The quest for the perfect prostate biopsy continues.

UNTIL well into the 1980s, biopsy of the prostate often relied on a few cores using a device such as the Vim-Silverman needle digitally guided transperineally or transrectally into a palpably abnormal prostate. In this pre-prostate specific antigen (PSA) era prostate cancers were often detected at an advanced clinical stage. The modern era of prostate biopsy was ushered in during the late 1980s with the development of the spring loaded biopsy needle and the transrectal ultrasound (TRUS) probe. Since that time the state of the art has evolved from the TRUS directed biopsy of suspicious lesions to the sextant and now extended 10 to 12-core biopsy schema using local anesthesia. The decision to perform prostate biopsy today is often based on the interpretation of changes in serum PSA leading to cancer detection in palpably normal prostate glands. The current gold standard prostate biopsy is based on standard gray scale TRUS imaging. Although early investigations suggested that prostate cancer is seen as a hypoechoic lesion on TRUS, the reality today is that most PSA detected cancers have a highly variable appearance and do not demonstrate unique characteristics on gray scale imaging. While a sonographically distinct lesion is biopsied when seen, distinguishing benign from malignant tissue with standard ultrasound is challenging. Standard gray scale TRUS is effective in providing an accurate size determination as well as in guiding the biopsy needle and ensuring adequate sampling of the various regions of the gland. However, it usually falls short in the detection of all prostate cancers that may be present due to the common small and multifocal nature of the disease. Changes in the management of prostate cancer require a much more careful assessment of the prostate cancer than ever. No longer is it appropriate to identify simply the largest or index tumor and make a simple diagnosis of prostate cancer. Standard and evolving approaches such as active surveillance and focal therapy ideally require that all lesions in the prostate be detected and characterized to determine the appropriate course of action. Multifocality is the rule rather than the exception, and identification of the tumor with an aggressive phenotype can no lon-