Treatment Patterns and Attrition With Lines of Therapy for Advanced Urothelial Carcinoma in the US.

Importance: The treatment paradigm for advanced urothelial carcinoma (aUC) has undergone substantial transformation due to the introduction of effective, novel therapeutic agents. However, outcomes remain poor, and little is known about current treatment approaches and attrition rates for patients with aUC. Objectives: To delineate evolving treatment patterns and attrition rates in patients with aUC using a US-based patient-level sample. Design, Setting, and Participants: This retrospective cohort study used patient-level data from the nationwide deidentified electronic health record database Flatiron Health, originating from approximately 280 oncology clinics across the US. Patients included in the analysis received treatment for metastatic or local aUC at a participating site from January 1, 2011, to January 31, 2023. Patients receiving treatment for 2 or more different types of cancer or participating in clinical trials were excluded from the analysis. Main Outcomes and Measures: Frequencies and percentages were used to summarize the (1) treatment received in each line (cisplatin-based regimens, carboplatin-based regimens, programmed cell death 1 and/or programmed cell death ligand 1 [PD-1/PD-L1] inhibitors, single-agent nonplatinum chemotherapy, enfortumab vedotin, erdafitinib, sacituzumab govitecan, or others) and (2) attrition of patients with each line of therapy, defined as the percentage of patients not progressing to the next line. Results: Of the 12 157 patients within the dataset, 7260 met the eligibility criteria and were included in the analysis (5364 [73.9%] men; median age at the start of first-line treatment, 73 [IQR, 66-80] years). All patients commenced first-line treatment; of these, only 2714 (37.4%) progressed to receive second-line treatment, and 857 (11.8%) advanced to third-line treatment. The primary regimens used as first-line treatment contained carboplatin (2241 [30.9%]), followed by PD-1/PD-L1 inhibitors (2174 [29.9%]). The PD-1/PD-L1 inhibitors emerged as the predominant choice in the second- and third-line (1412 of 2714 [52.0%] and 258 of 857 [30.1%], respectively) treatments. From 2019 onward, novel therapeutic agents were increasingly used in second- and third-line treatments, including enfortumab vedotin (219 of 2714 [8.1%] and 159 of 857 [18.6%], respectively), erdafitinib (39 of 2714 [1.4%] and 28 of 857 [3.3%], respectively), and sacituzumab govitecan (14 of 2714 [0.5%] and 34 of 857 [4.0%], respectively). Conclusions and Relevance: The findings of this cohort study suggest that approximately two-thirds of patients with aUC did not receive second-line treatment. Most first-line treatments do not include cisplatin-based regimens and instead incorporate carboplatin- or PD-1/PD-L1 inhibitor-based therapies. These data warrant the provision of more effective and tolerable first-line treatments for patients with aUC.

Differences in Tumor Gene Expression Profiles Between De Novo Metastatic Castration-sensitive Prostate Cancer and Metastatic Relapse After Prior Localized Therapy.

BACKGROUND AND OBJECTIVE: It has been reported that patients with de novo metastatic castration-sensitive prostate cancer (dn-mCSPC) have worse prognosis and outcomes than those whose cancer relapses after prior local therapy (PLT-mCSPC). Our aim was to interrogate and validate underlying differences in tumor gene expression profiles between dn-mCSPC and PLT-mCSPC. METHODS: The inclusion criteria were histologically confirmed prostate adenocarcinoma and the availability of RNA sequencing data for treatment-naïve primary prostate tissue. RNA sequencing was performed by Tempus or Caris Life Sciences, both of which have Clinical Laboratory Improvement Amendments certification. The Tempus cohort was used for interrogation, while the Caris cohort was used for validation. Differential gene expression analysis between the cohorts was conducted using the DEseq2 pipeline. The resulting gene expression profiles were further analyzed using Gene Set Enrichment software to identify pathways with enrichment in each cohort. KEY FINDINGS AND LIMITATIONS: Overall, 128 patients were eligible, of whom 78 were in the Tempus cohort (dn-mCSPC 37, PLT-mCSPC 41) and 50 were in the Caris cohort (dn-mCSPC 30, PLT-mCSPC 20). Tumor tissues from patients with dn-mCSPC had higher expression of genes associated with inflammation pathways, while tissues from patients with PLT-mCSPC had higher expression of genes involved in oxidative phosphorylation, fatty acid metabolism, and androgen response pathways. CONCLUSIONS AND CLINICAL IMPLICATIONS: Our study revealed upregulation of distinct genomic pathways in dn-mCSPC in comparison to PLT-mCSPC. These hypothesis-generating data could guide personalized therapy for men with prostate cancer and explain different survival outcomes for dn-mCSPC and PLT-mCSPC. PATIENT SUMMARY: We measured gene expression levels in tumors from patients with metastatic castration-sensitive prostate cancer. In patients with metastatic disease at first diagnosis, inflammatory pathways were upregulated. In patients whose metastasis occurred on relapse after treatment, androgen response pathways were upregulated. These findings could help in personalizing therapy for prostate cancer and explaining differences in survival.

Natural course of metastatic castration-resistant prostate cancer in the era of intensified androgen deprivation therapy in the hormone-sensitive setting.

BACKGROUND: Androgen deprivation therapy (ADT) intensification (ADTi) (i.e., ADT with androgen receptor pathway inhibitor or docetaxel, or both) has significantly improved survival outcomes of patients with metastatic hormone-sensitive prostate cancer (mHSPC). However, the impact of prior ADTi in the mHSPC setting on the disease presentation and survival outcomes in metastatic castration-resistant prostate cancer (mCRPC) is not well characterized. In this study, our objective was to compare the disease characteristics and survival outcomes of patients with new mCRPC with respect to receipt of intensified or nonintensified ADT in the mHSPC setting. METHODS: In this institutional review board-approved retrospective study, eligibility criteria were as follows: patients diagnosed with mCRPC, treated with an approved first-line mCRPC therapy, and who received either intensified or nonintensified ADT in the mHSPC setting. Progression-free survival (PFS) was defined from the start of first-line therapy for mCRPC to progression per Prostate Cancer Working Group 2 criteria or death, and overall survival (OS) was defined from the start of first-line therapy for mCRPC to death or censored at the last follow-up. A multivariable analysis using the Cox proportional hazards model was used, adjusting for potential confounders. RESULTS: Patients (n = 387) treated between March 20, 2008, and August 18, 2022, were eligible and included: 283 received nonintensified ADT, whereas 104 were treated with ADTi. At mCRPC diagnosis, patients in the ADTi group were significantly younger, had more visceral metastasis, lower baseline prostate-specific antigen (all p < 0.01), and lower hemoglobin (p = 0.027). Furthermore, they had significantly shorter PFS (median 4.8 vs. 8.4 months, adjusted hazard ratio [HR]: 1.46, 95% confidence interval [95% CI]: 1.07-2, p = 0.017) and OS (median 21.3 vs. 33.1 months, adjusted HR: 1.53, 95% CI: 1.06-2.21, p = 0.022) compared to patients in the nonintensified ADT group. CONCLUSION: Patients treated with ADTi in the mHSPC setting and experiencing disease progression to mCRPC had more aggressive disease features of mCRPC (characterized by a higher number of poor prognostic factors at mCRPC presentation). They also had shorter PFS on first-line mCRPC treatment and shorter OS after the onset of mCRPC compared to those not receiving ADTi in the mHSPC setting. Upon external validation, these findings may impact patient counseling, prognostication, treatment selection, and design of future clinical trials in the mCRPC setting. There remains an unmet need to develop novel life-prolonging therapies with new mechanisms of action to improve mCRPC prognosis in the current era.

Impact of smoking status on clinical outcomes in patients with metastatic renal cell carcinoma treated with first-line immune checkpoint inhibitor-based regimens.

BACKGROUND: Current tobacco smoking is independently associated with decreased overall survival (OS) among patients with metastatic renal cell carcinoma (mRCC) treated with targeted monotherapy (VEGF-TKI). Herein, we assess the influence of smoking status on the outcomes of patients with mRCC treated with the current first-line standard of care of immune checkpoint inhibitor (ICI)-based regimens. MATERIALS AND METHODS: Real-world data from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) were collected retrospectively. Patients with mRCC who received either dual ICI therapy or ICI with VEGF-TKI in the first-line setting were included and were categorized as current, former, or nonsmokers. The primary outcomes were OS, time to treatment failure (TTF), and objective response rate (ORR). OS and TTF were compared between groups using the log-rank test and multivariable Cox regression models. ORR was assessed between the 3 groups using a multivariable logistic regression model. RESULTS: A total of 989 eligible patients were included in the analysis, with 438 (44.3%) nonsmokers, 415 (42%) former, and 136 (13.7%) current smokers. Former smokers were older and included more males, while other baseline characteristics were comparable between groups. Median follow-up for OS was 21.2 months. In the univariate analysis, a significant difference between groups was observed for OS (P = .027) but not for TTF (P = .9), with current smokers having the worse 2-year OS rate (62.8% vs 70.8% and 73.1% in never and former smokers, respectively). After adjusting for potential confounders, no significant differences in OS or TTF were observed among the 3 groups. However, former smokers demonstrated a higher ORR compared to never smokers (OR 1.45, P = .02). CONCLUSION: Smoking status does not appear to independently influence the clinical outcomes to first-line ICI-based regimens in patients with mRCC. Nonetheless, patient counseling on tobacco cessation remains a crucial aspect of managing patients with mRCC, as it significantly reduces all-cause mortality.

Impact of Synchronous versus Metachronous Metastasis on Outcomes in Patients with Metastatic Renal Cell Carcinoma Treated with First-line Immune Checkpoint Inhibitor-based Combinations.

BACKGROUND AND OBJECTIVE: The impact of time of metastasis onset with respect toprimary renal cell carcinoma (RCC) diagnosis on survival outcomes is not well characterized in the era of immune checkpoint inhibitor (ICI)-based combinations. Herein, we assessed differences in clinical outcomes between synchronous and metachronous metastatic RCC (mRCC). METHODS: Data for patients with mRCC treated with first-line ICI-based combination therapies between 2014 and 2023 were retrospectively collected. Patients were categorized as having synchronous metastasis if present within 3 mo of RCC diagnosis; metachronous metastasis was defined as metastasis >3 mo after primary diagnosis. Time to treatment failure (TTF), overall survival (OS), and the disease control rate (DCR) were assessed. KEY FINDINGS AND LIMITATIONS: Our analysis included 223 eligible patients (126 synchronous and 97 metachronous). Median TTF did not significantly differ between the synchronous and metachronous groups (9 vs 19.8 mo; p = 0.063). Median OS was significantly shorter in the synchronous group (28.0 vs 50.9 mo; p = 0.001). Similarly, patients with synchronous metachronous metastasis (58.7% vs. 78.4%; p = 0.002). On multivariable analyses, synchronous metastasis remained independently associated with worse OS and DCR. CONCLUSIONS AND CLINICAL IMPLICATIONS: In this hypothesis-generating study, patients with mRCC with synchronous metastasis who were treated with first-line ICI-based combinations have a poorer OS and worse DCR than those with metachronous mRCC. If these results are externally validated, time to metastasis could be included in prognostic models for mRCC. PATIENT SUMMARY: Our study demonstrates that patients treated with current first-line immunotherapies, who present with metastasis at the initial diagnosis of kidney cancer have worse overall survival compared to those who develop metastasis later. These results can help physicians and patients understand life expectancy.

Cabozantinib with immune checkpoint inhibitor versus cabozantinib monotherapy in patients with metastatic clear cell renal cell carcinoma progressing after prior immune checkpoint inhibitor.

INTRODUCTION: Rechallenge with antibodies targeting programmed cell death protein-1 or its ligand (PD-1/L1) after discontinuation or disease progression in solid tumors following a prior PD-1/L1 treatment is often practiced in clinic. This study aimed to investigate if adding PD-1/L1 inhibitors to cabozantinib, the most used second-line treatment in real-world patients with metastatic clear cell renal cell carcinoma (mccRCC), offers additional benefits. METHODS: Using de-identified patient-level data from a large real-world US-based database, patients diagnosed with mccRCC, who received any PD-1/L1-based combination in first-line (1L) setting, followed by second-line (2L) therapy with either cabozantinib alone or in combination with PD-1/L1 inhibitors were included. Patients given a cabozantinib-containing regimen in 1L were excluded. The study end points were real-world time to next therapy (rwTTNT) and real-world overall survival (rwOS) by 2L. RESULTS: Of 12,285 patients with metastatic renal cell carcinoma in the data set, 348 patients met eligibility and were included in the analysis. After propensity score matching weighting, cabozantinib with PD-1/L1 inhibitors versus cabozantinib (ref.) had similar rwTTNT and rwOS in the 2L setting. Hazard ratios and 95% confidence interval (CI) for rwTTNT and rwOS are 0.74 (95% CI, 0.49-1.12) and 1.15 (95% CI, 0.73-1.79), respectively. CONCLUSION: In this study, the results align with the phase 3 CONTACT-03 trial results, which showed no additional benefit of adding PD-L1 inhibitor to cabozantinib compared to cabozantinib alone in 2L following PD-1/L1-based therapies in 1L. These results from real-world patients strengthen the evidence regarding the futility of rechallenge with PD-1/L1 inhibitors.

Comparison of outcomes for Hispanic and non-Hispanic patients with advanced renal cell carcinoma in the International Metastatic Renal Cell Carcinoma Database.

BACKGROUND: Existing data on the impact of Hispanic ethnicity on outcomes for patients with renal cell carcinoma (RCC) is mixed. The authors investigated outcomes of Hispanic and non-Hispanic White (NHW) patients with advanced RCC receiving systemic therapy at large academic cancer centers using the International Metastatic Renal Cell Carcinoma Database (IMDC). METHODS: Eligible patients included non-Black Hispanic and NHW patients with locally advanced or metastatic RCC initiating systemic therapy. Overall survival (OS) and time to first-line treatment failure (TTF) were calculated using the Kaplan-Meier method. The effect of ethnicity on OS and TTF were estimated by Cox regression hazard ratios (HRs). RESULTS: A total of 1563 patients (181 Hispanic and 1382 NHW) (mostly males [73.8%] with clear cell RCC [81.5%] treated with tyrosine kinase inhibitor [TKI] monotherapy [69.9%]) were included. IMDC risk groups were similar between groups. Hispanic patients were younger at initial diagnosis (median 57 vs. 59 years, p = .015) and less likely to have greater than one metastatic site (60.8% vs. 76.8%, p < .001) or bone metastases (23.8% vs. 33.4%, p = .009). Median OS and TTF was 38.0 months (95% confidence interval [CI], 28.1-59.2) versus 35.7 months (95% CI, 31.9-39.2) and 7.8 months (95% CI, 6.2-9.0) versus 7.5 months (95% CI, 6.9-8.1), respectively, in Hispanic versus NHW patients. In multivariable Cox regression analysis, no statistically significant differences were observed in OS (adjusted hazard ratio [HR], 1.07; 95% CI, 0.86-1.31, p = .56) or TTF (adjusted HR, 1.06; 95% CI, 0.89-1.26, p = .50). CONCLUSIONS: The authors did not observe statistically significant differences in OS or TTF between Hispanic and NHW patients with advanced RCC. Receiving treatment at tertiary cancer centers may mitigate observed disparities in cancer outcomes.

Histologic patterns in prostatic adenocarcinoma are not predictive of mutations in the homologous recombination repair pathway.

Somatic or germline homologous recombination repair (HRR) pathway gene mutations are commonly detected in prostate cancer, especially in advanced disease, and are associated with response to poly (ADP-ribose) polymerase (PARP) inhibitors. In this study, we evaluated whether histological patterns are predictive of HRR pathway gene mutations. The study population comprised 130 patients with advanced prostate carcinoma who underwent comprehensive genomic profiling (CGP) of tumor tissue at a CLIA-certified laboratory. HRR genes in the study included BRCA1, BRCA2, ATM, BARD1, BRIP, CHEK2, MRE11A, NBN, PALB2, RAD51C, RAD51D, EMSY, ATR, CHEK1, and FAM175A. Overall, 38 patients had mutations in BRCA1/2, 36 in other HRR genes, and 56 were negative for HRR mutations. All cases were re-reviewed and quantified by two genitourinary pathologists blinded to mutational status for the following histological patterns of prostate carcinoma: cribriform, ductal, intraductal carcinoma (IDC), small cell carcinoma, signet ring-like pattern, and lobular carcinoma-like pattern. Discordances were resolved by consensus review. Histologic patterns were analyzed for any correlation with mutations in HRR pathway genes (grouped as BRCA1/2 mutated or non-BRCA1/2 mutated) compared to tumors without mutations in HRR genes by Chi-square testing. Patterns with >20 % and >30 % of tumor volume were additionally evaluated for correlation with mutational status. We found no significant association between HRR pathway mutations and cribriform pattern, IDC, ductal carcinoma, small cell carcinoma, signet ring-like pattern, or lobular carcinoma-like patterns. Tumors with >20 % or >30 % histologic patterns by volume also demonstrated no significant association with mutational status. This study suggests that histopathologic examination alone is insufficient to distinguish prostate cancer with germline or somatic mutations in HRR pathway genes, highlighting the continuing importance of ancillary molecular diagnostics in guiding therapy selection for prostate cancer patients who may benefit from PARP inhibitors.

Bispecific T-cell Engagers in Metastatic Castration-Resistant Prostate Cancer.

SUMMARY: To date, immune targeting agents have provided limited benefits in patients with metastatic prostate cancer. Bispecific T-cell engagers, especially targeting STEAP1, have shown encouraging results in preclinical and phase I studies and thus represent a novel and promising treatment option in this setting. See related article by Nolan-Stevaux et al., p. 90 (7). See related article by Kelly et al., p. 76 (8).

Outcomes of Patients with Brain Metastases from Renal Cell Carcinoma Receiving First-line Therapies: Results from the International Metastatic Renal Cell Carcinoma Database Consortium.

Patients with brain metastases (BrM) from renal cell carcinoma and their outcomes are not well characterized owing to frequent exclusion of this population from clinical trials. We analyzed data for patients with or without BrM using the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC). A total of 389/4799 patients (8.1%) had BrM on initiation of systemic therapy. First-line immuno-oncology (IO)-based combination therapy was associated with longer median overall survival (OS; 32.7 mo, 95% confidence interval [CI] 22.3-not reached) versus tyrosine kinase inhibitor monotherapy (20.6 mo, 95% CI 15.7-24.5; p = 0.019), as were intensive focal therapies with stereotactic radiotherapy or neurosurgery (31.4 mo, 95% CI 22.3-37.5) versus whole-brain radiotherapy alone or no focal therapy (16.5 mo, 95% CI 10.2-21.1; p = 0.028). On multivariable analysis, IO-based regimens (HR 0.49, 95% CI 0.25-0.97; p = 0.040) and stereotactic radiotherapy or neurosurgery (HR 0.48, 95% CI 0.29-0.78; p = 0.003) were independently associated with longer OS, as was IMDC favorable or intermediate risk (HR 0.40, 95% CI 0.24-0.66; p < 0.001). Intensive systemic and focal therapies were associated with better prognosis in this population. Further studies should explore the clinical effectiveness of multimodal strategies. PATIENT SUMMARY: In a large group of patients with advanced kidney cancer, we found that 8.1% had brain metastases when starting systemic therapy. Patients with brain metastases had significantly poorer prognosis than those without brain metastases. Receipt of combination immunotherapy, stereotactic radiotherapy, or neurosurgery was associated with longer overall survival.

Impact of Initial Timing of Metastatic Disease on Survival in Patients With Newly Diagnosed Metastatic Castration-Resistant Prostate Cancer Treated With Androgen Receptor Pathway Inhibitors.

INTRODUCTION: Patients with synchronous (de novo) metastatic castration-sensitive prostate cancer appear to have worse survival outcomes and shorter time to develop castration resistance than patients with metachronous disease. However, the impact of synchronous metastasis on outcomes in metastatic castration-resistant prostate cancer (mCRPC) setting is unknown in patients without prior exposure to androgen receptor pathway inhibitors (ARPIs). In this study, we assessed the impact of initial timing of metastasis (synchronous vs metachronous) on survival outcomes of patients with new-onset mCRPC in a real-world population treated with first-line abiraterone or enzalutamide. METHODS: Data were collected retrospectively from 323 patients with a confirmed diagnosis of mCRPC who received ARPIs as first-line therapy and had no prior exposure to ARPIs. The study endpoints were progression-free survival and overall survival. RESULTS: The results showed that median overall survival was significantly shorter in patients with synchronous disease than those with metachronous disease (26 vs 38.7 months, HR 1.42, 95% CI 1.09-1.86, P = .011). However, there was no difference in median progression-free survival. CONCLUSIONS: The initial presentation with synchronous metastasis remained an independent factor associated with shorter OS in the multivariable analysis. These hypothesis-generating data, after external validation, may have implications in patient counseling, prognostication, and design of future clinical trials in the new-onset mCRPC setting.

Predictors of response to neoadjuvant therapy in urothelial cancer.

Neoadjuvant cisplatin-based chemotherapy (NACC) followed by radical cystectomy is the standard treatment for localized muscle-invasive bladder cancer (MIBC). Patients who achieve a complete pathological response following NACC have better overall survival than those with residual disease. However, a subset of patients does not derive benefit from NACC while experiencing chemotherapy-related side effects that may delay cystectomy, which can be detrimental. There is a need for predictive and prognostic biomarkers to better stratify patients who will derive benefits from NACC. This review summarizes the currently available literature on various predictors of response to neoadjuvant chemotherapy. Covered predictors include clinical factors, treatment regimens (including chemotherapy and immunotherapy), histological predictors, and molecular predictors such as DNA repair genes, p53, FGFR3, ERBB2, Bcl-2, EMMPRIN, survivin, choline-phosphate cytidylyltransferase-α, epigenetic markers, immunological markers, other molecular predictors and gene expression profiling. Further, we elaborate on the potential role of neoadjuvant immunotherapy and the correlative biomarkers of response.

Case report: Primary cardiac lymphoma manifesting as superior vena cava syndrome.

A 64-year-old man presented with symptoms indicative of superior vena cava syndrome. Imaging work-up revealed an obstructing right atrial mass, which was subsequently excised and diagnosed as primary cardiac lymphoma. Post-surgery, the patient showed significant clinical improvement and was started on a chemotherapy regimen with complete remission at 1 year.

Race and Treatment Outcomes in Patients With Metastatic Castration-Sensitive Prostate Cancer: A Secondary Analysis of the SWOG 1216 Phase 3 Trial.

Importance: Black patients present with more aggressive disease and experience higher mortality than White patients with prostate cancer. Race and social determinants of health influence prostate cancer-specific mortality and overall survival (OS); however, in a previous trial, Black patients did not have inferior outcomes compared with White patients, possibly because of equitable access to care available in a clinical trial setting. Objective: To compare differences in survival outcomes of patients with metastatic castration-sensitive prostate cancer (mCSPC) by race in a phase 3 trial with a large proportion of Black patients. Design, Setting, and Participants: This secondary analysis of patient-level data of a prospective phase 3 randomized clinical trial included patients with newly diagnosed mCSPC enrolled between March 1, 2013, and July 15, 2017. Analysis was conducted between December 2022 and February 2023. Interventions: Patients receiving androgen deprivation therapy were randomized (1:1) to receive either orteronel 300 mg orally twice daily (experimental group) or bicalutamide 50 mg orally daily (control group). Main Outcomes and Measures: OS, with progression-free survival (PFS) as a secondary end point. Results: Among 1313 participants, 135 (10%) identified as Black and 1077 (82%) as White, with an equal racial distribution between groups. Black patients were younger (median [IQR] age, 65.8 [60-70] vs 68.4 [62.5-74.1] years; P = .001) and had a higher median (IQR) baseline prostate-specific antigen response rate than White patients (54.7 [19.8-222.0] vs 26.7 [9.2-96.0] ng/mL; P < .001). At a median follow-up of 4.9 years, Black and White patients had similar median PFS (2.3 years; 95% CI, 1.8-1.4 years vs 2.9 years; 95% CI, 2.5-3.3 years; P = .71) and OS (5.5 years; 95% CI, 4.8-NR vs 6.3 years; 95% CI, 5.7-NR; P = .65). The multivariable analysis confirmed similar PFS and OS after adjusting for known prognostic factors. No interaction between race and treatment was observed. Conclusions and Relevance: In this secondary analysis of a randomized clinical trial studying androgen deprivation therapy with first- or second-generation androgen receptor pathway inhibitors, both Black and White patients demonstrated similar OS and PFS. Equitable access to care may reduce historical differences in outcomes between Black and White patients with advanced prostate cancer. Trial Registration: ClinicalTrials.gov Identifier: NCT01809691.

Impact of androgen receptor alterations on cell-free DNA genomic profiling on survival outcomes in metastatic castration-resistant prostate cancer.

BACKGROUND: Androgen receptor (AR) gene alterations, as detected by circulating tumor cell-free DNA (cfDNA) genomic profiling, have been shown to emerge after a variable duration of androgen signaling inhibition. AR alterations were associated with inferior outcomes on treatment with androgen receptor pathway inhibitors (ARPI) in the first line metastatic castration-resistant prostate cancer (mCRPC) setting in a phase 2 trial. Here in, we assessed the impact of these AR alterations on survival outcomes in a real-world patient population of mCRPC experiencing disease progression on an ARPI. METHODS: In this IRB-approved retrospective study, consecutively seen patients with a confirmed diagnosis of mCRPC, with disease progression on a treatment with ARPIs in the first line mCRPC setting, with no prior exposure to an ARPI in the castration sensitive setting, and with available cfDNA profiling from a CLIA certified laboratory were included. Patients were categorized based on AR status: wild-type (ARwt ) or alteration-positive (AR+ ). The objective was to correlate overall survival (OS) after disease progression on the first-line ARPI with the presence or absence of AR alterations. Kaplan-Meier and Cox Regression Tests were used as implemented in R-Studio (v.4.2). RESULTS: A total of 137 mCRPC patients were eligible: 69 with ARwt versus 68 with AR+ . The median OS posttreatment with the first ARPI was significantly higher for ARwt than AR+ patients (30.1 vs. 15.2 mos; p < 0.001). Of 108 patients who received a subsequent line of therapy, 63 received an alternate ARPI (AR+ 39 vs. 24 ARwt ), while 20 received a taxane-based therapy (11 AR+ vs. 9 ARwt ). Among patients receiving an alternate ARPI, AR+ had numerically shorter OS (16.8 vs. 30.4 mos, p = 0.1). Among patients receiving taxane-based regimens, the OS was not significantly different between AR+ and ARwt (14.5 vs. 10.1 mos, p = 0.18). CONCLUSION: In this real-world study, mCRPC patients with AR alterations on cfDNA had inferior OS after disease progression on the first ARPI, compared to those who did not, and may impact outcomes on a subsequent ARPI but not on subsequent taxane-based therapy received. By providing survival estimates for patients with or without AR alterations, our data may aid in patient counseling, prognostication, treatment decision, and for designing future clinical trials in this setting.