CCR7 and Ewing sarcoma: Although CCR7 does not appear to be a significant factor in osteosarcoma or Ewing sarcoma progression, >80% of human chondrosarcoma (cartilage-initiated cancer) tissue samples had elevated CCR7 levels in conjunction with the EMT marker, transcription factor, Slug, resulting in a higher tumor grade and lower 5 year survival of patients [245].