Primary maxillofacial chordoma: a rare case report and literature review

Primary maxillofacial chordoma is extremely rare. We herein report a very rare case of a recurrent maxillofacial chordate tumor that was diagnosed in a 56-year-old woman who underwent three tumor resections. After surgical treatment, the patient healed well with an Eastern Cooperative Oncology Group score of 1. She was discharged to a local hospital for adjuvant radiotherapy. Close follow-up was ongoing at the time of this writing. Radical surgery and adjuvant radiotherapy remain the main treatment strategies for chordoma. Postoperative radiotherapy is particularly important. Our experience is to administer a total dose of 50 Gy to a clearly delineated target. If appropriate comprehensive treatment is available, distant metastasis of primary chordoma is rare, and neck dissection is therefore not generally recommended. Neck lymph node dissection is generally not recommended.

Mutation Analysis of Nine Chordoma Specimens by Targeted Next-Generation Cancer Panel Sequencing

Background: Chordoma is a rare primary malignant bone tumour. Treatment options are mainly restricted to surgical excision, since chordomas are largely resistant to conventional ionising radiation and chemotherapy. Thus, there is a strong need to gain more thorough insights into the molecular biology and genetics of chordoma to allow for the development of new therapeutic options. We performed an ultra-deep sequencing analysis to find novel mutations in cancer associated genes in chordomas to date unseen with Sanger sequencing.

Material and Methods: Nine chordomas (skull base (n=3), mobile spine (n=4), and sacrum/coccyx (n=2) were screened for mutations in 48 cancer genes using the Hot Spot Cancer Panel (Illumina). All putative mutations were compared against multiple databases (e.g. NCBI, COSMIC, PolyPhen, EGB, SIFT) and published Copy Number Variation (CNV) data for chordoma.

Results: Our results showed mutations with a frequency above 5% in tumorsuppressor- and onco-genes, revealing new possible driver genes for chordomas. We detected three different variants accounting for 11 point mutations in three cancer associated genes (KIT, KDR and TP53). None of the detected mutations was found in all samples investigated. However, all genes affected interact or are connected in pathway analysis. There were no correlations to already reported CNVs in the samples analysed.

Conclusions: We identified mutations in the associated genes KIT, KDR, and TP53. These mutations have been described previously and have been predicted to be tolerated. Further results on a larger series are warranted. The driver mechanisms of chordoma still have to be identified.

Extended ultrastructural characterization of chordoma cells: the link to new therapeutic options

Chordomas are rare bone tumors, developed from the notochord and largely resistant to chemotherapy. A special feature of this tumor is the heterogeneity of its cells. By combining high pressure freezing (HPF) with electron tomography we were able to illustrate the connections within the cells, the cell-cell interface, and the mitochondria-associated endoplasmic reticulum membrane complex that appears to play a special role among the characteristics of chordoma. These lipid raft-like regions are responsible for lipid syntheses and for calcium signaling. Compared to other tumor cells, chordoma cells show a close connection of rough endoplasmic reticulum and mitochondria, which may influence the sphingolipid metabolism and calcium release. We quantified levels of ceramide and glycosylceramide species by the methyl tert-butyl ether extraction method and we assessed the intracellular calcium concentration with the ratiometric fluorescent dye Fura-2^AM. Measurements of the changes in the intracellular calcium concentration revealed an increase in calcium due to the application of acetylcholine. With regard to lipid synthesis, glucosylceramide levels in the chordoma cell line were significantly higher than those in normal healthy cells. The accumulation of glycosylceramide in drug resistant cancer cells has been confirmed in many types of cancer and may also account for drug resistance in chordoma. This study aimed to provide a deep morphological description of chordoma cells, it demonstrated that HPF analysis is useful in elucidating detailed structural information. Furthermore we demonstrate how an accumulation of glycosylceramide in chordoma provides links to drug resistance and opens up the field for new research options.

Skull base chordoma presenting as nasopharyngeal mass with lymph node metastasis

Spheno-occipital chordomas can rarely present as nasopharyngeal mass. Metastases occur only in advanced disease. They can pose a diagnostic dilemma when information about diagnosis of the primary tumor is not available. We present cytological findings in upper cervical lymph node of a case of nasopharyngeal chordoma and discuss possible differential in such a location.

Differential expression of microRNA (miRNA) in chordoma reveals a role for miRNA-1 in Met expression

Emerging evidence suggests that microRNA (miRNA) expression signatures in cancer may have important diagnostic, prognostic, and therapeutic value, but there is no data on miRNA expression in chordoma. The purpose of this study was to identify the role of miRNAs in human chordoma. We analyzed miRNA expression in chordoma-derived cell lines and chordoma tissue by using miRNA microarray technology with unsupervised hierarchical clustering analysis. The relative expression levels of these miRNAs were confirmed by real-time quantitative RT-PCR and Northern blot analysis. To characterize the potential role of miRNA-1, miRNA-1 was stably transfected into a chordoma cell line, UCH1. The expression of miRNA-1 targeted gene Met in chordoma tissues was also studied. We observe that human chordoma tissues and cell lines can be distinguished from normal muscle tissue by comparing miRNA expression profiles. Several miRNAs were differentially expressed in chordoma cell lines compared to controls, and similar expression patterns were found in primary chordoma tissues. Importantly, we were able to show for the first time, to our knowledge, that expression of miRNA-1 and miRNA-206, two miRNAs implicated in a number of other cancer types, were markedly decreased in both chordoma tissues and cell lines. When chordoma cell lines were transfected with miRNA-1, downregulation of known miRNA-1 targets was observed. These targets included Met and HDAC4-two genes that were observed to be overexpressed in chordoma. Our results demonstrate that some miRNAs are differentially expressed in chordoma and, in particular, miRNA-1 may have a functional effect on chordoma tumor pathogenesis.

Challenges of local recurrence and cure in low grade malignant tumors of the spine

STUDY DESIGN

Systematic review and ambispective multicenter cohort study.

OBJECTIVE

1. To compare the effects of wide/marginal (en bloc) resection with intralesional resection on local recurrence and survival for chordomas and chondrosarcomas of the spine. 2. To determine the influence of radiation therapy in the management of chordomas and chondrosarcomas.

SUMMARY OF BACKGROUND DATA

Chordomas and chondrosarcomas of the spine are prone to local recurrence and death despite being low-grade malignant tumors. No study to date has enough numbers or adequate scientific rigor to determine the influence of resection or radiation therapy on outcome.

METHODS

A systematic review was performed to evaluate the 2 objectives. In addition an ambispective multicenter cohort analysis of chordomas and chondrosarcomas was performed. The GRADE system of analysis integrating the results of the systematic review, the multicenter cohort study and the expert opinion of the Spine Oncology Study Group (SOSG) was used to arrive at treatment recommendations.

RESULTS

A total of 63 articles were included in the systematic reviews. Evidence was low quality. En bloc resection appeared to improve both local recurrence and disease free survival in Chordoma and Chondrosarcoma. Radiation therapy had a positive impact on the management of Chordoma and Chondrosarcoma with predictably low side effects. The cohort analysis showed significantly decreased local recurrence for Chordoma (P < 0.0001) and Chondrosarcoma (P < 0.0001) with en bloc resection, and significantly decreased death for both Chordoma (P = 0.0001) and Chondrosarcoma (P = 0.0015) with en bloc resection.

CONCLUSION

When wide or marginal margins (en bloc) are achieved in surgical resection of chordomas and chondrosarcomas of the spine there is a decrease in local recurrence and mortality. Therefore, en bloc resection should be undertaken for the treatment of chordomas and chondrosarcomas of the spine. Strong Recommendation, Moderate Quality Evidence.Radiation therapy of at least 60 to 65 Gy equivalents is indicated as an adjuvant treatment for chordoma and chondrosarcoma of the spine when there has been incomplete resection or an intralesional margin. Weak Recommendation, Low Quality Evidence.