THE RADIOGRAPHIC STAGE OF GIANT-CELL TUMOR-RELATED TO STROMAL CELLS PROLIFERATION - TISSUE-CULTURES IN 13 CASES

The clinical behavior of giant cell tumor is related to the radiologic al appearance, To test the hypothesis that in vitro proliferation of t he neoplastic stromal cell population of giant cell tumors is related to the radiological appearance, this study was undertaken, A prospecti ve analysis of the cells migrating from 13 consecutive tumors was cond ucted. Growth curves and population doubling-times (PDT) for first and fifth passages were calculated and alkaline phosphatase levels were m easured and compared to preoperative radiographic staging. A strong ne gative correlation was found between PDT and the radiographic stage. T umors in stages I and II (low aggressiveness) were found to have an av erage cell population doubling-time of 11 (SD 2.2) days, while those i n stage III (high aggressiveness) showed a doubling-time of 6 (SD 2.2) days, Low alkaline phosphatase activity was noted in all cultures, a finding consistent with the putative preosteoblastic potential of thes e stromal cells, This putative origin is also indicated by the differe ntiation response to retinoic acid, The findings suggest that the in v itro proliferation of the mononuclear stromal cell population of giant cell tumors is related to the radiographic stage and may predict the clinical behavior of these tumors.