Effects of dichloromethylene diphosphonate on the osteolytic and osteoplastic effects of rat prostate adenocarcinoma cells.

A model system of prostate adenocarcinoma (PA) in Lobund-Wistar rats is described in which the transplanted tumor cells (PA-III) were inoculated sc over the calvaria. A local tumor developed that, when attached to the bone, caused erosion and fragmentation of the bone, with adjacent osteoplastic changes and metastases to the lungs. The attachment of the tumor to the bone was enhanced if the periosteum was scratched during the inoculation of tumor cells. The destructive effect on bone structure was also induced by in vivo transplanted PA-I and PA-IV cells, but not by PA-II cells. In rats that were pretreated with dichloromethylene diphosphonate, the local PA-III tumors developed with metastases to the lungs, but the calvariae were intact.