Impact of prior biopsy scheme on pathologic features of cancers detected on repeat biopsies.

The object of our study was to characterize the biopsy features of cancers detected in a repeat biopsy population stratified on the basis of the type of prior negative biopsy. We studied 218 patients with a prior negative biopsy who underwent a 10-core extended systematic biopsy scheme, and a subset (n = 139) underwent additional 6 anteriorly directed biopsies. Clinicopathologic features of patients with cancer on the biopsy were compared as a function of type of prior negative biopsy. Overall and unique cancer detection rates were calculated for each of the biopsy sites. Cancer detection rates tended to be higher in patients who had undergone a prior sextant biopsy compared to a prior extended biopsy scheme (39% vs. 28%). Trends towards more positive cores and greater total core length of cancer involvement were seen in patients who had undergone a prior negative sextant biopsy. Apical and laterally directed biopsies had higher overall and unique cancer detection rates in patients who had undergone a prior negative sextant biopsy. Anteriorly directed biopsies had a low unique cancer detection rate in all patients. We conclude that in patients undergoing repeat biopsy, the detection rate is affected by the extent of the prior biopsy. Clinicopathologic features of cancers detected on repeat biopsy tend to be worse in patients who have undergone a prior negative sextant biopsy compared to a negative prior extended biopsy.