Chordoma

Steven H. Lin and Michelle Alonso-Basanta

 Background

What are chordomas?

Chordomas are rare, slow-growing, locally aggressive neoplasms of bone arising from embryonic remnants of the notochord.

Where do chordomas most commonly arise?

Chordomas most commonly arise in 3 locations in the axial skeleton:

1. 
   

   Spheno-occipital region of the skull base (35%)

   
   
2. 
   

   Sacrococcygeal region (50%)

   
   
3. 
   

   Vertebral column (15%)

In craniocervical chordomas, the most common sites are the dorsum sellae, clivus, and nasopharynx.

What are the most common histologic subtypes seen for chordomas?

Most common histologic subtypes of chordoma:

1. 
   

   Conventional: most common, no cartilaginous or mesenchymal components

   
   
2. 
   

   Chondroid: 5%–15%, contains cartilaginous components but is distinct from chondrosarcoma

   
   
3. 
   

   Dedifferentiated or sarcomatous transformation: 2%–8%, aneuploid tumors interspersed in areas of conventional chordomas, poorer survival

What features characterize conventional chordomas?

Gelatinous, pink or gray masses with solid or cystic areas. Microscopically, characteristic physaliphorous cells are present.

What histologic types of chordomas are most commonly found in the skull base?

Conventional is still the most common, though the chondroid type has a predilection for the cranial region (one third of cranial chordomas are chondroid).

What tumor antigens are commonly found on chordomas?

Epithelial membrane antigen (EMA) and cytokeratin are commonly found on chordomas.

What % of chordoma pts have metastatic Dz, and what distant sites are most commonly involved?

~25% of chordoma pts have metastatic Dz, with lungs, liver, and bones being most commonly involved.

 Workup/Staging

How do pts with chordomas present clinically?

Depends on the site of origin, but pts with base of skull chordomas present with intermittent diplopia, HA, neck pain, or other lower CN findings. Invasion of the cavernous sinus produces diplopia and facial numbness.

What is important in the workup for skull base tumors?

Skull base tumor imaging workup: MRI/CT (to assess local bone destruction) and Bx

What are the T1-T2 MRI features of chordomas?

T1-T2 MRI features of chordomas:

1. 
   

   T1: intermediate to low signal intensity, with marked but heterogeneous enhancement with gadolinium

   
   
2. 
   

   T2: very high signal intensity

Besides chordomas, what must be on the DDx of tumors arising in the axial skeleton?

Related posts:

Brainstem Glioma Oral Cavity Cancer Locally Advanced Breast Cancer Metastatic Prostate Cancer Testicular Nonseminomatous Germ Cell Tumor Mycosis Fungoides

Stay updated, free articles. Join our Telegram channel

Join