OBJECTIVES: To describe characteristics of patients with and without positive surgical margins (PSM) and describe the impact of PSM on secondary cancer treatment after radical prostatectomy (RP) with short-term follow-up.
PATIENTS AND METHODS: We analysed data from 2385 consecutive patients who were notified to the Prostate Cancer Registry by 37 Victorian hospitals between August 2008 and February 2012 and were treated by RP. Independent and multivariate models were constructed to predict the likelihood of PSM. Independent and multivariate predictors of secondary treatment following prostatectomy in the initial 12 months post diagnosis were also assessed.
RESULTS: Surgical margin status was collected for 2219/2385 (93%) cases. In total 592/2175 (27.2%) radical prostatectomies resulted in PSM; 102/534 (19.1%) cases in the low risk group, 317/1,218 (26.0%) cases in the intermediate risk group, 153/387 (39.5%) in the high risk group, and 9/11 (81.8%) in the very high risk disease group. PSM were significantly more likely for men having surgery in a hospital where less than ten RPs occur each year (Incidence rate radio[IRR] 1.44 confidence interval [CI] 1.07-1.93) and in the intermediate-, high-, or very-high-risk group, than those for those in the low risk group (Incidence rate radio (IRR) 1.34 [CI] 1.09-1.65, p= 0.007], 1.96 (CI: 1.57-2.45, p< 0.001) 3.81 (CI: 2.60-5.60, p< 0.001) and 2.50 (CI: 1.23-5.11, p=0.012) respectively). Patients with PSM were significantly less likely to have been treated at a private hospital than a public hospital (IRR=0.76, CI: 0.63-0.93, p=0.006) or to have had robot-assisted surgery performed (IRR=0.69, CI: 0.55-0.87, p=0.002) than an open approach. Of the 2182 cases who underwent surgery in the initial 12 months post diagnosis, 1987 (91.1%) received no subsequent treatment, 123 (5.6%) received radiotherapy, 47 (2.1%) received androgen deprivation therapy (ADT) and 23 (1.1%) received a combination of radiotherapy and ADT. Two cases (0.1%) received chemotherapy combined with another treatment. At a multivariate level, predictors of additional treatment following surgery in the initial 12 months included having a PSM compared with clear margins (Odds ratio (OR)=5.61 CI: 3.82-8.22 p< 0.001); pT3 compared with pT2 disease (OR 4.72, CI: 2.69-8.23, p< 0.001); and having high or very-high risk disease compared with low risk disease (OR 4.36, CI: 2.24-8.50, p< 0.001 and 4.50, CI: 1.34-15.17, p=0.015 respectively). Patient age, hospital location and hospital type were not associated with secondary treatment. Patients undergoing robotic-assisted surgery were significantly less likely to receive additional treatment compared with those receiving surgery using the open approach (OR 0.59, CI: 0.39-0.88, p=0.010).
CONCLUSIONS: These data indicate an important association between hospital status and PSMs, with radical prostatectomy cases treated in private hospitals less likely than those in public hospitals to have PSM. Cases treated in lower volume hospitals were more likely to have PSM and less likely to receive additional treatment following surgery in the initial 12 months. Robot-assisted prostatectomy is associated with fewer positive surgical margins compared with the open approach in this non-randomised observational study. Surgical margin status and pathological T3 disease are both important and independent predictor of secondary cancer treatment for patients undergoing radical prostatectomy. A robot-assisted radical prostatectomy approach appears to decrease the risk of men having subsequent treatment, when compared with the open approach.
Written by:
Evans SM, Millar JL, Frydenberg M, Murphy DG, Davis ID, Spelman T, Bolton DM, Giles GG, Dean J, Costello AJ, Frauman AG, Kearns PA, Day L, Daniels C, McNeil JJ. Are you the author?
Department of Epidemiology and Preventive Medicine, Monash University, 3rd Floor, Burnet Building Alfred Hospital, Melbourne, VIC, 3004.
Reference: BJU Int. 2013 Oct 15. Epub ahead of print.
doi: 10.1111/bju.12509
PubMed Abstract
PMID: 24128010
UroToday.com Prostate Cancer Section
