DISTINCTION BETWEEN FOCALLY ACCELERATED BONE-FORMATION AND OSTEOMALACIA IN CARCINOMA OF PROSTATE METASTISIZED TO BONE

We studied the histological indices of skeletal turnover in 40 patients with carcinoma of the prostate and skeletal metastases in order to determine the prevalence of osteomalacia. In 20 patients biopsied through uninvolved bone, the histological indices of bone turnover were normal. In particular, osteoid seam width and bone formation rates were consistently normal, indicating the absence of osteomalacia. In biopsies from tumour-laden bone, hyperosteoidosis was present, usually associated with increased amounts of woven collagen and consistently associated with high rates of bone formation and mineralisation. It was concluded that hyperosteoidosis in prostatic cancer is rarely due to osteomalacia.