BMX controls 3βHSD1 and sex steroid biosynthesis in cancer

Prostate cancer is highly dependent on androgens and the androgen receptor (AR). Hormonal therapies inhibit gonadal testosterone production, block extragonadal androgen biosynthesis, or directly antagonize AR. Resistance to medical castration occurs as castration-resistant prostate cancer (CRPC) and is driven by reactivation of the androgen-AR axis. 3β-hydroxysteroid dehydrogenase-1 (3βHSD1) serves as the rate-limiting step for potent androgen synthesis from extragonadal precursors, thereby stimulating CRPC. Genetic evidence in men demonstrates the role of 3βHSD1 in driving CRPC. In postmenopausal women, 3βHSD1 is required for synthesis of aromatase substrates and plays an essential role in breast cancer. Therefore, 3βHSD1 lies at a critical junction for the synthesis of androgens and estrogens, and this metabolic flux is regulated through germline-inherited mechanisms. We show that phosphorylation of tyrosine 344 (Y344) occurs and is required for 3βHSD1 cellular activity and generation of Δ4, 3-keto-substrates of 5α-reductase and aromatase, including in patient tissues. BMX directly interacts with 3βHSD1 and is necessary for enzyme phosphorylation and androgen biosynthesis. In vivo blockade of 3βHSD1 Y344 phosphorylation inhibits CRPC. These findings identify what we believe to be new hormonal therapy pharmacologic vulnerabilities for sex-steroid dependent cancers.

Partial Versus Radical Nephrectomy: Complexity of Decision-Making and Utility of AUA Guidelines

INTRODUCTION

The American-Urological-Association(AUA) Guidelines for renal cancer(2017) recommend consideration for radical-nephrectomy(RN) over partial(PN) whenever there is increased oncologic-risk; and RN should be prioritized if three other criteria are all also met: 1) increased tumor-complexity; 2) no preexisting chronic-kidney-disease/ proteinuria, and 3) normal contralateral kidney that will likely provide estimated glomerular-filtration-rate (eGFR) >45ml/min/1.73m² even if RN is performed. Our objective was to assess the complexity of decision-making about RN/PN and utility of AUA Guidelines statements regarding this issue.

PATIENTS AND METHODS

Retrospective review of 267 consecutive RN/PN from 2019(100-RN/167-PN). High tumor-complexity was defined as R.E.N.A.L.≥9. Increased oncologic-risk was defined as tumor >7cm, locally-advanced or infiltrative-features on imaging, or high-risk pathology on biopsy, if obtained. New-baseline GFR after RN was estimated using global-GFR, split-renal-function_{contralateral}, and presuming 25% renal-functional-compensation.

RESULTS

163 patients(61%) fit scenarios that are well-defined in the Guidelines. Of these, 34 had strong indications for RN, and all had RN. Twelve of 129 patients(9.3%) underwent RN despite Guidelines generally favoring PN. The remaining 104 patients(39%) did not fit within situations where the Guidelines provide specific recommendations. In these patients, RN was often performed despite functional-considerations favoring PN due to overriding concerns about oncologic-risk and/or tumor-complexity.

CONCLUSION

Our data demonstrate complexity of decision-making about PN/RN as almost 40% of patients did not fit well-described AUA Guidelines descriptors. Compliance was generally strong although occasional overutilization of RN remains a concern in our series, and will be addressed with additional education. Further studies will be required to assess the generalizability of our findings in other institutions/settings.

Predicting GFR after radical nephrectomy: the importance of split renal function

PURPOSE

To evaluate a conceptually simple model to predict new-baseline-glomerular-filtration-rate (NBGFR) after radical nephrectomy (RN) based on split-renal-function (SRF) and renal-functional-compensation (RFC), and to compare its predictive accuracy against a validated non-SRF-based model. RN should only be considered when the tumor has increased oncologic potential and/or when there is concern about perioperative morbidity with PN due to increased tumor complexity. In these circumstances, accurate prediction of NBGFR after RN can be important, with a threshold NBGFR > 45 ml/min/1.73m² correlating with improved overall survival.

METHODS

236 RCC patients who underwent RN (2010-2012) with preoperative imaging (CT/MRI) and relevant functional data were included. NBGFR was defined as GFR 3-12 months post-RN. SRF was determined using semi-automated software that provides differential parenchymal-volume-analysis (PVA) from preoperative imaging. Our SRF-based model was: Predicted NBGFR = 1.24 (× Global GFR_Pre-RN) (× SRF_{Contralateral}), with 1.24 representing the mean RFC estimate from independent analyses. A non-SRF-based model was also assessed: Predicted NBGFR = 17 + preoperative GFR (× 0.65)-age (× 0.25) + 3 (if tumor > 7 cm)-2 (if diabetes). Alignment between predicted/observed NBGFR was assessed by comparing correlation coefficients and area-under-the-curve (AUC) analyses.

RESULTS

The correlation-coefficients (r) were 0.87/0.72 for SRF-based/non-SRF-based models, respectively (p = 0.005). For prediction of NBGFR > 45 ml/min/1.73m², the SRF-based/non-SRF-based models provided AUC of 0.94/0.87, respectively (p = 0.044).

CONCLUSION

Previous non-SRF-based models to predict NBGFR post-RN are complex and omit two important parameters: SRF and RFC. Our proposed model prioritizes these parameters and provides a conceptually simple, accurate, and clinically implementable approach to predict NBGFR post-RN. SRF can be easily obtained using PVA software that is affordable, readily available (FUJIFILM-Medical-Systems), and more accurate than nuclear-renal-scans. The SRF-based model demonstrates greater predictive-accuracy than a non-SRF-based model, including the clinically-important predictive-threshold of NBGFR > 45 ml/min/1.73m².

Clinical Activity and Safety of Cabozantinib for Brain Metastases in Patients With Renal Cell Carcinoma

Importance

Patients with brain metastases from renal cell carcinoma (RCC) have been underrepresented in clinical trials, and effective systemic therapy is lacking. Cabozantinib shows robust clinical activity in metastatic RCC, but its effect on brain metastases remains unclear.

Objective

To assess the clinical activity and toxic effects of cabozantinib to treat brain metastases in patients with metastatic RCC.

Design, Setting, and Participants

This retrospective cohort study included patients with metastatic RCC and brain metastases treated in 15 international institutions (US, Belgium, France, and Spain) between January 2014 and October 2020. Cohort A comprised patients with progressing brain metastases without concomitant brain-directed local therapy, and cohort B comprised patients with stable or progressing brain metastases concomitantly treated by brain-directed local therapy.

Exposures

Receipt of cabozantinib monotherapy at any line of treatment.

Main Outcomes and Measures

Intracranial radiological response rate by modified Response Evaluation Criteria in Solid Tumors, version 1.1, and toxic effects of cabozantinib.

Results

Of the 88 patients with brain metastases from RCC included in the study, 33 (38%) were in cohort A and 55 (62%) were in cohort B; the majority of patients were men (n = 69; 78%), and the median age at cabozantinib initiation was 61 years (range, 34-81 years). Median follow-up was 17 months (range, 2-74 months). The intracranial response rate was 55% (95% CI, 36%-73%) and 47% (95% CI, 33%-61%) in cohorts A and B, respectively. In cohort A, the extracranial response rate was 48% (95% CI, 31%-66%), median time to treatment failure was 8.9 months (95% CI, 5.9-12.3 months), and median overall survival was 15 months (95% CI, 9.0-30.0 months). In cohort B, the extracranial response rate was 38% (95% CI, 25%-52%), time to treatment failure was 9.7 months (95% CI, 6.0-13.2 months), and median overall survival was 16 months (95% CI, 12.0-21.9 months). Cabozantinib was well tolerated, with no unexpected toxic effects or neurological adverse events reported. No treatment-related deaths were observed.

Conclusions and Relevance

In this cohort study, cabozantinib showed considerable intracranial activity and an acceptable safety profile in patients with RCC and brain metastases. Support of prospective studies evaluating the efficacy of cabozantinib for brain metastases in patients with RCC is critical.

Preincision adjunctive prophylaxis for cesarean deliveries a systematic review and meta-analysis

OBJECTIVE

This study aimed to systematically review the relative effectiveness of preincision cefazolin with or without adjunctive prophylaxis (macrolides or metronidazole) vs cefazolin alone in decreasing the incidence of postcesarean delivery surgical site infections.

DATA SOURCES

We performed a systematic search on PubMed, Ovid EMBASE, Google Scholar, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials from October 25, 2020, to November 25, 2020, to identify studies comparing cefazolin with adjunctive macrolides or metronidazole with cefazolin alone. The reference lists were reviewed, and a manual search of articles published after the last database search was performed.

STUDY ELIGIBILITY CRITERIA

Overall, 3 randomized controlled trials and 1 prospective observational study of reproductive-age women undergoing cesarean deliveries were included in the study. We excluded studies of women who were immunocompromised (eg, patients who were HIV positive) or women with a diagnosis of chorioamnionitis before cesarean delivery. All patients received first-line cefazolin (either cefazolin 1 g or 2 g). We compared preincision cefazolin alone with preincision cefazolin plus adjunctive therapy (500 mg, oral or intravenous formulations of azithromycin, metronidazole, or clarithromycin).

METHODS

A total of 6 review authors independently assessed the risk of bias for each study, using the Cochrane Risk of Bias criteria. Synthesis and further appraisal were done using the Grading of Recommendations, Assessment, Development, and Evaluation levels and the American College of Obstetricians and Gynecologists appraisal guidelines. Disagreements were resolved by discussion. Treatment effects were evaluated using meta-analysis, and pooled relative risks and 95% confidence intervals were generated using random-effects models using the Review Manager 5 software (version 5.4.1).

RESULTS

Overall, 3 randomized controlled trials and 1 prospective observational study representing 2613 women met the criteria for inclusion. Significant reductions in surgical site infections (relative risk, 0.46; 95% confidence interval, 0.34-0.63; 3 randomized controlled trials) and the duration of hospital stay (weighted mean difference, -1.46; 95% confidence interval, -2.21 to -0.71; 2 randomized controlled trials) were observed with preincision cefazolin and adjunctive prophylaxis compared with cefazolin alone. No significant difference was observed in maternal febrile morbidity (relative risk, 0.38; 95% confidence interval, 0.11-1.25; 2 randomized controlled trials).

CONCLUSION

Our findings have provided evidence for the use of preincision adjunctive extended-spectrum prophylaxis with cefazolin over cefazolin alone. However, future investigations are required to establish the relative efficacies of different adjunctive antibiotic options.

P14.02 The Natural History of a Residual Intracranial Meningioma- Volumetric Growth and Predictors of Progression

BACKGROUND

Resection of meningioma leaves residual solid tumour in ~25% of patients. Selection for further treatment and follow-up strategy may benefit from knowledge of volumetric growth and associated prognostic factors.

MATERIAL AND METHODS

Growth rates were assessed using a linear mixed effects model, in a retrospective adult cohort that underwent subtotal resection of meningioma (2004–2018). Endpoints were re-treatment, end of follow-up or death. Cox regression analysis was used to identify prognostic factors for progression, defined using the Response Assessment in Neuro-Oncology (RANO) volumetric criteria.

RESULTS

236 patients were included. Mean age at surgery was 56.3 years (SD=13.7) and 73.7% were female. WHO grades were 1 (n=195, 82.6%), 2 (n=40, 16.9%) and 3 (n=1, 0.5%). Adjuvant fractionated radiotherapy (fRT) was administered to 34 patients (14.4%), with no propensity towards higher WHO grade or residual volume. Median pre-operative meningioma and post-operative residual volumes were 34.0cm3 (IQR 16.0–63.0) and 2.0cm3 (IQR 0.8–5.2), respectively. Median follow-up was 64 months (IQR 42–104). Median absolute growth rate (AGR) and relative growth rate (RGR) were 0.1cm3/year and 4.3%/year, respectively. According to RANO criteria, 132 (55.9%) patients progressed, of which 13 (9.8%) developed symptoms. Median progression-free survival was 56 months (95% CI 43.1–69.0). Multivariable analysis identified adjuvant fRT (HR 1.7, [95% CI 1.0–2.8], P=0.046), skull base location (HR 1.5, [95% CI 1.0–2.4], P=0.047) and Ki-67 index (HR 3.7 [95% CI 1.3–10.8], P=0.017) as prognostic factors for volumetric progression. WHO grade was not significant (HR 1.0, [95% CI 0.5–1.7], P=0.905). Forty-nine patients who progressed (37.1%) underwent further treatment: fRT (n=19), re-operation (n=15), Stereotactic radiosurgery (SRS) (n=10) and surgery+adjuvant fRT (n=5). Of those, 8 (16.3%) progressed further (after re-operation [n=6] and SRS [n=2]). Seven were treated with a 2nd re-operation (n=3), fRT (n=3), and SRS (n=1). One patient progressed after a 2nd reoperation and was treated with SRS, after which they remained stable. Median survival was not reached. 5- and 10-year overall survival (OS) was 96% and 86% respectively.

CONCLUSION

Growth rates of a residual meningioma vary with a dichotomy observed in progression rates. Half of patients with a residual meningioma showed radiological progression requiring multiple treatment to control the tumour. The other half demonstrate a more indolent course. Skull base location and higher Ki67 are important prognostic factors for progression and therefore, should be considered to stratify patients for adjuvant radiotherapy.

Identification of Somatic Gene Signatures in Circulating Cell-Free DNA Associated with Disease Progression in Metastatic Prostate Cancer by a Novel Machine Learning Platform

PURPOSE

Progression from metastatic castration-sensitive prostate cancer (mCSPC) to a castration-resistant (mCRPC) state heralds the lethal phenotype of prostate cancer. Identifying genomic alterations associated with mCRPC may help find new targets for drug development. In the majority of patients, obtaining a tumor biopsy is challenging because of the predominance of bone-only metastasis. In this study, we hypothesize that machine learning (ML) algorithms can identify clinically relevant patterns of genomic alterations (GAs) that distinguish mCRPC from mCSPC, as assessed by next-generation sequencing (NGS) of circulating cell-free DNA (cfDNA).

EXPERIMENTAL DESIGN

Retrospective clinical data from men with metastatic prostate cancer were collected. Men with NGS of cfDNA performed at a Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory at time of diagnosis of mCSPC or mCRPC were included. A combination of supervised and unsupervised ML algorithms was used to obtain biologically interpretable, potentially actionable insights into genomic signatures that distinguish mCRPC from mCSPC.

RESULTS

GAs that distinguish patients with mCRPC (n = 187) from patients with mCSPC (n = 154) (positive predictive value = 94%, specificity = 91%) were identified using supervised ML algorithms. These GAs, primarily amplifications, corresponded to androgen receptor, Mitogen-activated protein kinase (MAPK) signaling, Phosphoinositide 3-kinase (PI3K) signaling, G1/S cell cycle, and receptor tyrosine kinases. We also identified recurrent patterns of gene- and pathway-level alterations associated with mCRPC by using Bayesian networks, an unsupervised machine learning algorithm.

CONCLUSION

These results provide clinical evidence that progression from mCSPC to mCRPC is associated with stereotyped concomitant gain-of-function aberrations in these pathways. Furthermore, detection of these aberrations in cfDNA may overcome the challenges associated with obtaining tumor bone biopsies and allow contemporary investigation of combinatorial therapies that target these aberrations.

IMPLICATIONS FOR PRACTICE

The progression from castration-sensitive to castration-resistant prostate cancer is characterized by worse prognosis and there is a pressing need for targeted drugs to prevent or delay this transition. This study used machine learning algorithms to examine the cell-free DNA of patients to identify alterations to specific pathways and genes associated with progression. Detection of these alterations in cell-free DNA may overcome the challenges associated with obtaining tumor bone biopsies and allow contemporary investigation of combinatorial therapies that target these aberrations.

Complementary Role of Circulating Tumor DNA Assessment and Tissue Genomic Profiling in Metastatic Renal Cell Carcinoma

PURPOSE

The role of circulating cell-free tumor DNA (ctDNA) as an adjunct to tissue genomic profiling is poorly defined in metastatic renal cell carcinoma (mRCC). In this study, we aim to validate previous findings related to genomic alteration (GA) frequency in ctDNA and determine the concordance between ctDNA and tissue-based profiling in patients with mRCC.

EXPERIMENTAL DESIGN

Results of 839 patients with mRCC who had ctDNA assessment with a Clinical Laboratory Improvement Amendments (CLIA)-certified ctDNA assay between November 2016 and December 2019 were collected. Tissue-based genomic profiling was collected when available and concordance analysis between blood- and tissue-based testing was performed.

RESULTS

ctDNA was assessed in 839 patients (comprising 920 samples) with mRCC. GAs were detected in 661 samples (71.8%). Tissue-based GAs were assessed in 112 patients. Limiting our analyses to a common 73-/74-gene set and excluding samples with no ctDNA detected, a total of 228 mutations were found in tissue and blood. Mutations identified in tissue (34.7%; 42/121) were also identified via ctDNA, whereas 28.2% (42/149) of the mutations identified in liquid were also identified via tissue. Concordance between ctDNA and tissue-based profiling was inversely related to the time elapsed between these assays.

CONCLUSIONS

This study confirms the feasibility of ctDNA profiling in the largest mRCC cohort to date, with ctDNA identifying multiple actionable alterations. It also demonstrates that ctDNA and tissue-based genomic profiling are complementary, with both platforms identifying unique alterations, and confirms that the frequency of unique alterations increases with greater temporal separation between tests.

Correlation of baseline circulating tumor cells (CTC) and associated genomic profile with survival outcomes in patients (pts) with metastatic castration-sensitive prostate cancer (mCSPC) in a real-world cohort

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Background: We recently published, in the context of SWOG1216 trial in pts with mCSPC, that higher baseline CTC level were associated with inferior survival outcomes (Goldkorn. Agarwal, CCR, 2021). Here in, we validate these findings in a real world population of mCSPC and interrogate tumor genomic profile with respect to the CTC level. Methods: Eligibility criteria: new mCSPC receiving ADT without or with intensification (docetaxel or novel hormonal therapy) and enumeration of baseline CTCs by FDA cleared Cell Search CTC assay. Gene alterations were determined by comprehensive genomic profiling (CGP) of tumor tissue (Foundation Medicine). CTC counts were categorized as 0, 1-4 and ≥5/7.5 ml. Relationships between CTC counts and number (no.) of genes altered and individual gene alterations were assessed via Kruskal-Wallis and chi-squared tests, respectively. Relationships between progression-free survival (PFS), overall survival (OS) and individual mutations were assessed via log-rank tests. Relationships between CTC counts, PFS and OS were assessed by Cox proportional hazards models, both unadjusted and adjusted for multiple variables (Table). Results: Overall 103 pts were eligible. Median age: 67 yrs, Gleason score: 9, PSA at ADT initiation: 41 ng/mL. 67 (65%) pts had de-novo metastatic disease and 44 (43%) pts underwent ADT intensification therapy. Pts with greater CTC counts tended to have greater no. of altered genes (p=0.017), greater no. of total alterations (p=0.017) and higher rate of TP53 mutations (p=0.036). In univariate analyses (UVA) and multivariable analyses (MVA), both CTC counts and no. of genes altered were strongly associated with both PFS and OS (Table). CGP of tumors with respect to CTC counts will be presented in meeting. Conclusions: Herein, we validate our previous findings from SWOG1216 trial of association of higher CTC level with inferior survival outcomes in a real world mCSPC cohort. The CTC enriched population is associated with a distinct tumor genomic landscape, which may guide further drug development in this pt population at the highest risk of progression and/or death.[Table: see text]

Immunogenicity and safety of two monovalent rotavirus vaccines, ROTAVAC® and ROTAVAC 5D® in Zambian infants

BACKGROUND AND AIMS

ROTAVAC® (frozen formulation stored at -20 °C) and ROTAVAC 5D® (liquid formulation stable at 2-8 °C) are rotavirus vaccines derived from the 116E human neonatal rotavirus strain, developed and licensed in India. This study evaluated and compared the safety and immunogenicity of these vaccines in an infant population in Zambia.

METHODS

We conducted a phase 2b, open-label, randomized, controlled trial wherein 450 infants 6 to 8 weeks of age were randomized equally to receive three doses of ROTAVAC or ROTAVAC 5D, or two doses of ROTARIX®. Study vaccines were administered concomitantly with routine immunizations. Blood samples were collected pre-vaccination and 28 days after the last dose. Serum anti-rotavirus IgA antibodies were measured by ELISA, with WC3 and 89-12 rotavirus strains as viral lysates in the assays. The primary analysis was to assess non-inferiority of ROTAVAC 5D to ROTAVAC in terms of the geometric mean concentration (GMC) of serum IgA (WC3) antibodies. Seroresponse and seropositivity were also determined. Safety was evaluated as occurrence of immediate, solicited, unsolicited, and serious adverse events after each dose.

RESULTS

The study evaluated 388 infants in the per-protocol population. All three vaccines were well tolerated and immunogenic. The post-vaccination GMCs were 14.0 U/mL (95% CI: 10.4, 18.8) and 18.1 U/mL (95% CI: 13.7, 24.0) for the ROTAVAC and ROTAVAC 5D groups, respectively, yielding a ratio of 1.3 (95% CI: 0.9, 1.9), thus meeting the pre-set non-inferiority criteria. Solicited and unsolicited adverse events were similar across all study arms. No death or intussusception case was reported during study period.

CONCLUSIONS

Among Zambian infants, both ROTAVAC and ROTAVAC 5D were well tolerated and the immunogenicity of ROTAVAC 5D was non-inferior to that of ROTAVAC. These results are consistent with those observed in licensure trials in India and support use of these vaccines across wider geographical areas.

Activity and safety of cabozantinib (cabo) in brain metastases (BM) from metastatic renal cell carcinoma (mRCC): An international multicenter study

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Background: Cabo shows robust clinical activity in mRCC. Patients (pts) with BM have been underrepresented in clinical trials and effective systemic therapy is lacking. We retrospectively characterized the clinical activity and toxicity of cabo in pts with BM from RCC. Methods: Consecutive medical records from mRCC pts with BM treated with cabo monotherapy across 15 institutions were reviewed. Pts were grouped by radiologic presence (cohort 1) or absence (cohort 2) of progressing intracranial metastases. Brain-directed local therapy was allowed but radiological confirmation of intracranial progression at cabo start was required in cohort 1. Radiological response rate was investigator-assessed by modified RECIST 1.1 for intracranial and RECIST 1.1 for extracranial responses. Time to treatment failure (TTF) and overall survival (OS) were estimated by Kaplan-Meier. Results: We identified 69 pts with BM from RCC, 25 (36%) in cohort 1 and 44 (64%) in cohort 2. Majority were IMDC intermediate/poor (87%) and received cabo as ≥2nd line (75%). Median time from mRCC diagnosis to BM was 19.1 months (mos) (IQR 4.4-39.5). Overall, median number of BM was 3 (range 1-27) and median size of largest lesion was 1.2 cm (range 0.2-6.6) with frontal (62%) and parietal (48%) as the most frequent localizations. Prior brain directed therapy was used in 65% and 93% of pts in cohort 1 and 2 respectively. Median follow-up after cabo initiation was 11 mos (range 4-72). Twenty three percent of pts remained on therapy while 52% discontinued for progression and 9% for toxicity. Intracranial response rate was 61% (95%CI 39%-80%), with 3 complete responses, for cohort 1 and 57% (95%CI 41%-72%) for cohort 2. Only 10% (n = 7) had intracranial progression as best response. For cohort 1, extracranial response was 52% (95%CI 31%-72%), median TTF was 9.9 mos (95%CI 5.9-14.0) and OS was 14.7 mos (95%CI 7.7-23.0). For cohort 2, extracranial response was 41% (95%CI 26%-57%), TTF was 9.0 mos (95%CI 4.6-11.4) and OS was 14.1 mos (95%CI 11.0-22.0). Most common adverse events were fatigue (77%) and diarrhea (46%). Eight pts received concomitant brain-directed treatment during cabo therapy without neurological toxicities. Conclusions: Cabo shows significant intracranial activity and acceptable safety profile in pts with BM from RCC. [Table: see text]

Illustration of temporal evolution in patients with metastatic renal cell carcinoma (mRCC) using both circulating tumor DNA (ctDNA) and tissue-based genomic data

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Background: We have previously demonstrated the feasibility of ctDNA assessment in mRCC and preliminarily showed agreement between ctDNA and tissue-based genomic findings (Zengin et al ESMO 2020). Our data suggested that the degree of agreement is dependent upon the temporal separation of blood and tissue samples. We sought to further explore this temporal impact in a separate validation cohort. Methods: Patients (pts) with mRCC who underwent ctDNA genomic profiling were identified. ctDNA analysis was performed using a CLIA-certified 73-74 gene panel (Guardant360). From this cohort we identified a subset of pts who also underwent tissue-based genomic profiling using either a whole exome sequencing platform (GemExtra [TGen, Phoenix, AZ]) or a targeted next generation sequencing platform (Foundation Medicine [Cambridge, MA] or Tempus [Chicago, IL]). Only alterations covered by both assays were included for the current analysis. The difference in the proportion of alterations detected on tissue and ctDNA was compared between these cohorts and at a 6-mo landmark using the χ2 test. Results: In total, ctDNA and tissue based genomic profiling was assessed in 112 pts (M:F, 81:31); with most common histology was clear cell (85.7%). Median time between ctDNA and tissue assessments was 9.8 months (IQR 1.15-23.7). When examining paired samples in which >1 ctDNA alteration was detected, 32% (43/133) of alterations detected on tissue were also detected in ctDNA. This proportion increased to 43% (29/67) when samples collected within 6 months of each other, and was 51% (28/55) in samples collected within 3 months of each other. There was no significant difference in the frequency of shared mutations between the cohorts (P=0.09; Table). Conclusions: Our study confirms that ctDNA and tissue-based genomic profiling continue to provide consistently high levels of agreement. Notably, the percentage of samples with ≥1 ctDNA alteration detected was significantly lower in both cohorts compared to previous studies in RCC. More shared alterations were found on ctDNA when both ctDNA and tissue-based assessment were obtained at closer intervals. [Table: see text]

Association of circulating tumor cells (CTC) with survival outcomes in patients (pts) with metastatic castration-sensitive prostate cancer (mCSPC) in a real-world cohort

59

Background: In mCSPC, baseline CTC counts have been shown to correlate with PSA responses and progression free survival (PFS) in small studies in the context of androgen deprivation therapy (ADT) without modern intensification with docetaxel or novel hormonal therapy. Similar correlation of CTC count with PSA responses and PFS was recently reported from an ongoing phase 3 trial in mCSPC setting (SWOG1216) without reporting the association in the context of ADT intensification. Furthermore, none of these studies correlated CTCs with overall survival (OS). Herein we evaluated whether CTCs were associated with outcomes including OS in a real world mCPSC population treated with intensified as well as non-intensified ADT. Methods: Eligibility criteria: new mCSPC receiving ADT with or without intensification and enumeration of baseline CTCs by FDA cleared Cell Search CTC assay. The relationship between CTC counts (categorized as: 0, 1-4, and ≥5/7.5 ml) and both PFS and OS was assessed in the context of Cox proportional hazards models, both unadjusted and adjusted for age, Gleason, PSA at ADT initiation, de novo vs. non-de novo status, and ADT intensification vs. non-intensification therapy. Results: Overall 99 pts were identified. Baseline characteristics are summarized in Table. In unadjusted analyses, CTC counts of ≥5 as compared to 0 were strongly associated with inferior PFS (hazard ratio [HR] 3.38, 95% CI 1.85-6.18; p < 0.001) and OS (HR 4.44 95% CI 1.63-12.10; p = 0.004). In multivariate analyses, CTC counts of ≥5 as compared to 0 continued to be associated with inferior PFS (HR 5.49, 95% CI 2.64-11.43; p < 0.001) and OS (HR 4.00, 95% CI 1.31-12.23; p = 0.015). Within the ADT intensification subgroup also, high CTC counts were associated with poor PFS and OS. For PFS, the univariate HR for CTC ≥5 vs. 0 was 4.87 (95% CI 1.66-14.30; p = 0.004) and multivariate HR for CTC ≥5 vs. 0 was 7.43 (95% CI 1.92-28.82; p = 0.004). For OS, the univariate HR for CTC ≥5 vs. 0 was 15.88 (95% CI 1.93-130.58; p = 0.010) and multivariate HR for CTC ≥5 vs. 0 was 24.86 (95% CI 2.03-304.45; p = 0.012). Conclusions: To best of our knowledge this is the first study to show that high baseline CTC counts are strongly associated with inferior PFS as well as OS in pts with newly diagnosed mCSPC, even in those who received intensified ADT therapy. Identifying these pts at highest risk of progression and death can help with counselling and prognostication in clinics as well as design and enrollment in future clinical trials. [Table: see text]

Evaluation of the Safety and Efficacy of Immunotherapy Rechallenge in Patients With Renal Cell Carcinoma

Importance

Several immune checkpoint inhibitors (ICIs) are approved for use in patients with metastatic renal cell carcinoma (mRCC), but the efficacy and safety of ICI rechallenge in mRCC is unknown.

Objective

To evaluate the safety and efficacy of ICI rechallenge in patients with mRCC.

Design, Setting, and Participants

This multicenter, retrospective cohort study included consecutive patients with mRCC from 9 institutions in the US who received at least 2 separate lines of ICI (ICI-1, ICI-2) between January 2012 and December 2019.

Exposure

Receipt of an ICI (anticytotoxic T-lymphocyte-associated protein 4, anti-programmed cell death protein 1, or anti-programmed cell death ligand 1), alone or in combination with other therapies, in at least 2 separate lines of therapy for mRCC.

Main Outcomes and Measures

Investigator-assessed best overall response and immune-related adverse events.

Results

A total of 69 patients were included. Median (range) age at diagnosis of mRCC was 61 (36-86) years. Of these, 50 were men and 19 were women. The most common therapies received at ICI-1 were single-agent ICI (n = 27 [39%]) or ICI in combination with targeted therapy (n = 29 [42%]), while at ICI-2, the most common therapies were single-agent ICI (n = 26 [38%]) or dual ICI (n = 22 [32%]). Most patients discontinued ICI-1 owing to disease progression (n = 50 [72%]) or toxic effects (n = 16 [23%]). The overall response rates at ICI-1 and ICI-2 were 37% and 23%, respectively. The likelihood of a response at ICI-2 was greatest among patients who had previously responded to ICI-1 (7 of 24 [29%]), although responses at ICI-2 were seen in those who had progressive disease as their best response following ICI-1 (3 of 14 [21%]) as well as in those who received single-agent ICI at ICI-2 (7 of 23 [30%]). Grade 3 or higher immune-related adverse events were seen in 18 patients (26%) and 11 patients (16%) at ICI-1 and ICI-2, respectively. There were no treatment-related deaths.

Conclusions and Relevance

The findings of this multicenter cohort study suggest that ICI rechallenge in patients with mRCC may be safe and reasonably efficacious, with an overall response rate of 23%. Data from prospective studies are needed to validate these findings and determine the role of sequential ICI regimens in treatment of mRCC.

Cabozantinib real-world effectiveness in the first-through fourth-line settings for the treatment of metastatic renal cell carcinoma: Results from the International Metastatic Renal Cell Carcinoma Database Consortium

Background

Cabozantinib is approved for metastatic renal cell carcinoma (mRCC) based on the METEOR and CABOSUN trials. However, real‐world effectiveness and dosing patterns of cabozantinib are not well characterized.

Methods

Patients with mRCC treated with cabozantinib between 2011 and 2019 were identified and stratified using the International mRCC Database Consortium (IMDC) risk groups. First‐ (1L), second‐ (2L), third‐ (3L), and fourth‐line (4L) overall response rate (ORR), time to treatment failure (TTF), and overall survival (OS) were analyzed. Dose reduction rates and their association with TTF and OS were determined.

Results

A total of 413 patients were identified. The ORRs across 1L to 4L were 32%, 26%, 25%, and 29%, respectively, and the median TTF rates were 8.3, 7.3, 7.0, and 8.0 months, respectively. The median OS (mOS) rates in 1L to 4L were 30.7, 17.8, 12.6, and 14.9 months, respectively. For patients treated with 1L PD(L)1 combination agent (n = 31), 2L cabozantinib had ORR of 22%, median TTF of 5.4 months, and mOS of 17.4 months. About 50% (129/258) of patients required dose reductions. The TTF and mOS were significantly longer for patients who required dose reduction vs. patients who did not, with an adjusted hazard ratio of 0.37 (95% CI 0.202–0.672, p < 0.01) and 0.46 (95% CI 0.215–0.980, p = 0.04), respectively. Limitations include the retrospective study design and the lack of central radiology review.

Conclusion

The ORR and TTF of cabozantinib were maintained from the 1L to 4L settings. Dose reductions due to toxicity were associated with improved TTF and OS. Cabozantinib has clinical activity after 1L Immuno‐oncology combination agents.

Evolving Role of Immunotherapy in Metastatic Castration Refractory Prostate Cancer

Immunotherapies have shown remarkable success in the treatment of multiple cancer types; however, despite encouraging preclinical activity, registration trials of immunotherapy in prostate cancer have largely been unsuccessful. Sipuleucel-T remains the only approved immunotherapy for the treatment of asymptomatic or minimally symptomatic metastatic castrate-resistant prostate cancer based on modest improvement in overall survival. This immune evasion in the case of prostate cancer has been attributed to tumor-intrinsic factors, an immunosuppressive tumor microenvironment, and host factors, which ultimately make it an inert 'cold' tumor. Recently, multiple approaches have been investigated to turn prostate cancer into a 'hot' tumor. Antibodies directed against programmed cell death protein 1 have a tumor agnostic approval for a small minority of patients with microsatellite instability-high or mismatch repair-deficient metastatic prostate cancer. Herein, we present an overview of the current immunotherapy landscape in metastatic castration-resistant prostate cancer with a focus on immune checkpoint inhibitors. We describe the results of clinical trials of immune checkpoint inhibitors in patients with metastatic castration-resistant prostate cancer; either as single agents or in combination with other checkpoint inhibitors, poly (ADP-ribose) polymerase (PARP) inhibitors, tyrosine kinase inhibitors, novel hormonal therapies, chemotherapies, and radioligands. Finally, we review upcoming immunotherapies, including novel monoclonal antibodies, chimeric-antigen receptor (CAR) T cells, Bi-Specific T cell Engagers (BiTEs), therapies targeting the adenosine pathway, and other miscellaneous agents.

Tumor Frameshift Mutation Proportion Predicts Response to Immunotherapy in Mismatch Repair-Deficient Prostate Cancer

Background

Genomic biomarkers that predict response to anti‐PD1 therapy in prostate cancer are needed. Frameshift mutations are predicted to generate more neoantigens than missense mutations; therefore, we hypothesized that the number or proportion of tumor frameshift mutations would correlate with response to anti‐PD1 therapy in prostate cancer.

Methods

To enrich for response to anti‐PD1 therapy, we assembled a multicenter cohort of 65 men with mismatch repair‐deficient (dMMR) prostate cancer. Patient characteristics and outcomes were determined by retrospective chart review. Clinical somatic DNA sequencing was used to determine tumor mutational burden (TMB), frameshift mutation burden, and frameshift mutation proportion (FSP), which were correlated to outcomes on anti‐PD1 treatment. We subsequently used data from a clinical trial of pembrolizumab in patients with nonprostatic dMMR cancers of various histologies as a biomarker validation cohort.

Results

Nineteen of 65 patients with dMMR metastatic castration‐resistant prostate cancer were treated with anti‐PD1 therapy. The PSA₅₀ response rate was 65%, and the median progression‐free survival (PFS) was 24 (95% confidence interval 16–54) weeks. Tumor FSP, more than overall TMB, correlated most strongly with prolonged PFS and overall survival (OS) on anti‐PD1 treatment and with density of CD8+ tumor‐infiltrating lymphocytes. High FSP similarly identified patients with longer PFS as well as OS on anti‐PD1 therapy in a validation cohort.

Conclusion

Tumor FSP correlated with prolonged efficacy of anti‐PD1 treatment among patients with dMMR cancers and may represent a new biomarker of immune checkpoint inhibitor sensitivity.

Implications for Practice

Given the modest efficacy of immune checkpoint inhibition (ICI) in unselected patients with advanced prostate cancer, biomarkers of ICI sensitivity are needed. To facilitate biomarker discovery, a cohort of patients with DNA mismatch repair‐deficient (dMMR) prostate cancer was assembled, as these patients are enriched for responses to ICI. A high response rate to anti‐PD1 therapy in these patients was observed; however, these responses were not durable in most patients. Notably, tumor frameshift mutation proportion (FSP) was identified as a novel biomarker that was associated with prolonged response to anti‐PD1 therapy in this cohort. This finding was validated in a separate cohort of patients with nonprostatic dMMR cancers of various primary histologies. This works suggests that FSP predicts response to anti‐PD1 therapy in dMMR cancers, which should be validated prospectively in larger independent cohorts.

Biomarkers of immune checkpoint inhibition sensitivity are needed. This article reports on genomic biomarkers that may predict response to anti‐PD1 therapy in prostate cancer.

Assessing the Structures and Interactions of γD-Crystallin Deamidation Variants

Cataracts involve the deposition of the crystallin proteins in the vertebrate eye lens, causing opacification and blindness. They are associated with either genetic mutation or protein damage that accumulates over the lifetime of the organism. Deamidation of Asn residues in several different crystallins has been observed and is frequently invoked as a cause of cataract. Here, we investigated the properties of Asp variants, deamidation products of γD-crystallin, by solution NMR, X-ray crystallography, and other biophysical techniques. No substantive structural or stability changes were noted for all seven Asn to Asp γD-crystallins. Importantly, no changes in diffusion interaction behavior could be detected. Our combined experimental results demonstrate that introduction of single Asp residues on the surface of γD-crystallin by deamidation is unlikely to be the driver of cataract formation in the eye lens.

Unveiling barriers and facilitators to physical activity participation among urban Indian men

Purpose

Regular participation in physical activity is critical for nurturing optimum health and well-being. It also prevents the onset of obesity and associated non-communicable diseases. Indeed, urban Indian men are more prone to these chronic illnesses as most of them lead a very sedentary lifestyle. Thus, a public health priority is to increase physical activity levels among sedentary urban Indian men. With this objective in mind, an exploratory study was designed to understand men's perspective of physical activity and the factors influencing physical activity participation.

Methods

Five focus group discussions (FGDs) were conducted with adult men (n = 26; age: 20-60 years) between August and November 2019. The participants were recruited from Mumbai Metropolitan Area through snowballing. All the FGDs were audio-recorded and conducted in both Hindi and English. The audio recordings were transcribed and translated. Content analysis was used to obtain frequencies of different barriers and facilitators. Thematic analysis was applied to cluster responses, identify themes in the data, and build an explanation from the FGDs.

Results

All the participants perceived the need to participate in physical activity as it was associated with a better quality of life. Commonly identified facilitators were health benefits, physical appearance, and adequate facilities in the neighbourhood to engage in physical activity. Self-reported barriers included lack of time because of hectic work schedules and commuting, laziness, physical activity not viewed as a priority, and engagement with mobile phones.

Conclusions

The emerging findings can inform the development of a physical activity intervention to support behaviour change as well as ensure its sustainability among inactive urban Indian men. This qualitative inquiry contributes to the body of knowledge on physical activity in a culture that is relatively underrepresented in the current literature.

Key messages

Physical activity was influenced by multiple factors at multiple levels i.e. intrapersonal level, interpersonal level, and community level. There is a need to design effective public health interventions to increase physical activity and thereby control the prevailing disease burden.

Use of immune checkpoint inhibitors (ICIs) after prior ICI in metastatic renal cell carcinoma (mRCC): Results from a multicenter collaboration

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Background: Several ICIs are used in first and subsequent lines of therapy for mRCC, either alone or in combination with another ICI or targeted therapy (TT). There are no data on the efficacy and safety of using an ICI in patients who have already received an ICI in a prior line of therapy. Methods: We reviewed patients with mRCC at 8 institutions who received 2 separate lines of ICI therapy (ICI-1, ICI-2), including as a single-agent and/or combination with other agents. The primary outcomes were overall response rate (ORR) and time to progression (TTP) with ICI-1 and ICI-2. Immune-related adverse events (irAEs) were graded using CTCAEv5.0. Results: 65 patients were included. Median age at diagnosis of mRCC was 60 years (range 30-86) and the majority had clear cell RCC (n=56, 86%). Median follow-up was 3.5 years (95% CI 2.9-4.4). Median lines at which ICI-1 and ICI-2 were received were 1 (1-6) and 3 (2-8) respectively. Reasons for discontinuing ICI-1 were disease progression (n=47, 72%), toxicity (n=15, 23%) or other (n=3, 5%). Therapies received at ICI-2 were single-agent ICI (n=26, 40%), or combinations of ICI with another ICI (n=20, 31%), TT (n=11, 17%) or other agent (n=8, 12%). Responses to ICI-1 and ICI-2 are shown in the Table; ORR to ICI-2 was significantly lower than to ICI-1 (23% vs. 36%, p=0.044). Amongst those who responded to ICI-2 (n=14), 7 (50%) received single-agent ICI, and the remainder received ICI in combination with another ICI (n=4, 29%) or TT (n=3, 21%); 7 patients (50%) had previously responded to ICI-1. The ORR to ICI-2 was higher in responders to ICI-1 (32%) compared to those with SD (17%) or PD (15%) to ICI-1. Median TTP (mTTP) at ICI-2 was shorter compared to ICI-1 (5.3 months vs. 8.5 months, Wilcoxon p=0.024). 29 patients (45%) experienced an irAE with ICI-2; 8 (12%) and 3 (5%) had a grade 3 or 4 irAE respectively, with 3 (30%) of these patients having previously had ≥grade 3 irAE to ICI-1. There were no treatment-related deaths. Conclusions: The ORR to ICI-2 was 23%, which is comparable to that seen with ICI after prior TT. Responses were seen even amongst those receiving single-agent ICI at ICI-2 and the likelihood of response to ICI-2 was higher if a patient had previously responded to ICI-1. No increase in toxicity with ICI-2 was apparent. Additional data from prospective studies are needed to determine whether sequential ICI has a role in treatment of mRCC. [Table: see text]

Overall survival (OS) with docetaxel (D) vs novel hormonal therapy (NHT) with abiraterone (A) or enzalutamide (E) after a prior NHT in patients (Pts) with metastatic prostate cancer (mPC): Results from a real-world dataset

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Background: NHT (A and E) are approved first-line (1L) treatment (Rx) for mPC. After progression on NHT, Rx include either alternate NHT or D. However, OS from a randomized trial comparing NHT vs D after progression on 1L NHT has not been reported. Methods: Pts data were extracted from the Flatiron Health EHR-derived de-identified database. Inclusion: diagnosis of mPC; 1L Rx with single agent A or E only, single-agent Rx with alternate NHT (E or A) or D in second line (2L). Exclusion: > 180 days between date of diagnosis of mPC and date of next visit to ensure Pts were actively engaged in care at data-providing site; Rx with NHT in non-metastatic setting, any prior exposure to D. OS was compared using Cox proportional hazards model stratified by Rx propensity score. Each Pts’ probability of receiving D (rather than NHT) was modeled via a random forest based on Pts and disease characteristics which may drive treatment selection. These included pre-2L Rx ECOG scores, PSA, LDH, ALPH, Hb, age, ICD codes for liver metastasis, diabetes, neuropathy, and heart failure; insurance payer, year of start of 2L Rx, time on 1 L NHT, Gleason score, PSA at the original diagnosis of mPC. Subgroup analyses included 1L Rx duration < 12 mos. Results: 1165 Pts between 2/5/2013 to 9/27/2019 were eligible. Median follow up 8 mos (range 0.1-64.5). Median OS after 1L A was higher with E as compared to D (15.7 vs. 9.4 mos). Median OS after 1L E was higher with A as compared to D (13.3 vs. 9.7 mos) (table). Propensity distributions were overlapping among Rx arms and showed only modest imbalance. In 2L, D had a worse adjusted hazard ratio of 1.29 and 1.35 as compared to E and A respectively (p < 0.05). Similar results were seen with 1L Rx duration of < 12 mos (p < 0.05). Conclusions: These hypothesis-generating data provide real-world OS estimates with 2L D & NHT in mPC. In propensity-stratified analyses, mPC Pts who progressed on NHT had a worse OS with 2L D as compared to alternate NHT. Results were consistent in unadjusted analysis & subgroup analyses of 1L Rx < 12 mos. Results are subject to residual confounding and missingness. After prospective validation these data may aid in Rx sequencing, Pts counselling, and design of future clinical trials in this setting. [Table: see text]