Lesions missed on prostate biopsies in cases sent in for consultation

BACKGROUND. There are no reports on how often lesions are missed on prostate needle biopsies. METHODS. Over a 10-month period, 8/99 to 5/00, 3,251 prostate biopsy cases were seen in consultation. RESULTS. We identified 87 (2.7%) patients with missed lesions (n = 9 academic hospitals; n = 44 community hospitals; n = 34 commercial labs). Overall, 119 lesions were missed in 87 patients. Missed lesions were as follows: small atypical glands suspicious for cancer (41 lesions in 35 patients), prostatic adenocarcinoma (39 cancers in 32 patients), high grade prostatic intraepithelial neoplasia (HGPIN) (34 lesions in 30 patients), and HGPIN with adjacent small atypical glands (five lesions in five patients) - some men with more than one type of missed lesion. Detection of the missed lesions would have resulted in either: a definite change in care in 15 of 3,251 (0.5%) patients or a possible change in care (bilateral cancer vs. unilateral cancer; HGPIN vs. atypical) in 17 (0.5%) patients. In 21 (24%) of the cases, the slides were seen by at least two pathologists prior to consultation at our hospital. CONCLUSIONS. Although the number of prostate biopsies with missed lesions in a consultbased population of prostate biopsies appears relatively high (2.7%), the detection of the missed lesions would have only effected a definite change in care in 0.5% of all patients or a possible change in care in another 0.5% of patients. Our data underestimates missed lesions, as the entire specimen was not submitted for review in 41% of cases. Although our incidence of missed lesions gives some indication as to the magnitude of the problem, it cannot be equated with the risk of missing lesions in unselected cases.