Chordoma: natural history and treatment results in 33 cases

The role of tumor immune microenvironment in chordoma: promising immunotherapy strategies

Chordoma is a rare malignant bone tumor with limited therapeutic options, which is resistant to conventional chemotherapy and radiotherapy, and targeted therapy is also shown with little efficacy. The long-standing delay in researching its mechanisms of occurrence and development has resulted in the dilemma of no effective treatment targets and no available drugs in clinical practice. In recent years, the role of the tumor immune microenvironment in driving tumor growth has become a hot and challenging topic in the field of cancer research. Immunotherapy has shown promising results in the treatment of various tumors. However, the study of the immune microenvironment of chordoma is still in its infancy. In this review, we aim to present a comprehensive reveal of previous exploration on the chordoma immune microenvironment and propose promising immunotherapy strategies for chordoma based on these characteristics.

Advancement of PI3 Kinase Inhibitor Combination Therapies for PI3K-Aberrant Chordoma

Objectives  Targeted inhibitors of the PI3 kinase (PI3K) pathway have shown promising but incomplete antitumor activity in preclinical chordoma models. The aim of this study is to advance methodology for a high-throughput drug screen using chordoma models to identify new combination therapies for chordoma. Study Design  Present work is an in vitro study. Setting  The study conducted at an academic research laboratory. Materials and Methods  An in vitro study on automated high-throughput screening of chordoma cells was performed using a library of 1,406 drugs as both mono- and combination therapies with PI3K inhibitors. Combination indices were determined for dual therapies and synergistic outliers were identified as potential therapeutic agents. T (brachyury) siRNA knockdown in combination with PI3K pathway inhibition was also assessed. Results  Fifty-nine combination therapies were identified as having potential therapeutic efficacy. Effective combinations included PI3K inhibitors with GSK1838705A (ALK/IGF-1R inhibitor), LY2874455 (VEGFR/FGFR inhibitor), El1 (selective Ezh2 inhibitor), and (-)-p-bromotetramisole oxalate (alkaline phosphatase inhibitor). The top ranking targets identified included ALK, PDGFR, VEGFR, aurora kinase, and BCL-2. T (brachyury) inhibition produced significant reduction in cell viability and growth; however PI3K inhibition in combination with T (brachyury) knockdown did not result in further reduction in growth and viability in vitro. Conclusion  High throughput with in vitro combination screening is feasible with chordoma cells and allows for rapid identification of synergistic dual-therapies. Potential combination therapies and targetable pathways were identified. T (brachyury) knockdown produced significant reduction in cell viability, but did not show additional benefit with PI3K pathway inhibition in this model. Further in vitro and in vivo validation of these therapeutic combinations is warranted.

Partial sacrectomy with patient-specific osteotomy guides

Background

Chordomas are rare, locally aggressive, malignant tumors. Surgical resection with sufficient margins defines the outcome. However, the necessity for wide margins often leads to sacrifice of important neurological structures. 3D-printed osteotomy guides are a promising solution for precise execution of surgical resection. We present probably the first sacrococcygeal chordoma resection with 3D-printed guides.

Methods

The case of a 49-year-old woman with a sacrococcygeal chordoma, resected with help of 3-D pre-operative planning and patient-specific 3D-printed osteotomy guides, is reported in detail.

Results

A sufficient tumor excision could be performed successfully while sparing nerve root S4. The planed margin has been exactly maintained, as confirmed by histology. The patient demonstrated an excellent clinical outcome with no evidence of local recurrence.

Conclusions

3-D pre-operative planning and patient-specific osteotomy guides can be used for planning and performing en-bloc surgical resection of sacral chordomas.

Surgical Management of Spinal Chordoma: A Systematic Review and Single-Center Experience

OBJECTIVE

Chordoma is a rare neoplasm of the neuraxis derived from remnants of the primitive notochord. The importance of wide margins and use of adjuvant therapy in spinal chordomas are still contentious points in the management of spinal chordomas. We conducted a systematic review of the surgical management of spinal chordomas alongside our 10-year institutional experience.

METHODS

A systematic search of the literature was performed in November 2020 using Embase and MEDLINE for articles regarding the surgical management of chordomas arising from the mobile spine and sacrum. We also searched for all adult patients who were surgically managed for spinal chordomas at our institute between 2010 and 2020. In both the systematic review and our institutional case series, data on adequacy of resection, use of adjuvant therapy, complications, recurrence (local or metastatic), and survival outcomes were collected.

RESULTS

We identified and analyzed 42 articles, yielding 1531 patients, from which the overall gross total or wide resection rate was 54.9%. Among the 8 cases in our institutional experience (4 sacral, 3 cervical, and 1 lumbar), we achieved gross total resection in 50% of initial operations. The recurrence rate was 25% in our gross total resection group and 50% where initial resection was subtotal. Of patients, 75% had no evidence of recurrence at most recent follow-up.

CONCLUSIONS

Albeit difficult at times because of the proximity to neurovascular tissue, achieving a wide resection followed by adjuvant therapy for spinal chordomas is of great importance. Multidisciplinary discussion is valuable to ensure the best outcome for the patient.

Survival and treatment of cranial and spinal chordomas: a population-based study

Chordomas are rare, slow-growing malignant tumors. Given the paucity of data of the disease, the treatment strategies are disputed. We collected clinical and survival information of patients with chordoma diagnosed between 1975 and 2016 from the Surveillance, Epidemiology, and End Results database. A total of 1797 patients were initially enrolled, including 762 (42.4%) cranial and 1035 (57.6%) spinal chordoma. A total of 1504 patients were further evaluated after screening. In the cranial group, the surgery (gross total resection (GTR): p = 0.001 for overall survival (OS); p = 0.009 for cancer-specific survival (CSS)), tumor extension (distant metastasis: p = 0.001 for OS; p = 0.002 for CSS), and the age (p < 0.001 for OS) were independent prognostic factors for survival. In the spinal group, the age (p = 0.004), location (p < 0.001), GTR (p < 0.001), and tumor extension (distant metastasis, p < 0.001) were independent prognostic factors for OS; the age (p = 0.007), histological type (p < 0.001), GTR (p < 0.001), radiation (p = 0.018), chemotherapy (p = 0.006), and tumor extension (p < 0.001) were independent prognostic factors for CSS. In this large cohort, a significant association was noted between extent of resection and outcome. Even though adjuvant radiation or chemotherapy did not benefit patients with chordoma, the effect on prognosis can be explored in a further study based on our findings.

[Multidisciplinary management of clival chordoma]

Chordoma of the clivus belong to the rare tumors of the skull base. Due to their aggresive behaviour including intradural infiltration of neurovascular structures an interdisciplinary treatment is mandatory. This article gives an overview on current surgical concepts including the endoscopic approach as well as the postoperative radiotherapy. Novel diagnostic tools and molecular targets to optimize individual tumor therapy are discussed.

Partial response to erlotinib in a patient with imatinib-refractory sacral chordoma

Background

Chordoma is a rare, slow growing and locally aggressive mesenchymal neoplasm with uncommon distant metastases. It is a chemo-resistant disease with surgery and radiotherapy being the mainstay in treatment of localized disease. In advanced disease imatinib has a role. We report a case of metastatic sacral chordoma with symptomatic and radiological response to erlotinib post-progression on imatinib.

Case presentation

A 48-year-old male with a sacral chordoma underwent partial sacrectomy followed by post-operative radiotherapy. Upon recurrence he received palliative radiotherapy to hemipelvis and was offered therapy with imatinib. However, the disease was refractory to imatinib and he was started on treatment with erlotinib—showing a partial response on imaging at two months. He is currently doing well at 13 months since start of erlotinib.

Conclusions

As seen in previously reported cases, erlotinib is a therapeutic option in advanced chordoma, even in imatinib refractory cases and thus warrants exploration of its therapeutic role in prospective clinical trials.

Surgical management of chordoma: A systematic review

Context: Chordomas are rare primary tumors of bone characterized by local aggressiveness and poor prognosis. The surgical exeresis plays a critical role for their management. Objective: The aim was to provide an overview of the surgical management of chordomas of the mobile spine and sacrum, describing the most common surgical approaches, the role of surgical margins, the difficulties of en block resection, the outcomes of surgery, the recurrence rate and the use of associated therapies. Methods: We performed a systematic search using the keywords "chordoma" in combination with "surgery", "spine", "sacrum" and "radiotherapy". Results: Fifty-eight studies, describing 1359 patients with diagnosis of chordoma were retrieved. 17 studies were performed on subjects with cervical chordomas and 49 focused on patients with sacrococcygeal chordomas. The remaining studies included patients with chordomas in cranial region and/or mobile spine and/or sacroccygeal region. The recurrence rate ranged from 25% to 60% for cervical chordomas, and from 18% to 89% for sacrococcygeal chordomas. Conclusion: Despite the remarkable advances in the local management of chordoma performed in the last decades, the current results of surgery alone are still unsatisfactory. The radical en bloc excision of tumour is technically demanding, particularly in the cervical spine. Although radical surgery must still be considered the gold standard for the management of chordomas, a multidisciplinary approach is required to improve the local control of the disease in patients who undergo both radical and non-radical surgery. Adjuvant radiation therapy increases the continuous disease-free survival and the local recurrence-free survival. Level of evidence: Systematic review; level III.

Rehabilitation to Improve the Function and Quality of Life of Soft Tissue and Bony Sarcoma Patients

Sarcomas are bone and soft tissue tumors that can have significant effects on patient function and quality of life. Like most malignancies, treatment includes a combination of chemotherapy, radiation, and surgical resection, all of which also carry risks and long-term effects. A multidisciplinary rehabilitation plan can help minimize symptoms and sequelae which negatively affect the patient function and quality of life, including pain, chemotherapy-induced peripheral neuropathy, radiation fibrosis, activity restrictions following surgical excision, amputation, bowel and bladder dysfunction, and lymphedema. Patients should be evaluated by a rehabilitation specialist at any point during their diagnosis, treatment, and survivorship phase to determine appropriate interventions to minimize the impact of sarcomas and their treatment on patient function and quality of life.

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.

Spontaneous regression of a clival chordoma. Case report

In this case report, we present a rare and previously unreported case of spontaneous regression of a histologically consistent clival chordoma. At the time of diagnosis, imaging demonstrated a T2 hyperintense and T1 isointense midline skull base mass, centered in the nasopharynx, with scalloping of the ventral clivus consistent with a chordoma measuring 3.1 × 1.9 × 3.0 cm (8.84 cm³). On pre-operative imaging 2 months later, with no intervening therapy, the mass had regressed by 61.7% to a size of 2.3 × 2.1 × 1.4 cm (3.38 cm³). The patient self-administered several herbal supplements and animal oils which may have contributed to tumor regression. The purpose of this report is to document this rare occurrence and provide a comprehensive description of the case details and list of the various medications, herbs, and supplements used prior to this rare event.

Knockdown of cytokeratin 8 overcomes chemoresistance of chordoma cells by aggravating endoplasmic reticulum stress through PERK/eIF2α arm of unfolded protein response and blocking autophagy

Chordoma is a malignant primary osseous spinal tumor with pronounced chemoresistance. However, the mechanisms of how chordoma cells develop chemoresistance are still not fully understood. Cytokeratin 8 (KRT8) is a molecular marker of notochordal cells, from which chordoma cells were believed to be originated. In this study, we showed that either doxorubicin or irinotecan promoted KRT8 expression in both CM319 and UCH1 cell lines, accompanied by an increased unfolded protein response and autophagy activity. Then, siRNA-mediated knockdown of KRT8 chemosensitized chordoma cells in vitro. Mechanistic studies showed that knockdown of KRT8 followed by chemotherapy aggravated endoplasmic reticulum stress through PERK/eIF2α arm of unfolded protein response and blocked late-stage autophagy. Moreover, suppression of the PERK/eIF2α arm of unfolded protein response using PERK inhibitor GSK2606414 partially rescued the apoptotic chordoma cells but did not reverse the blockage of the autophagy flux. Finally, tumor xenograft model further confirmed the chemosensitizing effects of siKRT8. This study represents the first systematic investigation into the role of KRT8 in chemoresistance of chordoma and our results highlight a possible strategy of targeting KRT8 to overcome chordoma chemoresistance.

The extended posterior approach for resection of sacral tumours

PURPOSE

The conventional posterior approach is mostly advocated for excision of sacral tumours below S2. We describe an operative technique of single-stage en bloc resection of sacral tumours, extending up to S1, through an extended posterior approach.

METHOD

Nine patients, who had undergone resection of sacral tumours, by the described technique formed the basis of this study. Four patients had chordomas, whereas schwannoma, neurilemmoma, giant-cell tumour, malignant paraganglioma and recurrent Ewing's sarcoma were seen in one patient each. They were followed up at regular intervals with a mean follow-up of 45.4 months. Perioperative complications, their functional and oncological outcomes at final follow-up were analysed.

RESULT

None of the patients had any perioperative complications like uncontrolled haemorrhage, injury to the rectum, deep vein thrombosis or pulmonary embolism. One patient had a superficial wound infection which subsided with regular dressing, and another patient developed a wound breakdown that required an additional flap procedure. At final follow-up, six patients were able to walk without any assistive devices, six patients had normal bladder function, and five patients had normal bowel function. Five patients did not have any recurrence at final follow-up, whereas two were alive with the disease and two had died.

CONCLUSION

The reported technique allows en bloc resection of sacral tumours up to S1, through a posterior-only approach. It is less invasive with minimal morbidity. The functional and oncological outcomes are similar to those reported by other investigators. These slides can be retrieved from electronic supplementary material.

Management of Sacrococcygeal Chordoma: A Systematic Review and Meta-analysis of Observational Studies

STUDY DESIGN

Systematic review and meta-analysis of observational studies.

OBJECTIVE

The aim of the study is to evaluate different treatment modalities in the management of sacrococcygeal chordoma.

SUMMARY OF BACKGROUND DATA

Chordomas are primary malignant bone tumors associated with considerable morbidity and mortality.

METHODS

We searched MEDLINE, EMBASE, Cochrane Central-Register of Controlled Trials, and Scopus from inception to July 2015. Eligible studies included patients with sacrococcygeal chordoma treated exclusively with surgery, radiotherapy, or both. Two reviewers independently assessed the eligibility of potential studies, risk of bias, and extracted data. Outcomes of interest were all-cause mortality, progression-free survival, and metastases. We analyzed further surgical outcomes by resection margin. All outcomes were assessed at 60 months and more than 60 months following intervention.

RESULTS

We included 33 noncomparative studies reporting on 501 patients (mean age 57 years). Overall mortality rate was (16%) after surgical resection with adjuvant radiotherapy and (28%) after surgical resection, and (43%) after radiotherapy (P = 0.28). All-cause mortality following wide surgical resection was (32%) compared to (40%) after marginal resection (P = 0.51). Overall progression-free survival rate was (58%) after surgical resection with adjuvant radiotherapy and (55%) after surgery (P = 0.92). However, at more than 60 months follow-up, progression-free survival rates were significantly higher (P = 0.024) following surgical resection with adjuvant radiotherapy (74%) in comparison to surgery (55%) and radiotherapy (36%). Overall progression-free survival rates were nonsignificantly higher after wide surgical resection (66%) than marginal resection (33%) (P = 0.16). However, at 60 months follow-up, progression-free survival rates were significantly higher following wide surgical resection (73%) than marginal resection (33%) (P = 0.047).

CONCLUSION

Sacrococcygeal chordoma is a difficult to treat disease entity. Until comparative studies become available, wide surgical resection and multidisciplinary management are the recommended approaches to improve patient outcomes.

LEVEL OF EVIDENCE

3.

Clival chordoma: long-term clinical outcome in a single center

The treatment of clival chordoma remains highly challenging. This difficulty is enhanced by the very small likelihood of a successful complete surgical resection or nonsurgical treatment of chordoma. Additionally, no effective means of interdisciplinary treatment for chordoma have been identified. With this background, we analyzed data of patients who underwent multidisciplinary treatment for clival chordoma at our institution during the last 25 years.This retrospective study evaluated patients treated at a single center from 1992 to 2017.During the study period, 24 patients underwent 24 surgeries. Twenty-two surgical resections (including 1 initial surgery and 1 surgery for recurrence) were deemed maximally safe cyto-reductive resections (92%); the remaining 2 surgeries were deemed incomplete (8%), which were histologically confirmed in all but in 1 case (which involved radionecrosis). The complications were divided into endocrinologic, neurologic, and other complications. In 1 case (4%), surgery led to immediate dyspnea followed by death on the following day; in another case (4%), ischemic infarction led to sudden death. In 3 cases (13%), patients exhibited improvements of neurologic (visual or oculomotor) deficits that had been observed prior to surgery. The following new postoperative neurologic deficits were observed: oculomotor deficits in 4 cases, dizziness in 2 cases, and cranial nerve-attributed dysphagia in 3 cases. About 19 patients underwent adjuvant postoperative radiotherapy following the initial surgery (dose: 54.5 Gy in all cases). The mean and median follow-up durations were 50 ± 53 and 48.5 months, respectively. A Kaplan-Meier analysis estimated a median survival duration of 50.2 months (95% confidence interval 27.9-72.4 months).These findings highlight the importance of interdisciplinary treatment strategies, particularly those combining maximally safe cyto-reductive tumor resection and adjusted radiotherapy and other treatment options, for patients with relatively good conditions.

Clinicopathologic characteristics of poorly differentiated chordoma

Chordoma is a rare malignant tumor of bone with high morbidity and mortality. Recently, aggressive pediatric poorly differentiated chordoma with SMARCB1 loss has been described. This study summarizes the clinicopathologic features of poorly differentiated chordoma with SMARCB1 loss in the largest series to date. A search of records between 1990-2017 at MGH identified 19 patients with poorly differentiated chordoma. Immunohistochemical stains were evaluated. Kaplan-Meier survival statistics and log-rank (Mantel Cox) tests compared survival with other subtypes. The patients (n = 19) were diagnosed at a median age of 11 years (range: 1-29). Tumors arose in the skull base and clivus (n = 10/19; 53%); cervical spine (n = 6/19; 32%); and sacrum or coccyx (n = 3/19; 16%). The clinical stage of these patients (AJCC 7e) was stage 2A (n = 7/16; 44%); stage 2B (n = 6/16; 38%); stage 4A (n = 1/16; 6%); and stage 4B (n = 2/16; 13%). The tumors were composed of sheets of epithelioid cells with nuclear pleomorphism, abundant eosinophilic cytoplasm, and increased mitoses. Tumors were positive for cytokeratin (n = 18/18; 100%) and brachyury (n = 18/18; 100%). Patients were treated with a combination of excision, radiation therapy, and chemotherapy. No difference in overall survival, progression free survival, local control time, and metastasis free survival was identified between poorly differentiated chordoma of the skull base and of the spine. Compared to other chordoma subtypes, poorly differentiated chordoma has a significantly decreased mean overall survival after stratification by site (p = 0.037). Pediatric poorly differentiated chordoma has a distinct clinical and immunohistochemical profile, with characteristic SMARCB1 loss and decreased survival compared to conventional/chondroid chordoma. Recognition of this subtype is important because these malignancies should be treated aggressively with multimodality therapy.

Prognostic Factors in Patients With Spinal Chordoma: An Integrative Analysis of 682 Patients

BACKGROUND

The low incidence of spinal chordoma precludes a prospective study of prognostic factors with a large patient cohort.

OBJECTIVE

To perform a comprehensive integrative analysis on the prognostic factors, treatment, and outcomes of patients with spinal chordoma using data from 2 institutions and the literature.

METHODS

Appropriate studies were identified per search criteria. The local database was retrospectively searched to include a similar patient cohort.

RESULTS

Overall, 108 studies from the literature and 30 patients from our local institution were identified, resulting in a total of 682 patients. The median age was 57 years old and 35.2% were female. The median follow-up was 46 months (range: 1-408). The median progression-free survival (PFS) and overall survival (OS) were 72 months and 115 months, respectively. Significant prognostic factors for PFS on multivariate analysis included age (pediatric vs adult, hazard ratio [HR]: 2.00-14.36), tumor location (mobile spine vs sacral spine, HR: 0.31-0.87), pathology (differentiated vs classic, HR: 2.48-10.90),and chemotherapy (HR:1.11-3.85). Significant prognostic factors for OS on multivariate analysis included age (geriatric vs adult, HR: 1.52-3.45 and pediatric vs adult, HR: 1.73-9.36), bladder or bowel dysfunction (HR: 1.27-5.43), pathology (dedifferentiated vs classic, HR: 2.38-11.09), recurrence or progression (HR: 1.72-4.48), and metastases (HR: 1.11-2.47).

CONCLUSION

In patients with spinal chordoma, young age, location in sacral spine, dedifferentiated pathology, and chemotherapy were negative predictors of PFS, while young and old age, bladder or bowel dysfunction at presentation, dedifferentiated pathology, recurrence or progression, and metastases portended a worse OS.

Lymphocyte-Related Inflammation and Immune-Based Scores Predict Prognosis of Chordoma Patients After Radical Resection

The inflammatory microenvironment plays a critical role in the development and progression of malignancies. In the present study, we aimed to evaluate the prognostic value of lymphocyte-related inflammation and immune-based prognostic scores in patients with chordoma after radical resection, including the neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), monocyte-lymphocyte ratio (MLR), and systemic immune-inflammation index (SII). A total of 172 consecutive patients with chordoma who underwent radical resection were reviewed. R software was used to randomly select 86 chordoma patients as a training set and 86 chordoma patients as a validation set. Potential prognostic factors were also identified, including age, sex, tumor localization, KPS, Enneking stage, tumor size, and tumor metastasis. Overall survival (OS) was calculated using the Kaplan–Meier method and multivariate Cox regression analyses. NLR, PLR, SII, Enneking stage, tumor differentiation and tumor metastasis were identified as significant factors from the univariate analysis in both the training and validation sets and were subjected to multivariate Cox proportional hazards analysis. The univariate analysis showed that NLR ≥1.65, PLR ≥121, and SII ≥370×10⁹/L were significantly associated with poor OS. In the multivariate Cox proportional hazard analysis, SII, Enneking stage and tumor metastasis were significantly associated with OS. As noninvasive, low-cost, reproducible prognostic biomarkers, NLR, PLR and SII could help predict poor prognosis in patients with chordoma after radical resection. This finding may contribute to the development of more effective tailored therapy according to the characteristics of individual tumors.

Managing bowel and bladder impairments in sacral chordoma patients: a case-based approach

Introduction

Chordomas are primary bone tumors that occur in the axial spine and most commonly in the sacrum. Because of their location, chordomas can affect bowel and bladder continence resulting in either an upper or a lower motor neuron functional pattern.

Case presentation

We present two cases describing chordoma's impact on bowel and bladder function and the management plan used for improvement.

Discussion

The accurate identification of an upper or lower motor neuron pattern in the setting of chordoma aims to significantly improve management of bowel and bladder impairment.

Clival chordoma: a single-centre outcome analysis

BACKGROUND

The treatment of clival chordomas remains challenging. Total tumour resection is often impossible without hampering adjacent anatomical structures and causing functional sequelae. On the other hand, chordomas show limited response to non-surgical treatment modalities. Up to now, no well-established interdisciplinary treatment algorithms for clival chordomas exist. In this regard, we analysed the data from all patients that underwent interdisciplinary treatment for clival chordoma in our institution over the last 10 years.

METHOD

Retrospective report of all patients treated at the authors' institution from 2005 to 2015.

RESULTS

Thirteen patients underwent 24 surgeries, of which 2 (8%) were gross total resections and 22 (92%) incomplete resections. Neurological deterioration, endocrinological disturbances and other surgical complications were observed in six (25%), three (13%) and nine (38%) cases, respectively. Three surgeries (13%) led to an improvement of the initial preoperative neurological condition. All patients were discussed on the interdisciplinary tumour board and all underwent one type of radiotherapy following initial surgery: proton beam in 11 cases (85%) and photon beam in two (15%) cases. In the course of their recurrent disease, three patients (23%) received systemic therapy (imatinib, pazopanib and nivolumab). One patient received a personalised cellular immunotherapy. One patient (8%) was lost to follow-up. Of the remaining 12 patients, four patients (33%) died in the period of analysis; all deaths were chordoma-related. The 5-year cumulative survival rate was 83% (52-97%, CI 95%), 5-year progression-free survival rate was 53% (26-79%, CI 95%). The eight patients (66%) still alive had favourable outcome (KPS, 90 ± 10.7%). SF36 analysis among the survivors revealed 43 points for the Physical Component Summary (12% above, 38% at and 50% below the general population norm) and 47 points for the Mental Component Summary (25% above, 38% at and 38% below).

CONCLUSIONS

Our patients show a low rate of gross total resection but an outcome well comparable to other published results. This emphasises the importance of interdispiplinary treatment strategies, with surgery supplying maximal safe resection and avoiding severe neurological deficit, allowing patients to undergo adjusted radiotherapy and other treatment options in a good condition.

High expression of Sam68 in sacral chordomas is associated with worse clinical outcomes

Src-associated in mitosis of 68 kDa (Sam68), also known as KHDRBS1 (KH domain-containing, RNA-binding, signal transduction-associated 1), is a member of the signal transduction and activation of RNA family. Previous studies have demonstrated that the aberrant expression of Sam68 is associated with the progression and prognosis of a variety of cancers, but little is known about its expression and role in chordomas, which are rare and aggressive bone neoplasms. In this study, we analyzed 40 tumor tissues and 20 distant normal tissues obtained from 40 patients with sacral chordoma using immunohistochemistry, and observed the expression of Sam68 was significantly upregulated in sacral chordomas compared with normal tissues (P=0.001). A positive correlation between the expression of Sam68 and the cell proliferation index Ki-67 was determined using Spearman’s rank correlation test (γ =0.599, P<0.001). In addition, high expression of Sam68 was significantly associated with surrounding muscle invasion (P<0.001). Moreover, Kaplan–Meier curves showed that patients with overexpressed Sam68 had shorter local recurrence-free survival time (P<0.001). Lastly, multivariate analysis indicated that Sam68 is an independent prognostic factor for the local recurrence-free survival of sacral chordomas (hazard ratio =5.929, 95% CI: 1.092–32.188, P=0.039). Our findings suggest the use of Sam68 as a predictor for the recurrence of sacral chordomas.

Immunotherapy as a Potential Treatment for Chordoma: a Review

Chordoma is a locally aggressive primary malignancy of the axial skeleton. The gold standard for treatment is en bloc resection, with some centers now advocating for the use of radiation to help mitigate the risk of recurrence. Local recurrence is common, and salvaging local failures is quite difficult. Chemotherapy has been ineffective and small molecule targeted therapy has had only marginal benefits in small subsets of patients with rare tumor phenotypes or refractory disease. Recent successes utilizing immunotherapy in a variety of cancers has led to a resurgence of interest in modifying the host immune system to develop new ways to treat tumors. This review will discuss these studies and will highlight the early studies employing immune strategies for the treatment of chordoma.

Expression of far upstream element-binding protein 1 correlates with c-Myc expression in sacral chordomas and is associated with tumor progression and poor prognosis

The far upstream element (FUSE)-binding protein 1 (FUBP1), a well-known transcriptional regulator of the proto-oncogene c-Myc, has been demonstrated by previous work to be aberrantly expressed in a variety of tumors and plays a critical role in tumor progression; however, its expression and function in relatively rare and aggressive chordomas remains unclear. In this retrospective study, we reviewed clinicopathologic characteristics of 40 patients diagnosed with sacral chordoma, and analyzed 40 tumor and 20 distant normal tissues obtained from patients during the primary surgical tumor excision. Using immunohistochemistry, we observed an up-regulation in the expression of FUBP1 and c-Myc in sacral chordomas compared with the normal tissues (P = 0.001 for both). Additionally, positive correlations of FUBP1 expression with c-Myc (γ = 0.651, P < 0.001) and the cell proliferation index Ki-67 expression (γ = 0.447, P = 0.004) were indicated using Spearman's rank correlation coefficient. Increased expression of FUBP1 was significantly associated with tumor invasion into the surrounding muscles (P = 0.002). Kaplan-Meier curves demonstrated the association between FUBP1 levels and the patients' local recurrence-free survival (LRFS) (P < 0.001) but not with the overall survival (OS) (P = 0.070). The independent prognostic significance of FUBP1 levels for the LRFS was indicated by multivariate analysis (HR = 4.272; 95% CI, 1.133-16.112; P = 0.032). Our findings demonstrate an association between FUBP1 levels and chordoma progression and prognosis, suggesting that FUBP1 can be used as a biomarker and a potential therapeutic target.

Medical treatment of advanced chordomas

Chordoma is a very rare bone sarcoma that can arise from any site along the spine and from the skull base. En bloc resection is the gold standard for treatment while radiation therapy has been shown to provide both curative and palliative benefit. Unfortunately, local recurrences are common, even after a complete surgical resection, and up to 40% of patients suffer from distant metastases, while salvage treatments are challenging. Patients carrying an advanced disease need a systemic treatment. Unluckily, conventional chordoma are insensitive to cytotoxic chemotherapy that is considered the standard treatment option in patients with metastatic sarcoma. In the last decade, innovative therapies have been introduced, positively impacting disease control and patients' quality of life. In addition, a better understanding of the molecular characteristics of chordoma allowed to detect new potential targets. This review is focused on the pharmacological management of patients affected by an advanced disease, starting with a summary of data available on conventional chemotherapy, then moving to a deeper analysis of available data on molecular agents and immunotherapy, and finally providing an update on ongoing clinical trials and future prospective.

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.

Prognostic Factors and Survival Outcome in Patients with Chordoma in the United States: A Population-Based Analysis

OBJECTIVE

To evaluate prognostic factors of patients with chordoma through a population-based analysis.

METHODS

Surveillance, Epidemiology, and End Results (SEER) database was queried for patients with chordoma from 1973 to 2013. Kaplan-Meier univariate analysis and Cox regression multivariate analysis were performed to examine prognostic factors in overall survival (OS) and disease-specific survival (DSS).

RESULTS

One thousand five hundred ninety-eight patients with chordoma are identified. Kaplan-Meier analysis showed that OS and DSS were 61% and 71% at 5 years and 41% and 57% at 10 years. Multivariate Cox regression analysis demonstrated that independent predictors of OS and DSS are age at diagnosis (hazard ratio [HR]= 2.80 [95% confidence interval {CI}, 2.12-3.70], P < 0.001; HR = 1.60 [95% CI, 1.18-2.16], P = 0.002), surgical treatment (HR = 0.62 [95% CI, 0.52-0.73], P < 0.001; HR = 0.64 [95% CI, 0.52-0.79], P < 0.001), radiation therapy (HR = 1.23 [95% CI, 1.07-1.42], P = 0.004; HR = 1.29 [95% CI, 1.09-1.54], P = 0.004), tumor size (HR = 1.53 [95% CI, 1.32-1.78], P < 0.001; HR = 1.62 [95% CI, 1.35-1.94], P < 0.001) and distant metastasis (HR = 3.40 [95% CI, 2.45-4.71], P < 0.001; HR = 3.77 [95% CI, 2.61-5.45], P < 0.001).

CONCLUSION

We report the largest study to date to evaluate prognostic factors of patients with chordoma. Multivariate analysis demonstrated that older age, greater tumor size, and distant metastasis were correlated with decreased survival, whereas surgical resection was correlated with increased survival. Patients receiving radiation therapy also showed decreased survival, likely an indication of the patients' advanced stage of disease, making them poor surgical candidates.

Image-guided resection of aggressive sacral tumors

OBJECTIVE The aim of this study was to identify and discuss operative nuances utilizing image guidance in the surgical management of aggressive sacral tumors. METHODS The authors report on their single-institution, multi-surgeon, retrospective case series involving patients with pathology-proven aggressive sacral tumors treated between 2009 and 2016. They also reviewed the literature to identify articles related to aggressive sacral tumors, their diagnosis, and their surgical treatment and discuss the results together with their own experience. Information, including background, imaging, treatment, and surgical pearls, is organized by tumor type. RESULTS Review of the institutional records identified 6 patients with sacral tumors who underwent surgery between 2009 and 2016. All 6 patients were treated with image-guided surgery using cone-beam CT technology (O-arm). The surgical technique used is described in detail, and 2 illustrative cases are presented. From the literature, the authors compiled information about chordomas, chondrosarcomas, giant cell tumors, and osteosarcomas and organized it by tumor type, providing a detailed discussion of background, imaging, and treatment as well as surgical pearls for each tumor type. CONCLUSIONS Aggressive sacral tumors can be an extremely difficult challenge for both the patient and the treating physician. The selected surgical intervention varies depending on the type of tumor, size, and location. Surgery can have profound risks including neural compression, lumbopelvic instability, and suboptimal oncological resection. Focusing on the operative nuances for each type can help prevent many of these complications. Anecdotal evidence is provided that utilization of image-guided surgery to aid in tumor resection at our institution has helped reduce blood loss and the local recurrence rate while preserving function in both malignant and aggressive benign tumors affecting the sacrum.

IMAGING DIAGNOSIS-MAGNETIC RESONANCE IMAGING AND HISTOPATHOLOGICAL FEATURES OF A SKULL BASE CHORDOMA IN A CAT

An 8-year-old domestic short-haired cat was presented with anorexia, lethargy, ataxia and one episode of consciousness loss. A midline vertically orientated, biconcave, extra-axial mass originating from the basioccipital bone was detected on magnetic resonance images of the head. The mass was T1W iso- to hypointense when compared with normal grey matter, T2W hyperintense with small areas of isointensity and heterogeneously enhanced with contrast. Multiple signal voids were observed on T2^* images. Histopathological evaluation confirmed a chordoma. To the authors' knowledge this is the first report of the imaging characteristics of a chordoma affecting the skull base in a cat.

Systemic therapy for selected skull base sarcomas: Chondrosarcoma, chordoma, giant cell tumour and solitary fibrous tumour/hemangiopericytoma

This review highlights the data currently available on the activity of systemic therapy in chondrosarcoma, chordoma, giant cell tumour of the bone (GCTB) and solitary fibrous tumour, i.e., four rare sarcomas amongst mesenchymal malignancy arising from the skull base.

Expression of programmed death-1 ligand (PD-L1) in tumor-infiltrating lymphocytes is associated with favorable spinal chordoma prognosis

Aberrant expression of programmed death-1 (PD-1) receptor/PD-1 ligand (PD-L1) proteins alters human immunoresponse and promotes tumor development and progression. We assessed the expression status of PD-1 and PD-L1 in spinal chordoma tissue specimens and their association with clinicopathological characteristics of patients. Formalin-fixed paraffin-embedded tumor samples from 54 patients with spinal chordoma were collected for immunohistochemical analysis of PD-1 and PD-L1 expression. The association of the expression levels of PD-1 and PD-L1 with clinicopathological variables and survival data were statistically analyzed. Lymphocyte infiltrates were present in all 54 patient samples. Of 54 samples, 37 (68.5%) had both positive PD-1 and PD-L1 expression in tumor cell membrane. Moreover, 38 (70.4%) and 12 (22.2%) had positive PD-1 and PD-L1 expression in tumor-infiltrating lymphocytes (TILs), respectively. Tumors with positive PD-L1 expression were significantly associated with advanced stages of chordoma (p = 0.041) and TIL infiltration (p = 0.005), and had a borderline association with tumor grade (p = 0.051). However, positive tumor PD-L1 expression was not significantly associated with local recurrence-free survival (LRFS) or overall survival (OS). PD-1 expression in TILs was associated with poor LRFS (χ(2) = 10.051, p = 0.002, log-rank test). Multivariate analysis showed that PD-L1 expression only in TILs was an independent predictor for LRFS (HR = 0.298, 95% CI: 0.098-0.907, p = 0.033), and OS (HR = 0.188, 95% CI: 0.051-0.687, p = 0.011) in spinal chordoma patients. In conclusion, PD-L1 expression in TILs was an independent predictor for both LRFS and OS in spinal chordoma patients. Our findings suggest that the PD-1/PD-L1 pathway may be a novel therapeutic target for the immunotherapy of chordoma.

Contemporary management of clival chordomas

PURPOSE OF REVIEW

Clival chordomas are rare malignant tumors associated with a poor prognosis. In this article, we review the current literature to identify a variety of strategies that provide guidelines toward the optimal management for this aggressive tumor.

RECENT FINDINGS

Molecular disease, particularly, the development of characterized chordoma cell lines, has become one of the new cornerstones for the histological diagnosis of chordomas and for the development of effective chemotherapeutic agents against this tumor. Brachyury, a transcription factor in notochord development, seems to provide an excellent diagnostic marker for chordoma and may also prove to be a valuable target for chordoma therapy. Aggressive cytoreductive surgery aiming for gross total resection with maintenance of key neurovascular structures, followed by proton beam or hadron radiation, provides the best local recurrence and overall survival rates.

SUMMARY

Clival chordomas are locally aggressive tumors that are challenging to treat because of their unique biology, proximity to key neurovascular structures and poor prognosis. Currently, chordomas are optimally managed with aggressive surgery, whilst preserving key structures, and postoperative radiation in a multidisciplinary setting with an experienced team. The advancement of molecular techniques offers exciting future diagnostic and therapeutic options in the management of chordomas.

Surgical treatment of sacral chordoma: survival and prognostic factors

INTRODUCTION

Sacral chordoma is a rare low-to-intermediate grade malignant tumour. The mainstay of treatment is still surgery with en bloc and wide resection margins, which can grant the best chances of a long-term control or cure of this disease. The first aim of this paper is to collect data about survival, time to local recurrence and metastasis among patients affected by sacral chordoma and primarily treated with surgery. The second aim is to analyze the influence of level resection, tumor volume and surgical margins on local recurrence.

MATERIALS AND METHODS

The study population was composed of 14 patients treated with sacral chordoma resection at the National Tumour Institute of Naples-Pascale (Italy) from January 2000 to June 2013. The median follow-up was 84 months (range 24-132 months). The follow-up was characterized by: standard radiographs, MRI, and a CT scan of the chest annually. Time to recurrence or metastasis was calculated from the date of resection to the date of diagnosis of first recurrence or metastasis.

RESULTS

Out of all the patients, six died (42.86 %) during the follow-up; 6 (42.86 %) had local recurrence; 4 (28.57 %) had metastasis. At univariate analysis wide surgical margins (R0) were associated with increased survival up to a local recurrence (OR = 0.0286; 95 % CI = 0.0014-0.5739; P = 0.026); the level of resection (OR = 3.33; 95 % CI = 0.3619-30.7025; P = 0.592) and tumour volume (P = 1) did not show a statistically significant correlation.

DISCUSSION

Based on our experience, we hope all patients to be treated by surgery, the only good standard treatment of this disease. The resection should result in margins as wide as possible. For these reasons, it is essential for this disease to be treated in highly specialized centres because only a complete surgery can offer a chance to care for these patients.

CONCLUSIONS

Solid survival at long-term follow-up can be achieved by a surgical resection performed with wide margins.

Prognostic factors in spinal chordoma: A systematic review

OBJECTIVE

Discovering reliable prognostic factors for spinal chordoma remains a challenge. We attempted to identify evidence-based prognostic factors in the literature since its inception and to establish pooled relative risks (RR) of such factors.

METHODS

MEDLINE and Embase search (inception to December 2014). Two reviewers independently selected papers involving spinal chordoma prognostic factors, and studied them for methodological quality and valuable new factors. Subsequently, we attempted to pool the results.

RESULTS

Of 1465 citations, we studied 65 papers closely, and found several "new" prognostic factors. However, only eight papers were of adequate quality for analysis. Location in the upper cervical spine (pooled RR=5.46, 95% confidence interval [CI]: 2.23-13.34), worse preoperative Frankel score (pooled RR=2.77, 95% CI: 1.73-4.42), intralesional surgery (pooled RR=2.68, 95% CI: 1.66-4.32), greater extent of invasion (pooled RR=5.09, 95% CI: 1.49-17.41), and revision surgery (pooled RR=2.42, 95% CI: 1.34-4.36) appeared to be independent factors for worse outcome.

CONCLUSIONS

Despite the wealth of literature available, disappointingly few papers are of sufficient quality for drawing valid conclusions related to spinal chordoma prognostic factors. The heterogeneity of the studies renders results pooling almost impossible. More accurate individual prognostication requires methodologically high-quality studies with more uniform study design and data reporting.

Prognostic Factors in the Operative Management of Sacral Chordomas

OBJECTIVE

Surgical resection of sacral chordomas offers the best long-term prognosis but has high rates of local recurrence, metastases, and mortality. Most prognostic studies are limited by low patient numbers, variation in treatment, follow-up, and prognostic variables studied. The objective of this study was to identify factors associated with recurrence, metastasis, and survival.

METHODS

Retrospective review of 58 patients undergoing sacrectomy for chordoma with a mean age of 63 years (range: 41-80 years) and a mean follow-up of 45.3 months (range: 2-144 months). Data on prognostic variables and outcomes were collected. Forty-two patients underwent a combined anterior and posterior approach and 16 underwent a posterior-only approach.

RESULTS

Twenty-six patients (44.8%) died during follow-up. Kaplan-Meier estimates for 5- and 10-year survival were 62% and 26%, respectively. Local recurrence occurred in 32 patients (51.7%) and metastases in 19 (32.7%). Adequacy of resection margins was the most important predictor of disease recurrence, metastases, and survival. Tumors >8 cm were associated with significantly increased risk of metastases and reduced survival (P < 0.05). Dedifferentiated disease and infiltration of the sacroiliac joints and/or adjacent musculature were also associated with reduced survival. Median survival was 23 months for patients with gluteus maximus invasion, 66 months for gluteus maximus and piriformis invasion, 67 months for piriformis invasion, and 90 months for patients with no muscle invasion.

CONCLUSIONS

Patients with inadequate resection margins, tumors >8 cm, sacroiliac joint and/or musculature infiltration, and dedifferentiated disease have significantly worse oncologic outcomes. Involvement of gluteus maximus alone confers a higher risk of metastases and local recurrence than involvement of piriformis and gluteus maximus, or piriformis alone.

A new type of reconstruction of the hemipelvis after Type 3 amputative sacrectomy using pedicled fibula

This is a technical note of pelvic reconstruction performed by an advanced multidisciplinary team. The authors report a new 3-stage reconstruction of the hemipelvis after Type 3 sacrectomy involving instrumented spinoiliac arthrodesis and pedicled fibula grafting in 2 patients.

The anterior stage of the procedure begins with a transabdominal approach to mobilize the viscera and to free up the tumor from the vessels. The posterior divisions of internal iliac vessels, the middle sacral vessels, and the lateral sacral vessels are then ligated. An anterior vertebrectomy is done at the appropriate level, followed by an anterior osteotomy through the lateral planed surgical margin of the sacrum close to the salvaged sacroiliac joint. The second stage includes a major sacral resection with lower-extremity amputation from the pubic symphysis through the intact side of the sacrum, ipsilateral pedicled fibula harvesting, and closure with an ipsilateral pedicled quadriceps flap. The final stage involves reconstruction with lumboiliac instrumentation. The pedicled fibular graft left from the second stage is then placed distally within the previously created iliopectineal docking site and proximally within the L-5 docking site.

The authors believe that this is a feasible and reproducible technique with theoretical advantages that have to be proved in the long-term follow-up.

Natural history and surgical treatment of chordoma: a retrospective cohort study

CONTEXT AND OBJECTIVE

Chordoma is a rare tumor with a high risk of locoregional recurrences. The aim of this study was analyze the long-term results from treating this pathological condition.

DESIGN AND SETTING

Cohort study in a single hospital in São Paulo, Brazil.

METHODS

This was a retrospective cohort study on 42 patients with chordoma who were treated at Hospital A. C. Camargo between 1980 and 2006. The hospital records were reviewed and a descriptive analysis was performed on the clinical-pathological variables. Survival curves were estimated using the Kaplan-Meier method and these were compared using the log-rank test.

RESULTS

Nineteen patients were men and 23 were women. Twenty-five tumors (59.5%) were located in the sacrum, eleven (26.2%) in the skull base and six (14.3%) in the mobile spine. Surgery was performed on 28 patients (66.7%). The resection was considered to have negative margins in 14 cases and positive margins in 14 cases. The five-year overall survival (OS) was 45.4%. For surgical patients, the five-year OS was 64.3% (82.2% for negative margins and 51.9% for positive margins). In the inoperable group, OS was 37.7% at 24 months and 0% at five years.

CONCLUSION

Complete resection is related to local control and definitively has a positive impact on long-term survival.

Prognostic Factors in the Operative Management of Dedifferentiated Sacral Chordomas

BACKGROUND:

Dedifferentiated chordomas are rare high-grade malignant spinal tumors for which there is minimal information to help guide treatment.

OBJECTIVE:

To identify prognostic factors associated with increased risk of local recurrence, metastases, and reduced survival in a cohort of patients undergoing sacrectomy for de novo dedifferentiated sacral chordoma.

METHODS:

Ten patients undergoing sacrectomy for histologically confirmed dedifferentiated chordoma at a specialist center were reviewed. There were 6 male and 4 female patients with a mean age of 66.7 years (range, 57-80 years) and mean follow-up of 36.7 months (range, 3-98 months). Data on prognostic factors were collected.

RESULTS:

The commonest presenting symptom was lumbar/gluteal pain. Mean duration of preoperative symptoms was 3.6 months (range, 2-7 months). Local recurrence was seen in 7 patients; metastases occurred in 5 patients. After sacrectomy, 7 patients died at a mean of 41 months (range, 3-98 months). Tumor size &gt;10 cm in diameter, amount of dedifferentiation within the conventional chordoma, sacroiliac joint infiltration, and inadequate resection margins were associated with increased risk of recurrence and reduced survival. Surgical approach, cephalad extent of primary tumor, and adjuvant radiotherapy did not affect oncological outcomes.

CONCLUSION:

Dedifferentiated chordomas are aggressive malignant tumors with a higher risk of local recurrence, metastases, and early mortality than conventional chordomas. Tumor diameter &gt;10 cm, marginal resection, and sacroiliac joint infiltration may be associated with increased risk of local recurrence and mortality. Those with a smaller burden of dedifferentiated disease (&lt;1 cm2) within the primary chordoma have a better prognosis. Patients should be counseled about these risks before surgery and should have regular follow-up for the detection of local recurrence and metastases.

[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.

A review of the surgical management of sacral chordoma

BACKGROUND

Sacral chordomas are rare low-to-intermediate grade malignant tumours, which arise from remnants of the embryonic notochord. This review explores prognostic factors in the management of sacral chordomas and provides guidance on the optimal treatment regimens based on the current literature.

PATIENTS AND METHODS

Electronic searches were performed using MEDLINE, Embase and the Cochrane library to identify studies on prognostic factors in the management of sacral chordomas published between January 1970 and December 2013. The literature search and review process identified 100 articles that were included in the review article. This included both surgical and non-surgical studies on the management of sacral chordomas.

RESULTS

Sacrectomy with wide resection margins forms the mainstay of treatment but is associated with high risk of disease recurrence and reduced long-term survival. Adequate resection margins may require sacrifice of adjacent nerve roots, musculature and ligaments leading to functional compromise and mechanical instability. Large tumour size (greater than 5-10 cm in diameter), dedifferentiation and greater cephalad tumour extension are associated with increased risk of disease recurrence and reduced survival. Chordomas are poorly responsive to conventional radiotherapy and chemotherapy.

CONCLUSION

Operative resection with wide resection margins offers the best long-term prognosis. Inadequate resection margins, large tumour size, dedifferentiation, and greater cephalad chordoma extension are associated with poor oncological outcomes. Routine long-term follow-up is essential to enable early detection and treatment of recurrent disease.

An overview of the role of cancer stem cells in spine tumors with a special focus on chordoma

Primary malignant tumors of the spine are relatively rare, less than 5% of all spinal column tumors. However, these lesions are often among the most difficult to treat and encompass challenging pathologies such as chordoma and a variety of invasive sarcomas. The mechanisms of tumor recurrence after surgical intervention, as well as resistance to radiation and chemotherapy, remain a pervasive and costly problem. Recent evidence has emerged supporting the hypothesis that solid tumors contain a sub-population of cancer cells that possess characteristics normally associated with stem cells. Particularly, the potential for long-term proliferation appears to be restricted to subpopulations of cancer stem cells (CSCs) functionally defined by their capacity to self-renew and give rise to differentiated cells that phenotypically recapitulate the original tumor, thereby causing relapse and patient death. These cancer stem cells present a unique opportunity to better understand the biology of solid tumors in general, as well as targets for future therapeutics. The general objective of the current study is to discuss the fundamental concepts for understanding the role of CSCs with respect to chemoresistance, radioresistance, special cell surface markers, cancer recurrence and metastasis in tumors of the osseous spine. This discussion is followed by a specific review of what is known about the role of CSCs in chordoma, the most common primary malignant osseous tumor of the spine.

Long-term outcome following surgical treatment of sacral chordoma

BACKGROUND

Sixteen sacral chordoma surgeries performed at a single institution during the 1983-2008 period were retrospectively studied. Our aim is to assess surgical treatment and long-term outcomes.

METHODS

Fifteen patients underwent primary wide excision, and one intralesional excision using ethanol for local control and radiation therapy (RT). A combined anteroposterior approach for large tumors above S2, and wide excision was performed with the modified threadwire-saw (MT-saw) after 1997.

RESULTS

Fourteen of the 15 patients had wide margins, one a wide margin with contamination. The MT-saw was facilitated sacral excision with wide margins. Eleven patients are alive for 5-28 years. Five patients died before 10 years, two patients experienced sepsis, and one of another disease. Two patients died of local recurrence (LR) and another of multiple metastases after intralesional excision and wide excision with contamination, respectively. LR and complications occurred 4 each of 11 patients with tumors ≥ 10 cm, neither with tumors < 10 cm. The overall 5- and 10-year survival rate with wide surgical margins was 13/16 (81.3%) and 8/13 (61.5%).

CONCLUSIONS

A combined anteroposterior approach for large tumors, and the MT-saw facilitates sacral excision with wide margins. Wide excision is recommended for younger patients.

[Tumours of the upper cervical spine]

OBJECTIVE

Vertebral tumours arising in the upper cervical spine are rare. We present our experience in managing these neoplasms.

MATERIAL AND METHODS

We retrospectively reviewed the case histories of patients treated at our institution between January 2000 and June 2011.

RESULTS

There were 9 patients with tumours in C1-C2-C3: 2metastases, 3chordomas, 2plasmocytomas, 1chondrosarcoma and 1osteochondroma. All patients complained of neck pain at the time of diagnosis. Three patients underwent an anterior and posterior approach, 3 an exclusively posterior approach and 3 an exclusively anterior surgical approach. Tumour resection was intralesional in 7 cases. Chemo-radiotherapy was used as adjuvant therapy in patients with malignant tumours.

CONCLUSIONS

Vertebral tumours in the upper cervical spine are usually malignant. Achieving en bloc resection is particularly challenging and is technically unfeasible in many cases. This worsens the prognosis and makes adjuvant treatment very important.

Sacrococcygeal chordoma, a rare cause of coccygodynia

Patient: Male, 73

Final Diagnosis: Sacrococcygeal chordoma •

Symptoms: Coccycodynia • sacral pain

Medication: —

Clinical Procedure: —

Specialty: Surgery

Objective: Rare disease

Skull base chordomas: clinical features, prognostic factors, and therapeutics

Chordomas of the skull base are one of the rarest intracranial malignancies that arise from ectopic remnants of embryonal notochod. The proximity of many chordomas to neurovascular structures makes gross total resection difficult, and the tendency for recurrence leads to the routine use of adjuvant postoperative radiation. Several surgical approaches are used ranging from extensive craniotomies to minimally invasive endonasal endoscopic approaches. In this review, the histopathology and epidemiology, imaging characteristics, surgical approaches, adjuvant therapies, prognostic factors, and molecular biology of chordomas are described.

Three-level en bloc spondylectomy for chordoma

BACKGROUND

En bloc resection of spinal and sacral chordomas may convey a survival benefit. However, these procedures often are complex and require the surgeon to plan a procedure that results in negative tumor margins, protects vital neurovascular structures, and concludes with a viable biomechanical reconstruction.

OBJECTIVE

We present a case of a 3-level en bloc lumbar spondylectomy and reconstruction.

METHODS

A case of a 45-year-old woman with biopsy-proven exophytic L4 chordoma is presented. The patient underwent successful L3-L5 en bloc spondylectomy and reconstruction over 3 stages.

RESULTS

The patient did well following the procedure, and was neurologically intact at 6-week follow-up.

CONCLUSION

Three-level en bloc spondylectomy with lumbopelvic reconstruction is a challenging yet feasible procedure.