[-2]proPSA versus ultrasensitive PSA fluctuations over time in the first year from radical prostatectomy, in an high-risk prostate cancer population: A first report

BACKGROUND - [-2]proPSA and its derivatives have an higher diagnostic accuracy than PSA in predicting prostate cancer (PCa). In alternative to PSA, ultrasensitive PSA (uPSA) and [-2]proPSA could be potentially useful in recurrent disease detection.

This research focused on [-2]proPSA and uPSA fluctuations over time and their possible clinical and pathological determinants, in the first year after RP.

METHODS - A cohort of 106 consecutive patients, undergoing RP for high-risk prostate cancer (pT3/pT4 and/or positive margins), was enrolled. No patient received either preoperative/postoperative androgen deprivation therapy or immediate adjuvant RT, this latter for patient choice. [-2]proPSA and uPSA were measured at 1, 3, 6, 9, 12 months after RP; their trends over time were estimated by the mixed-effects linear model. The uPSA relapse was defined either as 3 rising uPSA values after nadir or 2 consecutive uPSA >0.2 ng/ml after RP.

RESULTS - The biochemical recurrence (BCR) rate at 1 year after RP was either 38.6 % (in case of 3 rising uPSA values) or 34.9 % (in case of PSA >0.2 ng/ml after nadir), respectively. The main risk factors for uPSA fluctuations over time were PSA at diagnosis >8 ng/ml (p = 0.014), pT (p = 0.038) and pN staging (p = 0.001). In turn, PSA at diagnosis >8 ng/ml (p = 0.012) and pN (p < 0.001) were the main determinants for [-2]proPSA trend over time. In a 39 patients subgroup, uPSA decreased from month 1 to 3, while [-2]proPSA increased in 90 % of them; subsequently, both uPSA and [-2]proPSA increased in almost all cases. The [-2]proPSA trend over time was independent from BCR status either in the whole cohort as well in the 39 men subgroup.

CONCLUSIONS - Both uPSA and [-2]proPSA had independent significant fluctuations over time. PSA at diagnosis >8 ng/ml and pathological staging significantly modified both these trends over time. Since BCR was not confirmed as determinant of [-2]proPSA fluctuations, its use as marker of early biochemical relapse may not be actually recommended, in an high-risk prostate cancer patients population.

BMC urology. 2016 Mar 24*** epublish ***

S De Luca, R Passera, A Sottile, C Fiori, R M Scarpa, F Porpiglia

Division of Urology, San Luigi Gonzaga Hospital and University of Torino, Orbassano, Italy., Division of Nuclear Medicine, San Giovanni Battista Hospital and University of Torino, Corso AM Dogliotti 14, 10126, Torino, Italy. Division of Laboratory Medicine, Candiolo Cancer Institute, Candiolo, Italy., Division of Urology, San Luigi Gonzaga Hospital and University of Torino, Orbassano, Italy., Division of Urology, San Luigi Gonzaga Hospital and University of Torino, Orbassano, Italy., Division of Urology, San Luigi Gonzaga Hospital and University of Torino, Orbassano, Italy.