[Use of frozen sections to assess surgical margins during radical prostatectomy]. / Impiego dell'esame estemporaneo al congelatore per la valutazione dei margini chirurgici in corso di prostatectomia radicale

ABSTRACT

INTRODUCTION: At present there is no consensus on the use of frozen sections (FS) during radical prostatectomy. Several groups have proposed the benefit of FS although the studies differ widely in sampling methods and sites where FS were taken. This study aims to evaluate the usefulness and reliability of standard assessment of FS in multiple sites during radical prostatectomy. METHODS: During open radical prostatectomy in all patients we sampled tissue from the urethral stump, the neurovascular bundles, the Denonvillier fascia and the bladder neck after removing the prostate. Where FS showed positive margins, further periprostatic tissue was resected from the prostatic bed until negative margins were achieved. The results of FS were compared with margin status of final pathology. RESULTS: From 1998 to 2004 we performed FS during 250 consecutive open radical prostatectomies (104 nerve sparing procedures). 66 patients had positive FS (26.4%) and 53 patients had positive surgical margins at final pathology (21.2%). All patients with positive FS had negative margins when further tissue was resected in the prostatic bed. During nerve sparing procedures positive FS were found in 14 patients. In these cases the procedure was converted into standard prostatectomy by resecting the neurovascular bundles. Sensibility and specificity were both 90%. Positive and negative predictive values were respectively 72% and 97%. CONCLUSIONS: Standard assessment of FS in multiple sites during radical prostatectomy achieved sensibility and specificity as high as 90%. Although the resection of urethral stump and tissue close to the neurovascular bundles could compromise functional results, standard assessment of FS in multiple sites could help the surgeon to reduce the positive surgical margins, to monitor the oncological safety of a nerve sparing procedure and to improve the pathological staging.