Implementation of PSMA PET/CT and alignment of ordering to SNMMI appropriate use criteria in a large network system

INTRODUCTION

The Society of Nuclear Medicine and Molecular Imaging (SNMMI) provides appropriate use criteria (AUC) for prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) which include guidance on imaging in newly diagnosed prostate cancer and in patients with biochemically recurrent (BCR) disease. This study aims to examine trends in PSMA implementation and the prevalence and outcomes of scans ordered in scenarios deemed rarely appropriate or not meeting SNMMI AUC.

METHODS

We retrospectively identified patients who were diagnosed with presumptive National Comprehensive Cancer Network unfavorable intermediate, high, or very high risk prostate cancer, patients who underwent staging for BCR, and all patients staged with PSMA between July 2021 and March 2023. Positivity was validated by adherence to a predetermined reference standard.

RESULTS

The frequency of PSMA use increased in initial staging from 24% to 80% and work-up of BCR from 91% to 99% over our study period. In addition, 5% (17/340) of PSMA scans ordered for initial staging did not meet AUC and 3% (15/557) of posttreatment scans were deemed rarely appropriate. Initial staging orders not meeting SNMMI AUC resulted in no positivity (0/17), while rarely appropriate posttreatment scans were falsely positive in 75% (3/4) of cases. Urologists (53%, 17/32) comprised the largest ordering specialty in rarely appropriate use.

CONCLUSION

The frequency of PSMA use rose across the study period. A significant minority of patients received PSMA PET/CT in rarely appropriate scenarios yielding no positivity in initial staging and significant false positivity post-therapy. Further education of providers and electronic medical record-based interventions could help limit the rarely appropriate use of PET imaging.

The broad reach and inaccuracy of men's health information on social media: analysis of TikTok and Instagram

Social media (SoMe) offers great potential to expand access to health information, but a significant proportion of users consume its content instead of consulting a physician. We sought to quantify the volume and characterize the accuracy of men's health-related content on TikTok and Instagram. We searched TikTok and Instagram for the terms: testosterone, erectile dysfunction, male infertility, semen retention, Peyronie's disease, and vasectomy. The top 10 hashtags for each term were used to estimate the total impressions for each term on each platform, and posts were then characterized by creator type, content type, and accuracy (1 to 5 scale). TikTok had 2,312,407,100 impressions and Instagram had 3,107,300 posts across all topics. Semen retention had the most impressions on TikTok (1,216,074,000) and posts on Instagram (1,077,000). Physicians created only a small portion of total TikTok and Instagram posts (10.3% and 12.9%, respectively). Across all topics, the accuracy of content was poor (2.6 ± 1.7), however, physician posts were more accurate than non-physician posts (mean 4.2 ± 1.2 vs 2.3 ± 1.6, p < 0.001, respectively). Men's health content is popular on TikTok and Instagram but is not accurate. We recommend that physicians actively engage in SoMe to address misinformation.

Ultrasensitive PSA: rethinking post-surgical management for node positive prostate cancer

Introduction

Clinicians may offer patients with positive lymph nodes (pN1) and undetectable PSA following surgery for prostate cancer either observation or adjuvant therapy based on AUA, EAU, and NCCN guidelines considering standard PSA detection thresholds of <0.1ng/ml. Here we sought to investigate the outcomes of pN1 patients in the era of ultrasensitive PSA testing.

Methods

We queried the Northwestern Electronic Data Warehouse for patients with prostate cancer who were pN1 at radical prostatectomy and followed with ultrasensitive PSA. Patients receiving neoadjuvant treatment were excluded. We compared clinical characteristics including age, race, pre-operative PSA, Gleason grade, tumor stage, surgical margins, and nodal specimens to identify factors associated with achievement and maintenance of an undetectable PSA (defined as <0.01 ng/mL). Statistics were performed using t-test, Mann-Whitney U test, chi-squared analysis, and logistic regression with significance defined as p<0.05.

Results

From 2018-2023, 188 patients were included. Subsequently, 39 (20.7%) had a PSA decline to undetectable levels (<0.01 ng/mL) post-operatively at a median time of 63 days. Seven percent of these men (3/39) were treated with adjuvant RT + ADT with undetectable PSA levels. 13/39 (33.3%) had eventual rises in PSA to ≥0.01 ng/mL for which they underwent salvage RT with ADT. Overall, 23/39 (59%) patients achieved and maintained undetectable PSA levels without subsequent therapy at median follow-up of 24.2 mo. Compared to patients with PSA persistence after surgery or elevations to detectable levels (≥0.01 ng/mL), patients who achieved and maintained undetectable levels had lower Gleason grades (p=0.03), lower tumor stage (p<0.001), fewer positive margins (p=0.02), and fewer involved lymph nodes (p=0.02). On multivariable analysis, only primary tumor (pT) stage was associated with achieving and maintaining an undetectable PSA; pT3b disease was associated with a 6.6-fold increased chance of developing a detectable PSA (p=0.03).

Conclusion

Ultrasensitive PSA can aid initiation of early salvage therapy for lymph node positive patients after radical prostatectomy while avoiding overtreatment in a significant subset. 20% of patients achieved an undetectable PSA and over half of this subset remained undetectable after 2 years.

Optimizing detection of clinically significant prostate cancer through nomograms incorporating mri, clinical features, and advanced serum biomarkers in biopsy naïve men

PURPOSE

To develop nomograms that predict the detection of clinically significant prostate cancer (csPCa, defined as ≥GG2 [Grade Group 2]) at diagnostic biopsy based on multiparametric prostate MRI (mpMRI), serum biomarkers, and patient clinicodemographic features.

MATERIALS AND METHODS

Nomograms were developed from a cohort of biopsy-naïve men presenting to our 11-hospital system with prostate specific antigen (PSA) of 2-20 ng/mL who underwent pre-biopsy mpMRI from March 2018-June 2021 (n = 1494). The outcomes were the presence of csPCa and high-grade prostate cancer (defined as ≥GG3 prostate cancer). Using significant variables on multivariable logistic regression, individual nomograms were developed for men with total PSA, % free PSA, or prostate health index (PHI) when available. The nomograms were both internally validated and evaluated in an independent cohort of 366 men presenting to our hospital system from July 2021-February 2022.

RESULTS

1031 of 1494 men (69%) underwent biopsy after initial evaluation with mpMRI, 493 (47.8%) of whom were found to have ≥GG2 PCa, and 271 (26.3%) were found to have ≥GG3 PCa. Age, race, highest PIRADS score, prostate health index when available, % free PSA when available, and PSA density were significant predictors of ≥GG2 and ≥GG3 PCa on multivariable analysis and were used for nomogram generation. Accuracy of nomograms in both the training cohort and independent cohort were high, with areas under the curves (AUC) of ≥0.885 in the training cohort and ≥0.896 in the independent validation cohort. In our independent validation cohort, our model for ≥GG2 prostate cancer with PHI saved 39.1% of biopsies (143/366) while only missing 0.8% of csPCa (1/124) with a biopsy threshold of 20% probability of csPCa.

CONCLUSIONS

Here we developed nomograms combining serum testing and mpMRI to help clinicians risk stratify patients with elevated PSA of 2-20 ng/mL who are being considered for biopsy. Our nomograms are available at https://rossnm1.shinyapps.io/MynMRIskCalculator/ to aid with biopsy decisions.

Utilization of genetic testing in men with advanced prostate cancer

BACKGROUND

Genetic evaluation of men with advanced prostate cancer is recognized as imperative both to guide treatment decisions and to trigger cascade genetic testing of family members. Here we investigate utilization patterns of genetic testing among a contemporary cohort of men with advanced prostate cancer at our institution.

METHODS

We queried the Northwestern Electronic Data Warehouse from January 2021 to present for all men diagnosed with National Comprehensive Cancer Network high-risk/very high-risk, regional, or metastatic prostate cancer. Patients were excluded from analyses if treated at an outside institution and/or presented for a second opinion evaluation. Statistics were performed using t-test, Chi-squared test, and univariable and multivariable logistic regression with significance defined as p < 0.05.

RESULTS

Atotal of 320 men (52.5%) had local/regional disease and 290 (47.5%) had metastatic disease, 53 (18.3%) of whom had castrate resistant prostate cancer. Rates of germline genetic testing rate were low in patients with localized disease (9.4%) and metastatic disease (34.1%). Only 19 (35.8%) men diagnosed with metastatic castrate resistant prostate cancer underwent germline genetic evaluation. Germline testing was most frequently discussed or ordered by medical oncologists (52%) followed by urologists (20%). Men who underwent germline testing were younger (p < 0.001), more likely to have Medicaid or private insurance (p = 0.002), and more likely to have metastatic disease (p < 0.001). There were no statistically significant differences in baseline PSA, ethnicity, race, or castration sensitivity status. Age (odds ratio [OR]: 0.94, 95% confidence interval [CI]: 0.91-0.97, p < 0.001) and metastatic disease (OR: 5.71, 95% CI: 3.63-9.22, p < 0.001) were significant independent predictors of genetic testing on multivariable logistic regression.

CONCLUSIONS

Here we report that utilization of genetic testing is associated with metastatic disease and inversely associated with age. Overall, utilization rates of genetic testing remain low in all patient groups, including in the metastatic castrate resistant setting, where genetic testing can identify patients with homologous recombination repair deficiency who may benefit from use of targeted therapeutics such as PARP inhibitors. Genetic testing in men with aggressive prostate cancer is critical and barriers to routine implementation of testing require further study to develop strategies to improve utilization rates.

Real-world use of MRI for risk stratification prior to prostate biopsy

BACKGROUND

The utilization of MRI to risk stratify elevated PSA prior to prostate biopsy has been inconsistently adopted and varies considerably by practice setting. This study aims to evaluate the usage and performance of MRI as an advanced risk stratification tool of elevated PSA prior to biopsy and identify factors associated with differential utilization of MRI at a large academic setting with ready access to 3T multiparametric MRI of the prostate.

METHODS

A retrospective single-center study of 2900 men presenting with elevated PSA 2-20 ng/mL from 2018 through 2021 was conducted. We analyzed trends in MRI utilization and outcomes of prostate biopsy by MRI usage. Univariate and multivariate logistic regressions were performed to calculate odds ratios to identify patient- and provider-level predictors of MRI usage.

RESULTS

Rates of prebiopsy MRI utilization increased from 56% in 2018 to 89% in 2021 (p < 0.001). Prebiopsy MRI led to biopsy avoidance in 31% of men. MRI usage enhanced detection of clinically significant prostate cancer by 13% and reduced identification of Gleason Grade Group 1 disease by 3% and negative biopsies by 10% (p < 0.001). Men who received MRI were more likely to be younger than 75 years in age and have private or Medicare insurance, PSA >4 ng/mL, and PHI >27. In both univariate and multivariate analysis, black race and Medicaid insurance were associated with reduced MRI utilization (all p < 0.001). Urologic provider was an independent predictor of MRI usage (p < 0.001).

CONCLUSIONS

Use of MRI as a risk stratification tool for elevated PSA rose during this 4-year study period. Men who self-identify as black or men with Medicaid coverage have diminished rates of MRI usage. Considerable provider-level variability in MRI use was observed. Future research aimed at identifying factors affecting implementation of MRI as a routine risk assessment tool is warranted.

Biliary Anatomy

The hepatobiliary system is known to have high anatomic variability, as studies have shown variant rates of over 40% among individuals. This review will describe biliary anatomy and the most common anatomic variants, knowledge of which is critical to ensuring safe and effective biliary interventions.

Role of Interventional Radiology in the Management of Acute Cholangitis

Acute cholangitis presents with a wide severity spectrum and can rapidly deteriorate from local infection to multiorgan failure and fatal sepsis. The pathophysiology, diagnosis, and general management principles will be discussed in this review article. The focus of this article will be on the role of biliary drainage performed by interventional radiology to manage acute cholangitis. There are specific scenarios where percutaneous drainage should be preferred over endoscopic drainage. Percutaneous transhepatic and transjejunal biliary drainage are both options available to interventional radiology. Additionally, interventional radiology is now able to manage these patients beyond providing acute biliary drainage including cholangioplasty, stenting, and percutaneous cholangioscopy/biopsy.

Oxidatively stable nanoporous silicon photocathodes with enhanced onset voltage for photoelectrochemical proton reduction

Stable and high-performance nanoporous "black silicon" photoelectrodes with electrolessly deposited Pt nanoparticle (NP) catalysts are made with two metal-assisted etching steps. Doubly etched samples exhibit an ∼300 mV positive shift in photocurrent onset for photoelectrochemical proton reduction compared to oxide-free planar Si with identical catalysts. We find that the photocurrent onset voltage of black Si photocathodes prepared from single-crystal planar Si wafers by an Ag-assisted etching process increases in oxidative environments (e.g., aqueous electrolyte) owing to a positive flat-band potential shift caused by surface oxidation. However, within 24 h, the surface oxide layer becomes a kinetic barrier to interfacial charge transfer that inhibits proton reduction. To mitigate this issue, we developed a novel second Pt-assisted etch process that buries the Pt NPs deep into the nanoporous Si surface. This second etch shifts the onset voltage positively, from +0.25 V to +0.4 V versus reversible hydrogen electrode, and reduces the charge-transfer resistance with no performance decrease seen for at least two months. PEC performance was stable owing to Pt NP catalysts that were buried deeply in the photoelectrode by the second etch, below a thick surface layer comprised primarily of amorphous SiO2 along with some degree of remaining crystalline Si as observed by scanning and transmission electron micrographs. Electrochemical impedance studies reveal that the second etch leads to a considerably smaller interfacial charge-transfer resistance than samples without the additional etch, suggesting that burying the Pt NPs improves the interfacial contact to the crystalline silicon surface.

Interfacial ferromagnetism in LaNiO3/CaMnO3 superlattices

We observe interfacial ferromagnetism in superlattices of the paramagnetic metal LaNiO3 and the antiferromagnetic insulator CaMnO3. LaNiO3 exhibits a thickness dependent metal-insulator transition and we find the emergence of ferromagnetism to be coincident with the conducting state of LaNiO3. That is, only superlattices in which the LaNiO3 layers are metallic exhibit ferromagnetism. Using several magnetic probes, we have determined that the ferromagnetism arises in a single unit cell of CaMnO3 at the interface. Together these results suggest that ferromagnetism can be attributed to a double exchange interaction among Mn ions mediated by the adjacent itinerant metal.

Investigating the electronic structure of fluorite-structured oxide compounds: comparison of experimental EELS with first principles calculations

Energy loss spectra from fluorite-structured ZrO(2), CeO(2), and UO(2) compounds are compared with theoretical calculations based on density functional theory (DFT) and its extensions, including the use of Hubbard-U corrections (DFT + U) and hybrid functionals. Electron energy loss spectra (EELS) were obtained from each oxide using a scanning transmission electron microscope (STEM). The same spectra were computed within the framework of the full-potential linear augmented plane-wave (FLAPW) method. The theoretical and experimental EEL spectra are compared quantitatively using non-linear least squares peak fitting and a cross-correlation approach, with the best level of agreement between experiment and theory being obtained using the DFT + U and hybrid computational approaches.

Protective effect of Chresta martii extract against indomethacin-induced gastric lesions in mice

Chresta martii (Asteraceae) is a plant found in the Xingó region (semi-arid area) in Northeastearn Brazil, and is recognized by the local population as a traditional herb used to treat gastric diseases. This is the first report of the chemical composition, acute toxicity, and gastroprotective effect in mice of the hydroalcoholic extract (HAE) from the aerial parts (leaves and flowers) of Chresta martii. Animals received HAE doses from 10 to 2000 mg/kg, i.p. or 50 to 3000 mg/kg, p.o.) and were observed over 48 h for toxicity signs and mortality; sub-chronic toxicity was evaluated through 14 days treatment with once-daily HAE doses (400 mg/kg, p.o.). The gastroprotective effect of HAE was demonstrated on the indomethacin-induced gastric ulcer model after the administration of extracts. Data comparison of ulcer index averages between saline and HAE (100 or 400 mg/kg, p.o.) groups showed significant (P < 0.01) inhibition (71.73 and 76.72 %, respectively) of indomethacin-induced gastric lesions. Histological analyses showed significant (P < 0.05) inhibition of leukocyte migration in HAE-treated groups. A fingerprint of the HAE obtained by HPLC/UV/MS analysis showed major peaks characteristic of sesquiterpene lactones. Compound 1 was isolated and elucidated as a new natural product. Its capacity to prevent leukocyte chemotaxis was demonstrated in vitro, corroborating the pharmacological effects observed for C. martii HAE.

Diagnostic usefulness of carbohydrate-deficient transferrin for detecting alcohol-related problems in hospitalized patients

We evaluated the diagnostic usefulness of carbohydrate-deficient transferrin (CDT) for detecting alcohol-related problems (ARP) in hospitalized patients, assessed potential differences according to gender and age, and compared this value to the other screening measures conventionally used, namely the CAGE questionnaire and standard biological markers MCV (mean corpuscular volume) and GGT (gamma-glutamyltransferase). CDT sensitivity for detecting ARP was 70%, specificity 75% and area under the receiver operating characteristic curve 0.76%. Its sensitivity was shown to be lower both in the female group (65 vs 71%) as well as in the younger-age group whereas its specificity was lower in the liver-damaged group (55%). CDT diagnostic value did not exceed that of CAGE (sensitivity 78% and specificity 99%), MCV (sensitivity and specificity 74%) or GGT (sensitivity 82% and specificity 53%) but was better than those of other biochemical measures. We conclude that CDT is an effective biological marker for the detection of ARP among hospitalized patients, but that its diagnostic usefulness does not exceed that of some other alternative measures commonly used.

Effect of epithelial debridement on human cornea proteoglycans

Corneal transparency is attributed to the regular spacing and diameter of collagen fibrils, and proteoglycans may play a role in fibrillogenesis and matrix assembly. Corneal scar tissue is opaque and this opacity is explained by decreased ultrastructural order that may be related to proteoglycan composition. Thus, the objectives of the present study were to characterize the proteoglycans synthesized by human corneal explants and to investigate the effect of mechanical epithelial debridement. Human corneas unsuitable for transplants were immersed in F-12 culture medium and maintained under tissue culture conditions. The proteoglycans synthesized in 24 h were labeled metabolically by the addition of (35)S-sulfate to the medium. These compounds were extracted by 4 M GuHCl and identified by a combination of agarose gel electrophoresis, enzymatic degradation with protease and mucopolysaccharidases, and immunoblotting. Decorin was identified as the main dermatan sulfate proteoglycan and keratan sulfate proteoglycans were also prominent components. When the glycosaminoglycan side chains were analyzed, only keratan sulfate and dermatan sulfate were detected (approximately 50% each). Nevertheless, when these compounds were (35)S-labeled metabolically, the label in dermatan sulfate was greater than in keratan sulfate, suggesting a lower synthesis rate for keratan sulfate. (35)S-Heparan sulfate also appeared. The removal of the epithelial layer caused a decrease in heparan sulfate labeling and induced the synthesis of dermatan sulfate by the stroma. The increased deposit of dermatan sulfate proteoglycans in the stroma suggests a functional relationship between epithelium and stroma that could be related to the corneal opacity that may appear after epithelial cell debridement.

Preparation and purification of Flavobacterium heparinum chondroitinases AC and B by hydrophobic interaction chromatography

Flavobacterium heparinum is a soil bacterium that produces several mucopolysaccharidases such as heparinase, heparitinases I and II, and chondroitinases AC, B, C and ABC. The purpose of the present study was to optimize the preparation of F. heparinum chondroitinases, which are very useful tools for the identification and structural characterization of chondroitin and dermatan sulfates. We observed that during the routine procedure for cell disruption (ultrasound, 100 kHz, 5 min) some of the chondroitinase B activity was lost. Using milder conditions (2 min), most of the chondroitinase B and AC protein was solubilized and the enzyme activities were preserved. Tryptic soy broth without glucose was the best culture medium both for bacterial growth and enzyme induction. Chondroitinases AC and B were separated from each other and also from glucuronidases and sulfatases by hydrophobic interaction chromatography on HP Phenyl-Sepharose. A rapid method for screening of the column fractions was also developed based on the metachromatic shift of the color of dimethylmethylene blue.