Light micrograph of a section through a low-grade (Grade 1) chondrosarcoma. The nuclei of chondrocytes (tumour cells) are arranged in clusters in a background of bluish cartilaginous matrix. The nuclei lack significant cytologic atypia. Chondrosarcoma is a malignant tumour which shows chondroid (cartilaginous) differentiation. It is a tumour of adulthood and old age, most commonly presenting in 4th to 6th decades of life. The most common locations are the pelvic bones, ribs, shoulder girdle and the femur (thigh bone). Haematoxylin and eosin stain.