Benign osteoblastoma: quantitative histological distinction from osteoid osteoma

The author performed on 10 cases of benign osteoblastoma and osteoid osteoma a comparative quantitative histological analysis using an optical line-mesh grid for sampling. Tissue components under the line crossing were counted five hundred times in every case making a total of five thousand counts for each group. It was demonstrated that 1. in osteoblastoma the amount of stroma is roughly by 10 per cent elevated and the amount of osteoid about 10 per cent less in comparison with osteoid osteoma. 2. As far as the osteoblast lining, capillaries and giant cells are concerned, there is no basic numerical difference between the two lesions. Experiences gained by qualitative histological comparison are also described. His results are favouring the concept of benign osteoblastoma as an entity with true tumour nature.