Validation of 2001 Partin tables in Turkey: a multicenter study

Prediction of pathological stage based on clinical stage, serum prostate-specific antigen, and biopsy Gleason score: Partin Tables in the contemporary era

OBJECTIVE

To update the Partin Tables for prediction of pathological stage in the contemporary setting and examine trends in patients treated with radical prostatectomy (RP) over the past three decades.

PATIENTS AND METHODS

From January 2010 to October 2015, 4459 men meeting inclusion criteria underwent RP and pelvic lymphadenectomy for histologically confirmed prostate cancer at the Johns Hopkins Hospital. Preoperative clinical stage, serum prostate-specific antigen (PSA) level, and biopsy Gleason score (i.e. prognostic Grade Group) were used in a polychotomous logistic regression model to predict the probability of pathological outcomes categorised as: organ-confined (OC), extraprostatic extension (EPE), seminal vesicle involvement (SV+), or lymph node involvement (LN+). Preoperative characteristics and pathological findings in men treated with RP since 1983 were collected and clinical-pathological trends were described.

RESULTS

The median (range) age at surgery was 60 (34-77) years and the median (range) PSA level was 4.9 (0.1-125.0) ng/mL. The observed probabilities of pathological outcomes were: OC disease in 74%, EPE in 20%, SV+ in 4%, and LN+ in 2%. The probability of EPE increased substantially when biopsy Gleason score increased from 6 (Grade Group 1, GG1) to 3 + 4 (GG2), with smaller increases for higher grades. The probability of LN+ was substantially higher for biopsy Gleason score 9-10 (GG5) as compared to lower Gleason scores. Area under the receiver operating characteristic curves for binary logistic models predicting EPE, SV+, and LN+ vs OC were 0.724, 0.856, and 0.918, respectively. The proportion of men treated with biopsy Gleason score ≤6 cancer (GG1) was 47%, representing a substantial decrease from 63% in the previous cohort and 77% in 2000-2005. The proportion of men with OC cancer has remained similar during that time, equalling 73-74% overall. The proportions of men with SV+ (4.1% from 3.4%) and LN+ (2.3% from 1.4%) increased relative to the preceding era for the first time since the Partin Tables were introduced in 1993.

CONCLUSIONS

The Partin Tables remain a straightforward and accurate approach for projecting pathological outcomes based on readily available clinical data. Acknowledging these data are derived from a tertiary care referral centre, the proportion of men with OC disease has remained stable since 2000, despite a substantial decline in the proportion of men with biopsy Gleason score 6 (GG1). This is consistent with the notion that many men with Gleason score 6 (GG1) disease were over treated in previous eras.

An updated prostate cancer staging nomogram (Partin tables) based on cases from 2006 to 2011

OBJECTIVE

To update the 2007 Partin tables in a contemporary patient population.

PATIENTS AND METHODS

The study population consisted of 5,629 consecutive men who underwent RP and staging lymphadenectomy at the Johns Hopkins Hospital between January 1, 2006 and July 30, 2011 and met inclusion criteria. Polychotomous logistic regression analysis was used to predict the probability of each pathologic stage category: organ-confined disease (OC), extraprostatic extension (EPE), seminal vesicle involvement (SV+), or lymph node involvement (LN+) based on preoperative criteria. Preoperative variables included biopsy Gleason score (6, 3+4, 4+3, 8, and 9-10), serum PSA (0-2.5, 2.6-4.0, 4.1-6.0, 6.1-10.0, greater than 10.0 ng/mL), and clinical stage (T1c, T2c, and T2b/T2c). Bootstrap re-sampling with 1000 replications was performed to estimate 95% confidence intervals for predicted probabilities of each pathologic state.

RESULTS

The median PSA was 4.9 ng/mL, 63% had Gleason 6 disease, and 78% of men had T1c disease. 73% of patients had OC disease, 23% had EPE, 3% had SV+ but not LN+, and 1% had LN+ disease. Compared to the previous Partin nomogram, there was no change in the distribution of pathologic state. The risk of LN+ disease was significantly higher for tumours with biopsy Gleason 9-10 than Gleason 8 (O.R. 3.2, 95% CI 1.3-7.6). The c-indexes for EPE vs. OC, SV+ vs. OC, and LN+ vs. OC were 0.702, 0.853, and 0.917, respectively. Men with biopsy Gleason 4+3 and Gleason 8 had similar predicted probabilities for all pathologic stages. Most men presenting with Gleason 6 disease or Gleason 3+4 disease have <2% risk of harboring LN+ disease and may have lymphadenectomy omitted at RP.

CONCLUSIONS

The distribution of pathologic stages did not change at our institution between 2000-2005 and 2006-2011. The updated Partin nomogram takes into account the updated Gleason scoring system and may be more accurate for contemporary patients diagnosed with prostate cancer.

The need for, and utilization of prostate-bed radiotherapy after radical prostatectomy for patients with prostate cancer in British Columbia

INTRODUCTION

Three randomized trials have demonstrated that post-radical prostatectomy (RP) radiotherapy decreases biochemical relapse for those with adverse pathology. Our purpose was to describe the incidence of pathologic risk factors for recurrence in a contemporary series of patients treated with RP and to describe the use of post-RP radiotherapy.

METHODS

All incident prostate cancers diagnosed between January 2005 and December 2007 were identified from the tumour registry. Cases were then linked to radiotherapy records which included dose and modality (external beam radiotherapy and brachytherapy). The pathology reports in the tumour registry were reviewed for pathologic stage, grade and margin status.

RESULTS

We identified 9223 patients with prostate cancer. Overall, 36.3% of patients treated with RP had positive margins, and may have benefited from adjuvant radiotherapy. After RP, 332 (15%) patients had radiotherapy to the prostate bed; of these, only 25 (1.1%) received truly adjuvant radiotherapy (delivered within 6 months with a prostate-specific antigen of <0.2 ng/mL). Of the 2181 patients treated with RP, 270 (12%) were seen by a radiation oncologist within 6 months of RP. Of the 1015 patients (47%) with adverse RP pathology (positive margins, extracapsular extension or seminal vesicle invasion), 230 (23%) were seen by a radiation oncologist within 6 months of RP.

CONCLUSION

Not all patients with adverse prostatectomy pathology were seen by a radiation oncologist post-prostatectomy, and very few received adjuvant radiotherapy despite almost half of them having risk factors for relapse.

Is primary prostate cancer treatment influenced by likelihood of extraprostatic disease? A surveillance, epidemiology and end results patterns of care study

PURPOSE

To examine the patterns of primary treatment in a recent population-based cohort of prostate cancer patients, stratified by the likelihood of extraprostatic cancer as predicted by disease characteristics available at diagnosis.

METHODS AND MATERIALS

A total of 157,371 patients diagnosed from 2004 to 2008 with clinically localized and potentially curable (node-negative, nonmetastatic) prostate cancer, who have complete information on prostate-specific antigen, Gleason score, and clinical stage, were included. Patients with clinical T1/T2 disease were grouped into categories of <25%, 25%-50%, and >50% likelihood of having extraprostatic disease using the Partin nomogram. Clinical T3/T4 patients were examined separately as the highest-risk group. Logistic regression was used to examine the association between patient group and receipt of each primary treatment, adjusting for age, race, year of diagnosis, marital status, Surveillance, Epidemiology and End Results database region, and county-level education. Separate models were constructed for primary surgery, external-beam radiotherapy (RT), and conservative management.

RESULTS

On multivariable analysis, increasing likelihood of extraprostatic disease was significantly associated with increasing use of RT and decreased conservative management. Use of surgery also increased. Patients with >50% likelihood of extraprostatic cancer had almost twice the odds of receiving prostatectomy as those with <25% likelihood, and T3-T4 patients had 18% higher odds. Prostatectomy use increased in recent years. Patients aged 76-80 years were likely to be managed conservatively, even those with a >50% likelihood of extraprostatic cancer (34%) and clinical T3-T4 disease (24%). The proportion of patients who received prostatectomy or conservative management was approximately 50% or slightly higher in all groups.

CONCLUSIONS

There may be underutilization of RT in older prostate cancer patients and those with likely extraprostatic disease. Because more than half of prostate cancer patients do not consult with a radiation oncologist, a multidisciplinary consultation may affect the treatment decision-making process.

Machine learning for improved pathological staging of prostate cancer: a performance comparison on a range of classifiers

OBJECTIVES

Prediction of prostate cancer pathological stage is an essential step in a patient's pathway. It determines the treatment that will be applied further. In current practice, urologists use the pathological stage predictions provided in Partin tables to support their decisions. However, Partin tables are based on logistic regression (LR) and built from US data. Our objective is to investigate a range of both predictive methods and of predictive variables for pathological stage prediction and assess them with respect to their predictive quality based on U.K. data.

METHODS AND MATERIAL

The latest version of Partin tables was applied to a large scale British dataset in order to measure their performances by mean of concordance index (c-index). The data was collected by the British Association of Urological Surgeons (BAUS) and gathered records from over 1700 patients treated with prostatectomy in 57 centers across UK. The original methodology was replicated using the BAUS dataset and evaluated using concordance index. In addition, a selection of classifiers, including, among others, LR, artificial neural networks and Bayesian networks (BNs) was applied to the same data and compared with each other using the area under the ROC curve (AUC). Subsets of the data were created in order to observe how classifiers perform with the inclusion of extra variables. Finally a local dataset prepared by the Aberdeen Royal Infirmary was used to study the effect on predictive performance of using different variables.

RESULTS

Partin tables have low predictive quality (c-index=0.602) when applied on UK data for comparison on patients with organ confined and extra prostatic extension conditions, patients at the two most frequently observed pathological stages. The use of replicate lookup tables built from British data shows an improvement in the classification, but the overall predictive quality remains low (c-index=0.610). Comparing a range of classifiers shows that BNs generally outperform other methods. Using the four variables from Partin tables, naive Bayes is the best classifier for the prediction of each class label (AUC=0.662 for OC). When two additional variables are added, the results of LR (0.675), artificial neural networks (0.656) and BN methods (0.679) are overall improved. BNs show higher AUCs than the other methods when the number of variables raises

CONCLUSION

The predictive quality of Partin tables can be described as low to moderate on U.K. data. This means that following the predictions generated by Partin tables, many patients would received an inappropriate treatment, generally associated with a deterioration of their quality of life. In addition to demographic differences between U.K. and the original U.S. population, the methodology and in particular LR present limitations. BN represents a promising alternative to LR from which prostate cancer staging can benefit. Heuristic search for structure learning and the inclusion of more variables are elements that further improve BN models quality.

Validation of two preoperative Kattan nomograms predicting recurrence after radical prostatectomy for localized prostate cancer in Turkey: a multicenter study of the Uro-oncology Society

OBJECTIVES

To examine, in a multicenter validation study designed under the guidance of the Uro-Oncology Society, the predictive accuracies of the 1998 and 2006 Kattan preoperative nomograms in Turkish patients. These 2 preoperative Kattan nomograms use preoperative parameters to estimate disease recurrence after radical prostatectomy.

METHODS

A total of 1261 men with clinically localized prostate cancer undergoing radical prostatectomy were included. The preoperative prostate-specific antigen level, biopsy Gleason score, clinical stage, number of positive and negative prostate biopsy cores, and postoperative recurrence status of all patients were studied. The predicted values using the Kattan nomograms and the observed values were compared.

RESULTS

The patient characteristics in the cohort were comparable with those of the cohorts used to create the Kattan nomograms. The 5-year probability of freedom from recurrence was 73% using Kaplan-Meier analysis and was similar to that of the 1998 Kattan nomogram cohort. However, the 10-year probability of freedom from recurrence was 67%, slightly lower than the same estimate from the 2006 nomogram cohort. The predicted values of recurrence using Kattan nomogram and the observed rates in our cohort were similar. The estimated concordance index value was 0.698 and 0.705 for 1998 and 2006 nomograms, respectively.

CONCLUSIONS

The Kattan preoperative nomograms can be used with adequate success in Turkey, because the predicted and observed rates in our cohort were similar. Our results have demonstrated satisfactory concordance index values, suggesting that both the 1998 and the 2006 Kattan preoperative nomograms can safely be used in Turkish patients with similar accuracy. Although the 2006 nomogram had slightly better discrimination, the 1998 nomogram was a little more calibrated.

Percentage of tumour-positive biopsy cores: an independent predictor of extraprostatic disease

OBJECTIVE

Preoperative staging of patients diagnosed with prostate cancer is vital in determining the correct treatment including radical prostatectomy. Serum prostate-specific antigen (PSA), Gleason score in prostate biopsies and predicted clinical T-stage using digital rectal examination and transrectal ultrasound are known predictors of extraprostatic disease after surgery. This study analysed whether the percentage of positive biopsy cores was a significant preoperative predictor of extraprostatic disease in patients undergoing radical prostatectomy.

MATERIAL AND METHODS

An analysis was conducted on 390 consecutive patients who underwent radical prostatectomy at Arhus University hospital from 2000 to 2006. Serum PSA, Gleason score, predicted clinical T-stage and percentage of positive biopsy cores were tested in a univariate analysis, and then a multivariate logistical regression model, to determine whether they were predictors of extraprostatic disease.

RESULTS

The percentage of positive biopsy cores was, together with T-stage and Gleason score, shown to be a significant predictor of extraprostatic disease in both univariate and multivariate analysis with a p-value of 0.05. The calculation yields a model that can predict risk of non-organ-confined disease in a non-screened population.

CONCLUSION

Being an independent predictor of extraprostatic disease, the percentage of positive biopsy cores can supplement existing preoperative staging variables as found in current staging nomograms.

Updated nomogram to predict pathologic stage of prostate cancer given prostate-specific antigen level, clinical stage, and biopsy Gleason score (Partin tables) based on cases from 2000 to 2005

OBJECTIVES

To update the 2001 "Partin tables" with a contemporary patient cohort and revised variable categorization, correcting for the effects of stage migration.

METHODS

We analyzed 5730 men treated with prostatectomy (without neoadjuvant therapy) between 2000 and 2005 at the Johns Hopkins Hospital. Average age was 57 years. Multivariable logistic regression was used to estimate the probability of organ-confined disease, extraprostatic extension, seminal vesicle involvement, or lymph node involvement. Predictor variables included preoperative prostate-specific antigen (PSA) level (0 to 2.5, 2.6 to 4.0, 4.1 to 6.0, 6.1 to 10.0, and greater than 10.0 ng/mL), clinical stage (T1c, T2a, and T2b/T2c), and biopsy Gleason score (5 to 6, 3 + 4 = 7, 4 + 3 = 7, or 8 to 10). Bootstrap resampling was used to generate 95% confidence intervals for predicted probabilities.

RESULTS

Seventy-seven percent of patients had T1c, 76% had Gleason score 5 to 6, 80% had a PSA level between 2.5 and 10.0 ng/mL, and 73% had organ-confined disease. Nomograms were developed for the predicted probability of pathologically organ-confined disease, extraprostatic extension, seminal vesicle invasion, or lymph node involvement. The risk of non-organ-confined disease increased with increases in any individual prognostic factor. The dramatic decrease in clinical stage T2c compared with the patient series used in the previous models resulted in T2b and T2c being combined as a single predictor in the nomogram.

CONCLUSIONS

These updated "Partin tables" were generated to reflect trends in presentation and pathologic stage for men diagnosed with clinically localized prostate cancer at our institution. Clinicians and patients can use these nomograms to help make important decisions regarding management of prostate cancer.

A cadaveric histological investigation of the prostate with three-dimensional reconstruction for better results in continence and erectile function after radical prostatectomy

In this study our aim is to increase the understanding of the prostate and related organs anatomy for better continence and erectile function results after urological surgery. Prostate and related organs were dissected from seven cadavers. After dissection, 165 serial sections with 300 microm thickness were derived at a 100 microm interval. The histological images were examined and imported to the computer. Three-dimensional (3D) remodeling had been performed. The findings were evaluated into three categories: macroscopic, microscopic and 3D reconstruction. Striated muscle fibers had been detected at the anterior fibromuscular stroma in histological sections. In 3D remodeling, urethra seemed to be a complete functional unit, beginning from the trigone up to the membranous urethra. The neurovascular bundles run under the pelvic fascia on both sides and go through to the bladder neck at 5 and 7 o'clock. Computer remodeling demonstrated that neurovascular structures had a close association with the bladder neck and the seminal vesicle. Computer program made it possible to rotate all 3D-reconstructed figures by 360 degrees and examine them from all possible angles. All reconstructed structures can be examined together at the same time or one by one. Surgeons must pay special attention to the continence area described as a single unit, beginning from trigone to the membranous urethra, during the surgery. Meticulous dissection of the neurovascular bundles, especially close to the seminal vesicles and bladder neck, during the radical prostatectomy is necessary. These reconstructions can be used for the educational purpose of medical students as well as the urology surgeons.

The effect of prior biopsy scheme on prostate cancer detection for repeat biopsy population: results of the 14-core prostate biopsy technique

OBJECTIVES

To evaluate the diagnostic performance of 14-core repeat biopsy protocol and the impact of prior biopsy scheme on repeat prostate biopsy group.

METHODS

211 patients had repeat biopsy using 14-core protocol consisting of 10-core peripheral zone (classical sextant+4 lateral peripheral cores) and 4-core transitional zone (TZ) biopsies. The diagnostic yield was determined both in patients who had previously undergone sextant or 10-core biopsy protocol.

RESULTS

Overall cancer detection rate was 25.6%. 14-core biopsy technique detected cancer in 36.1 and 18.7% of the patients who had a previous sextant biopsy and 10-core biopsy protocol, respectively (P = 0.005). Patients with and without high-grade prostatic intraepithelial neoplasia (HGPIN) in the previous sextant biopsy had 56.5 and 28.3% cancer detection rates on the subsequent extended biopsy, respectively (P = 0.017) Patients who had previous 10-core biopsy with and without HGPIN revealed 22.9 and 17.2% cancer detection rates, respectively (P = 0.465) Additional four lateral peripheral cores detected 33% (3/30) and 17% (4/24) of cancers in patients with previous sextant and 10-core biopsy, respectively. 3.7% of the patients had tumor only in the TZ and none of them had prior extended biopsy.

CONCLUSIONS

The yield of extended 14-core repeat biopsy protocol was higher in patients with previous negative sextant biopsy compared to the patients with previous negative 10-core biopsy. HGPIN history found on previous sextant biopsy was a strong cancer predictor on repeat biopsy; same was not true for the patients with previous 10-core biopsy. The yield of lateral peripheral cores and TZ biopsies were lower in patients with prior negative extended biopsy.

Predictive Ability of Partin Tables 2001 in a Welsh Population

OBJECTIVES

Partin tables are widely used to select and counsel patients prior to radical surgery for prostate cancer. However, Partin tables have been developed in the USA which has a different ethnic mixture from that of North Wales. We aimed to assess Partin tables' predictive ability in a Welsh population.

MATERIALS AND METHODS

193 patients underwent radical retropubic prostatectomy for clinically localized carcinoma of the prostate between April 1993 and July 2004 in a single institution in North Wales. Complete preoperative clinical staging information was available in 177 patients. Receiver operating characteristic curve analysis was used.

RESULTS

The mean patient age was 64 (48-73) years. Preoperative clinical staging distribution was: T1c 46.6% and T2 53.4%. 75% had organ-confined disease (TNM 1992). Extracapsular extension without seminal vesicle or lymph node involvement was seen in 13.5%. Nine percent had seminal vesicle invasion without lymph node involvement. Lymph node metastasis was found in 2.2%. The predictive effectiveness of the Partin table was high with an area under ROC curve of 0.733 for organ confinement, 0.738 for seminal vesicle invasion and 0.780 for lymph node involvement (CI 95%).

CONCLUSION

Our study demonstrated that the predictive ability of Partin tables for prostate cancer is also applicable to a Welsh population.

INDIVIDUALIZATION OF THE BIOPSY PROTOCOL ACCORDING TO THE PROSTATE GLAND VOLUME FOR PROSTATE CANCER DETECTION

PURPOSE

In this study we assessed the relative yield of 10 core biopsy, and the whole range of alternative 8 and 6 core biopsy protocols over that of the classic sextant biopsy protocol. We determined the optimum number of cores per biopsy according to prostate volume in patients who experienced prostate biopsy for the first time.

MATERIALS AND METHODS

A total of 503 men with the indications of abnormal digital rectal examination and/or serum prostate specific antigen greater than 2.5 ng/ml were included in the study. All patients underwent a 10 core biopsy protocol with an additional 1 core from each suspicious area detected by transrectal ultrasound. Prostate volume was divided into quartiles, namely 14.9 to 35, 35.1 to 50, 50.1 to 65 and 65.1 to 150 cc. The optimum number of biopsy cores was determined in patients with different prostate volumes.

RESULTS

Median age was 63 years and prostate specific antigen was 7.4 ng/ml in the whole group. Of 503 patients 159 (31.6%) were positive for prostate cancer. Cancer detection rates decreased significantly from 49.6% to 20.8% as prostate volume increased in preset quartiles. Lesion biopsies revealed the lowest unique cancer detection rates for all prostate volume quartiles (0% to 3%). There was an obvious positive trend in cancer detection rates in favor of the 10 core biopsy protocol over sextant biopsies in all patient groups. Classic sextant biopsy protocol proved to be inadequate for all prostate volumes. Among sextant biopsy protocols laterally placed cores including the apex, lateral mid gland and lateral base had the best cancer detection rates (81% to 95%). The 8 core biopsy scheme consisting of the apex, mid gland, lateral mid gland and lateral base resulted in an only 1% lower detection rate (97%) than the 10 core biopsy protocol in the lowest quartile. The yield of the 10 core biopsy protocol in patients with a prostate volume of between 35.1 and 150 cc outscored that of the optimal 8 core biopsy scheme including the apex, base, lateral mid gland and lateral base with 3% to 8% differences in the cancer detection rate.

CONCLUSIONS

The 10 core biopsy protocol must be used in all group of patients except patients with a prostate volume of 14.9 to 35 cc. In patients with a prostate volume of 14.9 to 35 cc the 8 core biopsy protocol consisting of the apex, mid gland, lateral mid gland and lateral base can be used since it revealed results similar to those of the 10 core biopsy protocol. The classic sextant biopsy protocol seemed inadequate for all prostate volumes. Patients with a larger prostate had lower cancer detection rates. Transrectal ultrasound directed lesion biopsies may be omitted when using 10 core biopsy protocols since the yield of these biopsies was less than 2%.