Undergrading and understaging in patients with clinically insignificant prostate cancer who underwent radical prostatectomy

Indoleamine 2,3-dioxygenase expression in the prognosis of the localized prostate cancer

BACKGROUND

Indoleamine 2,3-dioxygenase (IDO1) is an enzyme that acts as an immunomodulatory molecule. It is found in several types of cancer where it seems to be associated with tumor escape due to its immunosuppressive mechanisms. However, the role of IDO1 expression in prostate cancer (PC) is unclear. The aim of our study was to evaluate the expression of IDO1 in localized PC and to correlate with the classic prognostic factor and recurrence after surgical treatment.

METHODS

We retrospectively evaluated surgical specimens from 111 patients with localized PC, who underwent radical prostatectomy. Recurrence was defined as a prostate specific antigen (PSA) level exceeding 0.2 ng/mL postoperatively, and the follow-up was 123 months. IDO1 expression was evaluated by immunohistochemistry in 72 cases of which 42 (58%) had biochemical recurrence.

RESULTS

Lower IDO1 expression was associated with higher Gleason score (p = 0.022) and PSA levels (p = 0.042). The multivariate analyses revealed that the loss of IDO1 and higher PSA were independently associated with biochemical recurrence. The chance of recurrence was increased by 85% in patients with lower IDO1 [OR = 0.15; p = 0.009 CI 95% (0.038-0.633)] and increased by 5.5 times in patients with higher PSA [OR = 5.51; p = 0.012 CI 95% (1.435-21.21)]. The recurrence-free survival curve also demonstrates that lower IDO1 was associated with lower time to biochemical recurrence (p = 0.0004).

CONCLUSION

The loss of IDO1 expression was associated with increased chance of biochemical recurrence, higher PSA, and a Gleason score in localized PC.

Diagnostic performance of 68Gallium-PSMA-11 PET/CT to detect significant prostate cancer and comparison with 18FEC PET/CT

Background

Radiolabeled prostate-specific membrane antigen (PSMA) has proven to be a highly accurate method to detect recurrence and metastases of prostate cancer, but only sparse data is available about its performance in the diagnosis of clinically significant primary prostate cancer.

Methods

We compared ⁶⁸Ga-PSMA-11 PET/CT in 25 patients with ¹⁸FEC PET/CT in 40 patients with suspected prostate carcinoma based on an increased PSA level.The PET/CT results were compared with the histopathologic Gleason Score (GS) of biopsies.

Results

The ⁶⁸Ga-PSMA-11 PET/CT revealed highly suspect prostatic lesions (maximum standardized uptake value/SUV_max >2.5) in 21/25 patients (84%), associated with GS≥6 (low-grade/high-grade carcinoma). Two histopathologic non-malignancy-relevant cases (GS<6) had PSMA-SUV_max ≤2.5; all histopathologic high-grade cases (GS≥7b) showed PSMA-SUV_max >12.0 which further increased with rising GS. There were 2 false positives and no false negative findings for high-grade prostate cancer using a cut off-level for SUV_max of 2.5.In contrast, the ¹⁸FEC PET/CT showed suspected malignant lesions in 38/40 patients (95%), which included 3 lesions with GS<6. The mean SUV_max values did not differ with different GS. There were 11 false positives and 1 false negative for detection of high-grade prostate cancer (cut off 2.5).By means of ROC analysis a SUV_max of 5.4 was found to be an optimal cut off-level to distinguish between low- and high-grade carcinoma in ⁶⁸Ga-PSMA-11 PET/CT (AUC=0.9692; 95% CI 0.9086;1.0000;SD(AUC)=0.0309)). Choosing a cut off-level of SUV_max5.4, ⁶⁸Ga-PSMA-11 PET/CT was able to distinguish between GS ≤7a/≥7b with a sensitivity of 84%, a specificity of 100%, a negative predictive value (NPV) of 67%, and an efficiency of 88% (p<0.001).The ROC analysis revealed a SUV_max 6.5 as an optimal cut off-level to distinguish between low- and high-grade carcinoma in ¹⁸FEC PET/CT (AUC=0.7470; 95% CI 0.5919;0.9020;SD(AUC)=0.0791) with a sensitivity of 61% and a specificity of 92%; but the efficiency was only 70% and the NPV 50% (p=0.01).

Conclusion

⁶⁸Ga-PSMA-11 PET/CT guided biopsy of the prostate increases diagnostic precision and is likely to help to reduce overtreatment of low-grade malignant disease as well as detect the foci of the highest Gleason pattern. Both methods (⁶⁸Ga-PSMA-11,¹⁸FEC) were suitable to detect primary prostate cancer, but the excellent image quality, the higher specificity and the good correlation of positive scans with GS are advantages of ⁶⁸Ga-PSMA-11.

[Diagnostic significance of multiparametric MRI combined with US-fusion guided biopsy of the prostate in patients with increased PSA levels and negative standard biopsy results to detect significant prostate cancer - Correlation with the Gleason score. Korrelation mit dem Gleason Score]

AIMS

To increase diagnostic precision and to reduce overtreatment of low-risk malignant disease, multiparametric MRI (mpMRI) combined with ultrasound (US) fusion guided biopsy of the prostate were performed.

METHODS

In 99 male patients with increased PSA plasma levels and previous negative standard biopsy procedures, mpMRI was carried out followed by US fusion guided perineal biopsy. PI-RADS-Data (PS) of mpMRI and histopathological Gleason score (GS) were categorized and statistically compared.

RESULTS

Lesions in 72/99 (73 %) of patients were determined to be suspect of malignancy, based on a PS 4 or 5. In 33/99 (33 %) of patients, malignancy could not be confirmed by histopathology. With regard to the remaining 66 patients with previous negative biopsy results, 42 (64 %) were diagnosed with a low-grade carcinoma (GS 6, 7a) and 24 (36 %) with a high-grade carcinoma (GS ≥ 7b). The proportion of corresponding results in mpMRI (PS 4-5) when a high-grade carcinoma had been detected, was 21/24 (88 %), which related to a sensitivity of 88 % and a negative predictive value (NPV) of 85 % (p = 0,002). In addition, 35 of 42 patients (83%), graded PS 4-5 in mpMRI, were diagnosed with low-grade carcinoma-positive (p < 0,001). Sensitivity to differentiation between low- and high-grade carcinomas (GS ≤ 7a vs. ≥ 7b) by means of PS was 88 % with a NPV of 70 % (p = 0,74).

CONCLUSION

Our results suggest that mpMRI combined with US-fusion guided biopsy is able to detect considerably higher rates of clinically relevant prostate malignancies compared to conventional diagnostic procedures. However, no statistical significance could be shown regarding the differentiation between high- and low-grade carcinomas. It is hoped that the hybrid methods PSMA-PET/CT or PSMA-PET/MRI will lead to the next optimization step in the differentiation between high- and low-grade carcinomas which so far has been unsatisfactory.

A Cost-Utility Analysis of Prostate Cancer Screening in Australia

BACKGROUND AND OBJECTIVES

The Göteborg randomised population-based prostate cancer screening trial demonstrated that prostate-specific antigen (PSA)-based screening reduces prostate cancer deaths compared with an age-matched control group. Utilising the prostate cancer detection rates from this study, we investigated the clinical and cost effectiveness of a similar PSA-based screening strategy for an Australian population of men aged 50-69 years.

METHODS

A decision model that incorporated Markov processes was developed from a health system perspective. The base-case scenario compared a population-based screening programme with current opportunistic screening practices. Costs, utility values, treatment patterns and background mortality rates were derived from Australian data. All costs were adjusted to reflect July 2015 Australian dollars (A$). An alternative scenario compared systematic with opportunistic screening but with optimisation of active surveillance (AS) uptake in both groups. A discount rate of 5 % for costs and benefits was utilised. Univariate and probabilistic sensitivity analyses were performed to assess the effect of variable uncertainty on model outcomes.

RESULTS

Our model very closely replicated the number of deaths from both prostate cancer and background mortality in the Göteborg study. The incremental cost per quality-adjusted life-year (QALY) for PSA screening was A$147,528. However, for years of life gained (LYGs), PSA-based screening (A$45,890/LYG) appeared more favourable. Our alternative scenario with optimised AS improved cost utility to A$45,881/QALY, with screening becoming cost effective at a 92 % AS uptake rate. Both modelled scenarios were most sensitive to the utility of patients before and after intervention, and the discount rate used.

CONCLUSION

PSA-based screening is not cost effective compared with Australia's assumed willingness-to-pay threshold of A$50,000/QALY. It appears more cost effective if LYGs are used as the relevant outcome, and is more cost effective than the established Australian breast cancer screening programme on this basis. Optimised utilisation of AS increases the cost effectiveness of prostate cancer screening dramatically.

High risk of under-grading and -staging in prostate cancer patients eligible for active surveillance

Background

Active surveillance (AS) is increasingly offered to patients with low risk prostate cancer. The present study was conducted to evaluate the risk of tumor under-grading and -staging for AS eligibility. Moreover, we analyzed possible biomarkers for predicting more unfavorable final tumor histology.

Methods

197 patients who underwent radical prostatectomy (RPE) but would have met the EAU (European Association of Urology) criteria for AS (PSA<10 ng/ml, biopsy GS ≤6, ≤2 cancer-positive biopsy cores with ≤50% of tumor in any core and clinical stage ≤T2a) were included in the study. These AS inclusion parameters were correlated to the final histology of the RPE specimens. The impact of preoperative PSA level (low PSA ≤4 ng/ml vs. intermediate PSA of >4–10 ng/ml), PSA density (<15 vs. ≥ 15 ng/ml) and the number of positive biopsy cores (1 vs. 2 positive cores) on predicting upgrading and final adverse histology of the RPE specimens was analyzed in uni- and multivariate analyses. Moreover, clinical courses of undergraded patients were assessed.

Results

In our patient cohort 41.1% were found under-graded in the biopsy (final histology 40.1% GS7, 1% GS8). Preoperative PSA levels, PSA density or the number of positive cores were not predictive for worse final pathological findings including GS >6, extraprostatic extension and positive resection margin (R1) or correlated significantly with up-grading and/or extraprostatic extension in a multivariate model. Only R1 resections were predictable by combining intermediate PSA levels with two positive biopsy cores (p = 0.004). Sub-analyses showed that the number of biopsy cores (10 vs. 15 biopsy cores) had no influence on above mentioned results on predicting biopsy undergrading. Clinical courses of patients showed that 19.9% of patients had a biochemical relapse after RPE, among all of them were undergraded in the initial biopsy.

Conclusion

In summary, this study shows that a multitude of patients fulfilling the criteria for AS are under-diagnosed. The use of preoperative PSA levels, PSA density and the number of positive cores were not predictable for undergrading in the present patient collective.

The cost-utility of open prostatectomy compared with active surveillance in early localised prostate cancer

BACKGROUND

There is an on-going debate about whether to perform surgery on early stage localised prostate cancer and risk the common long term side effects such as urinary incontinence and erectile dysfunction. Alternatively these patients could be closely monitored and treated only in case of disease progression (active surveillance). The aim of this paper is to develop a decision-analytic model comparing the cost-utility of active surveillance (AS) and radical prostatectomy (PE) for a cohort of 65 year old men with newly diagnosed low risk prostate cancer.

METHODS

A Markov model comparing PE and AS over a lifetime horizon was programmed in TreeAge from a German societal perspective. Comparative disease specific mortality was obtained from the Scandinavian Prostate Cancer Group trial. Direct costs were identified via national treatment guidelines and expert interviews covering in-patient, out-patient, medication, aids and remedies as well as out of pocket payments. Utility values were used as factor weights for age specific quality of life values of the German population. Uncertainty was assessed deterministically and probabilistically.

RESULTS

With quality adjustment, AS was the dominant strategy compared with initial treatment. In the base case, it was associated with an additional 0.04 quality adjusted life years (7.60 QALYs vs. 7.56 QALYs) and a cost reduction of €6,883 per patient (2011 prices). Considering only life-years gained, PE was more effective with an incremental cost-effectiveness ratio of €96,420/life year gained. Sensitivity analysis showed that the probability of developing metastases under AS and utility weights under AS are a major sources of uncertainty. A Monte Carlo simulation revealed that AS was more likely to be cost-effective even under very high willingness to pay thresholds.

CONCLUSION

AS is likely to be a cost-saving treatment strategy for some patients with early stage localised prostate cancer. However, cost-effectiveness is dependent on patients' valuation of health states. Better predictability of tumour progression and modified reimbursement practice would support widespread use of AS in the context of the German health care system. More research is necessary in order to reliably quantify the health benefits compared with initial treatment and account for patient preferences.

Laparoscopic radical prostatectomy plus extended lymph nodes dissection for cases with non-extra node metastatic prostate cancer: 5-year experience in a single Chinese institution

OBJECTIVE

To investigate the functional and oncologic outcomes of patients with locally advanced or lymph node metastatic prostate cancer (PCa) treated by laparoscopic radical prostatectomy (LRP) in a single Chinese institution.

METHODS

From June 2004 to June 2011, a total of 152 cases including 105 locally advanced PCa and 47 lymph node metastatic PCa who were treated by LRP with extended lymph node dissection (ePLND) were enrolled in this study. Surgical records, urinary continence, complications, and oncologic outcomes were presented.

RESULTS

The mean operation time and bleeding were 240 min and 110 ml, respectively. After 12-87 months (median 48 m) of follow-up, 91.4 and 94.7 % of the patients were urinary continence at 6 and 12 m, respectively. Eighty biochemical recurrent diseases were observed. The 3- and 5-year biochemical progression-free survival rates were 59.2 and 47.3 %, respectively. Multivariate analysis showed that Gleason score (HR: 1.66, 95 % CI: 1.05-2.64, P = 0.031), pathological stage (HR: 1.64, 95 % CI: 1.2-2.23, P = 0.002), and surgical margin status (HR: 1.75, 95 % CI: 1.04-2.95, P = 0.035) were independent predictive factors for subsequent biochemical relapse. The 3- and 5-year overall and cancer-specific survival rates were 90.2, 86.0 and 95.8, 92.3 %, respectively. There were no significant differences in biochemical recurrence-free (42.6 vs. 49.5 %, P = 0.491), overall (83.4 vs. 87.3 % P = 0.503), and cancer-specific survival rates (92.3 vs. 94.9 %, P = 0.801) between lymph node-positive and -negative PCa.

CONCLUSION

With favorable functional and oncologic outcomes in this cohort of 152 patients, we concluded that LRP plus ePLND is feasible for patients with locally advanced non-extra node metastatic PCa.

Risk of Gleason grade inaccuracies in prostate cancer patients eligible for active surveillance

OBJECTIVE

To evaluate increases in Gleason grade because of sample bias after immediate rebiopsy or prostatectomy for patients considered active surveillance candidates by institutional protocol.

METHODS

A contemporary medical literature search was performed using PubMed. Series were included if the patients had no more than Gleason 6 prostate cancer score on initial biopsy and underwent a prostatectomy or rebiopsy within 6 months. Patient sets using neoadjuvant hormonal therapy or focal prostate treatment were excluded.

RESULTS

In patients who would have fallen into the D'Amico low-risk prostate cancer group, 42% were found to have an increase in the Gleason score: 32% resulting in grade ≥ 7 disease and 3% grade ≥ 8. For series that limited patients to the Epstein criteria, Gleason upgrades were 34%, 29%, and 2%, respectively. Of the 139 patients whose second tissue specimens were from a rebiopsy, 17% were found to have grade ≥ 7 disease, whereas only 1 patient had grade ≥ 8. There were no consistent multivariate analysis variables among the series to predict for an increase in Gleason score.

CONCLUSION

More than one third of the patients were found to have been undergraded based on their initial prostate biopsy. Therefore, 1 biopsy alone may not be sufficient to offer active surveillance as an option. Further exploration is necessary to better ensure low-risk disease before active surveillance.

Active surveillance for favorable-risk prostate cancer: background, patient selection, triggers for intervention, and outcomes

With the advent of increasingly sensitive and widely used diagnostic testing, cancer overdiagnosis in particular has emerged as a problem in multiple organ sites. This has the greatest ramifications in the case of prostate cancer because of the very high incidence of latent prostate cancer in aging men, the availability of the prostate-specific antigen (PSA) test, and the long-term effects of definitive therapy. The condition of most men with favorable-risk prostate cancer is far removed from the consequences of a rampaging, aggressive disease. Most of these men are not destined to die of their disease, even in the absence of treatment. Unfortunately, most of these patients are treated radically and are exposed to the risk of significant side effects. Therefore, a selective approach to treatment is appealing. The concept is to identify the subset that harbor more aggressive disease early enough that curative therapy is still a possibility, thereby allowing the others to enjoy improved quality of life, free from the side effects of treatment. This review article summarizes the evidence supporting active surveillance, and the current approach to this management strategy, including the roles of serial biopsy, PSA kinetics, and MR imaging.

Pathological outcomes of men eligible for active surveillance after undergoing radical prostatectomy: are results predictable?

INTRODUCTION

To analyze pathological results in patients with prostate cancer eligible for active surveillance (AS) after radical prostatectomy and available prediction systems.

METHODS

A retrospective analysis was performed of 612 patients who underwent radical prostatectomy during a 14-year period. Subsequently, we selected those patients who would have been eligible for AS according to 2 different published criteria. Group AS-A matched the following criteria: ≤T2a; Gleason Score ≤6; and prostate-specific antigen <10 ng/mL, while group AS-B applied to different criteria: ≤T2a; Gleason Score <7; and prostate-specific antigen ≤15 ng/mL. Pathological outcomes were compared with results of the 2001 Partin tables.

RESULTS

Altogether, 125 (20.4%) patients were included in group AS-A and 159 (25.9%) in group AS-B. We detected 32 cases of >pT2c (25.6%) for group AS-A and 47 cases (29.6%) for AS-B, respectively. Gleason score upgrading was recorded in 34.4% (AS-A) and 38.3% (AS-B). Results of the Partin tables showed good discrimination among patients at risk for positive lymph nodes but limited discrimination for organ-confined disease, seminal vesicle.

CONCLUSIONS

Overall >25% of patients eligible for AS showed either upstaging or Gleason score upgrading, which could not be measured with the examined predictive tools. Patients should be informed about the risks of inaccurate preoperative diagnostic.

Undergrading and understaging in patients with clinically insignificant prostate cancer who underwent radical prostatectomy

PURPOSE

The aim of our study is to evaluate the undergrading and understaging rates in patients with clinically localized insignificant prostate cancer who underwent radical prostatectomy.

MATERIALS AND METHODS

Between July 2005 and July 2008, 406 patients underwent radical prostatectomy for clinical localized prostate cancer in our hospital. Based on preoperative data, 93 of these patients fulfilled our criteria of non-significance: Gleason score < 7, stage T1c, PSA < 10 ng/mL and percentage of affected fragments less than 25%. The pathologic stage and Gleason score were compared to preoperative data to evaluate the rate of understaging and undergrading. The biochemical recurrence free survival of these operated insignificant cancers were also evaluated.

RESULTS

On surgical specimen analysis 74.7% of patients had Gleason score of 6 or less and 25.3% had Gleason 7 or greater. Furthermore 8.3% of cases showed extracapsular extension. After 36 months of follow-up 3.4% had biochemical recurrence, defined by a PSA above 0.4 ng/mL.

CONCLUSIONS

Despite the limited number of cases, we have found considerable rates of undergrading and understaging in patients with prostate cancer whose current definitions classified them as candidates for active surveillance. According to our results the current definition seems inadequate as up to a third of patients had higher grade or cancer outside the prostate.