Pathomorphology of malignant chondrogenic bone tumors--an analysis of 94 cases from the Hamburg Bone Tumor Register (1974-1989)

Abstract

89 central and 5 periosteal chondrosarcomas identified between 1974-1989 were reviewed in a retrospective study. The purpose of this study was to examine the morphological characteristics of different types of chondrosarcomas and to describe remarkable features of location, age distribution and male to female ratio. We distinguish four types of centrally located chondrosarcoma: classical chondrosarcomas, dedifferentiated chondrosarcomas, mesenchymal chondrosarcomas and clear cell chondrosarcomas. Five periosteal chondrosarcomas were represented. Classical chondrosarcomas as well as clear cell chondrosarcomas indicate a significant predominance of males; no sex predilection in dedifferentiated and mesenchymal chondrosarcomas was seen. Nearly 60% of classical and mesenchymal chondrosarcomas occur in the trunk. 85% of dedifferentiated chondrosarcomas are located in the long bones of the limbs. The most common location of clear cell chondrosarcoma is the proximal part of the femur. There is a marked predilection for mesenchymal chondrosarcomas in the second and third decades of life. The mean age of patients with classical chondrosarcomas was 54 years, but clear cell chondrosarcomas occur 10 years earlier and dedifferentiated chondrosarcomas 10 years later. Characteristically, classical chondrosarcomas produce a pure chondroid matrix with variable differentiation of tumour chondrocytes. The most important histological feature of the dedifferentiated chondrosarcoma is the close association of two different cellular components. One of these consists of cartilage, which is generally well differentiated. In most of our cases the second component showed features of osteosarcoma (50%). Mesenchymal chondrosarcoma is characterized by concentric infiltration of cartilage islands by small tumour cells.(ABSTRACT TRUNCATED AT 250 WORDS)