Outcome of radical prostatectomy in primary circulating prostate cell negative prostate cancer

Abstract

IntroductionAround 90% of prostate cancers detected using the serum prostate specific antigen (PSA) as a screening test are considered to be localised. However, 20–30% of men treated by radical prostatectomy experience biochemical failure within two years of treatment. The presence of primary circulating prostate cells (CPCs) in the blood of these men implies a dissemination of the tumour and could indicate a greater risk of treatment failure.ObjectiveTo evaluate the use of the number of primary CPCs detected before surgery in the prediction of biochemical failure at ten years.HypothesisThe dissemination of cancer cells to distant sites will determine the patient’s prognosis. The absence of primary CPCs in men undergoing radical prostatectomy for prostate cancer may imply a less aggressive disease and therefore could be utilised as a prognostic factor to predict biochemical failure after surgery.Methods and patientsA single-centre observational study of a cohort of 285 men who underwent radical prostatectomy as monotherapy for prostate cancer, in whom the number of CPCs prior to treatment was determined, and who were followed up for ten years to determine biochemical failure. A Cox proportional risks with polynomial fractions analysis was used to predict biochemical failure based on the number of primary CPCs detected. A decision curve analysis was performed for the model obtained.ResultsKaplan–Meier curves for biochemical free survival at ten years was 47.34% (95% CI 38.71–55.48%). It is important to note that in CPC negative men, the ten years Kaplan–Meier biochemical-free survival was 90.35% (95% CI 75.0–96.27) whereas in men who were primary CPC positive, the biochemical free survival rate was 30.00% (95% CI 20.34–40.60%).The Coxs´model to predict biochemical failure using transformed data with a power of minus one for the number of primary CPCs detected, showed a Harrell´s C concordance index of 0.74 and a decision analysis curve showing a net benefit of CPC detection over other risk factors to predict biochemical failure.ConclusionsThe number of primary CPCs detected before surgery permits a good prediction of subsequent biochemical failure in men undergoing radical prostatectomy as monotherapy for prostate cancer. Men negative for primary CPCs have a biochemical-free survival of over 90% at ten years and should be considered for curative surgery.

The presence of primary circulating prostate cells is associated with upgrading and upstaging in patients eligible for active surveillance

“…Thus as a pre-treatment biomarker the presence of CPCs suggests that AO may not be the most adequate treatment option. It is important to note that primary CPCs have a limited prognostic value, independent of the method used to detect them [20, 21], but that men CPC negative have an excellent ten year biochemical failure free survival of > 90% [22] when treated with radical prostatectomy.…”

The significance and clinical utility of the detection of primary malignant circulating prostate cells: a review of the evidence

“…[99] Using a positive/negative cutoff value, men negative for circulating tumor cells have a significantly better 10-year biochemical free failure survival after radical prostatectomy than men positive for CPCs. [100] When used as a predictive prognostic factor and compared with predictive nomograms, using the CellSearch ® system [101] or the PSA/P504S combined immunocytochemical assay, [102] there was little if any improvement in predicting the prognosis of men pretreatment [ Table 2].…”