Review of current treatment of sacral chordoma

Latest Developments in Targeted Biological Therapies in the Management of Chordoma and Chondrosarcoma

STUDY DESIGN

Systematic review.

OBJECTIVES

The objective of this review paper was to summarize targeted molecular therapy options for spinal chordoma and chondrosarcoma, and to provide an update on the relevant clinical trials open for recruitment.

METHODS

A systematic review of the current literature was performed, according to PRISMA guidelines, to summarize the latest developments in non-surgical molecular treatment options for low grade malignant primary spinal tumours. We also summarize those actively recruiting clinical trials based on clinicaltrials.gov.

RESULTS

A total of 73 studies and completed clinical trials were reviewed. Twenty actively recruiting clinical trials (eight for chordoma and twelve for chondrosarcoma) were identified.

CONCLUSIONS

There is a strong need to find new therapeutic options to complement surgical resection and radiation therapy, which remain the cornerstone of management. Targeted therapies against molecular pathways show promise as compared to conventional chemotherapy.

Coccygeal tumours unveiled: a retrospective cohort analysis from a tertiary referral centre

BACKGROUND

Isolated tumours affecting the coccyx are infrequent, with only a handful of documented cases in the literature. Herein, we highlight the most extensive consecutive case series involving various isolated coccyx tumours with varied clinical presentations and imaging features.

METHODS

A retrospective search of our tertiary Orthopaedic oncology institute's oncology and Radiology database [Radiology Information System, Picture Archiving and Communication System, and Computerised Radiology Information System] for the keyword "Coccyx" and "Tumour" was performed over 15 years (between December 2007 and August 2022). Data collected was correlated with local histopathology and laboratory records. Patient demographics, clinical characteristics, and complementary imaging findings were recorded for analysis.

RESULTS

One hundred and three lesions originating in the coccyx with a mean age of 62 years (range 25-90 years) were identified. There was a male preponderance with 59 male and 44 female patients (1.3:1.0). The most typical tumour noted was chordoma. Other lesions included a dermoid cyst, a myxopapillary ependymoma, a notochordal remnant, an osteochondroma, an Ewing sarcoma, and a teratoma.

CONCLUSION

Our analysis suggests that most of the tumours involving coccyx are chordomas with a few rarely encountered benign and malignant tumours. Radiological imaging plays a vital role in characterising isolated tumours affecting the coccyx and guiding appropriate patient management.

ADVANCES IN KNOWLEDGE

This is the largest reported series of coccygeal tumours. Chordoma is the commonest coccygeal tumour. Patients with unexplained coccydynia should undergo detailed investigations, preferably with cross-sectional imaging.

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

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

Management of Chordoma of the Sacrum and Mobile Spine

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

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

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

Comparison of Wide Margin and Inadequate Margin for Recurrence in Sacral Chordoma: A Meta-Analysis

STUDY DESIGN

.: A meta-analysis.

OBJECTIVE

.: The goal of this study was to accurately evaluate the risk ratio (RR) of recurrence in chordoma patients with wide margin after removing the tumors using surgery, compared with inadequate margin (intralesional or marginal).

SUMMARY OF BACKGROUND DATA

.: As a rare malignant bone cancer, the more effective treatment for sacral chordoma is still surgical resection. However, there is no convincing evidence and risk ratio about sacral chordoma patients would be benefit from which kind of surgical margin.

METHODS

.: We searched the PubMed, Cochrane Library, Web of Science, and EMBASE from inception to December 2018. The heterogeneity analysis and calculation of the pooled risk ratio were performed using RevMan 5.3 software. The assessment of publication bias and sensitivity analysis was conducted using StataSE 15.1 software. The protocol for this meta-analysis was registered on International prospective register of systematic reviews (PROSPERO, CRD42019127441).

RESULTS

.: Twelve studies with a total of 436 patients who met the inclusion criteria were included. The pooled results indicated that patients in the wide group had lower recurrence rate than those in the inadequate group (RR = 0.42, 95% confidence interval [CI] 0.31-0.57; P < 0.001). And patients in the wide group had lower mortality rate than those in the inadequate group (RR = 0.49, 95% CI 0.26-0.91; P = 0.02). No significant differences in the risk of mortality were found between relapsed patients in the two groups (RR = 0.64, 95% CI 0.35-1.15; P = 0.13).

CONCLUSION

.: In sacral chordoma patients, wide margin is associated with low recurrence risk, when it is feasible, a wide excision should be considered appropriate for sacrum chordoma.

LEVEL OF EVIDENCE

2.

Active receptor tyrosine kinases, but not Brachyury, are sufficient to trigger chordoma in zebrafish

The aberrant activation of developmental processes triggers diverse cancer types. Chordoma is a rare, aggressive tumor arising from transformed notochord remnants. Several potentially oncogenic factors have been found to be deregulated in chordoma, yet causation remains uncertain. In particular, sustained expression of TBXT – encoding the notochord regulator protein brachyury – is hypothesized as a key driver of chordoma, yet experimental evidence is absent. Here, we employ a zebrafish chordoma model to identify the notochord-transforming potential of implicated genes in vivo. We find that Brachyury, including a form with augmented transcriptional activity, is insufficient to initiate notochord hyperplasia. In contrast, the chordoma-implicated receptor tyrosine kinases (RTKs) EGFR and Kdr/VEGFR2 are sufficient to transform notochord cells. Aberrant activation of RTK/Ras signaling attenuates processes required for notochord differentiation, including the unfolded protein response and endoplasmic reticulum stress pathways. Our results provide the first in vivo evidence against a tumor-initiating potential of Brachyury in the notochord, and imply activated RTK signaling as a possible initiating event in chordoma. Furthermore, our work points at modulating endoplasmic reticulum and protein stress pathways as possible therapeutic avenues against chordoma.

Summary: An injection-based chordoma model in zebrafish shows that the hypothesized chordoma oncogene brachyury is insufficient, whereas EGFR and VEGFR2 are sufficient, to trigger notochord hyperplasia in our model.

Risk Factors Associated with Reconstructive Complications Following Sacrectomy

BACKGROUND

Sacral pathology requiring partial or total sacrectomy is rare, and reconstructing the ensuing defects requires careful decision-making to minimize morbidity. The purpose of this study was to review the experience of a single institution with reconstructing large sacral defects, to identify risk factors for suboptimal outcomes.

METHODS

A retrospective chart review was conducted of all patients who underwent sacrectomy over a 10-year period. Univariate analysis of differences in risk factors between patients with and without various postoperative complications was performed. Multivariate logistic regression was used to identify predictive variables.

RESULTS

Twenty-eight patients were identified. The most common diagnosis leading to sacrectomy was chordoma (39%). Total sacrectomy was performed on 4 patients, whereas 24 patients underwent partial resection. Reconstructive modalities included 15 gluteal advancement flaps, 4 pedicled rectus abdominis myocutaneous flaps, and 9 paraspinous muscle or other flap types. There was an overall complication rate of 57.1% (n = 12) and a 28.6% (n = 8) incidence of major complications. There were significantly more flap-related complications in patients who underwent total sacrectomy (P = 0.02). Large defect size resulted in significantly more unplanned returns to the operating room (P < 0.01).

CONCLUSION

Consistent with other published series', the overall complication rate exceeded 50%. Defect volume and sacrectomy type were the strongest predictors of postoperative complications and return to the operating room, while reconstructive strategy showed limited power to predict patient outcomes. We recommend that patients anticipated to have large sacral defects should be appropriately counseled regarding the incidence of wound complications, regardless of reconstructive approach.

Risk Factors Associated with Reconstructive Complications Following Sacrectomy

BACKGROUND

Sacral pathology requiring partial or total sacrectomy is rare, and reconstructing the ensuing defects requires careful decision-making to minimize morbidity. The purpose of this study was to review the experience of a single institution with reconstructing large sacral defects, to identify risk factors for suboptimal outcomes.

METHODS

A retrospective chart review was conducted of all patients who underwent sacrectomy over a 10-year period. Univariate analysis of differences in risk factors between patients with and without various postoperative complications was performed. Multivariate logistic regression was used to identify predictive variables.

RESULTS

Twenty-eight patients were identified. The most common diagnosis leading to sacrectomy was chordoma (39%). Total sacrectomy was performed on 4 patients, whereas 24 patients underwent partial resection. Reconstructive modalities included 15 gluteal advancement flaps, 4 pedicled rectus abdominis myocutaneous flaps, and 9 paraspinous muscle or other flap types. There was an overall complication rate of 57.1% (n = 12) and a 28.6% (n = 8) incidence of major complications. There were significantly more flap-related complications in patients who underwent total sacrectomy (P = 0.02). Large defect size resulted in significantly more unplanned returns to the operating room (P < 0.01).

CONCLUSION

Consistent with other published series', the overall complication rate exceeded 50%. Defect volume and sacrectomy type were the strongest predictors of postoperative complications and return to the operating room, while reconstructive strategy showed limited power to predict patient outcomes. We recommend that patients anticipated to have large sacral defects should be appropriately counseled regarding the incidence of wound complications, regardless of reconstructive approach.

Sacral chordoma: clinical experience of a series of 11 patients over 18 years

Sacral chordoma are rare low-to-intermediate grade malignant tumours that occur most commonly within the sacrum. Sacrectomy with wide resection margins seems to offer the best long-term prognosis.  This study aims to review the management of sacral chordomas including the duration of symptoms, features, treatment, complications and local recurrence rate following surgery at a tertiary centre. We retrospectively reviewed 11 patients treated at our institution between years 1999 and 2015. Patient data included age, sex, history, radiographs, surgical details, onset of recurrence, subsequent treatment, disease-free survival and overall survival were analyzed. Nine patients underwent surgical management with 1 through a sacral approach and eight patients through a combined abdominosacral approach. Despite wide resection in our series, sacral chordoma poses a major problem with approximately 60% of patients having local recurrence in their follow-up.

Variables affecting functional improvement in chordoma patients admitted to an inpatient rehabilitation facility: A retrospective review

STUDY DESIGN

Retrospective chart review of patients after surgical resection of chordoma admitted to an inpatient rehabilitation facility.

OBJECTIVE

To evaluate the characteristics associated with improving two or more functional levels and therefore classifying as a substantial responder after an inpatient rehabilitation facility stay in post-resection chordoma patients.

SETTING

Acute inpatient rehabilitation facility in the United States.

METHODS

A total of 40 patients were admitted to an inpatient rehabilitation facility from 2010-2015 after chordoma resection. Demographics, tumor management information, lengths of stay and functional independence measures on admission and discharge were collected. Substantial responders were identified as individuals who improved two or more functional levels based on total FIM score change. Logistic regression was used to analyze the available data for association of quantitative and categorical variables with being a substantial responder.

RESULTS

The categorical variables analyzed in this study (sex, readmission to an acute hospital, Charlson Comorbidity Index, tumor level, nerve sacrifice, recurrent tumor and metatases) were not associated with being a substantial responder. The quantitative variables age and length of stay at the inpatient rehabilitation facility were individually associated with being a substantial responder, while length of stay at the acute hospital was not.

CONCLUSIONS

Patients who were younger were more likely to be classified as substantial responders. Patients with longer lengths of stay at the inpatient rehabilitation facility were also more likely to be classified as substantial responders.

Role of intraoperative radiotherapy in the treatment of sacral chordoma

BACKGROUND CONTEXT

Sacral chordoma is a rare entity with high local recurrence rates when complete resection is not achieved. To date, there are no series available in literature combining surgery and intraoperative radiotherapy (IORT).

PURPOSE

The objective of this study was to report the experience of our center in the management of sacral chordoma combining radical resection with both external radiotherapy and IORT.

STUDY DESIGN

This is a retrospective case series.

PATIENT SAMPLE

The patient sample included 15 patients with sacral chordoma resected in our center from 1998 to 2015.

OUTCOME MEASURES

The outcome measures were overall survival (OS), disease-free survival (DFS), and rates of local and distant recurrences.

METHODS

We retrospectively reviewed the records of all the patients with sacral chordoma resected in our center from 1998 to December 2015. Overall survival, DFS, and rates of local and distant recurrences were calculated. Results between patients treated with or without IORT were compared.

RESULTS

A total of 15 patients were identified: 8 men and 7 women. The median age was 59 years (range 28-77). Intraoperative radiotherapy was applied in nine patients and six were treated with surgical resection without IORT. In 13 patients, we performed the treatment of the primary tumor, and in two patients, we performed the treatment of recurrence disease. A posterior approach was used in four patients. Wide surgical margins (zero residue) were achieved in six patients, marginal margins (microscopic residue) were achieved in seven patients, and there were no patients with intralesional (R2) margins. At a median follow-up of 38 months (range 11-209 months), the 5-year OS in the IORT group was 100% versus 53% in the group of non-IORT (p=.05). The median DFS in the IORT group was 85 months, and that in the non-IORT group was 41 months. In the group without IORT, two patients died and nobody died during the follow-up in the group treated with IORT. High-sacrectomy treated patients had a median survival of 41 months, and low-sacrectomy treated patients had a median survival of 90 months. Disease-free survival in patients without gluteal involvement was 100% at 5 years, and that in patients with gluteal involvement was 40%. All patients with a recurrence in our study had gluteal involvement.

CONCLUSIONS

Multidisciplinary management of sacral chordoma seems to improve local control. The use of IORT, in our experience, is associated with an increase in OS and DFS. The level of resection and gluteal involvement seems to affect survival. The posterior approach is useful in selected cases. Multicenter studies should be performed to confirm the utility of IORT.

Sacral Chordoma: Long-term Outcome of a Large Series of Patients Surgically Treated at Two Reference Centers

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To report on the natural history and long-term outcome of a large series of consecutive primary sacral chordoma patients surgically treated at two reference centers.

SUMMARY OF BACKGROUND DATA

Sacral chordomas are rare tumors with poor long-term prognosis mainly caused by local failure. Till date, a few large series with long follow up are available in literature.

METHODS

All consecutive patients affected by primary localized sacral chordoma operated on at two Italian reference centers between 1981 and 2012 were included. Overall survival (OS), disease free survival (DFS), crude cumulative incidence (CCI) of local recurrence (LR), and distant metastases (DM) were calculated. Multivariable analyses for OS, DFS, LR, and DM were performed.

RESULTS

A total of 99 patients were identified: 65 males and 34 females. Median age was 59 years (range 22-77 yrs), median tumor size was 9 cm (range 4-22). Nineteen patients received pre- or postoperative radiotherapy (RT). Wide (R0) surgical margins were achieved in 46 patients, marginal (R1) margins in 43 patients and intralesional (R2) margins in 10 patients. At a median follow up of 8.7 years (range 1-23.8 yrs) 30 patients died of disease, 31 patients developed local relapse, 16 patients developed distant metastasis, whereas 51 patients are alive without disease. OS and DFS at 5, 10, and 15 year were 92% and 63%, 45% and 62%, 36% and 21%, respectively, without any evidence of a plateau in the curves.CCI of LR and DM were 30% and 9% at 5 years, 46% and 18% at 10 years, 56% and 23% at 15 years. Size of the tumor and quality of surgical margins were the only significant predictors of long-term outcome. DFS for 15 years was, in fact, 49% for R0 and 7% for R1, respectively.

CONCLUSION

In this series, long-term outcome of resected sacral chordoma was poor, with less than 25% patients were disease-free at 15 years. Interestingly, only half of the patients treated with R0 resection had no evidence of recurrence at 15 years. When surgical margins are expected to be positive other treatment modalities should be considered, especially when expected sequelae are substantial as in the case of more cephalad levels of resection.

LEVEL OF EVIDENCE

3.

Chondromyxoid fibroma of the sacrum: A case report and literature review

BACKGROUND

Chondromyxoid fibroma (CMF) is an extremely rare, benign cartilaginous tumor that makes up <0.5% of all bone tumors, typically presenting in the second or third decade of life. CMF of the sacrum is exceedingly rare, with only seven documented cases reported in the neurosurgical literature.

CASE DESCRIPTION

We report a case of a 35-year-old female with a 3 month history of lower back pain after sustaining a fall on her sacrum/coccyx presenting with a progressive complaint of localized lower back pain, occasional urinary retention without incontinence, gluteal hypesthesia, and pressure below the gluteal crease. Imaging demonstrated a large, expansile enhancing soft-tissue lesion involving the sacrum, distal to the S2-3 disc space. The tumor was removed with partial sacrectomy for open en bloc resection with partial nerve sparing. The patient was found at 1.5-year follow-up with the improvement of symptoms, no recurrence, and no residual neurologic dysfunction.

CONCLUSION

Sacral CMF is a rare clinical entity that may mirror more aggressive sacral pathology, including chordoma, in both clinical presentation and imaging characteristics. A review of the available literature regarding diagnosis, surgical management options, and prognosis for sacral CMF is provided.

Chordoma: The Quest for Better Treatment Options

Chordoma is an extremely rare cancer, with an incidence of about one case per million persons per year in the USA and Europe (about 300 and 450 cases per year, respectively). The estimated median overall survival of patients with chordoma is approximately 6–7 years, yielding a rough estimate of chordoma prevalence at about 2000 in the USA and 3000 in Europe. Primary tumor develops along the axial spine between the clivus and sacrum and develops from the residual embryonic notochord. Brachyury (T), a transcription factor required for normal embryonic development, is expressed in the notochord and overexpressed in almost all cases of chordoma. The primary treatment for chordoma is surgical excision with wide local margins, when possible. Radiotherapy also plays a significant role in the adjuvant setting and when surgery is not possible. Unfortunately, in the advanced and/or metastatic setting, where the role of surgery and/or radiation is less clear, treatment options are very limited. To date, there have been no randomized, controlled trials in chordoma that have resulted in defined agents of clinical benefit for systemic treatment. This review briefly describes the natural history and initial treatment of chordoma and focuses on treatment options for advanced disease and potential avenues of research that may lead to improved treatment options in the future.

Low expression of PHLPP1 in sacral chordoma and its association with poor prognosis

Sacral chordoma is a rare spine tumor with a high recurrence rate even after optimal therapy. Previous studies have demonstrated that the PI3K/AKT pathway plays a pivotal role in chordoma, and high expression of pAKT is associated with poor prognosis. Recently, PHLPP was recognized to be a tumor suppressor that targets AKT. We analyzed the expression of PHLPP1 and AKT2 in 37 chordoma samples and 11 fetal nucleus pulposus samples by immunohistochemical staining. Of the chordoma cases, 40.5% (15/37) showed strong cytoplasmic staining (score ≥3) for PHLPP1, which was significantly lower than the 90.9% (10/11) of fetal nucleus pulposus samples (P = 0.004). Conversely, strong immunohistochemical staining for AKT2 was observed in 75.7% (28/37) of chordoma samples, which was significantly higher than 36.4% (4/11) of fetal nucleus pulposus (P = 0.021). Kaplan-Meier survival curves and log-rank test showed that patients with high expression of PHLPP1 experienced longer progression free survival time than those with low PHLPP1 expression (P = 0.011). Further multivariate Cox regression analysis indicated that PHLPP1 expression level and surgical approaches were independent risk factors for chordoma recurrence (P = 0.023 and P = 0.022). However, PHLPP1 expression was not statistically related to patients' total survival time. Conclusively, our results suggest that PHLPP1 plays a crucial role in sacral chordoma, and may be a promising biomarker for prognosis. Meanwhile, manipulation of PHLPP1 expression is also a potential therapeutic approach for the treatment of sacral chordoma.

Case report: Successful treatment of recurrent chordoma and bilateral pulmonary metastases following an 11-year disease-free period

INTRODUCTION

Chordomas are rare but aggressive tumors due to local recurrence and distant metastases. They originate commonly in the sphenooccipital and sacrococcygeal regions, and metastasize to the lungs, bone, skin, liver, and lymph nodes. They occur more frequently in men and people over the age of 40.

PRESENTATION OF CASE

A 28 year-old female presented with sacrococcygeal chordoma for which she received wide local excision and adjuvant radiation therapy. She enjoyed an unusual disease-free survival for 11 years until a routine surveillance scan of the pelvis identified local recurrence. Further work up revealed bilateral pulmonary metastases. She underwent local excision of the recurrent tumor and video-assisted thoracoscopic (VATS) wedge resection of pulmonary metastases. She also received adjuvant radiation therapy to the recurrent resection bed. Two years later, she remains free of disease and symptoms.

DISCUSSION

Chordomas are commonly insensitive to chemotherapy and radiation, making surgery the most successful therapeutic modality. However, there are few guidelines on the surveillance and treatment of recurrent chordoma. We report success with aggressive surgical resection of recurrence and metastasis as well as adjuvant radiation therapy.

CONCLUSION

The prolonged survival of our patient underscores the importance of (1) aggressive surgical resection of chordoma, whether primary, recurrent, or metastatic, with adjuvant radiation therapy, (2) minimization of surgical seeding of tumor, and (3) diligent cancer surveillance.