Type II collagen as specific marker for mesenchymal chondrosarcomas compared to other small cell sarcomas of the skeleton

Abstract

Mesenchymal chondrosarcoma is a rare, usually highly malignant chondrogenic neoplasm. The diagnosis of mesenchymal chondrosarcoma can be challenging, it nonetheless has important therapeutic and diagnostic implications. Thus, biopsies of mesenchymal chondrosarcomas without conspicuous cartilaginous differentiation cannot be safely distinguished from other small cell mesenchymal neoplasms such as Ewing's sarcoma and peripheral neuroendrocrine tumors, synovial sarcomas and hemangiopericytomas, because all of these neoplasms might show overlapping histological features, and so far, there have been no safe immunohistochemical markers available in order to differentiate these neoplasms. In our study on a large series of mesenchymal chondrosarcomas (n ¼ 30) and other small cell sarcomas (Ewing's sarcomas (n ¼ 12), synovial sarcomas (n ¼ 6), hemangiopericytomas (n ¼ 5), small cell osteosarcomas (n ¼ 3), and desmoplastic small round cell tumors (n ¼ 1)), we could establish the presence of type II collagen in the extracellular tumor matrix of the small cell areas of mesenchymal chondrosarcomas as a specific and sensitive marker to identify mesenchymal chondrosarcomas and to exclude other small cell neoplasms (except chondroblastic areas in small cell osteosarcomas). In contrast, the S-100 protein was less sensitive and vimentin and total collagen content unspecific for discriminating these neoplasms. Thus, the presence of type II collagen in the extracellular tumor matrix significantly facilitates the diagnosis of mesenchymal chondrosarcomas in the absence of histologically visible chondroid matrix formation.

The combination of CD99 and NKX2.2, a transcriptional target of EWSR1-FLI1, is highly specific for the diagnosis of Ewing sarcoma

“…However, it may be difficult to distinguish ES from mesenchymal chondrosarcoma or small cell carcinoma, especially in small biopsy specimens. In such a situation, additional immunohistochemical markers including type II collagen, Sox9, FLI-1 [21][22][23], and TTF-1 and the detection of fusion genes specific for mesenchymal chondrosarcoma such as HEY1-NCOA2 [24] may be helpful.…”

Primary orbital mesenchymal chondrosarcoma: a case report and literature review

“…These researchers coined the term mesenchymal chondrosarcoma (MC), which has subsequently come to define a subtype of chondrosarcoma. The incidence of MC varies from 1 to 8% of all chondrosarcomas diagnosed [2,3]. It is an aggressive neoplasm with a high tendency for late recurrence and occasional delayed distant metastasis [2].…”

Chondrosarcoma of Bone

“…8 and 9). For this reason, wide excision is sometimes the recommended treatment for low-grade chondrosarcoma [33,34]. Wide excision often produces functional deficits and is a more morbid procedure than intralesional treatment [50].…”