Management of patients with an increasing prostate-specific antigen after radical prostatectomy

ACR Appropriateness Criteria® Post-Treatment Follow-up of Prostate Cancer: 2022 Update

Prostate cancer has a wide spectrum ranging between low-grade localized disease and castrate-resistant metastatic disease. Although whole gland and systematic therapies result in cure in the majority of patients, recurrent and metastatic prostate cancer can still occur. Imaging approaches including anatomic, functional, and molecular modalities are continuously expanding. Currently, recurrent and metastatic prostate cancer is grouped in three major categories: 1) Clinical concern for residual or recurrent disease after radical prostatectomy, 2) Clinical concern for residual or recurrent disease after nonsurgical local and pelvic treatments, and 3) Metastatic prostate cancer treated by systemic therapy (androgen deprivation therapy, chemotherapy, immunotherapy). This document is a review of the current literature regarding imaging in these settings and the resulting recommendations for imaging. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Detecting recurrent prostate Cancer using multiparametric MRI, influence of PSA and Gleason grade

BACKGROUND

The utility of multiparametric MRI (mpMRI) in detecting suspected local recurrence post radical prostatectomy (RP) may be associated with PSA and Gleason grade. The purpose of the study was to evaluate the likelihood of detecting locally recurrent prostate cancer utilizing mpMRI in patients with suspected recurrence following radical prostatectomy (RP) parsed by PSA and Gleason grade.

METHODS

One hundred ninety five patients with suspected local recurrence were imaged on a 1.5 T MRI with torso array and endorectal coil in this retrospective study. mpMRI interpretations were stratified by PSA and lower (Gleason < 7) vs. higher grade tumors (Gleason 8-10). Recursive partitioning was used to determine whether mpMRI interpretations could be classified as positive or negative.

RESULTS

The majority of mpMRI interpretations in patients with lower Gleason grade tumors and PSA < 0.5 ng/mL were negative (68/78, 87.2%, p = 0.004). The majority of mpMRI interpretations in patients with higher Gleason grade tumors and PSA > 1.5 ng/mL were positive (8/9, 88.9%, p = 0.003). Findings were corroborated by recursive partitioning, which identified a PSA = 0.5 ng/ml in patients with lower grade tumors and a PSA = 1.5 ng/mL in patients with higher grade tumors as differentiating negative and positive mpMRIs.

CONCLUSION

In the setting of suspected recurrence after RP, mpMRI results are associated with PSA and Gleason grade, both of which can help guide when mpMRI may find utility. mpMRI is likely to be low diagnostic yield and negative for recurrence (87%) in the setting of lower Gleason grade tumors and PSA < 0.5 ng/mL. mpMRI is likely to be of low diagnostic value and positive for recurrence (89%) in the setting of PSA > 1.5 ng/mL and higher grade tumors; in this case, mpMRI findings may be more useful for directing biopsy and local therapy. Between these extremes, PSA > 0.5 ng/mL and lower grade tumors or PSA < 1.5 ng/mL and higher grade tumors, mpMRI results are less predictable, suggesting greater diagnostic value for detecting recurrence post prostatectomy.

Post-treatment prostate MRI

Accurate early detection of recurrent prostate cancer after surgical or nonsurgical treatment is increasingly relevant in the era of evolving options for salvage therapy. The importance of differentiating between local tumor recurrence, distant metastatic disease, and a combination of both in a patient with biochemical recurrence of prostate cancer is essential for appropriate treatment selection. Magnetic resonance imaging (MRI) is the best test for localization and characterization of locally residual or recurrent prostate cancer. It is essential for the radiologist involved in prostate MRI interpretation to be familiar with key imaging findings and advantages of different sequences to reach a confident diagnosis in the post-treatment setting. In this pictorial review, we present imaging findings of post-treatment prostate MRI including expected post-treatment anatomy and imaging characteristics, and the typical appearances of local tumor recurrence after radical prostatectomy, radiation therapy, and focal therapy for prostate cancer. While a multi-parametric MRI approach remains key just as in the treatment-naïve gland, this review emphasizes the much greater importance of the dynamic contrast-enhanced MRI sequence for evaluation in the post-treatment setting.

Imaging Biochemical Recurrence After Prostatectomy: Where Are We Headed?

OBJECTIVE. In this article, we discuss the evolving roles of imaging modalities in patients presenting with biochemical recurrence after prostatectomy. CONCLUSION. Multiple imaging modalities are currently available to evaluate patients with prostate cancer presenting with biochemical recurrence after prostatectomy. Multiparametric MRI (mpMRI) focuses on the postsurgical bed as well as regional lymph nodes and bones. PET/CT studies using ¹⁸F-fluciclovine, ¹¹C-choline, and prostate-specific membrane antigen (PSMA) ligands are useful in detecting locoregional and distant metastasis. Multiparametric MRI is preferred for patients with low risk of metastasis for localizing recurrence in prostate bed as well as pelvic lymph node and bone recurrence. Moreover, mpMRI aids in guiding biopsy and additional salvage treatments. For patients with high risk of metastatic disease, both mpMRI and whole-body PET/CT may be performed. PET/MRI using ⁶⁸Ga-PSMA has potential to enable a one-stop shop for local recurrence and metastatic disease evaluation, and clinical trials of PET/MRI are ongoing.

Convex-Optimization-Based Compartmental Pharmacokinetic Analysis for Prostate Tumor Characterization Using DCE-MRI

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a powerful imaging modality to study the pharmacokinetics in a suspected cancer/tumor tissue. The pharmacokinetic (PK) analysis of prostate cancer includes the estimation of time activity curves (TACs), and thereby, the corresponding kinetic parameters (KPs), and plays a pivotal role in diagnosis and prognosis of prostate cancer. In this paper, we endeavor to develop a blind source separation algorithm, namely convex-optimization-based KPs estimation (COKE) algorithm for PK analysis based on compartmental modeling of DCE-MRI data, for effective prostate tumor detection and its quantification. The COKE algorithm first identifies the best three representative pixels in the DCE-MRI data, corresponding to the plasma, fast-flow, and slow-flow TACs, respectively. The estimation accuracy of the flux rate constants (FRCs) of the fast-flow and slow-flow TACs directly affects the estimation accuracy of the KPs that provide the cancer and normal tissue distribution maps in the prostate region. The COKE algorithm wisely exploits the matrix structure (Toeplitz, lower triangular, and exponential decay) of the original nonconvex FRCs estimation problem, and reformulates it into two convex optimization problems that can reliably estimate the FRCs. After estimation of the FRCs, the KPs can be effectively estimated by solving a pixel-wise constrained curve-fitting (convex) problem. Simulation results demonstrate the efficacy of the proposed COKE algorithm. The COKE algorithm is also evaluated with DCE-MRI data of four different patients with prostate cancer and the obtained results are consistent with clinical observations.

[Time-influencing factors for biochemical progression following radical prostatectomy]

INTRODUCTION

We assessed the time-influencing clinical-pathological factors for biochemical progression of an equal series of patients from a single institution.

MATERIALS AND METHODS

Retrospective analysis of 278 patients with biochemical progression following prostatectomy. We considered biochemical progression to be PSA>0.4 ng/ml. We performed the trial using the Cox model (univariate and multivariate) and using the Student's t-test to compare averages.

RESULTS

With a mean follow-up of 4 (±3 DE) years, the univariate study showed a mean until progression for the Gleason score 2-6 in the biopsy of 824 days and 543 for the Gleason score 7-10 (p=0.003). For negative surgical margins, the mean was 920 days and 545 for positive margins (p=0.0001). In the case of a Gleason score 2-7 in the specimen, the mean was 806 days and 501 for a Gleason score 8-10 (p=0.001). Lastly, the mean for the cases with Ki-67 negative in the specimen (< 10%) was 649 days and 345 for Ki-67 positive (> 10%) (p=0.003). In the multivariate study, Ki-67 (OR 1.028; IC 95% 1-1.01; p=0.0001) and Gleason score 8-10 (OR 1.62; IC 95% 1.5-2.45; p=0.026) in the specimen, and initial PSA >10 ng/ml (OR 1.02; IC 95% 1.01-1.04; p=0.0001) were independent variables. Using these variables, we designed a predictive model with three groups. The time until the progression of each group was 1,081, 551 and 218 days respectively.

CONCLUSION

The Gleason score 7-10 in the prostate biopsy, the presence of Ki-67, the positive margins and the Gleason score 8-10 in the specimen, and the initial PSA > 10 ng/ml are time-influencing factors until biochemical progression. Pathological Gleason score 8-10, PSA > 10 ng/ml and Ki-67 are independent factors.

Diagnostic evaluation of PSA recurrence and review of hormonal management after radical prostatectomy

The aim of this review is to provide a discussion of the diagnostic evaluation of biochemical recurrence following radical prostatectomy (RP) and an overview of the postoperative hormonal treatment (HT) options. As no randomized trials in the clinical setting of postoperative prostate-specific antigen recurrence have been reported, there is no conclusive evidence that HT after RP will prolong survival or reduce morbidity. Non-traditional approaches, such as intermittent androgen deprivation, non-steroidal anti-androgens and combination of finasteride and non-steroidal anti-androgen, are investigated and may be acceptable options. Combinations of HT with radiotherapy and/or chemotherapy for treatment of recurrent prostate cancer are under study.

A variant TMPRSS2 isoform and ERG fusion product in prostate cancer with implications for molecular diagnosis

Prostate cancer is the most commonly diagnosed cancer among men in the United States. Recently, fusion of TMPRSS2 with ETS family oncogenic transcription factors has been identified as a common molecular alteration in prostate cancer, where most often the rearrangement places ERG under the androgen-regulated transcriptional control of TMPRSS2. Here, we carried out rapid amplification of cDNA ends (RACE) on a prostate cancer specimen carrying an atypical aberration discovered by array-based comparative genomic hybridization (array CGH), suggesting an alternative fusion partner of ERG. We identified novel transcribed sequences fused to ERG, mapping 4 kb upstream of the TMPRSS2 start site. The sequences derive from an apparent second TMPRSS2 isoform, which we found also expressed in some prostate tumors, suggesting similar androgen-regulated control. In a reverse transcription-polymerase chain reaction (RT-PCR)-based survey of 63 prostate tumor specimens (54 primary and nine lymph node metastases), 44 (70%) cases expressed either the known or novel variant TMPRSS2-ERG fusion, 28 (44%) expressed both, 10 (16%) expressed only the known, and notably six (10%) expressed only the variant isoform fusion. In this specimen set, the presence of a TMPRSS2-ERG fusion showed no statistical association with tumor stage, Gleason grade or recurrence-free survival. Nonetheless, the discovery of a novel variant TMPRSS2 isoform-ERG fusion adds to the characterization of ETS-family rearrangements in prostate cancer, and has important implications for the accurate molecular diagnosis of TMPRSS2-ETS fusions.

Prognostic value of PINP, bone alkaline phosphatase, CTX-I, and YKL-40 in patients with metastatic prostate carcinoma

BACKGROUND

To examine the prognostic value of markers of bone metabolism (serum PINP, BAP, and CTX-I) and serum YKL-40 in metastatic prostate carcinoma (PC).

METHODS

The biomarkers were determined by ELISAs in 153 metastatic PC patients before treatment with parenteral estrogen or total androgen ablation. The median follow-up was 4.9 years. One hundred fifteen patients died.

RESULTS

The biomarkers were increased in the patients compared to controls (P < 0.001), and related to performance status and Soloway score (except YKL-40), but not to T-category and WHO tumor grade. PINP was elevated in 87%, BAP (55%), CTX-I (33%), and YKL-40 (43%). Univariate analysis showed an association to survival: PINP (HR = 1.6, P < 0.0001), BAP (HR = 1.4, P < 0.0001), CTX-I (HR = 1.7, P < 0.0001), and YKL-40 (HR = 1.4, P = 0.004). In multivariate Cox analysis performance status, WHO grade, Soloway score, PINP, and YKL-40 were independently predictive factors.

CONCLUSIONS

High serum PINP, BAP, CTX-I, and YKL-40 are associated with poor outcome of metastatic PC patients.

The retinoic acid synthesis gene ALDH1a2 is a candidate tumor suppressor in prostate cancer

Prostate cancer is the most common cancer among men in the United States, and aberrant DNA methylation is known to be an early molecular event in its development. Here, we have used expression profiling to identify novel hypermethylated genes whose expression is induced by treatment of prostate cancer cell lines with the DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine (5-aza-dC). Of the 271 genes that were induced by 5-aza-dC treatment, 25 also displayed reduced expression in primary prostate tumors compared with normal prostate tissue, and the decreased expression of only one gene, aldehyde dehydrogenase 1 family, member A2 (ALDH1a2), was also associated with shorter recurrence-free survival. ALDH1a2 encodes an enzyme responsible for synthesis of retinoic acid (RA), a compound with prodifferentiation properties. By immunohistochemistry, we observed that ALDH1a2 was expressed in epithelia from normal prostate but not prostate cancer. Using bisulfite sequencing, we determined that the ALDH1a2 promoter region was significantly hypermethylated in primary prostate tumors compared with normal prostate specimens (P = 0.01). Finally, transfection-mediated reexpression of wild-type ALDH1a2 (but not a presumptive catalytically dead mutant) in the prostate cancer cell line DU145 resulted in decreased colony growth (P < 0.0001), comparable with treatment with either 5-aza-dC or RA. Taken together, our findings implicate ALDH1a2 as a candidate tumor suppressor gene in prostate cancer and further support a role of retinoids in the prevention or treatment of prostate cancer.