Postoperative prostate‐specific antigen nadir improves accuracy for predicting biochemical recurrence after radical prostatectomy: Results from the Shared Equal Access Regional Cancer Hospital (SEARCH) and Duke Prostate Center databases

Abstract

Objectives We previously showed that prostate-specific antigen (PSA) nadir after radical prostatectomy (RP) significantly predicts biochemical recurrence (BCR). Herein, we sought to explore the effect of including PSA nadir into commonly used models on their accuracy to predict BCR after RP. Methods This was a retrospective analysis of 943 and 1792 subjects from the Shared Equal Access Regional Cancer Hospital (SEARCH) and Duke Prostate Cancer (DPC) databases, respectively. The discrimination accuracy for BCR of seven previously published models was assessed using concordance index and compared with and without adding PSA nadir level in SEARCH. Using data from SEARCH, we developed a new nomogram incorporating PSA nadir to other known predictors (preoperative PSA, pathological Gleason score, PSA nadir level, surgical findings, prostate weight, body mass index and race) of BCR and externally validated it in the DPC. Results In SEARCH, the mean concordance index across all seven nomograms was 0.687. After the inclusion of PSA nadir, the concordance index increased by nearly 7% (mean = 0.753). The concordance index of the new nomogram in SEARCH was 0.779 (bias-corrected = 0.767), which was 5% better than the next best model. In DPC, the new nomogram yielded a concordance index of 0.778. Conclusion The addition of postoperative PSA nadir to commonly used nomograms increased their accuracies by nearly 7%. Based upon this, we developed and externally validated a new nomogram, which was well calibrated and highly accurate, and is a potentially valuable tool for patients and physicians to predict BCR after RP.

Fifth-Generation Digital Immunoassay for Prostate-Specific Antigen by Single Molecule Array Technology

“…While PSA was undetectable in approximately half the patients, recurrence risk could nonetheless be stratified depending on nadir PSA level (19). This result mirrored other studies (20-24), indicating a significant relevance of ultra low PSA measurement for predicting long term BCR-free survival.…”

Adjuvant and Salvage Radiotherapy After Prostatectomy: American Society of Clinical Oncology Clinical Practice Guideline Endorsement

“…Fortunately, this risk can be calculated using nomograms that incorporate not only preoperative and pathologic findings but also postoperative PSA values. 9 Specifically, some men who are candidates for adjuvant radiotherapy based on entry criteria in reported clinical trials and an undetectable PSA may have favorable outcomes (ie, those with focal positive margins or low prostatectomy Gleason score), and for these men, the absolute benefits of adjuvant radiotherapy (compared with early salvage radiotherapy) may be low. Alternatively, men with more favorable pathology but a detectable postoperative PSA can be at high risk of clinically meaningful recurrence and thus stand to experience great benefits with adjuvant radiotherapy.…”

Adverse pathology and undetectable ultrasensitive prostate‐specific antigen after radical prostatectomy: is adjuvant radiation warranted?

“…Beyond adverse pathological features portending an increased risk of BCR , postoperative PSA nadir is an important risk stratification tool after RP . A prior study from the Shared Equal Access Regional Cancer Hospital (SEARCH) database showed that adding postoperative PSA nadir to established post‐RP nomograms increased their ability to predict BCR by 7% . Additionally, not only do men with undetectable ultrasensitive PSA (<0.01 ng/mL) have considerably lower BCR rates compared with men with elevated postoperative PSA levels , but there is also evidence to suggest ultrasensitive assays provide better BCR risk stratification vs less sensitive PSA assays (i.e.…”

“…Additionally, not only do men with undetectable ultrasensitive PSA (<0.01 ng/mL) have considerably lower BCR rates compared with men with elevated postoperative PSA levels , but there is also evidence to suggest ultrasensitive assays provide better BCR risk stratification vs less sensitive PSA assays (i.e. detection limit <0.1 ng/mL) . While men with an undetectable (<0.01 ng/mL) postoperative PSA level have lower overall BCR rates , outcomes of men with adverse pathology and undetectable ultrasensitive PSA levels after RP are unknown.…”