RELATIONSHIP BETWEEN DIURNAL RHYTHM OF SERUM TESTOSTERONE AND 2 PROSTATIC MARKERS (PSA AND PAP) IN UNTREATED PROSTATE-CANCER

Objective. To clarify the relation between diurnal rhythm of serum lev els of testosterone and two prostatic markers, prostate-specific antig en (PSA) and prostatic acid phosphatase (PAP). Methods. Blood was obta ined every four hours during a thirty-two-hour period from fourteen me n with untreated prostate cancer. Results. Serum levels of PSA and PAP showed circadian rhythm in 4 and 5 patients, respectively About half of the remaining patients, the highest or nearly highest peaks of seru m levels of PSA or PAP were observed in the afternoon rather than the morning. In 3 patients, circadian rhythms were not observed in serum l evels of PAP, but the fluctuation patterns were the same as those of t estosterone and showed synchronous movement. In 7 patients, serum test osterone levels were followed by the same fluctuation pattern for eith er PSA or PAP after some time delay. Little change in serum levels of PSA was seen throughout the thirty-two-hour period despite large fluct uations of testosterone and PAP levels in 5 patients. Conclusions. Clo se relation between the fluctuation in serum levels of PSA and PAP, an d that in serum levels of testosterone during diurnal periods could be considered. However, the relationship between serum testosterone leve ls and those of PSA and PAP was ambiguous because of both the differen ce in the time delay of PSA and PAP in relation to testosterone and th e small fluctuation in PSA despite obvious fluctuations in testosteron e and PAP in some cases.