Two Decades of Active Surveillance for Prostate Cancer in a Single-Center Cohort: Favorable Outcomes after Transurethral Resection of the Prostate

Long-term follow-up results of multiparametric prostate MRI and the prognostic value of PI-RADS: a single-center retrospective cohort study

PURPOSE

We aim to examine the long-term outcomes of patients who underwent multiparametric prostate magnetic resonance imaging (mp-MRI) for suspected prostate cancer (PCa), specifically based on their initial Prostate Imaging Reporting and Data System (PI-RADS) categories and various clinical factors. Our secondary aim is to evaluate the prognostic value of the PI-RADS through the National Comprehensive Cancer Network (NCCN) risk group distribution.

METHODS

This research was conducted as a single-center retrospective cohort study in a tertiary care hospital. A total of 1,359 cases having at least one histopathological examination after the initial mp-MRI and/or adequate clinical/radiological follow-up data were included in the clinically significant PCa (cs-PCa) diagnosis-free survival analysis. Initial mp-MRI dates were accepted as the start of follow-up for the time-to-event analysis. The event was defined as cs-PCa diagnosis (International Society of Urological Pathology ≥2). Patients who were not diagnosed with cs-PCa during follow-up were censored according to predefined literature-based criteria at the end of the maximum follow-up duration with no reasonable suspicion of PCa and no biopsy indication. The impact of various factors on survival was assessed using a log-rank test and multivariable Cox regression. Subsequently, 394 cases diagnosed with PCa during follow-up were evaluated, based on initial PI-RADS categories and NCCN risk groups.

RESULTS

Three main risk factors for cs-PCa diagnosis during follow-up were an initial PI-RADS 5 category, initial PI-RADS 4 category, and high MRI-defined PSA density (mPSAD), with average hazard ratios of 29.52, 14.46, and 3.12, respectively. The PI-RADS 3 category, advanced age group, and biopsy-naïve status were identified as additional risk factors (hazard ratios: 2.03, 1.54-1.98, and 1.79, respectively). In the PI-RADS 1-2 cohort, 1, 3, and 5-year cs-PCa diagnosis-free survival rates were 99.1%, 96.5%, and 93.8%, respectively. For the PI-RADS 3 cohort, 1, 3, and 5-year cs-PCa diagnosis-free survival rates were 94.9%, 90.9%, and 89.1%, respectively. For the PI-RADS 4 cohort, 1, 3, and 5-year cs-PCa diagnosis-free survival rates were 56.6%, 55.1%, and 55.1%, respectively. These rates were found to all be 24.2% in the PI-RADS 5 cohort. Considering the 394 cases diagnosed with PCa during follow-up, PI-RADS ≥4 cases were more likely to harbor unfavorable PCa compared to PI-RADS ≤3 cases (P < 0.001). In the PI-RADS 3 subgroup analysis, a low mPSAD (<0.15 ng/mL2) was found to be a protective prognostic factor against unfavorable PCa (P = 0.005).

CONCLUSION

The PI-RADS category has a significant impact on patient management and provides important diagnostic and prognostic information. Higher initial PI-RADS categories are associated with decreased follow-up losses, a shorter time to PCa diagnosis, increased biopsy rates, a higher likelihood of developing cs-PCa during follow-up, and a worse PCa prognosis. Combining mPSAD with PI-RADS categories could enhance diagnostic stratification in the identification of cs-PCa.

Propensity score-matched evaluation of palliative transurethral resection and holmium laser enucleation of the prostate for bladder outlet obstruction in patients with prostate cancer

BACKGROUND

While transurethral resection of the prostate (TURP) is the standard-of-care, Holmium laser enucleation of the prostate (HoLEP) is widely accepted as a size-independent method for surgical treatment of patients with lower urinary tract symptoms (LUTS) secondary to bladder outlet obstruction (BOO). However, in an ageing society an increasing number of patients presents with BOO due to locally advanced prostate cancer. There is currently no guidelines recommendation as to the enucleation or resection technique. Therefore, we compared intraoperative performance, postoperative outcomes, and safety for palliative (p)TURP and (p)HoLEP.

METHODS

We conducted a retrospective, propensity score-matched analysis of 1373 and 2705 men who underwent TURP or HoLEP for LUTS/BOO between 2014 and 2021, respectively. Patients were matched for age, prostate size and preoperative international prostate symptom score (IPSS). Patients were stratified by technique and groups were compared for perioperative parameters, safety, and functional outcomes.

RESULTS

While postoperative symptoms and urodynamic parameters improved irrespective of technique, we report significantly increased resection and enucleation times for palliative indication. For corresponding efficiency parameters, we observed a two-fold higher surgical performance (g/min) for both techniques in patients without prostate cancer. While adverse events were comparable between groups, we found a two-fold higher hemoglobin drop in palliative patients.

CONCLUSIONS

Currently, there is no standard-of-care for patients with BOO and locally advanced prostate cancer. Our data show that both TURP and HoLEP offer adequate symptom improvement and comparable safety profiles. While HoLEP is feasible even in larger prostates, both procedures become more difficult in patients with prostate cancer. Taken together, this study covers an important gap in current literature, helping urological surgeons to make evidence-based decisions for the benefit of their patients.

Characteristics of incidental prostate cancer in the United States

BACKGROUND

Data regarding North-American incidental (cT1a/b) prostate cancer (PCa) patients is scarce. To address this, incidental PCa characteristics (age, PSA values at diagnosis, Gleason score [GS]), subsequent treatment and cancer-specific survival (CSS) rates were explored.

METHODS

Incidental PCa patients were identified within the Surveillance, Epidemiology, and End Results (SEER) database (2004-2015). Descriptive statistics, annual percentage changes (EAPC), Kaplan-Meier estimates, as well as Cox regression models were used. Bootstrapping technique was used to generate 95% confidence intervals for CSS at 6 years.

RESULTS

Of all 344,031 newly diagnosed non metastatic PCa patients, 5155 harbored incidental PCa. Annual rates of incidental PCa increased from 1.9% (2004) to 2.5 % (2015; p = 0.02). PSA values at diagnosis were 0-4 ng/ml in 48% vs. 4-10 ng/ml in 31% vs. > 10 ng/ml in 21%. Of all incidental PCa patients, 64% harbored GS 6 vs. 25% GS 7 vs. 11% GS ≥ 8. Of all incidental PCa patients, 47% were aged < 70, 35% were between 70 and 79 and 18% were ≥ 80 years. Subsequently, 71% underwent no local treatment (NLT) vs. 16% radical prostatectomy (RP) vs. 14% radiotherapy (RT). Proportions of patients with NLT increased from 65 to 81% (p = 0.0001) over the study period (2004-2015). CSS at six years ranged from 58% in GS ≥ 8 patients with NLT to 100% in patients who harbored GS 6 and underwent either RP or RT.

CONCLUSION

Incidental PCa in the United States is rare. Most incidental PCa patients are diagnosed in men aged less than 80 years of age. The majority of incidental PCa patients undergo NLT and enjoy excellent CSS.

Current Trends in Incidence and Management of T1a and T1b Prostate Cancer

Prostate cancer (PCa) identified incidentally (iPCa) after surgical treatment for symptomatic benign prostatic hyperplasia (BPH) causing lower urinary tract symptoms (LUTS) is considered low risk by the most current guidelines. Management protocols for iPCa are conservative and are identical to other prostate cancers classified as having favorable prognoses. The objectives of this paper are to discuss the incidence of iPCa stratified by BPH procedure, to highlight predictors of cancer progression, and to propose potential modifications to mainstream guidelines for the optimal management of iPCa. The correlation between the rate of iPCa detection and the method of BPH surgery is not clearly defined. Old age, small prostate volume, and high pre-operative prostate-specific antigen (PSA) are associated with an increased likelihood of detecting iPCa. PSA and tumor grade are strong predictors of cancer progression and can be used along with magnetic resonance imaging (MRI) and potential confirmatory biopsies to determine disease management. In instances that iPCa requires treatment, radical prostatectomy (RP), radiation therapy, and androgen deprivation therapy all have oncologic benefits but may be associated with increased risk after the BPH surgery. It is advised that patients with low to favorable intermediate-risk prostate cancer undergo post-operative PSA measurement and prostate MRI imaging before electing to choose between observation, surveillance without confirmatory biopsy, immediate confirmatory biopsy, or active treatment. Subdividing the binary T1a/b cancer staging into more categories with ranging percentages of malignant tissue would be a helpful first step in tailoring the management of iPCa.

Ultra-Hypofractionated Stereotactic Body Radiotherapy for Localized Prostate Cancer: Clinical Outcomes, Patterns of Recurrence, Feasibility of Definitive Salvage Treatment, and Competing Oncological Risk

A cohort of 650 patients treated for localized prostate cancer (PCa) with CyberKnife^TM ultra-hypofractionated radiotherapy between 2011 and 2018 was retrospectively analyzed in terms of survival, patterns of failure, and outcomes of second-line definitive salvage therapies. The analysis was performed using survival analysis including the Kaplan-Meier method and Cox regression analysis. At a median follow-up of 49.4 months, the main pattern of failure was local-regional failure (7.4% in low-, and 13% in intermediate/high-risk group at five years), followed by distant metastases (3.6% in low-, and 6% in intermediate/high-risk group at five years). Five-year likelihood of developing a second malignancy was 7.3%; however, in the vast majority of the cases, the association with prior irradiation was unlikely. The 5-year overall survival was 90.2% in low-, and 88.8% in intermediate/high-risk patients. The independent prognostic factors for survival included age (HR 1.1; 95% CI 1.07-1.14) and occurrence of a second malignancy (HR 3.67; 95% CI 2.19-6.15). Definitive local salvage therapies were feasible in the majority of the patients with local-regional failure, and uncommonly in patients with distant metastases, with an estimated second-line progression free survival of 67.8% at two years. Competing oncological risks and age were significantly more important for patients' survival compared to primary disease recurrence.

The Economic Burden of Localized Prostate Cancer and Insights Derived from Cost-Effectiveness Studies of the Different Treatments

Prostate cancer has huge health and societal impacts, and there is no clear consensus on the most effective and efficient treatment strategy for this disease, particularly for localized prostate cancer. We have reviewed the scientific literature describing the economic burden and cost-effectiveness of different treatment strategies for localized prostate cancer in OECD countries. We initially identified 315 articles, studying 13 of them in depth (those that met the inclusion criteria), comparing the social perspectives of cost, time period, geographical area, and severity. The economic burden arising from prostate cancer due to losses in productivity and increased caregiver load is noticeable, but clinical decision-making is carried out with more subjective variability than would be advisable. The direct cost of the intervention was the main driver for the treatment of less severe cases of prostate cancer, whereas for more severe cases, the most important determinant was the loss in productivity. Newer, more affordable radiotherapy strategies may play a crucial role in the future treatment of early prostate cancer. The interpretation of our results depends on conducting thorough sensitivity analyses. This approach may help better understand parameter uncertainty and the methodological choices discussed in health economics studies. Future results of ongoing clinical trials that are considering genetic characteristics in assessing treatment response of patients with localized prostate cancer may shed new light on important clinical and pharmacoeconomic decisions.

Toxicity and outcomes after external beam irradiation for prostate cancer in patients with prior holmium laser enucleation of the prostate: Early experience

PURPOSE/OBJECTIVES

Holmium laser enucleation of the prostate (HoLEP) is commonly performed in patients with significant bladder outlet obstruction. However, there are few reports on the toxicity of external beam irradiation (RT) for prostate cancer in patients after prior HoLEP. In this study, we evaluate the side effects and treatment outcomes of RT after HoLEP.

MATERIALS/METHODS

Eighteen patients who had HoLEP and subsequently received RT for prostate cancer were included. Data collected included patient and disease characteristics, urinary function, and radiation dose. Acute and late urinary (GU) and gastrointestinal (GI) side effects were evaluated. Disease control and survival rates were calculated using Kaplan-Meier method.

RESULTS

Median follow-up was 18 months (range: 4-46 months). Median prostate volume was 107 ml before HoLEP and 24 ml after HoLEP. Median International Prostate Symptom Score (IPSS) was 17 (range: 5-32) before HoLEP. Median decline in IPSS score after HoLEP was 7 (range: -2-21). On uroflow study, peak flow rate, and post-void residual were significantly improved after HoLEP. After radiation, peak flow rate and average flow rate showed a decline but remained significantly improved compared to pre-HoLEP measurements. Maximum acute Common Terminology Criteria for Adverse Events (CTCAE) adverse events were 12 grade 1 and 3 grade 2 for GU, and 3 grade 1 for GI, respectively. Maximum late adverse events were 13 grade 1 and 2 grade 2 for GU, and all grade 0 for GI, respectively. At last follow-up, there were 8 grade 1 and 1 grade 2 late GU, and 3 grade 1 late GI adverse events, respectively. There was no significant increase in urinary incontinence after RT compared to before RT. The 18-month biochemical control, local control, distant control rates were 78%, 94%, and 80%, respectively.

CONCLUSIONS

Patients who received RT as definitive treatment for prostate cancer after prior HoLEP had low risk of serious acute and late side effects. HoLEP can be safely performed and should be considered in patients with significant bladder outlet obstruction and large prostate volume before RT.

Ex Vivo Fluorescence Confocal Microscopy (FCM) of Prostate Biopsies Rethought: Opportunities of Intraoperative Examinations of MRI-Guided Targeted Biopsies in Routine Diagnostics

Background: The diagnosis of prostate carcinoma (PCa) requires time- and material-consuming histopathological examinations. Ex vivo fluorescence confocal microscopy (FCM) can detect carcinoma foci in diagnostic biopsies intraoperatively. Methods: MRI-guided and systematic biopsies were identified in a dataset of our previously published study cohort. Detection rates of clinically relevant tumors were determined in both groups. A retrospective blinded trial was performed to determine how many tumors requiring intervention were detectable via FCM analysis of MRI-guided targeted biopsies alone. Results: MRI-guided targeted biopsies revealed tumors more frequently than systematic biopsies. Carcinomas in need of intervention were reliably represented in the MRI-guided biopsies and were identified in intraoperative FCM microscopy. Combined with serum PSA levels and clinical presentation, 91% of the carcinomas in need of intervention were identified. Conclusions: Intraoperative FCM analysis of MRI-guided biopsies is a promising approach for the efficient diagnosis of PCa. The method allows a timely assessment of whether a tumor disease requiring intervention is present and can reduce the psychological stress of the patient in the waiting period of the histological finding. Furthermore, this technique can lead to reduction of the total number of biopsies needed for the diagnosis of PCa.

No significant difference in intermediate key outcomes in men with low- and intermediate-risk prostate cancer managed by active surveillance

Active surveillance (AS) is standard of care for patients with low-risk prostate cancer (PCa), but its feasibility in intermediate-risk patients is controversial. We compared outcomes of low- and intermediate-risk patients managed with multiparametric magnetic resonance imaging (mpMRI)-supported AS in a community hospital. Of the 433 patients enrolled in AS between 2009 and 2016, 358 complied with AS inclusion criteria (Cancer of the Prostate Risk Assessment (CAPRA) score ≤ 5, Gleason grade group (GGG) ≤ 2, clinical stage ≤ cT2 and prostate-specific antigen (PSA) ≤ 20 ng/ml) and discontinuation criteria (histological-, PSA-, clinical- or radiological disease reclassification). Of the 358 patients, 177 (49%) were low-risk and 181 (51%) were intermediate-risk. Median follow-up was 4.2 years. The estimated 5-year treatment-free survival (TFS) was 56% (95% confidence interval [CI] 51-62%). Intermediate-risk patients had significantly shorter TFS compared with low-risk patients (hazard ratio 2.01, 95% CI 1.47-2.76, p < 0.001). There were no statistically significant differences in the rate of adverse pathology, biochemical recurrence-free survival and overall survival between low- and intermediate-risk patients. Two patients developed metastatic disease and three died of PCa. These results suggest that selected patients with intermediate-risk PCa may be safely managed by mpMRI-supported AS, but longer follow-up is necessary.