Editorial Comment

Abstract

This report demonstrates that the extent of margin positivity measured morphometrically correlates with an increased risk of biochemical recurrence. It is somewhat surprising that this finding only applied only to men with Stage pT2+ disease (ie, positive margin because of intraprostatic incision) and not those with extraprostatic extension. Throughout the report by Cao et al, their cohort with a positive margin because of intraprostatic incision is referred to as “Stage pT2” disease. This is inaccurate, because these patients had tumor at a margin where it is unknown if the tumor were organ confined or had extraprostatic extension, because the edge of the prostate at the positive margin site has been left in the patient and could not be assessed pathologically. More appropriately, these cases should be referred to as pT2+ or pT2x, meaning that everywhere else in the radical prostatectomy specimen the tumor was organ confined but the stage at the area of the positive margin is unknown. In a study performed at our institution of 108 cases of Gleason score 7 with nonfocal extraprostatic extension (pT3a) and positive surgical margins, we found a strong association between the length of the positive margin and the Gleason score of the tumor at the margin and the development of biochemical recurrence. 1 Brimo F. Partin A.W. Epstein J.I. Tumor grade at the margins of resection in radical prostatectomy specimens is an independent predictor of prognosis. Urology. 2010; 76: 1206-1209 Abstract Full Text Full Text PDF PubMed Scopus (71) Google Scholar We were able to stratify the grade at the margins into 3 categories: 3 + 3, 3 + 4, and 4 + 3 or greater (4 + 3 and 4 + 4 at the positive margin carried equal prognostic information). Possible explanations for why our study found a positive margin length significant for pT3a disease in contrast to the report by Cao et al reflects differences in the methods of processing the radical prostatectomy specimens, patient population, and follow-up length. Not all the specimens in the report by Cao et al were submitted in entirety in contrast to those in our study. The study by Cao et al had 71.8% of cases with Gleason score 7. In contrast, we restricted our analysis to only those men with Gleason score 7. We wished to assess the grade at the margin, which would not have been a factor for Gleason score 6 or 8 cancer. 1 Brimo F. Partin A.W. Epstein J.I. Tumor grade at the margins of resection in radical prostatectomy specimens is an independent predictor of prognosis. Urology. 2010; 76: 1206-1209 Abstract Full Text Full Text PDF PubMed Scopus (71) Google Scholar Cao et al included a few cases with seminal vesicle invasion and lymph node metastases, as well as those with pT2+. In contrast, in our study, we only considered those with pT3a disease, and we excluded cases with intraprostatic incision. 1 Brimo F. Partin A.W. Epstein J.I. Tumor grade at the margins of resection in radical prostatectomy specimens is an independent predictor of prognosis. Urology. 2010; 76: 1206-1209 Abstract Full Text Full Text PDF PubMed Scopus (71) Google Scholar We did not assess Stage pT2+ disease in our most recent analysis, because a previous study of ours had already found that the length of margin positivity was predictive for Stage pT2+ disease. 2 Chang A.Y. Nielsen M.E. Hernandez D.J. et al. The significance of positive surgical margin in areas of capsular incision in otherwise organ confined disease at radical prostatectomy. J Urol. 2007; 178: 1306-1310 Abstract Full Text Full Text PDF Scopus (85) Google Scholar The mean follow-up period was 32.7 months in the study by Cao et al compared with a median of 72 months in our study. 1 Brimo F. Partin A.W. Epstein J.I. Tumor grade at the margins of resection in radical prostatectomy specimens is an independent predictor of prognosis. Urology. 2010; 76: 1206-1209 Abstract Full Text Full Text PDF PubMed Scopus (71) Google Scholar We agree with the conclusions of Cao et al that the extent of positive margins should be quantified morphometrically in radical prostatectomy reports. However, we would extend their findings to recommend this conclusion for all radical prostatectomy specimens, not only for those with Stage pT2+ disease. Ability of Linear Length of Positive Margin in Radical Prostatectomy Specimens to Predict Biochemical RecurrenceUrologyVol. 77Issue 6PreviewTo determine whether the linear length of a positive margin (LLPM) in radical prostatectomy specimens is associated with the risk of biochemical recurrence (BCR). Full-Text PDF ReplyUrologyVol. 77Issue 6PreviewWe greatly appreciate the comments from Dr. Epstein and colleagues on our work.1 Full-Text PDF