Classics of urology: a half century history of the most frequently cited articles (1955-2009).

To identify and characterize the most frequently cited articles published in Journals dedicated to Urology over the last 50 years. A Pubmed search was performed of all articles published in the 13 most cited urological journals between 1955 and 2009. Articles with more than 100 citations were identified as "classic", and were analyzed further. Of 97,554 articles published during this time, 1239 articles were cited more than 100 times. The most common topic among classic articles was prostate cancer and prostate-specific antigen (33.5%), followed by bladder cancer and benign prostatic hyperplasia. A further analysis was performed for the 50 most frequently cited articles ("top-50").