OBJECTIVES: To test (-2)proPSA (p2PSA), p2PSA/fPSA (%p2PSA) and Prostate Health Index (PHI) accuracy in predicting prostate cancer (PCa) in obese men and to test whether PHI is more accurate than PSA in predicting PCa in obese patients.
PATIENTS AND METHODS: The analysis consisted of a nested case-control study from the PRO-psa Multicentric European Study (PROMEtheuS) project. The study is registered at http://www.controlled-trials.com/ISRCTN04707454. The primary outcome was to test sensitivity, specificity and accuracy (clinical validity) of serum p2PSA, %p2PSA and PHI, in determining PCa at prostate biopsy in obese men (BMI ≥ 30 kg/m2 ), compared to tPSA, fPSA and %fPSA. The number of avoidable prostate biopsies (clinical utility) was also assessed. Multivariable logistic regression models were complemented by predictive accuracy analysis and decision curve analysis.
RESULTS: Over 965 subjects, 383 (39.7%) were normal-weight (BMI < 25 kg/m2 ), 440 (45.6%) were overweight (BMI 25-29.9 kg/m2 ) and 142 (14.7%) were obese (BMI ≥ 30 kg/m2 ). Among obese patients, PCa was found in 65 subjects (45.8%), with a higher percentage of GS ≥7 diseases (67.7%). PSA, p2PSA, %p2PSA and PHI were significantly higher, and %fPSA significantly lower in patients with PCa (p< 0.001). In multivariable logistic regression models, PHI significantly increased accuracy of the base multivariable model by 8.8% (p=0.007). At PHI cut-off of 35.7, 46 (32.4%) biopsies could have been avoided.
CONCLUSION: In obese patients, PHI is significantly more accurate than current tests in predicting PCa.
Abrate A, Lazzeri M, Lughezzani G, Buffi N, Bini V, Haese A, de la Taille A, McNicholas T, Palou Redorta J, Gadda GM, Lista G, Kinzikeeva E, Fossati N, Larcher A, Dell'Oglio P, Mistretta F, Freschi M, Guazzoni G. Are you the author?
Division of Oncology, Unit of Urology, URI, IRCCS Ospedale San Raffaele, Università Vita-Salute San Raffaele, Milan, Italy.
Reference: BJU Int. 2014 Aug 18. Epub ahead of print.