Clinical features of patients who present with metastatic prostate carcinoma and serum prostate-specific antigen (PSA) levels < 10 ng/mL

Early response monitoring during [177Lu]Lu-PSMA I&T therapy with quantitated SPECT/CT predicts overall survival of mCRPC patients: subgroup analysis of a Swiss-wide prospective registry study

PURPOSE

To assess early tumor response with quantitated SPECT/CT and to correlate it with clinical outcome in metastatic castration-resistant prostate cancer (mCRPC) patients treated with 177Lutetium-PSMA I&T therapy.

METHODS

Single-center, observational study, part of the prospective Swiss national cancer registry study investigating the safety and efficacy of [177Lu]Lu-PSMA I&T (EKNZ: 2021-01271) in mCRPC patients treated with at least two cycles of [177Lu]Lu-PSMA I&T 6-weekly. After the first and second cycle quantitated SPECT/CT (Symbia Intevo, Siemens) was acquired 48 h after injection (three fields of view from head to thigh, 5 s/frame) and reconstructed using xQuant® (48i, 1 s, 10-mm Gauss). Image analysis: The PSMA-positive total tumor volumes (TTV) were semi-automatically delineated using a SUV threshold of 3 with MIMencore® (version 7.1.3, Medical Image Merge Software Inc.). Changes in TTV, highest tumor SUVmax, and total tumor SUVmean between cycles 1 and 2 were calculated and grouped into a) stable or decrease and b) increase. Serum PSA levels were assessed at each therapy cycle and at follow-up until progression or death. Changes in TTV, PSA, SUVmax, and SUVmean were correlated with PSA-progression-free survival (PSA-PFS) and the overall survival (OS) using the Kaplan-Meier methodology (log-rank test).

RESULTS

Between 07/2020 and 04/2022, 111 patients were screened and 73 finally included in the data analysis. The median follow-up was 8.9 months (range 1.4-26.6 months). Stable or decreased TTV at cycle 2 was associated with longer OS (hazard ratio (HR) 0.28, 95% confidence interval (CI) 0.09-0.86, p < 0.01). Similar, stable, or decreased PSA was associated with longer OS (HR 0.21; CI 0.07-0.62, p < 0.01) and PSA-PFS (HR 0.34; 95% CI 0.16-0.72, p < 0.01). Combining TTV and PSA will result in an augmented prognostic value for OS (HR 0.09; CI 0.01-0.63; p < 0.01) and for PSA-PFS (HR 0.11; CI 0.02-0.68; p < 0.01). A reduction of SUVmax or SUVmean was not prognostically relevant, neither for OS (p 0.88 and 0.7) nor for PSA-PFS (p 0.73 and 0.62, respectively).

CONCLUSION

Six weeks after initiating [177Lu]Lu-PSMA I&T, TTV and serum PSA appear to be good prognosticators for OS. Combined together, TTV + PSA change demonstrates augmented prognostic value and can better predict PSA-PFS. Larger studies using TTV change prospectively as an early-response biomarker are warranted for implementing management change towards a more personalized clinical practice.

Feasibility of Monitoring Response to Metastatic Prostate Cancer Treatment with a Methylation-Based Circulating Tumor DNA Approach

BACKGROUND

Metastatic prostate cancer (mPCA) poses challenges in treatment response assessment, particularly in cases where prostate-specific antigen (PSA) levels do not reliably indicate a response. Liquid biopsy, focusing on circulating cell-free DNA (ccfDNA) methylation analysis as a proxy for circulating tumor DNA, offers a non-invasive and cost-effective approach. This study explores the potential of two methylation markers, short stature homeobox 2 (SHOX2) and Septin 9 (SEPT9), as on-mPCA-treatment biomarkers.

METHODS

Plasma samples were collected from 11 mPCA patients undergoing various treatments. Quantitative assessment of hypermethylated SHOX2 (mSHOX2) and SEPT9 (mSEPT9) levels in ccfDNA was conducted through methylation-specific real-time PCR. Early and overall dynamics of PSA, mSHOX2, and mSEPT9 were analyzed. Statistical evaluation employed Wilcoxon tests.

RESULTS

mSHOX2 demonstrated a significant decline post-treatment in patients with a radiographic treatment response as well as in an early treatment setting. mSEPT9 and PSA exhibited non-significant declines. In individual cases, biomarker dynamics revealed unique patterns compared to PSA.

DISCUSSION

mSHOX2 and mSEPT9 exhibit dynamics on mPCA treatment. This proof-of-concept study lays the groundwork for further investigation into these markers as valuable additions to treatment response monitoring in mPCA. Further validation in larger cohorts is essential for establishing clinical utility.

Early Detection of Secondary Bladder Urothelial Carcinoma and Disseminated Bone Metastases with Normal Prostate-Specific Antigen Level after Pelvic Salvage Radiotherapy in Prostate Cancer

This report describes the case of a 65-year-old man who presented with gross hematuria and a history of pelvic salvage radiotherapy for prostate cancer. Cystoscopy and transurethral resection of the bladder revealed urothelial carcinoma. Subsequently, disseminated bone metastases were detected with normal prostate-specific antigen (PSA) levels, and palliative radiotherapy and systemic chemotherapy were administered. Because gross hematuria can appear in both acute/chronic cystitis and bladder cancer in patients who have undergone pelvic radiotherapy for prostate cancer, close follow-up along with a detailed evaluation is needed. In addition, because prostate cancer disease progression with normal PSA levels may be associated with specific pathological findings, a detailed evaluation of symptoms and a careful review of pathologic reports are important.

Early Dynamics of Quantitative SEPT9 and SHOX2 Methylation in Circulating Cell-Free Plasma DNA during Prostate Biopsy for Prostate Cancer Diagnosis

Background: The methylation status of Septin 9 (SEPT9) and short stature homeobox 2 (SHOX2) in circulating cell-free DNA (ccfDNA) are validated pan-cancer biomarkers. The present proof-of-concept study aimed to investigate the potential and dynamics of quantitative SEPT9 and SHOX2 methylation in prostate cancer (PCa) patient tissue and ccfDNA during prostate biopsy as a diagnostic tool. Methods: The methylation patterns of SEPT9 and SHOX2 in prostate tissue were analyzed using The Cancer Genome Atlas data set (n = 498 PCa and n = 50 normal adjacent prostate tissue (NAT)). Next, dynamic changes of ccfDNA methylation were quantified in prospectively enrolled patients undergoing prostate biopsy (n = 72), local treatment for PCa (n = 7; radical prostatectomy and radiotherapy) as well as systemic treatment for PCa (n = 6; chemotherapy and 177-Lu-PSMA-therapy). Biomarker levels were correlated with clinicopathological parameters. Results: SEPT9 and SHOX2 were hypermethylated in PCa tissue (p < 0.001) and allowed discrimination of PCa and non-tumor prostate tissue (mSEPT9: AUC 0.87, 95%CI [0.82−0.92]; mSHOX2: AUC 0.89, 95%CI 0.84−0.94). SHOX2 methylation and mRNA levels were significantly higher in PCa tissue and increased with tumor stage and grade, as well as in patients suffering from biochemical recurrence following radical prostatectomy. SEPT9 and SHOX2 ccfDNA methylation allowed distinguishing patients with localized and metastatic disease (p < 0.001 for both). In addition, methylation levels increased shortly after prostate biopsy only in patients with PCa (ΔmSEPT9: p < 0.001 and ΔmSHOX2: p = 0.001). Conclusions: The early dynamics of methylated SEPT9 and SHOX2 in ccfDNA allow differentiation between PCa patients and patients without PCa and is a promising marker for tumor monitoring in the metastatic stage to determine tumor burden under systemic therapy.

[Treatment of primary disease for synchronous metastatic prostate cancer]

The management of early metastatic prostate cancer is based on systemic treatment by androgen deprivation therapy with or without chemotherapy or next-generation anti-androgen therapies. Local treatment of the prostate was initially used only to alleviate local symptoms. However, local radiotherapy of the prostate has been the subject of retrospective and prospective studies in patients with better prognostic factors, particularly in oligometastatic status. The results of these studies support that prostate radiotherapy can prolong the survival of patients with a low metastatic burden. This article states the biological bases, the main published and future published studies aimed to embed this strategy to optimize therapeutic management.

[DRUG-INDUCED INTERSTITIAL LUNG DISEASE DURING COMBINED ANDROGEN BLOCKADE WITH BICALUTAMIDE AND LEUPRORELIN ACETATE FOR PROSTATE CANCER]

We report a case of drug-induced interstitial lung disease as a result of combined androgen blockade. A 75 year-old male was receiving bicalutamide and reuprorelin acetate treatment for advanced prostate cancer. Two weeks after starting therapy, the patient developed dyspnea due to interstitial lung disease. Based on the clinical diagnosis of drug-induced interstitial lung disease, bicalutamide was withdrawn and steroid therapy was initiated. The patient succumbed 6 days later due to respiratory failure. Drug-induced interstitial lung disease following combined androgen blockade is a rare, but potentially serious adverse effect that requires close attention.

The U Shape of Prostate-specific Antigen and Prostate Cancer-specific Mortality in High-grade Metastatic Prostate Adenocarcinoma

BACKGROUND

Accumulated evidence suggests that metastatic prostate cancer (mPCa) with a low prostate-specific antigen (PSA) level may be a unique entity. However, its clinical features and prognosis have not been fully evaluated.

OBJECTIVE

To investigate the clinical features of low-PSA mPCa and the impact of low PSA level on overall survival (OS) and PCa-specific mortality (PCSM) of mPCa.

DESIGN, SETTING, AND PARTICIPANTS

A total of 8479 mPCa patients were retrieved from the Surveillance, Epidemiology, and End Results program (2010-2015). The median follow-up was 18 mo.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Cox regression and Fine-Gray competing risk were used to calculate the hazard ratio (HR) and subdistribution hazard ratio (sHR) for OS and PCSM, respectively.

RESULTS AND LIMITATIONS

A higher rate of T4 stage disease (19.8%) and visceral metastasis (18.2%) and the shortest median OS (34 mo) were observed in mPCa patients with Gleason 8-10 and PSA ≤4ng/ml. In the Cox regression model, PSA ≤4ng/ml was a significant predictor of OS for Gleason 8-10 disease. The distribution of PCSM by PSA was U-shaped for Gleason score 8-10 (PSA 4.1-10ng/ml as the referent), with an adjusted sHR of 1.52 for PSA ≤4.0ng/ml (95% confidence interval: 1.17-1.96) versus 0.99 for PSA 10.1-20ng/ml and 1.35 for PSA >20ng/ml. In contrast, the distribution of PCSM by PSA was linear for Gleason 5-7. Sensitivity analyses showed similar results in Gleason 9-10 and Gleason 10 subgroup. The study is limited by its retrospective design.

CONCLUSIONS

Low PSA, high-grade mPCa has a higher proportion of T4 stage disease, visceral metastasis, and PCSM.

PATIENT SUMMARY

We found that 2.8% of high-grade metastatic prostate cancer has a prostate-specific antigen level ≤4ng/ml at diagnosis. This population has aggressive clinical features and a poor cancer-specific outcome. Our results highlighted this under-reported population, and the management of these patients warrants further research.

Prostate Cancer Metastasis to Thyroid Gland

Metastases to the thyroid gland are rarely encountered in clinical practice. They may originate from various primary sites, mainly kidney, lung, breast, esophagus and uterus. Prostate cancer is one of the most frequent malignancies in men. It generally has a favorable course, and autopsy series have shown occult prostate cancer in many subjects, especially in aged males. However, prostate cancer sometimes exhibits an aggressive behavior and cases with a poor prognosis have been reported. Occasional reports of metastasis from prostate cancer to the thyroid gland have been documented. We describe the case of a 73-year-old patient presenting with thyroid metastasis from long-standing prostate cancer.

Prostate adenocarcinoma metastases to the testis and brain: case report and review of the literature

Prostate cancer is the second most common cancer in men worldwide. While clinicians commonly see metastases to the bones and lymph nodes, it may infrequently spread to more uncommon locations. We report an unusual case of an 83-year-old patient with previously treated prostate adenocarcinoma who presents with symptomatic metastases to the testis and brain in the absence of widely disseminated disease. This case report highlights the importance of including metastatic disease in the differential for patients with a history of prostate cancer and a newly discovered mass until an evaluation of the tissue can be performed.

Lethal Prostate Cancer in the PLCO Cancer Screening Trial

The Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial randomized men to usual care or annual prostate-specific antigen (PSA) screening for 6 yr and digital rectal examination for 4 yr. This trial found no difference between the intervention and usual care arms of the study in the primary end point of prostate cancer (PCa)-specific mortality. The PLCO trial results have had a major impact on health policy and the rate of PSA screening in the United States. We analyzed the 13-yr screening and outcomes data from the 151 participants who died of PCa in the screening arm of the trial to better understand how randomization to screening failed to prevent PCa death in these men. We found that of these men, 81 (53.6%) either were never screened as part of the trial or had an initial positive screen. Only 17 (11.3%) of those who died reached year 6 of the trial with a PSA <4.0 ng/ml. The men who died in the screening arm were also older at study entry than the average PLCO participant (66 vs 62 yr; p < 0.001). Our analysis should inform the interpretation of the PLCO trial and provide insight into future trial design.

A prospective study of nomogram-based adaptation of prostate radiotherapy target volumes

BACKGROUND

A prospective clinical trial was conducted to evaluate the feasibility of a novel approach to the treatment of patients with high risk prostate cancer (HRPC) through the use of a nomogram to tailor radiotherapy target volumes.

METHODS

Twenty seven subjects with HRPC were treated with a mildly hypofractionated radiotherapy regimen using image-guided IMRT technique between Jun/2013-Jan/2015. A set of validated prognostic factors were inputted into the Memorial-Sloan-Kettering Cancer Center (MSKCC) prostate cancer nomogram to estimate risk of loco-regional spread (LRS). The nomogram risk estimates for extra-capsular extension (ECE), seminal vesicles involvement (SVI), and pelvic lymph nodes involvement (LNI) were used to adapt radiotherapy treatment volumes based on a risk threshold of ≥15 % in all cases. A planning guide was used to delineate target volumes and organs at risk (OAR). Up to three dose levels were administered over 28 fractions; 70Gy for gross disease in the prostate +/- seminal vesicles (2.5Gy/fraction), 61.6Gy for subclinical peri-prostatic disease (2.2Gy/fraction) and 50.4Gy to pelvic nodes (1.8Gy/fraction). Data regarding protocol adherence, nomogram use, radiotherapy dose distribution, and acute toxicity were collected.

RESULTS

Nomogram use 100 % of patients were treated for ECE, 88.9 % for SVI, and 70.4 % for LNI. The three areas at risk of LRS were appropriately treated according to the study protocol in 98.8 % cases. The MSKCC nomogram estimates for LRS differed significantly between the time of recruitment and analysis. Contouring protocol compliance Compliance with the trial contouring protocol for up to seven target volumes was 93.0 % (159/171). Compliance with protocol for small bowel contouring was poor (59.3 %). Dose constraints compliance Compliance with dose constraints for target volumes was 97.4 % (191/196). Compliance with dose constraints for OAR was 88.2 % (285/323). Acute toxicity There were no grade 3 acute toxicities observed. 20/27 (74.1 %) and 6/27 (22.2 %) patients experienced a grade 2 genitourinary and gastrointestinal toxicity respectively.

CONCLUSIONS

We have demonstrated the feasibility of this novel risk-adapted radiation treatment protocol for HRPC. This study has identified key learning points regarding this approach, including the importance of standardization and updating of risk quantification tools, and the utility of an observer to verify their correct use.

TRIAL REGISTRATION

ClincialTrials.gov identifier NCT01418040 . Hunter New England Human Research Ethics Committee (HNEHREC) reference number 12/08/15/4.02.

Solitary recurrence of castration-resistant prostate cancer with low or undetectable levels of prostate specific antigen salvaged with local ablative radiation therapy: A case report

Prostate cancer recurrences are usually first detected by increased levels of prostate specific antigen (PSA), and systemic therapy is often initiated if distant metastasis is confirmed. However, low or nearly undetectable levels of PSA in the modern era of ultrasensitive PSA assay may be difficult to interpret in patients with a history of prostate cancer. Deciding whether to initiate additional systemic therapy in limited indolent metastatic disease while balancing the quality of life of the patient and ensuring the oncologic control of the disease may be challenging. In the present study, the case of a biopsy-confirmed solitary spine recurrence of prostate cancer with nearly undetectable but persistent levels of PSA (0.05 ng/ml) is reported. Treatment of the recurrence with local ablative radiotherapy improved the pain experienced by the patient, and reduced his levels of PSA to undetectable limits (<0.05 ng/ml). Repeated imaging analysis, PSA assay and clinical assessment demonstrated durable control of the disease without the requirement for additional systemic treatments. The present case highlighted the importance of initiating appropriate work-up according to the clinical scenario. Local treatment for solitary or oligometastatic recurrence of prostate cancer may enhance the effectiveness of current therapeutic strategies and benefit certain patients.

A review of solutions for diagnostic accuracy studies with an imperfect or missing reference standard

OBJECTIVE

In diagnostic accuracy studies, the reference standard may be imperfect or not available in all patients. We systematically reviewed the proposed solutions for these situations and generated methodological guidance.

STUDY DESIGN AND SETTING

Review of methodological articles.

RESULTS

We categorized the solutions into four main groups. The first group includes methods that impute or adjust for missing data on the reference standard. The second group consists of methods that correct estimates of accuracy obtained with an imperfect reference standard. In the third group a reference standard is constructed by combining multiple test results through a predefined rule, based on a consensus procedure, or through statistical modeling. In the fourth group, the diagnostic accuracy paradigm is abandoned in favor of validation studies that relate index test results to relevant clinical data, such as history, future clinical events, and response to therapy.

CONCLUSION

Most of the methods try to impute, adjust, or construct a reference standard. In situations that deviate only marginally from the classical diagnostic accuracy paradigm, these are valuable methods. In cases where an acceptable reference standard does not exist, the concept of clinical test validation may provide an alternative paradigm to evaluate a diagnostic test.

Evolving perspectives of the role of novel agents in androgen-independent prostate cancer

Metastatic androgen-independent prostate cancer presents an intriguing clinical challenge, with a subtle interaction between hormone-responsive and refractory tumor cell elements. The treatment of advanced prostate carcinoma, which had remained stagnant for several decades following the understanding of the link between androgenic stimulation and carcinogenesis, has now started to make steady headway with chemotherapy and targeted approaches. Metastatic prostate cancer is almost always treated with initial androgen deprivation, in various forms. However, despite such treatment androgen-independent prostate cancer cells eventually emerge and progress to threaten life. The therapeutic objectives for treatment of metastatic prostate cancer are to maintain the quality of life and prolong survival. The out-dated nihilistic dogma of deferring chemotherapy until the most advanced stages in advanced prostate cancer is now falling by the wayside with the development of newer effective, tolerable agents.

Lineage dependency and lineage-survival oncogenes in human cancer

Although cell-lineage and differentiation models dominate tumour classification and treatment, the recognition that cancer is also a genomic disease has prompted a reconfiguration of cancer taxonomies according to molecular criteria. Recent evidence indicates that a synthesis of lineage-based and genetic paradigms might offer new insights into crucial and therapeutically pliable tumour dependencies. For example, MITF (microphthalmia-associated transcription factor), which is a master regulator of the melanocyte lineage, might become a melanoma oncogene when deregulated in certain genetic contexts. MITF and other lineage-survival genes therefore implicate lineage dependency (or lineage addiction) as a newly recognized mechanism that is affected by tumour genetic alterations.

Prostatic meningeal carcinomatosis with low serum level of prostate-specific antigen

Less than 1% of patients with metastatic prostate cancer present with abnormally low serum levels of prostate-specific antigen (PSA). Furthermore, cases of prostatic metastases to the meninges with a low serum level of PSA are extremely rare. The present report describes a patient with prostatic meningeal carcinomatosis and low serum PSA levels.

Tumour markers for managing men who present with metastatic prostate cancer and serum prostate-specific antigen levels of <10 ng/mL

OBJECTIVE

To define immunohistochemical features of the primary cancers that might help in the differential diagnosis and monitoring of treatment in men presenting with metastatic prostate cancer and low serum levels of prostate-specific antigen (PSA), who can be difficult to diagnose and manage.

PATIENTS AND METHODS

Paraffin blocks of prostate biopsies were obtained for 33 patients presenting with untreated metastatic prostate cancer and serum PSA levels of <10 ng/mL. Sections were immunostained for PSA, prostatic acid phosphatase (PAP), prostate-specific membrane antigen (PSMA), androgen receptor (AR), chromogranin A and CD 56.

RESULTS

The combined Gleason scores were 8-10 in 25 men (76%) and 6 or 7 in the other eight (24%). Morphologically, there were no neuroendocrine features. PSA immunostaining was equivocal in 12 (36%) cases and in a further 19 (58%) was strong but focal and could be missed on biopsy sampling. PSMA was expressed in 90% of cases, and staining was widely distributed in nine of the 12 in which PSA staining was equivocal. There was strong AR expression in 30 (91%) cases and it was present in areas where PSA was absent.

CONCLUSION

In this patient group, immunohistochemical assessments of PSMA and AR are potentially useful as diagnostic markers.