A multi-cancer early detection blood test using machine learning detects early-stage cancers lacking USPSTF-recommended screening

US Preventive Services Task Force (USPSTF) guidelines recommend single-cancer screening for select cancers (e.g., breast, cervical, colorectal, lung). Advances in genome sequencing and machine learning have facilitated the development of blood-based multi-cancer early detection (MCED) tests intended to complement single-cancer screening. MCED tests can interrogate circulating cell-free DNA to detect a shared cancer signal across multiple tumor types. We report real-world experience with an MCED test that detected cancer signals in three individuals subsequently diagnosed with cancers of the ovary, kidney, and head/neck that lack USPSTF-recommended screening. These cases illustrate the potential of MCED tests to detect early-stage cancers amenable to cure.

Genome assembly of Pseudomonas sp. strain SED1T, a psychrotolerant bacterium isolated from Deception Glacier (Washington, USA)

Strain SED1T was isolated from glacial samples collected on Mount Deception, Washington, USA. Genome sequencing and assembly identified a DNA G + C content of 60.4 mol% with 6,125 predicted proteins. Analysis by the Type Strain Genome Server is consistent with the isolate representing a previously undescribed species in the genus Pseudomonas.

Spatial organization of bacterial sphingolipid synthesis enzymes

Sphingolipids are produced by nearly all eukaryotes where they play significant roles in cellular processes such as cell growth, division, programmed cell death, angiogenesis, and inflammation. While it was previously believed that sphingolipids were quite rare among bacteria, bioinformatic analysis of the recently identified bacterial sphingolipid synthesis genes suggests that these lipids are likely to be produced by a wide range of microbial species. The sphingolipid synthesis pathway consists of three critical enzymes. Serine palmitoyltransferase catalyzes the condensation of serine with palmitoyl-CoA (or palmitoyl-acyl carrier protein), ceramide synthase adds the second acyl chain, and a reductase reduces the ketone present on the long-chain base. While there is general agreement regarding the identity of these bacterial enzymes, the precise mechanism and order of chemical reactions for microbial sphingolipid synthesis is more ambiguous. Two mechanisms have been proposed. First, the synthesis pathway may follow the well characterized eukaryotic pathway in which the long-chain base is reduced prior to the addition of the second acyl chain. Alternatively, our previous work suggests that addition of the second acyl chain precedes the reduction of the long-chain base. To distinguish between these two models, we investigated the subcellular localization of these three key enzymes. We found that serine palmitoyltransferase and ceramide synthase are localized to the cytoplasm whereas the ceramide reductase is in the periplasmic space. This is consistent with our previously proposed model wherein the second acyl chain is added in the cytoplasm prior to export to the periplasm where the lipid molecule is reduced.

Prostate Cancer Progression Relies on the Mitotic Kinase Citron Kinase

Prostate cancer remains the second leading cause of cancer death in men in Western cultures. A deeper understanding of the mechanisms by which prostate cancer cells divide to support tumor growth could help devise strategies to overcome treatment resistance and improve survival. Here, we identified that the mitotic AGC family protein kinase citron kinase (CIT) is a pivotal regulator of prostate cancer growth that mediates prostate cancer cell interphase progression. Increased CIT expression correlated with prostate cancer growth induction and aggressive prostate cancer progression, and CIT was overexpressed in prostate cancer compared with benign prostate tissue. CIT overexpression was controlled by an E2F2-Skp2-p27 signaling axis and conferred resistance to androgen-targeted treatment strategies. The effects of CIT relied entirely on its kinase activity. Conversely, CIT silencing inhibited the growth of cell lines and xenografts representing different stages of prostate cancer progression and treatment resistance but did not affect benign epithelial prostate cells or nonprostatic normal cells, indicating a potential therapeutic window for CIT inhibition. CIT kinase activity was identified as druggable and was potently inhibited by the multikinase inhibitor OTS-167, which decreased the proliferation of treatment-resistant prostate cancer cells and patient-derived organoids. Isolation of the in vivo CIT substrates identified proteins involved in diverse cellular functions ranging from proliferation to alternative splicing events that are enriched in treatment-resistant prostate cancer. These findings provide insights into the regulation of aggressive prostate cancer cell behavior by CIT and identify CIT as a functionally diverse and druggable driver of prostate cancer progression.

SIGNIFICANCE

The poorly characterized protein kinase citron kinase is a therapeutic target in prostate cancer that drives tumor growth by regulating diverse substrates, which control several hallmarks of aggressive prostate cancer progression. See related commentary by Mishra et al., p. 4008.

Characterizing prostate cancer risk through multi-ancestry genome-wide discovery of 187 novel risk variants

The transferability and clinical value of genetic risk scores (GRSs) across populations remain limited due to an imbalance in genetic studies across ancestrally diverse populations. Here we conducted a multi-ancestry genome-wide association study of 156,319 prostate cancer cases and 788,443 controls of European, African, Asian and Hispanic men, reflecting a 57% increase in the number of non-European cases over previous prostate cancer genome-wide association studies. We identified 187 novel risk variants for prostate cancer, increasing the total number of risk variants to 451. An externally replicated multi-ancestry GRS was associated with risk that ranged from 1.8 (per standard deviation) in African ancestry men to 2.2 in European ancestry men. The GRS was associated with a greater risk of aggressive versus non-aggressive disease in men of African ancestry (P = 0.03). Our study presents novel prostate cancer susceptibility loci and a GRS with effective risk stratification across ancestry groups.

Intratumoral androgen biosynthesis associated with 3β-hydroxysteroid dehydrogenase 1 promotes resistance to radiotherapy in prostate cancer

Half of all men with advanced prostate cancer (PCa) inherit at least 1 copy of an adrenal-permissive HSD3B1 (1245C) allele, which increases levels of 3β-hydroxysteroid dehydrogenase 1 (3βHSD1) and promotes intracellular androgen biosynthesis. Germline inheritance of the adrenally permissive allele confers worse outcomes in men with advanced PCa. We investigated whether HSD3B1 (1245C) drives resistance to combined androgen deprivation and radiotherapy. Adrenally permissive 3βHSD1 enhanced resistance to radiotherapy in PCa cell lines and xenograft models engineered to mimic the human adrenal/gonadal axis during androgen deprivation. The allele-specific effects on radiosensitivity were dependent on availability of DHEA, the substrate for 3βHSD1. In lines expressing the HSD3B1 (1245C) allele, enhanced expression of DNA damage response (DDR) genes and more rapid DNA double-strand break (DSB) resolution were observed. A correlation between androgen receptor (AR) expression and increased DDR gene expression was confirmed in 680 radical prostatectomy specimens. Treatment with the nonsteroidal antiandrogen enzalutamide reversed the resistant phenotype of HSD3B1 (1245C) PCa in vitro and in vivo. In conclusion, 3βHSD1 promotes prostate cancer resistance to combined androgen deprivation and radiotherapy by upregulating DNA DSB repair. This work supports prospective validation of early combined androgen blockade for high-risk men harboring the HSD3B1 (1245C) allele.

Blood-based tests for multicancer early detection (PATHFINDER): a prospective cohort study

BACKGROUND

Multicancer early detection (MCED) blood tests can detect a cancer signal from circulating cell-free DNA (cfDNA). PATHFINDER was a prospective cohort study investigating the feasibility of MCED testing for cancer screening.

METHODS

In this prospective cohort study done in oncology and primary care outpatient clinics at seven US health networks, a convenience sample of adults aged 50 years or older without signs or symptoms of cancer consented to MCED testing. We collected blood, analysed cfDNA, and returned results to participants' doctors. If a methylation signature indicative of cancer was detected, predicted cancer signal origin(s) informed diagnostic assessment. The primary outcome was time to, and extent of, diagnostic testing required to confirm the presence or absence of cancer. This trial is registered at ClinicalTrials.gov, NCT04241796, and is completed.

FINDINGS

Between Dec 12, 2019, and Dec 4, 2020, we recruited 6662 participants. 4204 (63·5%) of 6621 participants with analysable results were women, 2417 (36·5%) were men, and 6071 (91·7%) were White. A cancer signal was detected in 92 (1·4%) of 6621 participants with analysable results. 35 (38%) participants were diagnosed with cancer (true positives) and 57 (62%) had no cancer diagnosis (false positives). Excluding two participants whose diagnostic assessments began before MCED test results were reported, median time to diagnostic resolution was 79 days (IQR 37-219): 57 days (33-143) in true-positive and 162 days (44-248) in false-positive participants. Most participants had both laboratory tests (26 [79%] of 33 with true-positive results and 50 [88%] of 57 with false-positive results) and imaging (30 [91%] of 33 with true-positive results and 53 [93%] of 57 with false-positive results). Fewer procedures were done in participants with false-positive results (17 [30%] of 57) than true-positive results (27 [82%] of 33) and few had surgery (one with a false-positive result and three with a true-positive result).

INTERPRETATION

This study supports the feasibility of MCED screening for cancer and underscores the need for further research investigating the test's clinical utility.

FUNDING

GRAIL.

Elevated periprostatic venous testosterone correlates with prostate cancer progression after radical prostatectomy

BACKGROUNDGenerally, clinical assessment of gonadal testosterone (T) in human physiology is determined using concentrations measured in peripheral blood. Prostatic T exposure is similarly thought to be determined from peripheral T exposure. Despite the fact that androgens drive prostate cancer, peripheral T has had no role in the clinical evaluation or treatment of men with localized prostate cancer.METHODSTo assess the role of local androgen delivery in prostate cancer, we obtained blood from the (periprostatic) prostatic dorsal venous complex in 266 men undergoing radical prostatectomy from July 2014 to August 2021 and compared dorsal T (DT) levels with those in circulating peripheral blood (PT) and prostatic tissue. Comprehensive targeted steroid analysis and unbiased metabolomics analyses were performed. The association between the DT/PT ratio and progression-free survival after prostatectomy was assessed.RESULTSSurprisingly, in some men, DT levels were enriched several-fold compared with PT levels. For example, 20% of men had local T concentrations that were at least 2-fold higher than peripheral T concentrations. Isocaproic acid, a byproduct of androgen biosynthesis, and 17-OH-progesterone, a marker of intratesticular T, were also enriched in the dorsal vein of these men, consistent with testicular shunting. Men with enriched DT had higher rates of prostate cancer recurrence. DT/PT concentration ratios predicted worse outcomes even when accounting for known clinical predictors.CONCLUSIONSThese data suggest that a large proportion of men have a previously unappreciated exposure to an undiluted and highly concentrated T supply. Elevated periprostatic T exposure was associated with worse clinical outcomes after radical prostatectomy.FUNDINGNational Cancer Institute (NCI), NIH grants R01CA172382, R01CA236780, R01CA261995, R01CA249279, and R50CA251961; US Army Medical Research and Development Command grants W81XWH2010137 and W81XWH-22-1-0082.

Dying To Find Out: The Cost of Time at the Dawn of the Multicancer Early Detection Era

Cancer is a significant burden worldwide that adversely impacts life expectancy, quality of life, health care costs, and workforce productivity. Although currently recommended screening tests for individual cancers reduce mortality, they detect only a minority of all cancers and sacrifice specificity for high sensitivity, resulting in a high cumulative rate of false positives. Blood-based multicancer early detection tests (MCED) based on next-generation sequencing (NGS) and other technologies hold promise for broadening the number of cancer types detected in screened populations and hope for reducing cancer mortality. The promise of this new technology to improve cancer detection rates and make screening more efficient at the population level demands the development of novel trial designs that accelerate clinical adoption. Carefully designed clinical trials are needed to address these issues.

Performance of a Cell-Free DNA-Based Multi-cancer Detection Test in Individuals Presenting With Symptoms Suspicious for Cancers

PURPOSE

A multi-cancer detection test using a targeted methylation assay and machine learning classifiers was validated and optimized for screening in prospective, case-controlled Circulating Cell-free Genome Atlas (ClinicalTrials.gov identifier: NCT02889978) substudy 3. Here, we report test performance in a subgroup of participants with symptoms suspicious for cancer to assess the test's ability to potentially facilitate efficient diagnostic evaluation in symptomatic individuals.

METHODS

We evaluated test performance (sensitivity, specificity, and accuracy of cancer signal origin [CSO] prediction accuracy) in participants with clinically presenting cancers (CPCs) and noncancer with underlying medical conditions and among two subgroups (65 years and older and GI cancers). Overall survival (OS) of participants who had a cancer signal detected/not detected was compared with SEER-based expected survival.

RESULTS

A total of 2,036 cancer and 1,472 noncancer participants were included. Specificity was high in all noncancer participants (99.5% [95% CI, 98.4 to 99.8]). In participants with CPCs, the overall sensitivity was 64.3% (95% CI, 62.2 to 66.4) and the overall accuracy of CSO prediction in true positives was 90.3%. For GI cancers, the overall sensitivity was 84.1% (95% CI, 80.6 to 87.1). In participants 65 years and older, test performance was similar to that of all participants. Individuals with cancers not detected had a significantly better OS than that expected from SEER (P < .01).

CONCLUSION

This test detected a cancer signal with high specificity and CSO prediction accuracy and moderate sensitivity in symptomatic individuals, with especially high performance in participants with GI cancers. The survival analysis implied that the cancers not detected were less clinically aggressive than cancers detected by the test, providing prognostic insights to physicians. This multi-cancer detection test could facilitate efficient workup and stratify cancer risk in symptomatic individuals.

Evidence of Novel Susceptibility Variants for Prostate Cancer and a Multiancestry Polygenic Risk Score Associated with Aggressive Disease in Men of African Ancestry

BACKGROUND

Genetic factors play an important role in prostate cancer (PCa) susceptibility.

OBJECTIVE

To discover common genetic variants contributing to the risk of PCa in men of African ancestry.

DESIGN, SETTING, AND PARTICIPANTS

We conducted a meta-analysis of ten genome-wide association studies consisting of 19378 cases and 61620 controls of African ancestry.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Common genotyped and imputed variants were tested for their association with PCa risk. Novel susceptibility loci were identified and incorporated into a multiancestry polygenic risk score (PRS). The PRS was evaluated for associations with PCa risk and disease aggressiveness.

RESULTS AND LIMITATIONS

Nine novel susceptibility loci for PCa were identified, of which seven were only found or substantially more common in men of African ancestry, including an African-specific stop-gain variant in the prostate-specific gene anoctamin 7 (ANO7). A multiancestry PRS of 278 risk variants conferred strong associations with PCa risk in African ancestry studies (odds ratios [ORs] >3 and >5 for men in the top PRS decile and percentile, respectively). More importantly, compared with men in the 40-60% PRS category, men in the top PRS decile had a significantly higher risk of aggressive PCa (OR = 1.23, 95% confidence interval = 1.10-1.38, p = 4.4 × 10-4).

CONCLUSIONS

This study demonstrates the importance of large-scale genetic studies in men of African ancestry for a better understanding of PCa susceptibility in this high-risk population and suggests a potential clinical utility of PRS in differentiating between the risks of developing aggressive and nonaggressive disease in men of African ancestry.

PATIENT SUMMARY

In this large genetic study in men of African ancestry, we discovered nine novel prostate cancer (PCa) risk variants. We also showed that a multiancestry polygenic risk score was effective in stratifying PCa risk, and was able to differentiate risk of aggressive and nonaggressive disease.

Characterization of an evolutionarily distinct bacterial ceramide kinase from Caulobacter crescentus

A common feature among nearly all Gram-negative bacteria is the requirement for lipopolysaccharide (LPS) in the outer leaflet of the outer membrane. LPS provides structural integrity to the bacterial membrane which aids bacteria in maintaining their shape and acts as a barrier from environmental stress and harmful substances such as detergents and antibiotics. Recent work has demonstrated that Caulobacter crescentus can survive without LPS due to the presence of the anionic sphingolipid ceramide-phosphoglycerate. Based on genetic evidence, we predicted that protein CpgB functions as a ceramide kinase and performs the first step in generating the phosphoglycerate head group. Here, we characterized the kinase activity of recombinantly expressed CpgB and demonstrated that it can phosphorylate ceramide to form ceramide 1-phosphate. The pH optimum for CpgB was 7.5, and the enzyme required Mg²⁺ as a cofactor. Mn²⁺, but not other divalent cations, could substitute for Mg²⁺. Under these conditions, the enzyme exhibited typical Michaelis-Menten kinetics with respect to NBD-C6-ceramide (K_m,app=19.2 ± 5.5 μM; V_max,app=2590 ± 230 pmol/min/mg enzyme) and ATP (K_m,app=0.29 ± 0.07 mM; V_max,app=10100 ± 996 pmol/min/mg enzyme). Phylogenetic analysis of CpgB revealed that CpgB belongs to a new class of ceramide kinases which is distinct from its eukaryotic counterpart; furthermore, the pharmacological inhibitor of human ceramide kinase (NVP-231) had no effect on CpgB. The characterization of a new bacterial ceramide kinase opens avenues for understanding the structure and function of the various microbial phosphorylated sphingolipids.

Using IsoPSA With Prostate Imaging Reporting and Data System Score May Help Refine Biopsy Decision Making in Patients With Elevated PSA

OBJECTIVE

To assess how IsoPSA, a structure-based serum assay which has been prospectively validated in detecting clinically significant prostate cancer (csPCa), can help the biopsy decision process when combined with the prostate imaging reporting and data systems (PI-RADS).

MATERIALS AND METHODS

This was a single-center retrospective review of prospectively collected data on patients receiving IsoPSA testing for elevated PSA (>4.0ng/mL). Patients were included if they had received an IsoPSA test and prostate MRI within 1 year of IsoPSA testing, and subsequently underwent prostate biopsy. Multivariable logistic regression was used to identify predictors of (csPCa, ie, GG ≥ 2) on biopsy. Predictive probabilities for csPCa at biopsy were generated using IsoPSA and various PI-RADS scores.

RESULTS

Two hundred and 7 patients were included. Twenty-two percent had csPCa. Elevated IsoPSA ratio (defined as ≥6.0) (OR: 5.06, P = .015) and a PI-RADS 4-5 (OR: 6.37, P <.001) were significant predictors of csPCa. The combination of elevated IsoPSA ratio and PI-RADS 4-5 lesion had the highest area under the curve (AUC) (AUC: 0.83, P <.001). The predicted probability of csPCa when a patient had a negative or equivocal MRI (PI-RADS 1-3) and a low IsoPSA ratio (≤6) was <5%.

CONCLUSION

The combination of PI-RADS with IsoPSA ratios may help refine the biopsy decision-making process. In our cohort, a negative or equivocal MRI with a low IsoPSA may provide a low enough predicted probability to omit biopsy in such patients.

Mechanism of Tumor-Platelet Communications in Cancer

BACKGROUND

Thrombosis is one of the main complications in cancer patients often leading to mortality. However, the mechanisms underlying platelet hyperactivation are poorly understood.

METHODS AND RESULTS

Murine and human platelets were isolated and treated with small extracellular vesicles (sEVs) from various cancer cell lines. We demonstrate that platelets very effectively take up sEVs from aggressive prostate cancer cells. The process of uptake is fast, proceeds effectively in circulation in mice, and is mediated by the abundant sEV-membrane protein-CD63. The uptake of cancer-sEVs leads to the accumulation of cancer cell-specific RNA in platelets in vitro and in vivo. The human prostate cancer-sEV-specific RNA marker PCA3 is detected in platelets of ~70% of prostate cancer patients. This was markedly reduced after prostatectomy. In vitro studies showed that platelet uptake of cancer-sEVs induces strong platelet activation in a CD63-RPTPα (receptor-like protein tyrosine phosphatase alpha)-dependent manner. In contrast to physiological agonists ADP and thrombin, sEVs activate platelets via a noncanonical mechanism dependent upon active translation. Intravital studies demonstrated accelerated thrombosis both in murine tumor models and in mice that received intravenous injections of cancer-sEVs. The prothrombotic effects of sEVs were rescued by blocking CD63.

CONCLUSIONS

Tumors communicate with platelets by means of sEVs, which deliver cancer markers and activate platelets in a CD63-dependent manner leading to thrombosis. This emphasizes the diagnostic and prognostic value of platelet-associated cancer markers and identifies new pathways for intervention.

Characterization of an evolutionarily distinct bacterial ceramide kinase from Caulobacter crescentus

A common feature among nearly all Gram-negative bacteria is the requirement for lipopolysaccharide (LPS) in the outer leaflet of the outer membrane. LPS provides structural integrity to the bacterial membrane which aids bacteria in maintaining their shape and acts as a barrier from environmental stress and harmful substances such as detergents and antibiotics. Recent work has demonstrated that Caulobacter crescentus can survive without LPS due to the presence of the anionic sphingolipid ceramide-phosphoglycerate. Based on genetic evidence, we predicted that protein CpgB functions as a ceramide kinase and performs the first step in generating the phosphoglycerate head group. Here, we characterized the kinase activity of recombinantly expressed CpgB and demonstrated that it can phosphorylate ceramide to form ceramide 1-phosphate. The pH optimum for CpgB was 7.5, and the enzyme required Mg ²⁺ as a cofactor. Mn ²⁺ , but not other divalent cations, could substitute for Mg ²⁺ . Under these conditions, the enzyme exhibited typical Michaelis-Menten kinetics with respect to NBD-C6-ceramide (K _m,app =19.2 ± 5.5 μM; V _max,app =2586.29 ± 231.99 pmol/min/mg enzyme) and ATP (K _m,app =0.29 ± 0.07 mM; V _max,app =10067.57 ± 996.85 pmol/min/mg enzyme). Phylogenetic analysis of CpgB revealed that CpgB belongs to a new class of ceramide kinases which is distinct from its eukaryotic counterpart; furthermore, the pharmacological inhibitor of human ceramide kinase (NVP-231) had no effect on CpgB. The characterization of a new bacterial ceramide kinase opens avenues for understanding the structure and function of the various microbial phosphorylated sphingolipids.

The combination of prostate MRI PI-RADS scoring system and a genomic classifier is associated with pelvic lymph node metastasis at the time of radical prostatectomy

OBJECTIVE

Pelvic lymph node metastasis (PLNM) at the time of radical prostatectomy (RP) portends an unfavorable prognosis in prostate cancer patients. Conventional and advanced imaging remains limited in its ability to detect PLNM. We sought to evaluate the combination of a genomic classifier Decipher with Prostate Imaging Reporting and Data System (PI-RADS) scores in improving the detection of PLNM.

METHODS

A retrospective review was performed of patients whom underwent RP, Decipher analysis, and pre-operative prostate MRI. Categorical variables were compared using Pearson chi-squareχ2 tests. Quantitative variables were assessed with Wilcoxon rank-sum tests. Multivariable logistic regression was used to identify predictors of PLNM on final pathology.

RESULTS

In total, 202 patients were included in the analysis, 23 of whom (11%) had PLNM. Patients with PLNM had higher median Decipher scores (0.73) than those without PLNM (0.61; p = 0.003). Patients with PLNM were more likely to demonstrate PI-RADS scores ≥ 4 (96%) than those without PLNM (74%; p = 0.012). Logistic regression demonstrated an interaction between Decipher score with PI-RADS score ≥4 (OR = 20.41; 95% CI, 2.10-198.74; p = 0.009) The combination demonstrated an area under the curve (AUC) of 0.73 (95% CI, 0.63-0.82; p < 0.001) for predicting PLNM.

CONCLUSION

The combination of elevated Decipher genomic score (≥ 0.6) and clinically significant PI-RADS score (≥ 4) is associated with PLNM at the time of RP in a modern high-risk cohort of patients with PCaprostate cancer.

ADVANCES IN KNOWLEDGE

Prostate MRI and genomic testing may help identify patients with adverse pathology.

Use of IsoPSA with prostate MRI PIRADS score in biopsy decision making in patients with elevated PSA

388

Background: IsoPSA is prospectively validated to be superior to PSA and percent free PSA in predicting prostate cancer (PCa) as well as clinically significant prostate cancer. We sought to evaluate the use of IsoPSA in combination with prostate magnetic resonance imaging (MRI) and the prostate imaging reporting and data systems (PIRADS) on predicting either benign/indolent or csPCA at biopsy. Methods: This was a single center retrospective review of prospectively collected patient data that included all patients who underwent IsoPSA testing, preoperative prostate MRI and prostate biopsy from 2019-2021. Chi Squared analysis was used to assess for associations between a binary classification of low (<6) or elevated (>6) IsoPSA index, in combination with PIRADS scores in predicting either indolent/benign or csPCa at biopsy. Logistic regression was used to explore independent predictors of csPCa. Receiver Operating Curve (ROC) analysis was completed with areas under the curve (AUC) for IsoPSA and PIRADS scores, both alone and in combination. Predictive probabilities were assessed using combinations of IsoPSA thresholds and PIRADS scores. Results: 207 patients met inclusion criteria. Among patients with a negative MRI, low IsoPSA index was associated with a lower chance of csPCa compared to those with elevated IsoPSA (2% vs 15%, p<0.018). For those with a PIRADS 4-5 lesion, elevated IsoPSA index was associated with a higher chance of csPCa at biopsy compared to a low IsoPSA index (49% vs 19%, p=0.05). On multivariate analysis, elevated IsoPSA and PIRADS 4-5 were independent predictors of csPCa (p<0.001). Similarly, low IsoPSA index and negative MRI were independent predictors of benign/indolent disease at biopsy (p<0.001). Using predictive probabilities, the combination of PIRADS 4-5 with elevated IsoPSA was associated with the highest risk of csPCa (48%) and the highest AUC (0.83) for predicting csPCa. This AUC value was superior to either marker alone (0.76, 0.76) and total PSA alone (0.57) (p<0.001). Conclusions: The combination of elevated IsoPSA with adverse PIRADS score (4-5) is associated with a 48% predicted probability of csPCa at biopsy with an AUC of 0.83, which was more accurate than either marker alone. A low IsoPSA in combination with a negative MRI resulted in a 98% chance of benign/indolent disease at biopsy. These findings may prove useful for the practicing Urologist and may help guide discussions regarding the need for biopsy when interpreting various IsoPSA/PIRADS combinations. [Table: see text]

BMX inhibition and HSD3B1-driven resistance in prostate cancer in the Maverick trial

144

Background: Kinase inhibitors have been ineffective in prostate cancer and have no known role in androgen biosynthesis. Inheritance of the adrenal-permissive HSD3B1(1245C) allele encodes a 3βHSD1 enzyme missense that up-regulates the rate-limiting step of androgen biosynthesis from non-gonadal precursor steroids and confers poor clinical outcomes in castration-resistant prostate cancer (CRPC). About half of all men with prostate cancer inherit the adrenal-permissive HSD3B1 allele. Multiple clinical studies demonstrate that adrenal-permissive HSD3B1 allele inheritance confers more rapid progression on ADT and others also suggest worse CRPC outcomes even after treatment with abiraterone or enzalutamide. However, there is no known method to clinically block 3βHSD1. Furthermore, 3βHSD1 is not known to be phosphorylated. Methods: Mass spectrometry was used to identify protein phosphorylation sites and steroid metabolites, genetic and pharmacologic methods were used to identify the kinase required for 3βHSD1 phosphorylation and mouse xenograft studies were performed with BMX inhibition. The identified mechanism was used to design and launch a multicenter phase 2 study of the BMX inhibitor abivertinib in combination with abiraterone in men with metastatic CRPC. Results: 3βHSD1 enzyme activity requires tyrosine phosphorylation at Y344 by the BMX kinase. Androgen biosynthesis is blocked by a phosphorylation-defective 3βHSD1 344F, or BMX genetic knockdown, or BMX pharmacologic inhibition. BMX inhibition using zanubrutinib suppresses CRPC growth in the C4-2 and VCaP xenograft models by blocking intratumoral androgen synthesis and tumor androgen receptor (AR) signaling. Discovery of this mechanism provides the rationale for the phase 2 Maverick trial of abivertinib, a BMX inhibitor, combined with abiraterone, in men with CRPC with adrenal-permissive HSD3B1 allele inheritance (NCT05361915). Eligibility includes 1) presence of metastatic CRPC, 2) measurable and/or non-measurable disease, and 3) confirmed positivity of adrenal-permissive HSD3B1(1245C) allele inheritance via central testing (cap heterozygosity at 50%). Patients will be enrolled in 2 arms: 1) abiraterone naïve (n=45) and 2) abiraterone progressing (n=55). All patients will receive treatment with abivertinib 200mg twice daily with abiraterone 1000mg daily and prednisone 5mg by mouth twice daily. The primary outcome is 6-month radiographic progression-free survival. On-treatment biopsies will be used to inform mechanisms of response and resistance in patients. Conclusions: BMX is required for 3βHSD1 phosphorylation, androgen biosynthesis and CRPC progression with the adrenal-permissive HSD3B1(1245C) allele. The Maverick trial will test clinical proof-of-concept of BMX inhibition in men with adrenal-permissive HSD3B1(1245C) inheritance. Clinical trial information: NCT05361915 .

The natural progression of patients with an IsoPSA value and its predictive ability of clinically significant prostate cancer on biopsy

325

Background: IsoPSA is a structure-based serum assay exploring the spectrum of possible prostate-specific antigen (PSA) isoforms. It was shown to outperform total and percent-free PSA in detecting clinically significant prostate cancer (csPCa) (grade group (GG) ≥2 on biopsy). IsoPSA reduced unnecessary biopsies and magnetic resonance imaging (MRI). We sought to compare the outcomes of eventual biopsy and imaging of surveilled patients with an initially normal or high IsoPSA, thus assessing IsoPSA’s prospective predictive ability of csPCa. Methods: We performed a single-center retrospective review of patients who underwent IsoPSA testing from 2017-present. Data was dichotomized into patients with normal (≤6) and high IsoPSA (>6). We collected the outcomes of any consequent IsoPSA and PSA test, prostate biopsy and MRI. We calculated the statistical IsoPSA’s characteristics for the prediction of csPCa on biopsy. Results: The median follow-up time of 811 patients who underwent IsoPSA testing was 18 months (IQR, 16.5-20). Among 443 patients with initial low IsoPSA, 5 (1.1%) had a csPCa on a subsequent biopsy, 19 (4.3%) subsequent high IsoPSA, 122 (27.5%) rising PSA, and 22 (5%) csPCa on MRI. Among 368 patients with initial high IsoPSA, 105 (28.5%) had a csPCa on a subsequent biopsy and 106 (28.8%) on an MRI. The sensitivity of IsoPSA to predict csPCa was 95.5%, and the NPV was 94.8%. Among 124 patients with high IsoPSA and initial negative biopsy, 110 had a subsequent negative and 14 a positive biopsy (10GG1 (8.1%), 4 ≥GG2 (3.2%)), with a respective median IsoPSA of 7.2 and 9.6 (p=0.007). An IsoPSA>10 generated an OR of csPCa of 7.2 (95%CI 2.1-25.2, p=0.0005). Conclusions: In 18-month follow-up, 1.1% of patients with normal IsoPSA developed csPCa compared to 28.5% of patients with high IsoPSA. In the cohort of patients with high IsoPSA and initially negative biopsy, 3.2% eventually developed csPCa, however, having a significantly higher IsoPSA than those who remained negative. The odds of having csPCa were 7 times higher with IsoPSA>10. [Table: see text]

IsoPSA Performance Characteristics are Unaffected by 5-Alpha Reductase Inhibitors or Alpha-Blockers: Results From the IsoPSA Validation Study

OBJECTIVE

To. determine the impact of 5-α reductase inhibitors or α-blockers on IsoPSA performance for the detection of actionable prostate cancer.

MATERIALS AND METHODS

This is a secondary analysis of data from an institutional review board approved, prospective, multicenter(8-sites) study evaluating IsoPSA in men ≥ 50 years of age with a total PSA ≥ 4 ng/mL with planned prostate biopsy who met previously described inclusion and exclusion criteria. Analytic groups included (i)all subjects, (ii-iii)+/- 5-ARI use, (iv-v)+/- α-blocker use. The performance characteristics of IsoPSA in these groups were assessed by ROC curve, sensitivity, and specificity (SP) analysis.

RESULTS

A total of 1385 men were recruited with 888 men included in final analysis. Actionable prostate cancer, defined as GG2+, was identified in a total of 316 patients with 40 and 217 patients reporting 5-ARI and α-blocker use respectively. Sensitivity to detect both prostate cancer and actionable cancer was similar between patient subsets (P >.05). SP was similar between patients regardless of 5-ARI(P >.05). Increased SP was noted in patients on α-blockers(GG1+: No-α-blocker: 0.360 vs α-blocker: 0.529, P <.05; GG2+: No-α-blocker: 0.40 vs α-blocker: 0.61, P <.05). ROC analysis demonstrates that IsoPSA performance is unaffected by 5-ARI or α-blocker use for prostate cancer and actionable cancer (GG2+) detection.

CONCLUSION

The performance of IsoPSA for detecting any prostate cancer and clinically actionable prostate cancer is unaffected by commonly used medications (5-ARI and α-blockers) for symptoms of benign prostatic hyperplasia.

Impact of Prostate Urethral Lift Device on Prostate Magnetic Resonance Image Quality

PURPOSE

Prostatic urethral lift with UroLift is a minimally invasive approach to treat symptomatic benign prostatic hypertrophy. This device causes artifacts on prostate magnetic resonance images. Our aim was to evaluate the impact of artifact on prostate magnetic resonance image quality.

MATERIALS AND METHODS

This was a single-center retrospective review of patients with UroLift who subsequently had prostate magnetic resonance imaging. Two readers graded UroLift artifact on each pulse sequence using a 5-point scale (1-nondiagnostic; 5-no artifact). Prostate Imaging Quality scores were assigned for the whole data set. The volume of gland obscured by artifact was measured. Linear and logistic regression models were used to identify predictors of poor image quality.

RESULTS

Thirty-seven patients were included. Poor image quality occurs more in the transition zone than the peripheral zone (15% vs 3%), at base/mid regions vs the apex (13%, 9%, and 5%, respectively) and on diffusion-weighted images vs T2-weighted and dynamic contrast-enhanced sequences (27%, 0.3%, 0%, respectively; P < .001). Suboptimal image quality (ie, Prostate Imaging Quality score <2) was found in 16%-24% of exams. The percentage of gland obscured by the UroLift artifact was higher on diffusion-weighted images and dynamic contrast-enhanced sequences than T2-weighted (32%, 9%, and 6%, respectively; P < .001).

CONCLUSIONS

UroLift artifact negatively affects prostate magnetic resonance image quality with greater impact in the mid-basal transition zone, obscuring a third of the gland on diffusion-weighted images. Patients considering this procedure should be counseled on the impact of this device on image quality and its potential implications for any image-guided prostate cancer workup.

Evaluation of cell-free DNA approaches for multi-cancer early detection

In the Circulating Cell-free Genome Atlas (NCT02889978) substudy 1, we evaluate several approaches for a circulating cell-free DNA (cfDNA)-based multi-cancer early detection (MCED) test by defining clinical limit of detection (LOD) based on circulating tumor allele fraction (cTAF), enabling performance comparisons. Among 10 machine-learning classifiers trained on the same samples and independently validated, when evaluated at 98% specificity, those using whole-genome (WG) methylation, single nucleotide variants with paired white blood cell background removal, and combined scores from classifiers evaluated in this study show the highest cancer signal detection sensitivities. Compared with clinical stage and tumor type, cTAF is a more significant predictor of classifier performance and may more closely reflect tumor biology. Clinical LODs mirror relative sensitivities for all approaches. The WG methylation feature best predicts cancer signal origin. WG methylation is the most promising technology for MCED and informs development of a targeted methylation MCED test.

Transcriptomic Features of Cribriform and Intraductal Carcinoma of the Prostate

BACKGROUND

Cribriform (CF) and/or intraductal carcinoma (IDC) are associated with more aggressive prostate cancer (CaP) and worse outcomes.

OBJECTIVE

The transcriptomic features that typify CF/IDC are not well described and the capacity for clinically utilized genomic classifiers to improve risk modeling for CF/IDC remains undefined.

DESIGN, SETTING, AND PARTICIPANTS

We performed a retrospective review of CaP patients who had Decipher testing at a single high-volume institution. Index lesions from radical prostatectomy specimens were identified by genitourinary pathologists who simultaneously reviewed prostatectomy specimens for the presence of CF and IDC features. Patients were grouped based on pathologic features, specifically the absence of CF/IDC (CF-/IDC-), CF positive only (CF+/IDC-), and CF/IDC positive (CF+/IDC+).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Clinical, pathologic, and genomic categorical variables were assessed using the Pearson chi-square test, while quantitative variables were assessed with the Kruskal-Wallis test. Multivariable logistic regression was used to identify the predictors of high-risk Decipher scores (>0.60). A gene set enrichment analysis was performed to identify genes and gene networks associated with CF/IDC status.

RESULTS AND LIMITATIONS

A total of 463 patients were included. Patients who were CF+/IDC+ had the highest Decipher risk scores (CF+/IDC+: 0.79 vs CF+/IDC-: 0.71 vs CF-/IDC-: 0.56, p < 0.001). On multivariate logistic regression, predictors of high-risk Decipher scores included the presence of CF, both alone (CF+/IDC-; odds ratio [OR]: 5.45, p < 0.001) or in combination with positive IDC status (CF+/IDC+; OR: 6.87, p < 0.001). On the gene set enrichment analysis, MYC pathway upregulation was significantly enriched in tumor samples from CF/IDC-positive patients (normalized enrichment score [NES]: 1.65, p = 0.046). Other enriched pathways included E2F targets (NES: 1.69, p = 0.031) and oxidative phosphorylation (NES: 1.68, =0 .033).

CONCLUSIONS

This is the largest series identifying an association between a clinically validated genomic classifier and the presence of CF and IDC at radical prostatectomy. Tumors with CF and intraductal features were associated with aggressive transcriptomic signatures.

PATIENT SUMMARY

Genomic-based tests are becoming readily available for the management of prostate cancer. We observed that Decipher, a commonly used genomic test in prostate cancer, correlates with unfavorable features in tissue specimens.

Detection of clinically significant index prostate cancer using micro-ultrasound: correlation with radical prostatectomy

OBJECTIVE

To determine the detection of clinically significant prostate cancer (csPCa) index lesion using high resolution transrectal micro-ultrasound (MicroUS) applying PRI-MUS (Prostate Risk Identification using Micro Ultrasound) score v1.0.

METHODS

Men who underwent radical prostatectomy following biopsy and MicroUS assessment were included. MicroUS dynamic cine loops of these patients were retrospectively reviewed by an experienced radiologist. The radiologist was aware that patients had undergone radical prostatectomy but was blinded to pathological data. Suspicious sites were assigned a PRI-MUS score. Radical prostatectomy specimens were examined with quarter mount technique. Detection rate of csPCa index lesion [Grade Group (GG) ≥2] by MicroUS was assessed at a patient level.

RESULTS

Twenty-five participants were included in the analysis. The median age was 65.5 years (range 56 - 74). Median PSA was 6.45 ng/dL (range 2 - 31.72). Two of 25 patients did not have csPCa (GG1 disease) on radical prostatectomy. MicroUS visualized 20/23 (87%) of the csPCa index lesions [median length 9 mm (range 1.5- 28.5)]. All identified lesions were categorized PRIMUS score 4 or 5. The 3 missed index lesions were in the transition zone [median length 10.5 mm (range 4.5-22.5)]. MicroUS missed 11 non index csPCa in 9 participants [median length 1.5 mm (range 1.5-10.5)]. Of these, 8 were GG2, two GG3 and one GG5. MicroUS identified the csPCa index lesion in all 9 of these men.

CONCLUSION

MicroUS showed high sensitivity (87%) in detecting index lesions in the prostate gland and identified 100% of index lesions in the peripheral zone.

Comparing Pathologic and Survival Outcomes Between Primary and Secondary Muscle Invasive Bladder Cancer when treated by Radical Cystectomy With or Without Neoadjuvant Chemotherapy

OBJECTIVE

To compare pathologic and survival outcomes between primary muscle invasive (pMIBC) and secondary muscle invasive (sMIBC) bladder cancer patients who were treated with or without cisplatin-based neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC).

METHODS

We reviewed cT2-T4/N0 MIBC patients at our institution between 2010-2019. pMIBC was defined as presenting with > cT2 disease on initial or restaging TURBT with no prior history of bladder cancer. sMIBC was defined as prior history of NMIBC that was treated with at least one induction course of BCG that progressed to MIBC. Outcomes analyzed included pathologic downstaging rates defined as <pT2/N0, pathologic complete response rates (pT0/N0), and survival outcomes (RFS, CSS, OS). Survival outcomes were analyzed using the Kaplan-Meier Method or Gray's test with log rank. Cox Proportional Hazards and semiparametric hazards models proposed by Fine and Gray were constructed to identify predictors of oncologic outcomes.

RESULTS

333 patients were included in the analysis (sMIBC: 48 vs pMIBC: 285). There were no differences in pathologic downstaging (sMIBC: 54% vs. pMIBC: 51%, p=0.67) or pathologic complete response (sMIBC: 33% vs. pMIBC: 28, p=0.46). Survival analysis showed no differences when patients were treated with NAC+RC in oncologic outcomes. On regression analysis, only >pT2 and N+ disease were predictors of poorer CSS and OS. Separate analysis of sMIBC patients whom underwent RC only (N=61), demonstrated inferior oncologic outcomes to other cohorts (p<0.01).

CONCLUSION

There were no differences in pathologic response or survival between pMIBC and sMIBC patients when managed with NAC and RC.

Coupling gamified continuing education with confidence-based assessment to address knowledge gaps and assess attitudes towards liquid biopsy for cancer screening among primary care providers

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Background: Blood-based liquid biopsy assays offer a simplified approach to detect cancer early, guide clinical decision making, and predict treatment success. Given their novelty, primary care providers need education to improve knowledge and confidence regarding their use. The use of gamification in continuing medical education (CME) has been shown to increase engagement and knowledge transfer, and confidence-based learning can improve the educational experience by identified areas in which learners lack comfort. Methods: We provided a gamified CME activity based on the principles of confidence-based learning designed to educate primary care providers (PCPs) on the latest advances regarding the use of liquid biopsy for cancer screening. The game coupled knowledge questions with self-assessment of confidence to gage awareness of these topics. Pre- and post-test was used to quantify the impact of the education. The CE activity was available for credit from March 31, 2021 to March 31, 2022. Results: As of January 2022, 389 PCPs have participated. Overall, participants scored an average 76% on gaming questions related to the rationale behind the use of cell free DNA (cfDNA) for cancer screening and the benefits of liquid biopsy over tissue biopsy, demonstrating relatively high baseline knowledge on these topics. Self-reported confidence among those who answered correctly, however, was only 3.4 out of 5.0, suggesting a lack of comfort with the concepts despite answering correctly. On topics related to specific studies that demonstrated the clinical utility of liquid biopsy, participants scored only 59% and confidence scored averaged 3.17 out of 5.0, demonstrating a lack of knowledge and comfort on these topics. Across all topics, providers scored a 61% on a pre-test. Post-learning, providers scored 89%, highlighting the impact of the education on knowledge gaps. Moreover, while 52% of participants had never ordered a liquid biopsy for cancer screening prior to the education, 69% report being likely or extremely likely to do so because of the education provided. Conclusions: Integration of gamified and confidence-based learning into CE activities is an impactful way to identify and address knowledge gaps while also informing the need for future education. In this study, while self-report of confidence generally correlated with knowledge scores, confidence scores were only average even among those who answered correctly, demonstrating the need for skills-based learning that may improve comfort with liquid biopsy in the clinical setting.

Caulobacter lipid A is conditionally dispensable in the absence of fur and in the presence of anionic sphingolipids

Lipid A, the membrane-anchored portion of lipopolysaccharide (LPS), is an essential component of the outer membrane (OM) of nearly all Gram-negative bacteria. Here we identify regulatory and structural factors that together render lipid A nonessential in Caulobacter crescentus. Mutations in the ferric uptake regulator fur allow Caulobacter to survive in the absence of either LpxC, which catalyzes an early step of lipid A synthesis, or CtpA, a tyrosine phosphatase homolog we find is needed for wild-type lipid A structure and abundance. Alterations in Fur-regulated processes, rather than iron status per se, underlie the ability to survive when lipid A synthesis is blocked. Fitness of lipid A-deficient Caulobacter requires an anionic sphingolipid, ceramide phosphoglycerate (CPG), which also mediates sensitivity to the antibiotic colistin. Our results demonstrate that, in an altered regulatory landscape, anionic sphingolipids can support the integrity of a lipid A-deficient OM.

Lipid A, the membrane-anchoring segment of lipopolysaccharide, is generally considered to be an essential component of the Gram-negative bacterial outer membrane. Zik et al. show that deletion of the transcriptional regulator fur and synthesis of the anionic sphingolipid ceramide phosphoglycerate enable Caulobacter crescentus to survive without lipid A.

The Promise of Multicancer Early Detection. Comment on Pons-Belda et al. Can Circulating Tumor DNA Support a Successful Screening Test for Early Cancer Detection? The Grail Paradigm. Diagnostics 2021, 11, 2171

Multicancer Early Detection (MCED) represents a new and exciting paradigm for the early detection of cancer, which is the leading cause of death worldwide. Current screening tests, recommended for only five cancer types (breast, lung, colon, cervical, and prostate), are limited by a lack of complete adherence to guideline-based use and by the fact that they have cumulative high false positive rates. MCED tests agnostically detect cancer signals in the blood with good sensitivity and low false positive rates, can predict the cancer site of origin with high accuracy, can detect highly lethal cancers that have no current screening tests, and promise to improve cancer screening by improving efficiency and reducing the overall number needed to screen. Herein we outline this promise and clarify several published misconceptions about this field.

IsoPSA® Reduces Provider Recommendations for Biopsy and Magnetic Resonance Imaging in Men with Total Prostate Specific Antigen ≥4 ng/ml: A Real-World Observational Clinical Utility Study

INTRODUCTION

We assessed the impact of the IsoPSA® test for prostate cancer risk assessment on provider patient management decisions in a real-world clinical setting.

METHODS

A total of 38 providers, including advanced practice providers, fellowship trained oncologists and general urologists in the Cleveland Clinic health system including both community-based practices and academic locations, enrolled 900 men being evaluated for prostate cancer; 734 met inclusion criteria (age ≥50 years, total serum prostate specific antigen [PSA] ≥4 and <100 ng/ml and no history of prostate cancer) and IsoPSA indication for use. A standard template was used to document biopsy recommendation prior to and after receiving IsoPSA results. The primary outcome was the number of biopsy and magnetic resonance imaging recommendation changes occurring after IsoPSA testing.

RESULTS

IsoPSA testing resulted in a 55% (284 vs 638) net reduction in recommendations for prostate biopsy for men with total PSA ≥4 ng/ml. Additionally, a 9% reduction in recommendations for magnetic resonance imaging was observed. There was strong concordance between IsoPSA results and provider recommendations for prostate biopsy, with 87% of patients with an IsoPSA index above the threshold recommended for biopsy and 92% of patients with an IsoPSA index below the threshold not recommended for biopsy.

CONCLUSIONS

In a real-world clinical setting, providers from diverse training backgrounds and practice settings readily adopted IsoPSA with substantial reductions in the rate of recommended prostate biopsies in patients with elevated PSA values (≥4 ng/ml). There was a high concordance between recommendation for or against prostate biopsy and the IsoPSA result.

Convergent evolution of bacterial ceramide synthesis

The bacterial domain produces numerous types of sphingolipids with various physiological functions. In the human microbiome, commensal and pathogenic bacteria use these lipids to modulate the host inflammatory system. Despite their growing importance, their biosynthetic pathway remains undefined since several key eukaryotic ceramide synthesis enzymes have no bacterial homolog. Here we used genomic and biochemical approaches to identify six proteins comprising the complete pathway for bacterial ceramide synthesis. Bioinformatic analyses revealed the widespread potential for bacterial ceramide synthesis leading to our discovery of a Gram-positive species that produces ceramides. Biochemical evidence demonstrated that the bacterial pathway operates in a different order from that in eukaryotes. Furthermore, phylogenetic analyses support the hypothesis that the bacterial and eukaryotic ceramide pathways evolved independently.

Pathologic and radiographic outcomes following prostate cancer diagnosis aided by IsoPSA testing

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Background: IsoPSA is a structure-based assay previously demonstrated to outperform prostate specific antigen (PSA) and free-to-total PSA ratio in detecting clinically significant prostate cancer at the time of biopsy (Stovsky, Klein 2019). Herein we report pathologic outcomes in patients treated via radical prostatectomy (RP) whom had undergone IsoPSA testing prior to their diagnostic biopsy. We also explore IsoPSA status in the context of MRI dependent findings, including PIRADS scores and PSA density. Methods: We conducted a retrospective review of patients whom had undergone IsoPSA testing prior to biopsy and RP at our institution between 2019-2021. We also identified subsets of patients with pre-operative prostate MRI’s. Exploratory analyses were performed to determine associations between IsoPSA and adverse histologic (cribiform, intraductal status (CB/ID), grade group status) pathologic (extraprostatic extension, seminal vesicle involvement, surgical margins) and radiographic (PSA density, PIRADS, location) features. We examined these data points in a randomly selected control group of RP patients whom had not had IsoPSA testing. Student’s T-test, Mann Whitney U, Kruskal Wallis, were used where appropriate. Results: A total of 83 patients underwent RP following IsoPSA testing, with 72.2% (60/83) also undergoing pre-operative prostate MRI. The mean total PSA was 10.3 ng/dL, IsoPSA index was 10.2 and prostate size 46.8 cc. IsoPSA was significantly associated with PSA density (median IsoPSA of 9.9 vs 7.8 for PSA density > 0.15, <0.15 respectively, p < 0.001). The median IsoPSA index was higher when the dominant tumor was found in the transitional zone versus peripheral zone (12.7 vs 8.8 p = 0.011). IsoPSA trended towards but was not associated with PIRADS-v2 score (1-2 vs 3 vs 4-5) (p = 0.1). IsoPSA was not selectively associated with adverse pathological or histological features. Conclusions: IsoPSA has been shown to predict clinically significant disease on biopsy, and as such may improve the selection of men for such intervention. In our initial cohort, IsoPSA reliably identified patients with clinically significant disease without selecting for unique adverse pathologic/histologic features when compared to a control group. Radiographically, IsoPSA was significantly associated with elevated PSA density ( > 0.15), tumor location (TZ vs PZ), and trended towards significance with PIRADS v.2 score (p = 0.1. Further work is encouraged to explore its adjunctive benefit in correlation to MRI features.

A genomic classifier for prostate cancer correlates with adverse pathologic features: Transcriptomic features of cribriform and intraductal carcinoma of the prostate

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Background: Invasive cribriform and intraductal carcinoma (CF/IDC) portends an unfavorable prognosis for patients diagnosed with prostate cancer (CaP). Limited studies with small sample sizes have explored whether genomic classifiers are associated with IDC and/or CF status. We investigated the correlation between Decipher genomic risk score and IDC/CF status and assessed PCa transcriptomic features. Methods: We performed a retrospective review of CaP patients who had Decipher testing at a single high volume center between 2009-2020. The highest grade index lesion from radical prostatectomy specimens was identified by GU pathologists and used for Decipher testing. Genitourinary pathologists reviewed prostatectomy specimens for the presence of CF and IDC features. Patients were divided into three groups based on pathologic features, absent CF/IDC (CF-/IDC-), CF positive only (CF+/IDC-), and CF/IDC positive (CF+/IDC+). Categorical clinical, genomic, and pathologic variables were assessed using the Pearson Chi-Square test, quantitative with the Kruskal-Wallis test. Multivariable logistic regression was used to identify predictors of high-risk Decipher GC scores. The Kaplan-Meier method with log-rank was used to compare biochemical recurrence free survival. Differential gene expression and gene network analysis was used to identify genes and pathways associated with IDC/CF features. Results: 463 patients were included with a median follow-up of 25 months. Patients who were CF+/IDC+ had higher GC scores (CF+/IDC+: 0.77 vs. CF+/IDC-: 0.71 vs. CF-/IDC-: 0.61, p<0.001). Patients who were CF+/IDC+ had a higher percentage of Gleason grade group >3 (CF+/IDC+: 79% vs. CF+/IDC-: 52% vs. CF-/IDC-: 52%, p<0.001). On multivariate logistic regression, predictors of high-risk GC score were presence of CF+/IDC+ features on final pathology (OR: 3.94, p<0.001) and pathologic Gleason grade group >3 (OR: 1.58, p=0.04). Transcriptomic analysis revealed that the hallmark androgen response pathway was significantly upregulated in CF+/IDC+ patients (Log fold change: 15.7, p<0001). Conclusions: This is the largest series investigating the association of a clinically validated genomic classifier and pathologic features such as cribriform and intraductal carcinoma. These findings have implications for the use of genomic classifiers in settings where expert GU pathology is not readily available and in potentially unmasking adverse histology at the time of biopsy.[Table: see text]

Do prostate MRI reports consider focal therapy when describing diagnostic findings? A descriptive review and analysis of concordance among prostate MRI reports and radical prostatectomy pathology reports

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Background: Focal therapy (FT) for prostate cancer (PCa) is becoming an attractive option for men seeking treatments that minimize the morbidity of whole gland therapy. Prostate MRI reports should include lesion location, presence of bilateral extension and presence of multifocality as these radiographic features are essential in selecting appropriate candidacy. We aim to evaluate concordance of disease between MRI and final pathology reports. Methods: We conducted a retrospective review of pathology reports from radical prostatectomies (RP) performed at our institution between 2016-2019, in patients whom also underwent pre-operative prostate MRI’s. The number and locations of PI-RADS ≥ 3 lesions described in MRI reports were compared against the RP findings and assessed for disease concordance in terms of lesion location, extent (unilateral vs. bilateral extent) and/or the presence of tumor multifocality. Fischer’s exact test was used for statistical analysis. Results: A total of 1593 patients underwent RP, among which 416 (26.1%) had preoperative prostate MRI’s. A majority (65.3%) (n = 273/416) of MRI’s reported a single PI-RADS > 3 lesion, 51/416 (12.3%) had negative MRI’s and 22.1% (92/416) described >2 PI-RADS ≥ 3 lesions. A total of n = 388/416 (93.2%) had detailed descriptions of their MRI and path reports for comparative analysis. MRI and final path tumor concordance with respect to unifocal extent or multifocality was low at 37.2%. When a single PI-RADS > 3 lesion was described, concordance with final path was 37.6% as compared to 55.6% when >2 lesions were described (p = 0.006). Discordant findings at final path included the presence of tumor multifocality (80.7%) or the extent of a unifocal lesion (19.3%). Lesions crossing the midline were uncommonly reported on MRI (16%). When prostate midline assessment was included in the evaluation of lesion extent, the degree of concordance with final pathology improved from 33.3% to 64.2% (p = 0.038). Conclusions: Prostate MRI reports have a large discordance with RP reports. Tumor multifocality and/or unifocal disease crossing the midline may not hold significant meaning if the disease is ultimately organ confined and the treatment is aimed at the whole gland. However, in the context of focal therapy, these findings are of germane importance. Radiologists are encouraged to consider focal therapy as a treatment strategy when describing MRI findings and acknowledge the importance of tumor multifocality/bilaterality in this context.

Genetic Factors Associated with Prostate Cancer Conversion from Active Surveillance to Treatment

Men diagnosed with low-risk prostate cancer (PC) are increasingly electing active surveillance (AS) as their initial management strategy. While this may reduce the side effects of treatment for prostate cancer, many men on AS eventually convert to active treatment. PC is one of the most heritable cancers, and genetic factors that predispose to aggressive tumors may help distinguish men who are more likely to discontinue AS. To investigate this, we undertook a multi-institutional genome-wide association study (GWAS) of 5,222 PC patients and 1,139 other patients from replication cohorts, all of whom initially elected AS and were followed over time for the potential outcome of conversion from AS to active treatment. In the GWAS we detected 18 variants associated with conversion, 15 of which were not previously associated with PC risk. With a transcriptome-wide association study (TWAS), we found two genes associated with conversion (MAST3, p = 6.9×10-7 and GAB2, p = 2.0×10-6). Moreover, increasing values of a previously validated 269-variant genetic risk score (GRS) for PC was positively associated with conversion (e.g., comparing the highest to the two middle deciles gave a hazard ratio [HR] = 1.13; 95% Confidence Interval [CI]= 0.94-1.36); whereas, decreasing values of a 36-variant GRS for prostate-specific antigen (PSA) levels were positively associated with conversion (e.g., comparing the lowest to the two middle deciles gave a HR = 1.25; 95% CI, 1.04-1.50). These results suggest that germline genetics may help inform and individualize the decision of AS-or the intensity of monitoring on AS-versus treatment for the initial management of patients with low-risk PC.

A Rare Germline HOXB13 Variant Contributes to Risk of Prostate Cancer in Men of African Ancestry

A rare African ancestry-specific germline deletion variant in HOXB13 (X285K, rs77179853) was recently reported in Martinican men with early-onset prostate cancer. Given the role of HOXB13 germline variation in prostate cancer, we investigated the association between HOXB13 X285K and prostate cancer risk in a large sample of 22 361 African ancestry men, including 11 688 prostate cancer cases. The risk allele was present only in men of West African ancestry, with an allele frequency in men that ranged from 0.40% in Ghana and 0.31% in Nigeria to 0% in Uganda and South Africa, with a range of frequencies in men with admixed African ancestry from North America and Europe (0-0.26%). HOXB13 X285K was associated with 2.4-fold increased odds of prostate cancer (95% confidence interval [CI] = 1.5-3.9, p = 2 × 10^-4), with greater risk observed for more aggressive and advanced disease (Gleason ≥8: odds ratio [OR] = 4.7, 95% CI = 2.3-9.5, p = 2 × 10^-5; stage T3/T4: OR = 4.5, 95% CI = 2.0-10.0, p = 2 × 10^-4; metastatic disease: OR = 5.1, 95% CI = 1.9-13.7, p = 0.001). We estimated that the allele arose in West Africa 1500-4600 yr ago. Further analysis is needed to understand how the HOXB13 X285K variant impacts the HOXB13 protein and function in the prostate. Understanding who carries this mutation may inform prostate cancer screening in men of West African ancestry. PATIENT SUMMARY: A rare African ancestry-specific germline deletion in HOXB13, found only in men of West African ancestry, was reported to be associated with an increased risk of overall and advanced prostate cancer. Understanding who carries this mutation may help inform screening for prostate cancer in men of West African ancestry.

Prospective Multicenter Comparison of Open and Robotic Radical Prostatectomy: The PROST-QA/RP2 Consortium

PURPOSE

Our goal was to evaluate the comparative effectiveness of robot-assisted laparoscopic prostatectomy (RALP) and open radical prostatectomy (ORP) in a multicenter study.

MATERIALS AND METHODS

We evaluated men with localized prostate cancer at 11 high-volume academic medical centers in the United States from the PROST-QA (2003-2006) and the PROST-QA/RP2 cohorts (2010-2013) with a pre-specified goal of comparing RALP (549) and ORP (545). We measured longitudinal patient-reported health-related quality of life (HRQOL) at pre-treatment and at 2, 6, 12, and 24 months, and pathological and perioperative outcomes/complications.

RESULTS

Demographics, cancer characteristics, and margin status were similar between surgical approaches. ORP subjects were more likely to undergo lymphadenectomy (89% vs 47%; p <0.01) and nerve sparing (94% vs 89%; p <0.01). RALP vs ORP subjects experienced less mean intraoperative blood loss (192 vs 805 mL; p <0.01), shorter mean hospital stay (1.6 vs 2.1 days; p <0.01), and fewer blood transfusions (1% vs 4%; p <0.01), wound infections (2% vs 4%; p=0.02), other infections (1% vs 4%; p <0.01), deep venous thromboses (0.5% vs 2%; p=0.04), and bladder neck contractures requiring dilation (1.6% vs 8.3%; p <0.01). RALP subjects reported less pain (p=0.04), less activity interference (p <0.01) and higher incision satisfaction (p <0.01). Surgical approach (RALP vs ORP) was not a significant predictor of longitudinal HRQOL change in any HRQOL domain.

CONCLUSIONS

In high-volume academic centers, RALP and ORP patients may expect similar long-term HRQOL outcomes. Overall, RALP patients have less pain, shorter hospital stays, and fewer post-surgical complications such as blood transfusions, infections, deep venous thromboses, and bladder neck contractures.

Performance of a Prostate-Specific Membrane Antigen Positron Emission Tomography/Computed Tomography-Derived Risk-Stratification Tool for High-risk and Very High-risk Prostate Cancer

IMPORTANCE

Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) can detect low-volume, nonlocalized (ie, regional or metastatic) prostate cancer that was occult on conventional imaging. However, the long-term clinical implications of PSMA PET/CT upstaging remain unclear.

OBJECTIVES

To evaluate the prognostic significance of a nomogram that models an individual's risk of nonlocalized upstaging on PSMA PET/CT and to compare its performance with existing risk-stratification tools.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included patients diagnosed with high-risk or very high-risk prostate cancer (ie, prostate-specific antigen [PSA] level >20 ng/mL, Gleason score 8-10, and/or clinical stage T3-T4, without evidence of nodal or metastatic disease by conventional workup) from April 1995 to August 2018. This multinational study was conducted at 15 centers. Data were analyzed from December 2020 to March 2021.

EXPOSURES

Curative-intent radical prostatectomy (RP), external beam radiotherapy (EBRT), or EBRT plus brachytherapy (BT), with or without androgen deprivation therapy.

MAIN OUTCOMES AND MEASURES

PSMA upstage probability was calculated from a nomogram using the biopsy Gleason score, percentage positive systematic biopsy cores, clinical T category, and PSA level. Biochemical recurrence (BCR), distant metastasis (DM), prostate cancer-specific mortality (PCSM), and overall survival (OS) were analyzed using Fine-Gray and Cox regressions. Model performance was quantified with the concordance (C) index.

RESULTS

Of 5275 patients, the median (IQR) age was 66 (60-72) years; 2883 (55%) were treated with RP, 1669 (32%) with EBRT, and 723 (14%) with EBRT plus BT; median (IQR) PSA level was 10.5 (5.9-23.2) ng/mL; 3987 (76%) had Gleason grade 8 to 10 disease; and 750 (14%) had stage T3 to T4 disease. Median (IQR) follow-up was 5.1 (3.1-7.9) years; 1221 (23%) were followed up for at least 8 years. Overall, 1895 (36%) had BCR, 851 (16%) developed DM, and 242 (5%) died of prostate cancer. PSMA upstage probability was significantly prognostic of all clinical end points, with 8-year C indices of 0.63 (95% CI, 0.61-0.65) for BCR, 0.69 (95% CI, 0.66-0.71) for DM, 0.71 (95% CI, 0.67-0.75) for PCSM, and 0.60 (95% CI, 0.57-0.62) for PCSM (P < .001). The PSMA nomogram outperformed existing risk-stratification tools, except for similar performance to Staging Collaboration for Cancer of the Prostate (STAR-CAP) for PCSM (eg, DM: PSMA, 0.69 [95% CI, 0.66-0.71] vs STAR-CAP, 0.65 [95% CI, 0.62-0.68]; P < .001; Memorial Sloan Kettering Cancer Center nomogram, 0.57 [95% CI, 0.54-0.60]; P < .001; Cancer of the Prostate Risk Assessment groups, 0.53 [95% CI, 0.51-0.56]; P < .001). Results were validated in secondary cohorts from the Surveillance, Epidemiology, and End Results database and the National Cancer Database.

CONCLUSIONS AND RELEVANCE

These findings suggest that PSMA upstage probability is associated with long-term, clinically meaningful end points. Furthermore, PSMA upstaging had superior risk discrimination compared with existing tools. Formerly occult, PSMA PET/CT-detectable nonlocalized disease may be the main driver of outcomes in high-risk patients.

Validating the Association of Adverse Pathology with Distant Metastasis and Prostate Cancer Mortality 20-Years After Radical Prostatectomy

PURPOSE

To assess the association of adverse pathology (AP), defined as high-grade (≥ Gleason Grade Group 3) and/or non-organ confined disease, with long-term oncologic outcomes after radical prostatectomy (RP).

MATERIALS AND METHODS

Using a stratified cohort sampling design, we evaluated the association of AP with the risk of distant metastasis (DM) and prostate cancer-specific mortality (PCSM) up to 20 years after RP in 428 patients treated between 1987 to 2004. Cox regression of cause-specific hazards was used to estimate the absolute risk of both endpoints, with death from other causes treated as a competing risk. Additionally, subgroup analysis in patients with low and/or intermediate-risk disease, who are potentially eligible for active surveillance (AS), was performed.

RESULTS

Within the cohort sample, 53% of men exhibited AP at time of RP, with median follow up of 15.5 years (IQR 14.6-16.6 years) thereafter. Adverse pathology was highly associated with DM and PCSM in the overall cohort (HR 12.30, 95% confidence interval [CI] 5.30-28.55, and HR 10.03, 95% CI 3.42-29.47, respectively, both P < 0.001). Adverse pathology was also highly associated with DM and PCSM in the low/intermediate-risk subgroup (HR 10.48, 95% CI 4.18-26.28, and 8.60, 95% CI 2.40-30.48, respectively, both P < 0.001).

CONCLUSIONS

Adverse pathology at the time of RP is highly associated with future development of DM and PCSM. Accurate prediction of AP may thus be useful for individualizing risk-based surveillance and treatment strategies.

Influence of 5-Alpha Reductase Inhibitors on Prostate Cancer Detection with Magnetic Resonance Imaging: A Matched Cohort Study

PURPOSE

We evaluated the influence of 5-alpha reductase inhibitors (5-ARIs) on the performance of magnetic resonance imaging (MRI) for detection of Gleason grade group (GG) ≥2 prostate cancer, and on apparent diffusion coefficient (ADC) maps.

MATERIALS AND METHODS

This single center, retrospective study included men who had MRI for initial detection or active surveillance of prostate cancer. The study group included 59 men who used for 5-ARIs for ≥12 months, and the control group included 59 men who were matched for both MRI indication and biopsy results. DeLong's test was used to compare the area under the receiver operating characteristic curve (AUC) for detection of GG ≥2 cancer between the groups. Wilcoxon rank sum test was used for comparison of lesions apparent diffusion coefficient (ADC) metrics between the groups.

RESULTS

MRI accuracy in the study group (AUC=0.778) was not significantly different compared to the control group (AUC=0.821; 95% CI for difference 0.22-0.13; p=0.636). In the control group, all ADC metrics were lower in lesions with GG ≥2 cancer on biopsy than in those with GG 1 cancer or negative results (p=0.001-0.01). In the study group, this difference was significant only when the mean ADC of the lesions was normalized by the ADC of urine (p=0.044).

CONCLUSIONS

Long-term exposure to 5-ARIs does not seem to impair the detection of significant cancer on MRI but may affect the ability of ADC metrics to discriminate between lesions that harbor significant cancer and those that harbor insignificant cancer or benign tissue.

Gut Microbiome-Dependent Metabolic Pathways and Risk of Lethal Prostate Cancer: Prospective Analysis of a PLCO Cancer Screening Trial Cohort

BACKGROUND

Diet and the gut microbiome have a complex interaction that generates metabolites with an unclear effect on lethal prostate cancer risk. Identification of modifiable risk factors for lethal prostate cancer is challenging given the long natural history of this disease and difficulty of prospectively identifying lethal cancers.

METHODS

Mass spectrometry was performed on baseline serum samples collected from 173 lethal prostate cancer cases and 519 controls enrolled in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening trial. Baseline serum levels of choline, carnitine, betaine, γ-butyrobetaine, crotonobetaine, phenylacetylglutamine, hippuric acid, and p-cresol sulfate were quantified and analyzed by quartile. Conditional multivariable logistic regression analysis associated analyte levels with lethal prostate cancer incidence after adjusting for body mass index and PSA. The Cochran-Armitage test evaluated analyte level trends across quartiles.

RESULTS

Relative to those in the first quartile, cases with the highest baseline levels of choline (Q4 OR: 2.19; 95% CI, 1.23-3.90; P-trend: 0.005) and betaine (Q4 OR: 1.86; 95% CI, 1.05-3.30; P-trend: 0.11) exhibited increased odds of developing lethal prostate cancer. Higher baseline serum levels of phenylacetylglutamine (Q4 OR: 2.55; 95% CI, 1.40-4.64; P-trend: 0.003), a gut microbiome metabolite of phenylalanine with adrenergic activity, were also associated with lethal prostate cancer.

CONCLUSIONS

Baseline serum levels of one-carbon methyl donors and adrenergic compounds resulting from human and gut microbiota-mediated metabolism are associated with increased lethal prostate cancer risk.

IMPACT

Dietary composition, circulating metabolite levels, and downstream signaling pathways may represent modifiable risk factors associated with incident lethal prostate cancer. Beta-adrenergic blockade represents an additional target for oncologic risk reduction.

Prognostic Significance of Blood-Based Multi-cancer Detection in Plasma Cell-Free DNA

PURPOSE

We recently reported the development of a cell-free DNA (cfDNA) targeted methylation (TM)-based sequencing approach for a multi-cancer early detection (MCED) test that includes cancer signal origin prediction. Here, we evaluated the prognostic significance of cancer detection by the MCED test using longitudinal follow-up data.

EXPERIMENTAL DESIGN

As part of a Circulating Cell-free Genome Atlas (CCGA) substudy, plasma cfDNA samples were sequenced using a TM approach, and machine learning classifiers predicted cancer status and cancer signal origin. Overall survival (OS) of cancer participants in the first 3 years of follow-up was evaluated in relation to cancer detection by the MCED test and clinical characteristics.

RESULTS

Cancers not detected by the MCED test had significantly better OS (P < 0.0001) than cancers detected, even after accounting for other covariates, including clinical stage and method of clinical diagnosis (i.e., standard-of-care screening or clinical presentation with signs/symptoms). Additionally, cancers not detected by the MCED test had better OS than was expected when data were adjusted for age, stage, and cancer type from the Surveillance, Epidemiology, and End Results (SEER) program. In cancers with current screening options, the MCED test also differentiated more aggressive cancers from less aggressive cancers (P < 0.0001).

CONCLUSIONS

Cancer detection by the MCED test was prognostic beyond clinical stage and method of diagnosis. Cancers not detected by the MCED test had better prognosis than cancers detected and SEER-based expected survival. Cancer detection and prognosis may be linked by the underlying biological factor of tumor fraction in cfDNA.