T. Ishida et Hd. Dorfman, MASSIVE CHONDROID DIFFERENTIATION IN FIBROUS DYSPLASIA OF BONE (FIBROCARTILAGINOUS DYSPLASIA), The American journal of surgical pathology, 17(9), 1993, pp. 924-930
Eight cases of fibrocartilaginous dysplasia (fibrous dysplasia with ma
ssive cartilaginous differentiation) of bone are reported. The age of
the patients ranged from 4 to 26 years, with an average of 17.5 years.
The male/female ratio was 1:1. In two patients the lesions occurred i
n a setting of polyostotic fibrous dysplasia. The anatomic sites most
frequently affected were the femur and tibia. The proximal femur was t
he most common site. Roentgenograms showed well-demarcated lucent lesi
ons of ground-glass opacity. In addition, stippled or ring-like calcif
ications suggesting cartilaginous elements were seen in six cases. His
tologically, hyaline cartilage islands were found in juxtaposition to
a fibro-osseous lesion characteristic of fibrous dysplasia. Enchondral
ossification was commonly seen, frequently showing columnar arrangeme
nt of cartilage cells mimicking a growth plate. The cartilage may show
moderate atypism. The important thing is to recognize the benign natu
re of chondroid elements in fibrous dysplasia. Even if cartilage domin
ates the histologic picture, it is important to identify the fibro-oss
eous elements and thereby avoid the misdiagnosis of chondrosarcoma.