Head-to-head comparison of two online nomograms for prostate biopsy outcome prediction
Mário Oliveira1, Vera Marques, António Pedro Carvalho
1Department of Urology, Hospital de Braga, Braga, Portugal. mariooliveira@ecsaude.uminho.pt
Study Type:
Diagnosis (exploratory cohort).
Level Of Evidence:
2b. What's known on the subject? and What does the study add? In recent years, several nomograms were developed in an effort to decrease the number of unnecessary prostate biopsies. The European SWOP-PRI and the North American PCPT are among the most popular. However, evidence on the relative predictive accuracy is lacking. A head-to-head comparison on the diagnostic accuracy of two previously validated prostate cancer risk predictors on biopsy confirmed the superiority of these tools over PSA alone. Moreover, in the studied population, the European SWOP-PRI proved to be more accurate than the North American PCPT-CRC.
Objective:
To compare the diagnostic accuracy of two previously validated prostate cancer risk predictors on biopsy.
Patients And Methods:
In total, 390 consecutive patients submitted to 10-core systematic transrectal prostate biopsy at our institution were included in this retrospective study. External validation of a European (European Randomized Study of Screening for Prostate Cancer derived Prostate Risk Indicator; SWOP-PRI) and a North American (Prostate Cancer Prevention Trial Cancer Risk Calculator; PCPT-CRC) nomogram was performed. The predictive accuracy of these online available nomograms was calculated based on the area under the curve derived from receiver-operator characteristic curves and then compared using the DeLong method.
Results:
Both tools were confirmed to be superior to prostate-specific antigen alone. Moreover, the SWOP-PRI (77.9%) displays a 7.96% increase in the predictive accuracy compared to the PCPT-CRC (69.9%) in a statistically significant fashion (P=0.002).
Conclusions:
The results obtained in the present study confirm the utility of nomograms with respect to biopsy outcome prediction in patients with suspicion of prostate cancer. In the current sample of patients, the European-based nomogram appears to be more accurate than the North American nonogram, which lacks information regarding prostate volume and prostatic ultrasonographic lesions. • To our knowledge, this is the first study to compare the accuracy of these popular risk calculators in a specific population.
