytoplasm within a fibromyxoid background. Immunostaining with pancytokeratin, cytokeratin 19, and S100 was nonspecific. Another biopsy was attempted to obtain a more definitive diagnosis. Light microscopy of the second core had scant cellular material. However, the tissue was specifically requested for ultrastructural evaluation and revealed features diagnostic of chordoma. After definitive diagnosis, radical resection of the mass was performed. This case illustrates how EM was instrumental in the definitive diagnosis before radical resection in a case that was not clear by hematoxylin and eosin (H&E) and IHC alone.

Spinal stereotactic body radiotherapy following intralesional curettage with separation surgery for initial or salvage chordoma treatment

OBJECTIVE Chordoma is a rare malignant tumor for which en bloc resection with wide margins is advocated as primary treatment. Unfortunately, due to anatomical constraints, en bloc resection to achieve wide or marginal margins is not feasible for many patients as the resulting morbidity would be prohibitive. The objective of this study was to evaluate the efficacy of intralesional curettage and separation surgery followed by spinal stereotactic body radiation therapy (SBRT) in patients with chordomas in the mobile spine. METHODS The authors performed a retrospective chart review of all patients with chordoma in the mobile spine treated from 2004 to 2016. Patients were identified from a prospectively collected database. Initially 22 patients were identified with mobile spine chordomas. With inclusion criteria of cytoreductive separation surgery followed closely by SBRT and a minimum of 6 months of follow-up imaging, 12 patients were included. Clinical and pathological characteristics of each patient were collected and data were analyzed. Patients were divided into two cohorts-those undergoing intralesional resection followed by SBRT as initial chordoma treatment at Memorial Sloan Kettering Cancer Center (MSKCC) (Cohort 1) and those undergoing salvage treatment following recurrence (Cohort 2). Treatment toxicities were classified according to the Common Terminology Criteria for Adverse Events version 4.03. Overall survival was analyzed using Kaplan-Meier analysis. RESULTS The 12 patients had a median post-SBRT follow-up time of 26 months. Cohort 1 had 5 patients with median post-SBRT follow-up time of 65.9 months and local control rate of 80% at last follow-up. Only one patient had disease progression, at 48.2 months following surgery and SBRT. Cohort 2 had 7 patients who had been treated at other institutions prior to undergoing both surgery and SBRT (salvage therapy) at MSKCC. The local control rate was 57.1% and the median follow-up duration was 10.7 months. One patient required repeat irradiation. Major surgery- and radiation-related complications occurred in 18% and 27% of patients, respectively. Epidural spinal cord compression scores were collected for each patient pre- and postoperatively. CONCLUSIONS The combination of surgery and SBRT provides excellent local control following intralesional curettage and separation surgery for chordomas in the mobile spine. Patients who underwent intralesional curettage and spinal SBRT as initial treatment had better disease control than those undergoing salvage therapy. High-dose radiotherapy may offer several biological benefits for tumor control.

Extended maxillotomy for skull base access in contemporary management of chordomas: Rationale and technical aspect

Minimally invasive approaches to the central skull base have been popularized over the last decade and have to a large extent displaced 'open' procedures. However, traditional skull base surgery still has its role especially when dealing with a large clival chordoma where maximal surgical resection is the principal goal to maximize patient survival. In this paper, we present a case of a 25year-old male patient with chordoma in the inferior clivus which was initially debulked via a transnasal endoscopic approach. He unfortunately had a large recurrence of tumor requiring re-do resection. With the aim to achieve maximal surgical resection, we then chose the technique of a transoral approach with Le Fort 1 maxillotomy and midline palatal split. Post-operative course for the patient was uneventful and post-operative MRI confirmed significant debulking of the clival lesion. The technique employed for the surgical procedure is presented here in detail as is our experience over two decades using this technique for tumors, inflammatory lesions and congenital abnormalities at the cranio-cervical junction.

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.

Clinical Decision Making: Integrating Advances in the Molecular Understanding of Spine Tumors

STUDY DESIGN

Literature review.

OBJECTIVE

To describe advancements in molecular techniques, biomarkers, technology, and targeted therapeutics and the potential these modalities hold to predict treatment paradigms, clinical outcomes, and/or survival in patients diagnosed with primary spinal column tumors.

SUMMARY OF BACKGROUND DATA

Advances in molecular technologies and techniques have influenced the prevention, diagnosis, and overall management of patients diagnosed with cancer. Assessment of genomic, proteomic alterations, epigenetic, and posttranslational modifications as well as developments in diagnostic modalities and targeted therapeutics, although the best studied in nonspinal metastatic disease, have led to increased understanding of spine oncology that is expected to improve patient outcomes. In this manuscript, the technological advancements that are expected to change the landscape of spinal oncology are discussed with a focus on how these technologies will aid in clinical decision-making for patients diagnosed with primary spinal tumors.

METHODS

A review of the literature was performed focusing on studies that integrated next-generation sequencing, circulating tumor cells/circulating tumor DNA, advances in imaging modalities and/or radiotherapy in the diagnosis and treatment of cancer.

RESULTS

We discuss genetic and epigenetic drivers, aberrations in receptor tyrosine kinase signaling, and emerging therapeutic strategies that include receptor tyrosine kinase inhibitors, immunotherapy strategies, and vaccine-based cancer prevention strategies.

CONCLUSION

The wide range of approaches currently in use and the emerging technologies yet to be fully realized will allow for better development of rationale therapeutics to improve patient outcomes.

LEVEL OF EVIDENCE

N/A.

A Prospective Outcomes Study of Proton Therapy for Chordomas and Chondrosarcomas of the Spine

PURPOSE

To evaluate the effectiveness of definitive or adjuvant external beam proton therapy on survival in patients with chordomas and chondrosarcomas of the spine.

METHODS AND MATERIALS

Between March 2007 and May 2013, 51 patients with a median age of 58 years (range, 22-83 years) with chordoma (n=34) or chondrosarcomas (n=17) of the sacrum (n=21), the cervical spine (n=20), and the thoracolumbar spine (n=10) were treated with external beam proton therapy to a median dose of 70.2 Gy(RBE) [range, 64.2-75.6 Gy(RBE)] at our institution. Distant metastases, overall survival, cause-specific survival, local control, and disease-free survival were calculated.

RESULTS

The mean follow-up time was 3.7 years (range, 0.3-7.7 years). Across all time points, 25 patients experienced disease recurrence: 18 local recurrences, 6 local and distant recurrences, and 1 distant metastasis. The 4-year rates of overall survival and cause-specific survival were 72%; disease-free survival was 57%, local control was 58%, and freedom from distant metastases was 86%. The median time to local progression was 1.7 years (range, 0.2-6.0 years), and the median time to distant progression was 1.6 years (range, 0.2-6.0 years). The risk factors for local recurrence were age ≤58 years (62% vs 26%; P=.04) and recurrence after prior surgery (29% vs 81%; P=.01). Secondary cancers developed in 2 patients: B-cell lymphoma 5.5 years after treatment and bladder cancer 2 years after treatment. We observed the following toxicities: sacral soft tissue necrosis requiring surgery (n=2), T1 vertebral fracture requiring fusion surgery (n=1), chronic urinary tract infections (n=1), surgery for necrotic bone cyst (n=1), and grade 2 bilateral radiation nephritis (n=1).

CONCLUSION

High-dose proton therapy controls more than half of spinal chordomas and chondrosarcomas and compares favorably with historic photon data. Local progression is the dominant mode of treatment failure and may be reduced by treating patients at the time of initial diagnosis. The impact of age is a novel finding of this study.

Proton beam therapy in the management of skull base chordomas: systematic review of indications, outcomes, and implications for neurosurgeons

BACKGROUND

Chordomas are rare tumours affecting the skull base. There is currently no clear consensus on the post-surgical radiation treatments that should be used after maximal tumour resection. However, high-dose proton beam therapy is an accepted option for post-operative radiotherapy to maximise local control, and in the UK, National Health Service approval for funding abroad is granted for specific patient criteria.

OBJECTIVES

To review the indications and efficacy of proton beam therapy in the management of skull base chordomas. The primary outcome measure for review was the efficacy of proton beam therapy in the prevention of local occurrence.

METHODS

A systematic review of English and non-English articles using MEDLINE (1946-present) and EMBASE (1974-present) databases was performed. Additional studies were reviewed when referenced in other studies and not available on these databases. Search terms included chordoma or chordomas. The PRISMA guidelines were followed for reporting our findings as a systematic review.

RESULTS

A total of 76 articles met the inclusion and exclusion criteria for this review. Limitations included the lack of documentation of the extent of primary surgery, tumour size, and lack of standardised outcome measures. Level IIb/III evidence suggests proton beam therapy given post operatively for skull base chordomas results in better survival with less damage to surrounding tissue.

CONCLUSIONS

Proton beam therapy is a grade B/C recommended treatment modality for post-operative radiation therapy to skull base chordomas. In comparison to other treatment modalities long-term local control and survival is probably improved with proton beam therapy. Further, studies are required to directly compare proton beam therapy to other treatment modalities in selected patients.

Tumor Cells Surviving Exposure to Proton or Photon Radiation Share a Common Immunogenic Modulation Signature, Rendering Them More Sensitive to T Cell-Mediated Killing

PURPOSE

To provide the foundation for combining immunotherapy to induce tumor antigen-specific T cells with proton radiation therapy to exploit the activity of those T cells.

METHODS AND MATERIALS

Using cell lines of tumors frequently treated with proton radiation, such as prostate, breast, lung, and chordoma, we examined the effect of proton radiation on the viability and induction of immunogenic modulation in tumor cells by flow cytometric and immunofluorescent analysis of surface phenotype and the functional immune consequences.

RESULTS

These studies show for the first time that (1) proton and photon radiation induced comparable up-regulation of surface molecules involved in immune recognition (histocompatibility leukocyte antigen, intercellular adhesion molecule 1, and the tumor-associated antigens carcinoembryonic antigen and mucin 1); (2) proton radiation mediated calreticulin cell-surface expression, increasing sensitivity to cytotoxic T-lymphocyte killing of tumor cells; and (3) cancer stem cells, which are resistant to the direct cytolytic activity of proton radiation, nonetheless up-regulated calreticulin after radiation in a manner similar to non-cancer stem cells.

CONCLUSIONS

These findings offer a rationale for the use of proton radiation in combination with immunotherapy, including for patients who have failed radiation therapy alone or have limited treatment options.

The clinical trial landscape in oncology and connectivity of somatic mutational profiles to targeted therapies

Background

Precision medicine in oncology relies on rapid associations between patient-specific variations and targeted therapeutic efficacy. Due to the advancement of genomic analysis, a vast literature characterizing cancer-associated molecular aberrations and relative therapeutic relevance has been published. However, data are not uniformly reported or readily available, and accessing relevant information in a clinically acceptable time-frame is a daunting proposition, hampering connections between patients and appropriate therapeutic options. One important therapeutic avenue for oncology patients is through clinical trials. Accordingly, a global view into the availability of targeted clinical trials would provide insight into strengths and weaknesses and potentially enable research focus. However, data regarding the landscape of clinical trials in oncology is not readily available, and as a result, a comprehensive understanding of clinical trial availability is difficult.

Results

To support clinical decision-making, we have developed a data loader and mapper that connects sequence information from oncology patients to data stored in an in-house database, the JAX Clinical Knowledgebase (JAX-CKB), which can be queried readily to access comprehensive data for clinical reporting via customized reporting queries. JAX-CKB functions as a repository to house expertly curated clinically relevant data surrounding our 358-gene panel, the JAX Cancer Treatment Profile (JAX CTP), and supports annotation of functional significance of molecular variants. Through queries of data housed in JAX-CKB, we have analyzed the landscape of clinical trials relevant to our 358-gene targeted sequencing panel to evaluate strengths and weaknesses in current molecular targeting in oncology. Through this analysis, we have identified patient indications, molecular aberrations, and targeted therapy classes that have strong or weak representation in clinical trials.

Conclusions

Here, we describe the development and disseminate system methods for associating patient genomic sequence data with clinically relevant information, facilitating interpretation and providing a mechanism for informing therapeutic decision-making. Additionally, through customized queries, we have the capability to rapidly analyze the landscape of targeted therapies in clinical trials, enabling a unique view into current therapeutic availability in oncology.

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.