Partial Sampling of Radical Prostatectomy Specimens Detection of Positive Margins and Extraprostatic Extension
Departments of *Urology †Pathology, Miller School of Medicine, University of Miami, Miami, FL.The American journal of surgical pathology (Impact Factor: 5.15). 10/2012; 37(2). DOI: 10.1097/PAS.0b013e318268ccc1
Currently there is no global agreement as to how extensively a radical prostatectomy specimen should be sectioned and histologically examined. We analyzed the ability of different methods of partial sampling in detecting positive margin (PM) and extraprostatic extension (EPE)-2 pathologic features of prostate cancer that are most easily missed by partial sampling of the prostate. Radical prostatectomy specimens from 617 patients treated with open radical prostatectomy between 1992 and 2011 were analyzed. Examination of the entirely submitted prostate detected only PM in 370 (60%), only EPE in 100 (16%), and both in 147 (24%) specimens. We determined whether these pathologic features would have been diagnosed had the examination of the specimen been limited only to alternate sections (method 1), alternate sections representing the posterior aspect of the gland in addition to one of the mid-anterior aspects (method 2), and every section representing the posterior aspect of the gland in addition to one of the mid-anterior aspects, supplemented by the remaining ipsilateral anterior sections if a sizeable tumor is seen (method 3). Methods 1 and 2 missed 13% and 21% of PMs and 28% and 47% of EPEs, respectively. Method 3 demonstrated better results missing only 5% of PMs and 7% of EPEs. Partial sampling techniques missed slightly more PMs and EPEs in patients with low-risk to intermediate-risk prostate cancer, although even in high-risk cases none of the methods detected all of the studied aggressive pathologic features.
- [Show abstract] [Hide abstract]
ABSTRACT: Background: RP for localized PCa was introduced at Rigshospitalet in 1995. Since then, the incidence of PCa and number of RPs performed every year has increased enormously. Presently, RP is performed a six different hospitals in Denmark. No previous studies have meticulously described outcomes of RP in Denmark. This PhD-thesis focuses on surgical and oncological outcome after RP at Rigshospitalet. The primary purpose was to describe biochemical outcome, risk factors associated with positive surgical margins, and the impact of margin location on risk of biochemical recurrence. Material and methods: The PhD-thesis is based on results from approximately 1,300 men who underwent RP between 1995 and 2011 at Rigshospitalet. The patients have been followed prospectively in a local database. BR was defined as the first PSA ≥ 0.2 ng/ml and time to BR was calculated from the date of surgery. Analysis of time to BR was done using Kaplan-Meier estimation and Cox regression analysis including both pre- and postoperative parameters. The association between preoperative and surgical parameters, including surgeon and nerve-sparing surgery, and PSM was analysed using logistic regression analysis. Results: The 10-year estimated BRFS was 75%, 60% and 39% for low-, intermediate-, and high-risk patients, respectively. An in-depth analysis of high-risk patients demonstrated a 10-year metastasis-free and cancer-specific survival of 85% and 90%, respectively. A PSM was demonstrated to increase the risk of BR up to 3 fold. The location of PSM was found to be associated with the risk of BR, i.e. non-apical PSM had the highest risk of BR compared to margin negative and apical PSM, especially in pT2 tumours. A number of factors were found to correlate with the risk of PSM, especially preoperative PSA, surgeon and nerve-sparing surgery. Conclusions: This thesis demonstrates that outcome of RP at Rigshospitalet is comparable to international results. Our studies confirm the prognostic importance of PSM, also in pT2 disease, and indicate that location of PSM in pT2 may influence future selection of patients for adjuvant treatment. Further, the selection of candidates for nerve-sparing surgery seems to be associated with an increased risk of PSM and subsequent BR. Therefore, the selection for nerve-sparing surgery remains unclear.
- [Show abstract] [Hide abstract]
ABSTRACT: In addition to clinical data, prostatic biopsy (Bx) reports orient urologists in outlining the patient's treatment options. Discontinuous involvement of a core by multiple foci of cancer is not infrequent; however, there is currently no consensus as to which method of quantification should be the standard. We applied 2 distinct approaches to quantify the length of cancer foci in the Bx and compared the results to prostatectomy (RP) parameters. All patients with matched Bx and RP treated by the same medical team between 2006 and 2010 were consecutively included in the study. Tumor extent in the Bx was estimated by multiple approaches, and the length was measured in millimeters. The subset of cases with discontinuous foci of cancer in a single core was initially reported by adding each foci and ignoring the benign intervening prostatic tissue, which was designated as additive quantification (AQ). Upon slide review, these foci were reassessed as a single focus and measured by linear quantification (LQ). RPs were partially embedded according to the International Society of Urological Pathology recommendations, and the percentage of tumor was evaluated with graphic precision. Mean percentage of the tumor in RP (%RP) and in the Bx were arbitrarily classified as limited (<6%) and nonlimited (≥6%). Bx parameters were then correlated with %RP and margin status. All methods of quantification of the tumor in the Bx obtained excellent correlation with %RP. LQ and AQ diverged in 14/38 patients, with a mean total length of cancer of 5.8 mm more than the length obtained by LQ in the same population, accurately upgrading 6/14 cases to nonlimited. This subset (LQ>AQ) was more often seen in Bx with significantly more positive cores (P=0.003) of predominantly Gleason score 7 and associated with positive surgical margins in RP (P=0.034) independent of %RP (21% vs. 19% in the margin-negative cases). However, in the subset of Bx in which the tumor infiltration was continuous (AQ=AL) positive margins were indeed associated with tumor extent (31% vs. 6% in margin-negative cases). Discontinuous foci of cancer in a single core were most often seen in Bx sampling nonlimited disease, and this event was associated with positive surgical margins. LQ of cancer improved the performance of the Bx in predicting RP tumor extent relative to the traditional millimetric sum. Our findings support the idea that discontinuous foci may represent undersampling of a larger irregular nodule; however, this study is based on routine reports and does not directly access tumor biology.
- [Show abstract] [Hide abstract]
ABSTRACT: This study reports a modified point-count method for quantifying the extent of carcinoma in prostatectomy specimens (n = 143), as adapted from Billis et al., Int Braz J Urol. 2003.29:113-120. The prostates were studied as follows: The basal/apical margins were sampled using the cone method. The remainder of the gland was divided into 12 quadrant-shaped regions that were sampled using two slices. Eight equidistant points were marked directly on the coverslip over each fragment. The points inside the tumoral areas were counted and expressed as both the percentage of prostate gland involvement by carcinoma (PGI) and the tumor volume (TV). A significant correlation between the preoperative PSA levels and each of the three quantitative estimations were observed, with improved correlations with the PGI and TV values obtained using the point-count method (viz. number of slices involved (NSI) (r = 0.32), PGI (r = 0.39) and TV (r = 0.44). With the data sets stratified into three categories, all three methods correlated with multiple parameters, including Gleason scores ≥7, primary Gleason scores ≥4, perineural/angiolymphatic invasion, extraprostatic extension, seminal vesicle invasion and positive margins. All three quantitative methods were associated with morphologic features of tumor progression. The results obtained using this modified point-count method correlate more strongly with preoperative PSA levels.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.