Serum lactate dehydrogenase in combination with free-to-total serum prostate specific antigen ratio for diagnosis of prostate cancer.

Abstract

Evaluate the utility of serum lactate dehydrogenase (LDH) in combination with free-to-total serum prostate specific antigen ratio (%fPSA), for diagnosis of prostate cancer (PC) with serum total prostate specific antigen (PSA) levels in the intermediate range of 4 to 10 ng/mL. The following variables were analysed: PSA, %fPSA, and LDH. Two categories of patients were included in the analysis: NOT PC and PC. We studied 134 patients, 112 had NOT PC and 22 had PC. We defined the following multivariable score (S): S = A + B, where A and B are coefficients of LDH and %fPSA, respectively. AUC values were 0.719 (p = 0.0036), 0.749 (p = 0.0082), and 0.816 (p = 0.0001) for %fPSA, LDH, and S, respectively. Using the proposed S increases by 18% specificity compared to only using the %fPSA parameter. LDH in combination with %fPSA improves diagnostic performance for detection of PC compared to using only %fPSA.