[Dynamic study of the hormonal levels and tumor markers after the first administration of long-acting LH-RH analogue in patients with prostate cancer].

The dynamics of hormonal levels and tumor markers after the first administration of long-acting luteinizing hormone-releasing hormone (LH-RH) analogue were evaluated in patients with prostate cancer. Eight patients with histopathologically proved prostate cancer who were previously untreated were studied. The surge in plasma testosterone was recognized in 7 patients after the first administration of a long-acting LH-RH analogue, and reached the highest level after the 3rd day in 6 patients and 14th day in 1 patient. The onset of flare-up reaction due to a transient increase in plasma testosterone was recognized in 3 patients, whose clinical symptoms and signs were increased bone pain in 2 patients and acute urinary retention in 1 patient. An abnormal level of serum prostatic acid phosphatase (PAP) and prostate specific antigen (PSA) was observed in 7 of the 8 patients before treatment. The serum PAP and PSA levels slightly increased after treatment in 4 and 3 patients, respectively. These findings suggest that the combination of estrogen or antiandrogen would allow a safer use of long-acting LH-RH analogue to prevent the risk of a flare-up reaction associated with the first administration of long-acting LH-RH analogue.