Progression of prostate cancer despite an extremely low serum level of prostate-specific antigen

Case report: Robotically visualized and biopsy-confirmed peritoneal carcinomatosis as initial identification of metastatic prostate adenocarcinoma in a patient with a history of prostatic urethral lift

Background

Peritoneal carcinomatosis is a particularly rare presentation of prostate cancer. Here we report a rare clinical case of surgically identified peritoneal carcinomatosis at the time of a planned robotic prostatectomy in a patient with a history of prostatic urethral lift procedure.

Case presentation

A 72-year-old man, with a history of urinary retention managed with tamsulosin, presented to his local urologist. Prostatic urethral lift procedures were performed for symptom management. After a definitive uptrend in his prostate-specific antigen (PSA) values, a biopsy was obtained, which demonstrated prostate adenocarcinoma. On presurgical multidisciplinary review, it was presumed that he had very high-risk localized prostate cancer. However, upon initiation of robotically assisted laparoscopic radical prostatectomy (RALP), he was noted to have numerous punctate white plaques on the peritoneum; biopsy of these lesions confirmed metastatic disease-for which the patient was starting on triple therapy per the PEACE-1 trial. The PSA level responded appropriately, decreasing from 16.8 to 0.08. Genetic testing was performed and returned negative for any clinically significant mutations.

Conclusion

Our patient, diagnosed with peritoneal carcinomatosis during a planned RALP, highlights the importance of vigilant laparoscopic exam prior to this prostatectomy. Multidisciplinary discussion is crucial for individualized and optimal treatment planning.

Patient outcomes following a response biomarker-guided approach to treatment using 177Lu-PSMA-I&T in men with metastatic castrate-resistant prostate cancer (Re-SPECT)

Background

¹⁷⁷LuPSMA is an effective treatment in metastatic castrate-resistant prostate cancer with trials adopting a standardised dose interval. Adjusting treatment intervals utilising early response biomarkers may improve patient outcomes.

Objective

This study evaluated progression-free survival (PFS) and overall survival (OS) based on treatment interval adjustment utilising ¹⁷⁷LuPSMA 24-h SPECT/CT (¹⁷⁷Lu-SPECT) and early prostate-specific antigen (PSA) response.

Design

Retrospective analysis of a clinical ¹⁷⁷Lu-PSMA-I&T treatment programme.

Methods

In all, 125 men were treated with 6-weekly ¹⁷⁷LuPSMA-I&T [median 3 cycles, interquartile range (IQR): 2-4], median dose 8.0 GBq [95% confidence interval (CI): 7.5-8.0]. Imaging screening involved ⁶⁸GaPSMA-11 PET/diagnostic CT. ¹⁷⁷Lu-SPECT/diagnostic CT was acquired following each therapy, and clinical assessments 3-weekly. Following dose 2 (week 6), a composite PSA and ¹⁷⁷Lu-SPECT/CT imaging response [partial response (PR), stable disease (SD), and progressive disease (PD)] determined ongoing management. Response group (RG) 1 (marked reduction in PSA/imaging PR) break in treatment until subsequent PSA rise, then re-treatment. RG 2 (stable or reduced PSA and/or imaging SD) 6-weekly treatments until six doses, or no longer clinically benefitting. RG 3 (rise in PSA and/or imaging PD) recommended for an alternative treatment.

Results

Overall PSA50% response rate (PSARR) was 60% (75/125), median PSA-PFS 6.1 months (95%CI: 5.5-6.7), and median OS 16.8 months (95%CI: 13.5-20.1). 35% (41/116) were classified as RG 1, 34% (39/116) RG 2, and 31% (36/116) RG 3. PSARRs by RG were 95% (38/41), 74% (29/39), and 8% (3/36); median PSA-PFS rates were 12.1 months (95%CI: 9.3-17.4), 6.1 months (95%CI: 5.8-9.0), and 2.6 months (95%CI: 1.6-3.1); and OS rates were 19.2 months (95%CI: 16.8-20.7), 13.2 months (95%CI: 12.0-18.8), and 11.2 months (95%CI: 8.7-15.6) for RG 1, 2, and 3, respectively. The median months of 'treatment holiday' for RG 1 was 6.1 months (IQR: 3.4-8.7). Nine men had received prior ¹⁷⁷LuPSMA-617 and were retreated with ¹⁷⁷LuPSMA-I&T, with a PSARR of 56% on re-treatment.

Conclusion

Personalising dosing regimens using early response biomarkers with ¹⁷⁷LuPSMA has the potential to achieve similar treatment responses to continuous dosing while allowing treatment breaks or intensification. Further evaluation of early response biomarker-guided treatment regimens in prospective trials is warranted.

Plain Language Summary

Lutetium-PSMA therapy is a new therapy for metastatic prostate cancer that is well tolerated and effective. However, not all men respond equally, with some responding very well and others progressing early. Personalising treatments require tools that can accurately measure treatment responses, preferably early in the treatment course, so adjustments to treatment can be made. Lutetium-PSMA can measure tumour sites after each therapy by taking whole body 3D images at 24 h using a small radiation wave from the treatment itself. This is called a SPECT scan. Previous work has shown that both prostate-specific antigen (PSA) response and changes in tumour volume on a SPECT scan can predict how patients will respond to treatment as early as dose 2. This study demonstrates that stratifying how men are treated based on the results of the 6-week SPECT scan and PSA response potentially allows a third of men to have break in treatment and that these men have both longer time to disease progression and OS. Men with an increase in tumour volume and increase in PSA early in treatment (6 weeks) had shorter time to disease progression and OS. Men with early biomarker disease progression were offered alternative treatments early in an attempt to allow the opportunity to allow a more effective potential therapy, if one was available. The study is an analysis of a clinical programme, and was not a prospective trial. As such, there are potential biases that could influence results. Hence, while the study is encouraging for the use of early response biomarkers to guide better treatment decisions, this must be validated in a well-designed clinical trial.

Novel Case of Isolated Peritoneal Carcinomatosis from Metastatic Prostate Cancer Carrying a Pathogenic BRCA Mutation Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

We present the first case of isolated peritoneal carcinomatosis (PC) from prostate cancer carrying a previously unreported pathogenic BRCA2 mutation without other organ involvement. CT showed PC with no extra-peritoneal metastases. Treatment included neoadjuvant chemotherapy, cytoreductive surgery/hyperthermic intraperitoneal chemotherapy (CRS/HIPEC), and adjuvant chemotherapy. Patient is disease-free after 30-months. Germline genetic testing showed BRCA2 c.1813dupA (p.I605Nfs*11) mutation, reported in breast and ovarian cancers. Tumor genomic testing also revealed TMPRSS2, TBX3, and TP53 mutations. Given the comparable presentation and BRCA-mutation profile to ovarian cancer, BRCA2 mutations may contribute to disease phenotypes. CRS/HIPEC may provide long-term outcomes for this unique metastatic pattern.

Liquid Biopsy by Next-Generation Sequencing: a Multimodality Test for Management of Cancer

PURPOSE OF REVIEW

While liquid biopsy is still relatively a new concept, the advent of next-generation sequencing (NGS) technologies has recently generated a revolution in the field and will be the focus of this review.

RECENT FINDINGS

Circulating tumor DNA (ctDNA) derives from tumor cells and provides information about the genetic alterations of tumors. However, ctDNA concentration in plasma can be below the level of detection by conventional methods; therefore, screening for actionable genetic information is challenging. Clinical trials exploring targeted and untargeted sequencing to improve the outcomes of ctDNA detection are showing promising results, having reached a limit of detection as low as 0.001% of ctDNA in a background of normal circulating DNA. Most of the challenges related to the sensitivity of detection of ctDNA have been defeated by dint of NGS-based approaches. Despite all the efforts, these methods are still expensive, time-consuming, and require advanced skills for appropriate interpretation. Nevertheless, the technology is rapidly improving, and the expectations for the implementation of liquid biopsy into the clinical practice in the near future are high.

Prostate-specific antigen dynamics predict individual responses to intermittent androgen deprivation

Intermittent androgen deprivation therapy (IADT) is an attractive treatment for biochemically recurrent prostate cancer (PCa), whereby cycling treatment on and off can reduce cumulative dose and limit toxicities. We simulate prostate-specific antigen (PSA) dynamics, with enrichment of PCa stem-like cell (PCaSC) during treatment as a plausible mechanism of resistance evolution. Simulated PCaSC proliferation patterns correlate with longitudinal serum PSA measurements in 70 PCa patients. Learning dynamics from each treatment cycle in a leave-one-out study, model simulations predict patient-specific evolution of resistance with an overall accuracy of 89% (sensitivity = 73%, specificity = 91%). Previous studies have shown a benefit of concurrent therapies with ADT in both low- and high-volume metastatic hormone-sensitive PCa. Model simulations based on response dynamics from the first IADT cycle identify patients who would benefit from concurrent docetaxel, demonstrating the feasibility and potential value of adaptive clinical trials guided by patient-specific mathematical models of intratumoral evolutionary dynamics.

EMT Markers in Locally-Advanced Prostate Cancer: Predicting Recurrence?

Background: Prostate cancer (PCa) is the second most frequent cause of cancer-related death in men worldwide. It is a heterogeneous disease at molecular and clinical levels which makes its prognosis and treatment outcome hard to predict. The epithelial-to-mesenchymal transition (EMT) marks a key step in the invasion and malignant progression of PCa. We sought to assess the co-expression of epithelial cytokeratin 8 (CK8) and mesenchymal vimentin (Vim) in locally-advanced PCa as indicators of EMT and consequently predictors of the progression status of the disease. Methods: Co-expression of CK8 and Vim was evaluated by immunofluorescence (IF) on paraffin-embedded tissue sections of 122 patients with PCa who underwent radical prostatectomies between 1998 and 2016 at the American University of Beirut Medical Center (AUBMC). EMT score was calculated accordingly and then correlated with the patients' clinicopathological parameters and PSA failure. Results: The co-expression of CK8/Vim (EMT score), was associated with increasing Gleason group. A highly significant linear association was detected wherein higher Gleason group was associated with higher mean EMT score. In addition, the median estimated biochemical recurrence-free survival for patients with < 25% EMT score was almost double that of patients with more than 25%. The validity of this score for prediction of prognosis was further demonstrated using cox regression model. Our data also confirmed that the EMT score can predict PSA failure irrespective of Gleason group, pathological stage, or surgical margins. Conclusion: This study suggests that assessment of molecular markers of EMT, particularly CK8 and Vim, in radical prostatectomy specimens, in addition to conventional clinicopathological prognostic parameters, can aid in the development of a novel system for predicting the prognosis of locally-advanced PCa.

Cell-free DNA in cancer: current insights

BACKGROUND

The field of liquid biopsies in oncology is rapidly expanding, with the application of cell-free circulating tumour DNA (ctDNA) showing promise in this era of precision medicine. Compared with traditional clinical and radiographic tumour monitoring methods, the analysis of ctDNA provides a minimally-invasive and technically feasible approach to assess temporal and spatial molecular evolutions of the tumour landscape. The constantly advancing technological platforms available for ctDNA extraction and analysis allow greater analytical sensitivities than ever before. The potential translational impact of ctDNA as a blood-based biomarker for the identification, characterization and monitoring of cancer has been demonstrated in numerous proof-of-concept studies, with ctDNA analysis beginning to be applied clinically across multiple facets of oncology.

CONCLUSIONS

In this review we discuss the biology, recent advancements, technical considerations and clinical implications of ctDNA in the context of cancer, and highlight important challenges and future directions for the integration of ctDNA into standardised patient care.

Case report: Incidental metastatic prostate cancer with undetectable PSA in pelvic lymphadenectomy

We report a patient that had a prior radical prostatectomy and negative PSA levels for two years and subsequently developed bladder cancer requiring radical cystectomy with mixed lymph nodes on final pathology. The nodes were found to be positive for both metastatic urothelial cell carcinoma and metastatic prostatic adenocarcinoma based on immunohistochemical staining. Treatment for metastatic bladder cancer was pursued after radical cystectomy recovery.

Unusual Presentation of Prostate Cancer Metastatic to the Cricoid Cartilage and Oral Cavity

In Mexico, prostate cancer is the second leading cause of death in men. Prostate cancer usually presents metastasis to the regional lymph nodes and bone. Hereby, we present an unusual case of metastatic prostate cancer, with affectation to the cricoid cartilage and oral cavity, being the first case to have ever been reported in Mexico. A 68-year-old Mexican man was diagnosed with prostate cancer and cribriform architecture histology with low serum level of prostate-specific antigen, debuting with laryngeal stridor. The biopsy came back positive for metastatic prostate carcinoma. During treatment with radiotherapy, metastasis developed to the oral cavity.

Direct Extension of Prostatic Adenocarcinoma Protruding Through the Urethral Meatus

Prostate cancer involving the anterior urethra is rare with few cases describing isolated recurrence to the anterior urethra. This case describes a patient with a history of metastatic prostate cancer who subsequently developed advanced prostate cancer involving the entire urethra with extension from the prostatic urethra to the urethral meatus. This will help future healthcare providers recognize this metastatic pattern as a possibility and explore this option when presented with a bleeding mass at the urethral meatus of unknown origin. It is important for clinicians to realize poorly differentiated prostate cancer may not produce PSA yet still behave aggressively.

c-Myc Antagonises the Transcriptional Activity of the Androgen Receptor in Prostate Cancer Affecting Key Gene Networks

Prostate cancer (PCa) is the most common non-cutaneous cancer in men. The androgen receptor (AR), a ligand-activated transcription factor, constitutes the main drug target for advanced cases of the disease. However, a variety of other transcription factors and signaling networks have been shown to be altered in patients and to influence AR activity. Amongst these, the oncogenic transcription factor c-Myc has been studied extensively in multiple malignancies and elevated protein levels of c-Myc are commonly observed in PCa. Its impact on AR activity, however, remains elusive. In this study, we assessed the impact of c-Myc overexpression on AR activity and transcriptional output in a PCa cell line model and validated the antagonistic effect of c-MYC on AR-targets in patient samples. We found that c-Myc overexpression partially reprogrammed AR chromatin occupancy and was associated with altered histone marks distribution, most notably H3K4me1 and H3K27me3. We found c-Myc and the AR co-occupy a substantial number of binding sites and these exhibited enhancer-like characteristics. Interestingly, c-Myc overexpression antagonised clinically relevant AR target genes. Therefore, as an example, we validated the antagonistic relationship between c-Myc and two AR target genes, KLK3 (alias PSA, prostate specific antigen), and Glycine N-Methyltransferase (GNMT), in patient samples. Our findings provide unbiased evidence that MYC overexpression deregulates the AR transcriptional program, which is thought to be a driving force in PCa.

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c-MYC and AR share one third of chromatin binding with enhancer-like features.

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c-MYC can repress the expression of a subset prostate cancer biomarkers, including PSA.

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c-MYC and AR antagonize the expression of, Glycine N-Methyltransferase (GNMT), responsible for sarcosine biosynthesis.

Prostate cancer is a heterogeneous disease. The most frequently used biomarker in clinical setting, a well described androgen receptor target gene, PSA, still performs poorly in stratifying patients at real risk of death due to the disease. Despite this, therapeutic approaches focus on suppressing androgen receptor signaling. However, this is only one of the recurrent alterations found in patients. This study focuses on c-MYC and the effects of its deregulation in advanced prostate cancer. We find that there is an inverse relationship between established biomarkers expression, including PSA. This inverse relationship could be used in clinics to select beneficial therapeutic approaches for a subset of prostate cancer cases.

Measurement of serum prostate cancer markers using a nanopore thin film based optofluidic chip

Currently used cancer marker for prostate adenocarcinoma (PC), serum prostate-specific antigen (PSA), greatly overestimates PC population. Patients with high PSA levels have to undergo unnecessary but physically painful and expensive procedure such as prostate biopsies repeatedly. The reliability of PC test can be greatly increased by finding a protein that is secreted selectively by malignant, but not normal, prostate cells. A recently discovered novel protein, referred as neuroendocrine marker (NEM), is secreted only by malignant prostate cells and released in blood circulation. Although NEM seems to be significantly more reliable based on the data obtained from a limited cohort, currently available NEM ELISA is not suitable for undertaking a large study. Therefore, the goal of the present study was to develop an alternative, label-free assay system that can reliably measure NEM and PSA in patient samples. Herein an optofluidic chip that can reliably detect PSA as well as NEM in patient samples has been developed. The optofluidic chip, which consists of arrayed nanopore-based sensors fabricated from anodic aluminum oxide (AAO) thin film, offers improved sensitivity upon the optimization of the concentration of the detector antibodies immobilized on the sensor surface. The results demonstrate that the chip is reliable, extremely sensitive and requires just 1 µl of patient serum (or even less) to measure PSA and NEM even in a non-cancer individual. Compared with the traditional ELISA for PSA, the nanopore-based sensor assay is 50-100 fold more sensitive, and offers many advantages such as elimination of labeled antigen, need for sophisticated equipment and highly trained individuals. These advantages, along with the low cost, should make the technology suitable for point-of-care application to screen elderly male populations for PC and to monitor the progress of patients undergoing PC treatment.

Biomarker detection technologies and future directions

Biomarkers play a vital role in disease detection and treatment follow-up. It is important to note that diseases in the early stage are typically treated with the greatest probability of success. However, due to various technical difficulties in current technologies for the detection of biomarkers, the potential of biomarkers is not explored completely. Therefore, the developments of technologies, which can enable the accurate detection of prostate cancer at an early stage with simple, experimental protocols are highly inevitable. This critical review evaluates the current methods and technologies used in the detection of biomarkers. The aim of this article is to provide a comprehensive review covering the advantages and disadvantages of the biomarker detection methods. Future directions for the development of technologies to achieve highly selective and sensitive detection of biomarkers for point-of-care applications are also commented on.