前立腺癌における針吸引生検の評価

Abstract

前立腺癌35例を対象として検討した.針吸引生検はその検体採取及びその診断にいまだ問題を有し, 現時点において必ずしも針生検にかわりうるものではない

We studied 35 needle aspiration biopsies of the prostatic cancer to evaluate the reliability for screening, as compared with the transrectal or transperineal needle biopsy of the same patients. Eight specimens were unsatisfactory for cytological study, only 77.4% of the 35 aspirations being cytologically evaluable. False negative aspiration biopsies occupied 22.7%. Histopathological evaluation was possible for all of the needle biopsies and the false negative rate was 5.7%. To examine how accurately aspiration biopsy or needle biopsy reflects the true histologic grade of prostatic cancer, both the cytologic grade of the aspirations and histologic grade of the biopsies were compared with the grade of the prostatectomy specimens. The aspiration biopsy was undergraded in 2 (11.8%) overgraded in 2 (11.8%) and correctly graded in 14 (82.4%) out of 17 cases. The needle biopsy was undergraded in 1 (3.2%), overgraded in 2 (6.5%) and correctly graded in 28 (90.3%) out of 31 cases. There was no significant difference in grading accuracy rate between cytology of the aspiration and histology of the needle biopsy. We conclude that the cytological grade is as reliable as needle biopsy, but aspiration biopsy is not a more efficient screening test for prostatic neoplasms than needle biopsy, considering the higher percentage of speciments unsatisfactory for aspiration and false negative in this small series.