Introducing a prognostic score for pretherapeutic assessment of seminal vesicle invasion in patients with clinically localized prostate cancer

Histogram analysis of MR quantitative parameters: are they correlated with prognostic factors in prostate cancer?

PURPOSE

To investigate the correlation between quantitative MR parameters and prognostic factors in prostate cancer (PCa).

METHOD

A total of 186 patients with pathologically confirmed PCa who underwent preoperative multiparametric MRI (mpMRI), including synthetic MRI (SyMRI), were enrolled from two medical centers. The histogram metrics of SyMRI [T1, T2, proton density (PD)] and apparent diffusion coefficient (ADC) values were extracted. The Mann‒Whitney U test or Student's t test was employed to determine the association between these histogram features and the prognostically relevant factors. Receiver operating characteristic (ROC) curve analysis was conducted to evaluate the differentiation performance. Spearman's rank correlation coefficients were calculated to determine the correlations between histogram parameters and the International Society of Urological Pathology (ISUP) grade group as well as pathological T stage.

RESULTS

Significant correlations were found between the histogram parameters and the ISUP grade as well as pathological T stage of PCa. Among these histogram parameters, ADC_minimum had the strongest correlation with the ISUP grade (r = - 0.481, p < 0.001), and ADC_Median showed the strongest association with pathological T stage (r = - 0.285, p = 0.008). The ADC_10th percentile exhibited the highest performance in identifying clinically significant prostate cancer (csPCa) (AUC 0.833; 95% CI 0.771-0.883). When discriminating between the status of different prognostically relevant factors, a significant difference was observed between extraprostatic extension-positive and -negative cancers with regard to histogram parameters of the ADC map (10th percentile, 90th percentile, mean, median, minimum) and T1 map (minimum) (p = 0.002-0.032). Moreover, histogram parameters of the ADC map (90th percentile, maximum, mean, median), T2 map (10th percentile, median), and PD map (10th percentile, median) were significantly lower in PCa with perineural invasion (p = 0.009-0.049). The T2 values were significantly lower in patients with seminal vesicle invasion (minimum, p = 0.036) and positive surgical margin (10th percentile, 90th percentile, mean, median, and minimum, p = 0.015-0.025).

CONCLUSION

Quantitative histogram parameters derived from synthetic MRI and ADC maps may have great potential for predicting the prognostic features of PCa.

An external validation of the Candiolo nomogram in a cohort of prostate cancer patients treated by external-beam radiotherapy

Background

the aim of this study is to perform an external validation for the Candiolo nomogram, a predictive algorithm of biochemical and clinical recurrences in prostate cancer patients treated by radical Radiotherapy, published in 2016 on the journal “Radiation Oncology”.

Methods

561 patients, treated by Radiotherapy with curative intent between 2003 and 2012, were classified according to the five risk-classes of the Candiolo nomogram and the three risk-classes of the D’Amico classification for comparison. Patients were treated with a mean prostatic dose of 77.7 Gy and a combined treatment with Androgen-Deprivation-Therapy in 76% of cases. The end-points of the study were biochemical-progression-free-survival (bPFS) and clinical-Progression-Free-Survival (cPFS). With a median follow-up of 50 months, 56 patients (10%) had a biochemical relapse, and 30 patients (5.4%) a clinical progression. The cases were divided according to D’Amico in low-risk 21%, intermediate 40%, high-risk 39%; according to Candiolo very-low-risk 24%, low 37%, intermediate 24%, high 10%, very-high-risk 5%. Statistically, the Kaplan-Meier survival curves were processed and compared using Log-Rank tests and Harrell-C concordance index.

Results

The 5-year bPFS for the Candiolo risk-classes range between 98 and 38%, and the 5-year cPFS between 98 and 50% for very-low and very-high-risk, respectively. The Candiolo nomogram is highly significant for the stratification of both bPFS and cPFS (P < 0.0001), as well as the D’Amico classification (P = 0.004 and P = 0.001, respectively). For the Candiolo nomogram, the C indexes for bPFS and cPFS are 75 and 80%, respectively, while for D’Amico classification they are 64 and 69%, respectively. The Candiolo nomogram can identify a greater number of patients with low and very-low-risk prostate cancer (61% versus 21% according to D’Amico) and it better picks out patients with high and very-high-risk of recurrence, equal to only 15% of the total cases but subject to 48% (27/56) of biochemical relapses and 63% (19/30) of clinical progressions.

Conclusions

the external validation of the Candiolo nomogram was overall successful with C indexes approximately 10% higher than the D’Amico control classification for bPFS and cPFS. Therefore, its clinical use is justified in prostate cancer patients before radical Radiotherapy.

Trial registration Retrospectively registered.

[Seminal vesicle biopsies: Interest in the prostate cancer staging before radiation therapy or brachytherapy]

OBJECTIVE

Seminal vesicle biopsies (SVB) in the staging of prostate cancer are controversial. Our main objective was to assess their contribution before radiation therapy or brachytherapy. Our secondary objective was to compare pathologic findings of the SVB to the magnetic resonance imaging's (MRI) results.

PATIENTS AND METHODS

From 2000 to 2008, 135 men (median age: 70 years) with prostate cancer (cT1a to cT3) underwent SVB right and left. The median PSA was 12 ng/ml. The median Gleason score was 7. Forty-one patients had an endorectal MRI. The median follow-up was 47 months.

RESULTS

Seminal vesicle involvement was found in 10% of patients. In 9.2% of cases, the biopsy was not contributive. The risk of invasion was significantly associated with the stage T3, the Gleason score up to 7 and the percentage of prostate positive biopsies. A MRI was performed in 41 cases: the correlation between MRI and SVB for the invasion of seminal vesicle was significant but moderate (kappa=0.38). The complications rate of SVB was 10%.

CONCLUSION

SVB were a simple and profitable method. They have provided supplementary information that could improve the staging and that could lead to the make use of an appropriate treatment. This information was comparable to the information provided by MRI. Further studies should establish their role in relation to MRI and in particular confirm the best specificity of the SVB.

Is seminal vesiculectomy necessary in all patients with biopsy Gleason score 6?

BACKGROUND AND PURPOSE

Radiotherapists are excluding the seminal vesicles (SVs) from their target volume in cases of low-risk prostate cancer. However, these glands are routinely removed in every radical prostatectomy. Dissection of the SVs can damage the pelvic plexus, compromise trigonal, bladder neck, and cavernosal innervation, and contribute to delayed gain of continence and erectile function. In this study we evaluated the oncological benefit of routine removal of the SVs in currently operated patients.

MATERIALS AND METHODS

A total of 1003 patients (mean age, 59.7 years) with prostate cancer underwent robot-assisted radical prostatectomy between February 2003 and July 2007.

RESULTS

Seminal vesicle invasion (SVI) was found in 46 of the operated patients (4.6%). Biopsy Gleason score (BGS), preoperative serum PSA, clinical tumor stage, percent of positive cores, and maximal percentage of cancer in a core had all a significant impact on the risk of SVI. Only 4/634 patients (0.6%) with BGS < or =6 suffered from SVI, as opposed to 42/369 (11.4%) with higher Gleason scores.

CONCLUSIONS

Seminal vesiculectomy does not benefit more than 99% of the patients with BGS < or =6. Considering the potential neural and vascular damage associated with seminal vesiculectomy, we suggest that routine removal of these glands during radical prostatectomy in these cases is not necessary.

When should the seminal vesicles be included in the target volume in prostate radiotherapy?

External beam radiotherapy to the prostate and seminal vesicles as a radical treatment for prostate cancer can result in a significant dose being delivered to the rectum. This can be reduced if the target volume includes the prostate only. Using a Medline search, published studies are reviewed to show that the risk of seminal vesicle involvement can be accurately predicted using readily available pre-treatment parameters. We recommend when to exclude the seminal vesicles from a target volume, and the proportion of seminal vesicles that should be included in a target volume in higher risk patients.

Complete Resection of Seminal Vesicles at Radical Prostatectomy Results in Substantial Long-Term Disease-Free Survival: Multi-institutional Study of 6740 Patients

OBJECTIVES

To estimate the disease-specific survival of patients with complete removal of the seminal vesicles (SVs) at radical prostatectomy and to develop a nomogram for the prediction of SV invasion (SVI).

METHODS

An analysis of 6740 patients from three institutions was performed. The primary outcome was biochemical failure analyzed according to the presence or absence of SVI using the Kaplan-Meier method and Cox proportional hazards model. The variables analyzed included age, biopsy Gleason score, clinical T stage, margin status, extracapsular extension, SVI, surgical Gleason score, initial prostate-specific antigen level, and institution. Logistic regression analysis was used to determine the preoperative factors predicting for SVI and create the model for the nomogram.

RESULTS

Of the 6740 patients, 566 (8.4%) had positive SVs. The median follow-up was 33.4 months (range 1 to 239). The 5 and 10-year biochemical relapse-free survival rate was 38.0% and 25.6%, respectively, for patients with positive SVs and 85.7% and 77.2%, respectively, for patients with negative SVs (P <0.0001). In the multivariate model, all variables, except for biopsy Gleason score and T stage, were significant predictors of biochemical failure (P <0.05), and all variables, except for age, were predictors of SVI. The nomogram achieved an area under the curve of 0.80.

CONCLUSIONS

These results have demonstrated that a substantial number of patients with SVI are disease free at 5 and 10 years after complete excision without adjuvant therapy. These findings suggest the therapeutic efficacy of complete SV excision and can identify those with a nomogram-predicted increased risk of SVI who might benefit from complete excision.

Predictors of seminal vesicle invasion before radical prostatectomy

AIM

To predict whether or not seminal vesicle invasion is present before radical prostatectomy, the relationships between clinical parameters and seminal vesicle invasion were analyzed.

METHODS

A review was conducted of 187 patients who had been clinically diagnosed with stages A(2), B(0), B(1), B(2) or C prostate cancer and who had undergone radical prostatectomy without neoadjuvant therapy. The parameters analyzed for potential predictors of seminal vesicle invasion before radical prostatectomy included age, clinical stage, serum prostate-specific antigen (PSA) level at biopsy, tumor differentiation of biopsy specimens and percentage of cancer positive cores by biopsy. For percentage of cancer positive cores by biopsy, 143 of 187 patients who underwent transrectal sextant biopsy or more than six transrectal ultrasound guided core biopsies were evaluated. These parameters were subjected to univariate and multivariate logistic regression analyses to identify predictors for seminal vesicle invasion.

RESULTS

The median age was 66.8 years (range 51-77 years). Of 187 patients, 27 (14.4%) had seminal vesicle invasion confirmed pathologically. There were significant differences in all parameters except for age between patients with positive and negative seminal vesicle invasion on univariate analysis. Multivariate analysis revealed that serum PSA level, tumor differentiation of biopsy specimens and percentage of cancer positive cores were significant independent predictors of seminal vesicle invasion.

CONCLUSIONS

The results showed serum PSA level, tumor differentiation of biopsy specimens and percentage of cancer positive cores by biopsy before radical prostatectomy may be useful predictors for seminal vesicle invasion.

Endorectal MR Imaging in the Evaluation of Seminal Vesicle Invasion: Diagnostic Accuracy and Multivariate Feature Analysis

PURPOSE

To retrospectively determine the accuracy of endorectal magnetic resonance (MR) imaging in demonstrating seminal vesicle invasion (SVI) and to investigate the MR imaging features that can predict SVI.

MATERIALS AND METHODS

The Institutional Review Board granted exempt status for this retrospective study, with waiver of informed consent; patient data were collected and handled in accordance with HIPAA regulations. Fifty-one men (age range, 44-73 years) with SVI and 303 men (age range, 40-76 years) without SVI who underwent endorectal MR imaging before radical prostatectomy between January 2000 and October 2004 were included in the study. Endorectal MR images were retrospectively and independently analyzed by two radiologists for SVI, tumor at prostate base, extracapsular extension, and other features considered indicative of SVI. Areas under the receiver operating characteristic curves (AUCs) were used to assess the accuracy of detecting SVI at endorectal MR imaging. A multiple logistic regression was used to explore the combinations of MR imaging features that might facilitate the detection of SVI.

RESULTS

Readers 1 and 2 had an AUC of 0.93 and 0.81, respectively, for the detection of SVI. For both readers, the features that had the highest sensitivity and specificity were low signal intensity within the seminal vesicle and lack of preservation of seminal vesicle architecture. At multiple regression analysis, tumor at the prostate base that extended beyond the capsule and low signal intensity within a seminal vesicle that has lost its normal architecture were highly predictive of SVI.

CONCLUSION

Endorectal MR imaging is accurate in demonstrating SVI prior to radical prostatectomy, and recognition of the most predictive features may facilitate the use of this modality.

The GETUG 70 Gy vs. 80 Gy randomized trial for localized prostate cancer: feasibility and acute toxicity

PURPOSE

To describe treatments and acute tolerance in a randomized trial comparing 70 Gy and 80 Gy to the prostate in patients with localized prostate cancer.

METHODS AND MATERIALS

Between September 1999 and February 2002, 306 patients were randomized to receive 70 Gy (153 patients) or 80 Gy (153 patients) in 17 institutions. Patients exhibited intermediate-prognosis tumors. If the risk of node involvement was greater than 10%, surgical staging was required. Previous prostatectomy was excluded, and androgen deprivation was not admitted. The treatment was delivered in two steps. PTV1-including seminal vesicles, prostate, and a 1-0.5-cm margin-received 46 Gy given with a 4-field conformal technique. PTV2, reduced to prostate with the same margins, irradiated with at least 5 fields. Dose was prescribed according to ICRU recommendations in the 70 Gy group, but adapted at the 80 Gy level.

RESULTS

All patients but one in the 80 Gy arm completed the treatment. In the 70 Gy arm, the mean dose to the PTV2 was 69.5 Gy. In the 80 Gy arm, the mean dose in the PTV2 was 78.5 Gy. Acute toxicity according to Radiation Therapy Oncology Group scale during treatment was reported in 306 patients. There was no statistically significant difference between the two arms: 12% had no toxicity, 80% complained of bladder toxicity, and 70% complained of rectal symptoms. Two months after the end of treatment, 43% of the 70 Gy level and 48% of the 80 Gy level complained of side effects, including 24% and 20% of sexual disorders. There was 6% and 2% of Grade 3 urinary and rectal toxicity. Five patients required a 10-29-day suspension of the treatment. Acute Grade 2 and 3 side effects were related to PTV and CTV1 size, which was the only independent predictive factor in multivariate analysis. Toxicity was not related to the center, age, arm of treatment, or selected data from dose-volume histogram of organ at risk.

CONCLUSION

Treatments were completed in respect to constraints. Acute toxicity was acceptable. Intensity of toxicity depended on target volumes.