Prostate Specific Antigen Regression and Progression after Androgen Deprivation for Localized and Metastatic Prostate Cancer

Abstract

To identify prostate specific antigen (PSA) functions of prognostic significance in regard to treatment with androgen deprivation for prostate cancer we analyzed the pretreatment PSA, PSA half-life, PSA nadirs, times to PSA elevation and PSA doubling times in 245 patients with localized and 78 with metastatic disease who were treated with this modality. There was a direct correlation between the pretreatment PSA and the time to PSA elevation in patients with localized cancer (p = 0.000003) but no significant correlation in those with metastatic cancer. The PSA half-life was highly variable and did not correlate with other PSA functions of prognostic significance. Incremental increases in the PSA nadir correlated with the time to PSA elevation in patients with localized and metastatic cancer (p < 0.000001 and p = 0.00009, respectively), and with other parameters of prognostic significance. The median PSA doubling time in 26 patients with localized cancer in whom distant metastases did not develop (7.5 months) was significantly longer than that in 7 in whom new metastases developed (2.5 months) and in 43 with preexisting metastatic cancer (2.5 months) (p < 0.05 and p < 0.0001, respectively). In the 7 patients with localized cancer in whom metastases developed the median of the ratios of the PSA when the metastases were manifest and the pretreatment PSA was 0.14, and in 24 patients with preexisting metastatic cancer the median of the ratios of the antemortem PSA and the pretreatment PSA was 1.2. These data show that PSA synthesis by prostate cancer is reduced after androgen deprivation but that the PSA nadir and PSA doubling time following treatment provide important prognostic information.

Hormone naïve prostate cancer: predicting and maximizing response intervals

“…in 1995, PSA nadir was a very significant predictor of response to hormone therapy. 49 In this study, after patient exclusions, 245 patients with localized and 78 patients with newly diagnosed metastatic prostate cancer were treated with ADT in the form of orchiectomy or LH-RH agonist. PSA regression, nadir and doubling times were calculated for the patient cohorts.…”

“…Patients whose nadir was < 1 enjoyed a much greater disease-free interval compared to patients who experienced a PSA nadir > 4. 49 …”

Kombinierte Brachytherapie und antiandrogene Therapie beim Prostatakarzinom

“…Der PSA-Nadir ist nach einer Multivarianzanalyse als wichtigster determinierender Faktor für das krankheitsfreie Überleben anzusehen. In der Studie von Critz hatte ein PSA-Nadir von > 1 ng/ml in allen Patienten zu einem Rezidiv geführt [6,15]. Fuks [19]…”

Prostate-specific antigen

“…Following androgen deprivation, most patients experience a dramatic decline and then stabilisation of PSA levels, lasting for various amounts of time. According to Fowler et al, the median half-life of PSA decline after initiation of hormonal therapy was 8.7 days for patients with metastatic disease and 10.5 days for patients with localised disease, with the majority of patients reaching a nadir of < 1 ng/ml [65]. As previously discussed with surgery and radiation, patients who fail hormonal therapy have altered PSA kinetics.…”

“…As previously discussed with surgery and radiation, patients who fail hormonal therapy have altered PSA kinetics. In Fowler's study, men with localised disease had a postfailure PSA doubling time of 7.5 months compared to patients with metastatic disease who had PSA doubling times of 2.5 months after becoming androgen-independent [65].…”