• 1
    Polascik TJ, Oesterling JE, Partin AW. Prostate specific antigen: a decade of discovery—what we have learned and where we are going. J Urol 1999;162: 293306.
  • 2
    Lilja H, Christensson A, Dahlen U, Matikainen MT, Nilsson O, Pettersson K, Lövgren T. Prostate-specific antigen in serum occurs predominantly in complex with alpha1-antichymotrypsin. Clin Chem 1991;37: 161825.
  • 3
    Stenman UH, Leinonen J, Alfthan H, Rannikko S, Tuhkanen K, Alfthan O. A complex between prostate-specific antigen and alpha1-antichymotrypsin is the major form of prostate-specific antigen in serum of patients with prostatic cancer: assay of the complex improves clinical sensitivity for cancer. Cancer Res 1991;51: 2226.
  • 4
    Catalona WJ, Smith DS, Wolfert RL, Wang TJ, Rittenhouse HG, Ratliff TL, Nadler RB. Evaluation of percentage of free serum prostate-specific antigen to improve specificity of prostate cancer screening. JAMA 1995;274: 121420.
  • 5
    Catalona WJ, Partin AW, Slawin KM, Brawer MK, Flanigan RC, Patel A, Richie JP, deKernion JB, Walsh PC, Scardino PT, Lange PH, Subong EN, et al. Use of the percentage of free prostate-specific antigen to enhance differentiation of prostate cancer from benign prostatic disease: a prospective multicenter clinical trial. JAMA 1998;279: 15427.
  • 6
    Catalona WJ, Partin AW, Finlay JA, Chan DW, Rittenhouse HG, Wolfert RL, Woodrum DL. Use of percentage of free prostate-specific antigen to identify men at high risk of prostate cancer when PSA levels are 2.51 to 4 ng/ml and digital rectal examination is not suspicious for prostate cancer: an alternative model. Urology 1999;54: 2204.
  • 7
    Catalona WJ, Roehl KA, Antenor JAV. Robustness of free PSA measurements to reduce unnecessary biopsies in the 2.6 to 4.0 ng/ml total PSA range. J Urol 2001;165(Suppl): 2823.
  • 8
    Jung K, Stephan C, Elgeti U, Lein M, Brux B, Kristiansen G, Rudolph B, Hauptmann S, Schnorr D, Loening SA. Molecular forms of prostate-specific antigen in serum with concentrations of total prostate-specific antigen <4 μg/l—are they useful tools for early detection and screening of prostate cancer? Int J Cancer 2001;93: 75965.
  • 9
    Carlson GD, Calvanese CB, Partin AW. An algorithm combining age, total prostate-specific antigen (PSA) and percent free PSA to predict prostate cancer: results on 4298 cases. Urology 1998;52: 45561.
  • 10
    Virtanen A, Gomari M, Kranse R, Stenman UH. Estimation of prostate cancer probability by logistic regression: free and total prostate-specific antigen, digital rectal examination and heredity are significant variables. Clin Chem 1999;45: 98794.
  • 11
    Finne P, Finne R, Auvinen A, Juusela H, Aro J, Maattanen L, Hakama M, Rannikko S, Tammela TL, Stenman U. Predicting the outcome of prostate biopsy in screen-positive men by a multilayer perceptron network. Urology 2000;56: 41822.
  • 12
    Babaian RJ, Fritsche H, Ayala A, Bhadkamkar V, Johnston DA, Naccarato W, Zhang Z. Performance of a neural network in detecting prostate cancer in the prostate-specific antigen reflex range of 2.5 to 4.0 ng/ml. Urology 2000;56: 10006.
  • 13
    Sargent DJ. Comparison of artificial neural networks with other statistical approaches. Cancer 2001;91: 163642.
  • 14
    Partin AW, Murphy GP, Brawer MK. Report on prostate cancer tumor marker workshop 1999. Cancer 2000;88: 95563.
  • 15
    Meyer A, Jung K, Lein M, Rudolph B, Schnorr D, Loening SA. Factors influencing the ratio of free to total prostate-specific antigen in serum. Int J Cancer 1997;74: 6306.
  • 16
    Semjonow A, Brandt B, Oberpenning F, Roth S, Hertle L. Discordance of assay methods creates pitfalls for the interpretation of prostate-specific antigen values. Prostate Suppl 1996;7: 316.
  • 17
    Jung K, Stephan C, Lein M, Brux B, Sinha P, Schnorr D, Loening SA. Receiver-operating characteristic as a tool for evaluating the diagnostic performance of prostate-specific antigen and its molecular forms—what has to be considered? Prostate 2001;46: 30710.
  • 18
    Kairisto V, Poola A. Software for illustrative presentation of basic clinical characteristics of laboratory tests—GraphROC for Windows. Scand J Clin Lab Invest 1995;55(Suppl 222): 4360.
  • 19
    Stephan C, Jung K, Lein M, Sinha P, Schnorr D, Loening SA. Molecular forms of prostate-specific antigen and human kallikrein 2 as promising tools for early diagnosis of prostate cancer. Cancer Epidemiol Biomarkers Prev 2000;9: 113347.
  • 20
    Partin AW, Catalona WJ, Southwick PC, Subong EN, Gasior GH, Chan DW. Analysis of percent free prostate-specific antigen (PSA) for prostate cancer detection: influence of total PSA, prostate volume and age. Urology 1996;48: 5561.
  • 21
    Wymenga LF, Duisterwinkel FJ, Groenier K, Visser-van Brummen P, Marrink J, Mensink HJ. Clinical implications of free-to-total immunoreactive prostate-specific antigen ratios. Scand J Urol Nephrol 2000;34: 1817.
  • 22
    Catalona WJ, Smith DS, Ornstein DK. Prostate cancer detection in men with serum PSA concentrations of 2.6 to 4.0 ng/ml and benign prostate examination. Enhancement of specificity with free PSA measurements. JAMA 1997;277: 14525.
  • 23
    Djavan B, Zlotta A, Kratzik C, Remzi M, Seitz C, Schulman CC, Marberger M. PSA, PSA density, PSA density of transition zone, free/total PSA ratio and PSA velocity for early detection of prostate cancer in men with serum PSA 2.5 to 4.0 ng/ml. Urology 1999;54: 51722.
  • 24
    Carlson GD, Calvanese CB, Childs SJ. The appropriate lower limit for the percent free prostate-specific antigen reflex range. Urology 1998;52: 4504.
  • 25
    Hammerer P, Graefen M, Henke RP, Haese A, Huland E, Huland H. Ratio free/total PSA (%f-PSA) in men with total PSA 0.5–3 ng/ml–improvement for prostate cancer detection? J Urol 2000;163(Suppl): 277A.
  • 26
    Lein M, Stephan C, Jung K, Schnorr D, Loening S. Relation of free PSA/total PSA in serum for differentiating between patients with prostatic cancer and benign hyperplasia of the prostate: which cut-off should be used? Cancer Invest 1998;16: 459.
  • 27
    Stephan C, Lein M, Jung K, Schnorr D, Loening SA. Can prostate specific antigen derivatives reduce the frequency of unnecessary prostate biopsies [letter]? J Urol 1997;157: 1371.
  • 28
    Li W, Ren Y, Mee V, Wong PY. Prostate-specific antigen ratio correlates with aggressiveness of histology grades of prostate cancer. Clin Biochem 1999;32: 317.
  • 29
    Tornblom M, Norming U, Adolfsson J, Becker C, Abrahamsson PA, Lilja H, Gustafsson O. Diagnostic value of percent free prostate-specific antigen: retrospective analysis of a population-based screening study with emphasis on men with PSA levels less than 3.0 ng/ml. Urology 1999;53: 94550.
  • 30
    Snow PB, Smith DS, Catalona WJ. Artificial neural networks in the diagnosis and prognosis of prostate cancer: a pilot study. J Urol 1994;152: 19236.
  • 31
    Wei JT, Zhang Z, Barnhill SD, Madyastha KR, Zhang H, Oesterling JE. Understanding artificial neural networks and exploring their potential applications for the practicing urologist. Urology 1998;52: 16172.
  • 32
    Fox MP, Reilly AA, Schneider E. Effect of the ratio of free to total prostate-specific antigen on interassay variability in proficiency test samples. Clin Chem 1999;45: 11819.
  • 33
    Horninger W, Bartsch G, Snow PB, Brandt JM, Partin AW. The problem of cut-off levels in a screened population. Cancer 2001;91: 166772.
  • 34
    Lee CT, Scardino PT. Percent free prostate-specific antigen for first-time prostate biopsy. Urology 2001;57: 5948.
  • 35
    Mettlin C, Chesley AE, Murphy GP, Bartsch G, Toi A, Bahnson R, Church P. Association of free PSA percent, total PSA, age and gland volume in the detection of prostate cancer. Prostate 1999;39: 1538.
  • 36
    Tornblom M, Norming U, Becker C, Lilja H, Gustafsson O. 2001. Variation in percentage-free prostate-specific antigen (PSA) with prostate volume, age and total PSA level. BJU Int 2001;87: 63842.
  • 37
    Stephan C, Lein M, Jung K, Schnorr D, Loening SA. The influence of prostate volume on the ratio of free to total prostate specific antigen in serum of patients with prostate carcinoma and benign prostate hyperplasia. Cancer 1997;79: 1049.
  • 38
    Arcangeli CG, Humphrey PA, Smith DS, Harmon TJ, Shepherd DL, Keetch DW, Catalona WJ. Percentage of free serum prostate-specific antigen as a predictor of pathologic features of prostate cancer in a screening population. Urology 1998;51: 55864.
  • 39
    Pannek J, Rittenhouse HG, Chan DW, Epstein JI, Walsh PC, Partin AW. The use of percent free prostate specific antigen for staging clinically localized prostate cancer. J Urol 1998;159: 123842.
  • 40
    Bangma CH, Kranse R, Blijenberg BG, Schröder FH. The free-to-total serum prostate specific antigen ratio for staging prostate carcinoma. J Urol 1997;157: 5447.
  • 41
    Graefen M, Karakiewicz PI, Scardino PT, Kattan MW, Haese A, Hammerer PG, Palisaar J, Huland E, Huland H. Percentage of free PSA (%fPSA) is not an indepentent predictor of pathological stage or PSA recurrence in patients with localized prostate cancer treated with radical prostatectomy (RP). J Urol 2001;165(Suppl): 281.
  • 42
    Henricks WH, England BG, Giacherio DA, Oesterling JE, Wojno KJ. Serum percent-free PSA does not predict extraprostatic spread of prostate cancer. Am J Clin Pathol 1998;109: 5339.
  • 43
    Southwick PC, Catalona WJ, Partin AW, Slawin KM, Brawer MK, Flanigan RC, Patel A, Richie JP, Walsh PC, Scardino PT, Lange PH, Gasior GH, et al. Prediction of post-radical prostatectomy pathological outcome for stage T1c prostate cancer with free prostate specific antigen: a prospective multicenter clinical trial. J Urol 1999;162: 134651.
  • 44
    Marks LS, Llanes AS, Linton HJ, Gasior CL, Millar LS, Mikolajczyk SD, Rittenhouse HG, Munroe WA, Sokoll LJ, Partin AW, Chan DW. BPSA is a potential serum marker for benign prostatic hyperplasia (BPH). J Urol 2001;165(Suppl): 266.
  • 45
    Mikolajczyk SD, Grauer LS, Millar LS, Hill TM, Kumar A, Rittenhouse HG, Wolfert RL, Saedi MS. A precursor form of PSA (pPSA) is a component of the free PSA in prostate cancer serum. Urology 1997;50: 7104.
  • 46
    Mikolajczyk SD, Millar LS, Marker KM, Rittenhouse HG, Wolfert RL, Marks LS, Charlesworth MC, Tindall DJ. Identification of a novel complex between human kallikrein 2 and protease inhibitor-6 in prostate cancer tissue. Cancer Res 1999;59: 392730.
  • 47
    Nam RK, Diamandis EP, Toi A, Trachtenberg J, Magklara A, Scorilas A, Papnastasiou PA, Jewett MA, Narod SA. Serum human glandular kallikrein-2 protease levels predict the presence of prostate cancer among men with elevated prostate-specific antigen. J Clin Oncol 2000;18: 103642.
  • 48
    Partin AW, Catalona WJ, Finlay JA, Darte C, Tindall DJ, Young CY, Klee GG, Chan DW, Rittenhouse HG, Wolfert RL, Woodrum DL. Use of human glandular kallikrein 2 for the detection of prostate cancer: preliminary analysis. Urology 1999;54: 83945.