[Kinetic study of local relapse in prostatic cancer]

The change of both prostatic volume and bone metastasis was observed from the period of castration to death in 23 cases of prostatic cancer. As for the change of prostatic volume, they were classified into two groups. One group was called "local progressive type". In this group, prostatic volume reduced exponentially after the treatment of castration, then increased exponentially after a transient period. Another group was called "metastatic progressive type". In this group, prostatic volume did not change after the treatment of castration although the degree of bone metastasis advanced severely. The regression speed after castration (tau) was faster in local progressive type than in metastatic progressive type. This tau had a close relationship to the prognosis of each case. In local progressive type, doubling time (DT) during relapsed period was calculated in 13 cases. An inverse correlation was found between tau and DT. This correlation might be able to lead the conclusion that the ratio between residual androgen sensitive cancerous tissue and residual androgen insensitive cancerous tissue related to the local progression in relapsed prostatic cancer.