Cumulative cancer locations on prostate biopsy and active surveillance outcomes in the MRI era

BACKGROUND

To validate the use of a cumulative cancer locations (CCLO) score, a measurement of tumor volume on biopsy, and to develop a novel magnetic resonance imaging (MRI)-informed CCLO (mCCLO) score to predict clinical outcomes on active surveillance (AS).

METHODS

The CCLO score is a sum of uniquely involved sextants with prostate cancer on diagnostic + confirmatory biopsy. The mCCLO score incorporates MRI findings into the CCLO score. Participants included 1284 individuals enrolled on AS between 1994 and 2022, 343 of whom underwent prostate MRI. The primary outcome was grade reclassification (GR) to grade group ≥2 disease; the secondary outcome was receipt of definitive treatment.

RESULTS

Increasing CCLO and mCCLO risk groups were associated with higher risk of GR and undergoing definitive treatment (both p < 0.001). On multivariable analysis, increasing mCCLO score was associated with higher risk of GR and receipt of definitive treatment (hazard ratios [HRs] per 1-unit increase: 1.26 [95% confidence interval [CI]: 1.12-1.41] and 1.21 [95% CI: 1.07-1.36], respectively). The model using mCCLO score to predict GR (c-index: 0.671; 95% CI: 0.621-0.721) performed at least as well as models using the number of cores positive for cancer (0.664 [0.613-0.715]; p = 0.7) and the maximum percentage of cancer in a core (0.641 [0.585-0.696]; p = 0.14).

CONCLUSIONS

The CCLO score is a valid, objective metric to predict GR and receipt of treatment in a large AS cohort. The ability of the MRI-informed mCCLO to predict GR is on par with traditional metrics of tumor volume but is more descriptive and may benefit from greater reproducibility. The mCCLO score can be implemented as a shorthand, informative tool for counseling patients about whether to remain on AS.

Retrospective Multicenter Observational Study of Immediate Voiding at End of Urinary Sphincter Surgery (REMOVE)

PURPOSE

Patients may remain catheterized after artificial urinary sphincter surgery to prevent urinary retention, despite a lack of evidence to support this practice. Our study aims to evaluate the feasibility of outpatient, catheter-free continence surgery using a multi-institutional database. We hypothesize that between catheterized controls and patients without a catheter, there would be no difference in the rate of urinary retention or postoperative complications.

MATERIALS AND METHODS

We conducted a retrospective review of patients undergoing first-time artificial urinary sphincter placement from 2009-2021. Patients were stratified by postoperative catheter status into either no-catheter (leaving the procedure without a catheter) or catheter (postoperative indwelling catheter for ∼24 hours). The primary outcome, urinary retention, was defined as catheterization due to subjective voiding difficulty or documented postvoid residual over 250 mL.

RESULTS

Our study identified 302 catheter and 123 no-catheter patients. Twenty (6.6%) catheter and 9 (7.3%) no-catheter patients developed urinary retention (P = .8). On multivariable analysis, controlling for age, cuff size, radiation history and surgeon, there was no statistically significant association between omitting a catheter and urinary retention (OR: 0.45, 95% CI: 0.13-1.58; P = .2). Furthermore, at 30 months follow-up, Kaplan-Meier survival analysis revealed that device survival was 70% (95% CI: 62%-76%) vs 69% (95% CI: 48%-82%) for the catheter and no-catheter group, respectively.

CONCLUSIONS

In our multi-institutional cohort, overall retention rates were low (7%) in groups with a catheter and without. Obviating postoperative catheterization facilitates outpatient incontinence surgery without altering reoperation over medium-term follow-up.

Abstract P6-08-07: Reasons for Reduced Willingness to Participate in Clinical Trials During the COVID-19 Pandemic: The Translational Breast Cancer Research Consortium (TBCRC) 057 Survey

Background: Historically, less than 10% of adult patients with cancer enroll in clinical trials, however, enrollment dropped further at the onset of the COVID-19 pandemic. Barriers to trial participation during the pandemic have not been reported. As part of the TBCRC 057 survey on the impact of the pandemic on willingness to participate in breast cancer trials, we assessed reasons for reluctance to participate in trials during the pandemic.

Methods: US residents who self-reported a breast cancer diagnosis were eligible to complete the online survey 8/6/21-9/30/21. Respondents indicated whether they were current trial participants and, if not, their willingness to consider participating in a trial during the pandemic using a 5-point scale (0-not at all willing to 4-definitely willing). Respondents who were not current trial participants and who were not “definitely willing” to consider participation during the pandemic were characterized as “reluctant” and asked to select reasons for their reluctance from a checklist. Pandemic-related anxiety was assessed on an 11-point scale (0-no anxiety to 10-worst anxiety possible). Respondents indicated how the option to conduct trial activities online would affect their decision to participate in a trial (much less likely, somewhat less likely, would not affect my decision, somewhat more likely, or much more likely). In exploratory analyses, we evaluated whether pandemic-related anxiety and favorable reactions towards opportunities to conduct trial activities online were associated with reluctance to consider trial participation during the pandemic due to fear of SARS-CoV-2 exposure. Means were compared with two sample t-tests and proportions with Fisher’s exact tests.

Results: Of 385 survey respondents, 185 (48%) were characterized as reluctant to consider trial participation during the pandemic. Among these 185, median age was 55 (range 25-80), 85.7% were non-Hispanic White, 48.1% had metastatic disease and 44.2% received care at academic centers. Reasons for reluctance to consider trial participation during the pandemic cited by ≥15% of the 185 reluctant respondents are shown in the Table. Respondents who selected fear of exposure to SARS-CoV-2 as a reason for their reluctance to consider participating in a trial during the pandemic had higher mean pandemic-related anxiety (7.0 vs 5.2, p&lt; 0.001). These respondents were more likely to indicate telemedicine doctor visits (p=0.01), virtual consents (p=0.001) and online study questionnaires (p=0.001) would make them somewhat or much more likely to participate in trials than respondents who did not select fear of exposure to SARS-CoV-2 as a reason for their reluctance.

Conclusions: Reasons for reluctance of patients with breast cancer to consider participation in clinical trials during the pandemic are multifactorial. Although concerns about safety and efficacy remain prominent, fear of exposure to SARS-CoV-2 drives unwillingness to participate in &gt;25% of reluctant patients. Trial accrual may benefit from incorporation of electronic activities when possible.

Table

Citation Format: Karen L. Smith, Carolyn Mead-Harvey, Gina L. Mazza, Albert E. Holler, Eileen Shinn, Elizabeth Frank, Michelle Melisko, Cyd Eaton, Jeannine M. Salamone, Teri Pollastro, Patricia Spears, Antonio C. Wolff, Gabrielle B. Rocque. Reasons for Reduced Willingness to Participate in Clinical Trials During the COVID-19 Pandemic: The Translational Breast Cancer Research Consortium (TBCRC) 057 Survey [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P6-08-07.

Assessing COVID-19 Health Information on Google Using the Quality Evaluation Scoring Tool (QUEST): Cross-sectional and Readability Analysis

BACKGROUND

The COVID-19 pandemic spurred an increase in online information regarding disease spread and symptomatology.

OBJECTIVE

Our purpose is to systematically assess the quality and readability of articles resulting from frequently Google-searched COVID-19 terms in the United States.

METHODS

We used Google Trends to determine the 25 most commonly searched health-related phrases between February 29 and April 30, 2020. The first 30 search results for each term were collected, and articles were analyzed using the Quality Evaluation Scoring Tool (QUEST). Three raters scored each article in authorship, attribution, conflict of interest, currency, complementarity, and tone. A readability analysis was conducted.

RESULTS

Exactly 709 articles were screened, and 195 fulfilled inclusion criteria. The mean article score was 18.4 (SD 2.6) of 28, with 7% (14/189) scoring in the top quartile. National news outlets published the largest share (70/189, 36%) of articles. Peer-reviewed journals attained the highest average QUEST score compared to national/regional news outlets, national/state government sites, and global health organizations (all P<.05). The average reading level was 11.7 (SD 1.9, range 5.4-16.9). Only 3 (1.6%) articles were written at the recommended sixth grade level.

CONCLUSIONS

COVID-19-related articles are vastly varied in their attributes and levels of bias, and would benefit from revisions for increased readability.

Differential Activity of PARP Inhibitors in BRCA1- Versus BRCA2-Altered Metastatic Castration-Resistant Prostate Cancer

Two poly (ADP-ribose) polymerase (PARP) inhibitors (olaparib and rucaparib) are US Food and Drug Administration-approved for patients with metastatic castration-resistant prostate cancer (mCRPC) harboring BRCA1/2 mutations, but the relative efficacy of PARP inhibition in BRCA1- versus BRCA2-altered mCRPC is understudied.

METHODS

We conducted a multicenter retrospective analysis involving 12 sites. We collected genomic and clinical data from 123 patients with BRCA1/2-altered mCRPC who were treated with PARP inhibitors. The primary efficacy end point was the prostate-specific antigen (PSA) response (≥ 50% PSA decline) rate. Secondary end points were PSA progression-free survival (PSA-PFS), clinical or radiographic PFS, and overall survival. We compared clinical outcomes, and other genomic characteristics, among BRCA1- versus BRCA2-altered mCRPC.

RESULTS

A total of 123 patients (13 BRCA1 and 110 BRCA2) were included. PARP inhibitors used were olaparib (n = 116), rucaparib (n = 3), talazoparib (n = 2), and veliparib (n = 2). At diagnosis, 72% of patients had Gleason 8-10 disease. BRCA1 patients were more likely to have metastatic disease at presentation (69% v 37%; P = .04). Age, baseline PSA, metastatic distribution, and types of previous systemic therapies were similar between groups. There were equal proportions of germline mutations (51% v 46%; P = .78) in both groups. BRCA1 patients had more monoallelic (56% v 41%; P = .49) and concurrent TP53 (55% v 36%; P = .32) mutations. PSA₅₀ responses in BRCA1- versus BRCA2-altered patients were 23% versus 63%, respectively (P = .01). BRCA2 patients achieved longer PSA-PFS (HR, 1.94; 95% CI, 0.92 to 4.09; P = .08), PFS (HR, 2.08; 95% CI, 0.99 to 4.40; P = .05), and overall survival (HR, 3.01; 95% CI, 1.32 to 6.83; P = .008). Biallelic (compared with monoallelic) mutations, truncating (compared with missense) mutations, and absence of a concurrent TP53 mutation were associated with PARP inhibitor sensitivity.

CONCLUSION

PARP inhibitor efficacy is diminished in BRCA1- versus BRCA2-altered mCRPC. This is not due to an imbalance in germline mutations but might be related to more monoallelic mutations and/or concurrent TP53 alterations in the BRCA1 group.

Clonal hematopoiesis in prostate cancer inferred from somatic tumor profiling

e17001

Background: Clonal hematopoiesis (CH) is a process associated with normal aging and may complicate the interpretation of liquid-biopsy genomic testing in oncology. Little is known about the prevalence of CH in prostate cancer as detected on somatic tumor profiling, or its association with clinical parameters and outcomes in prostate cancer. We sought to estimate the prevalence and clinical characteristics of patients with CH identified from tissue-based prostate cancer specimens. Methods: This was a retrospective study of men with prostate adenocarcinoma who underwent clinical somatic tissue-based next-generation sequencing using commercial platforms (n = 364). Patients with known hematologic malignancies (n = 7), and those with only liquid biopsies were excluded (n = 34), leaving 323 cases. Classical CH mutations were defined as those in DNMT3A, TET2 or ASXL1. Additional CH mutations included were defined as those in BCORL1, GNAS, SF3B1, JAK2 or PPM1D. Chi-squared tests were used to compare prevalence by categorical variables, Kruskal-Wallis tests to compare means across groups, and Cox proportional hazards were used for time-to-event analyses. Results: The prevalence of CH mutations in prostate cancer was 9% (30/323), and the prevalence of classical CH mutations was 7% (22/323)(Table). The most common mutations were in DNMT3A (n = 9), TET2 (n = 8) and ASXL1 (n = 5); other less common CH alterations were in GNAS and SF3B1 (n = 3 each), followed by CBL and JAK2 (n = 1 each). The most common site of tumor biopsy was the prostate (N = 266) followed by visceral (n = 19) and lymph node (N = 19) metastases. Men with any CH mutation were not significantly older at age of prostate cancer diagnosis (64 vs 62 years; p = 0.19) than those without; however, men with classical CH mutations were statistically older at diagnosis than those without (66 vs 62 years; p = 0.04). There was no difference in prevalence of CH mutations by Gleason sum (P = 0.67). Among men with localized disease at diagnosis, the median metastasis-free survival was 3.9 years in those with overall CH mutations and 6.6 years in those without CH mutations (HR [adjusted for age and Gleason] 1.3; 95% CI 0.7-2.3; p = 0.4). OS from the time of diagnosis to death was also numerically shorter in those with any CH mutation (median 9.7 years in those with and 14.2 years in those without CH mutations; HR 1.2, 95% CI 0.6-2.5; p = 0.6). Conclusions: CH can be detected in about 7-9% of prostate cancer patients from tissue-based tumor samples, is associated with older age, and may be linked to adverse oncological outcomes. The prognostic impact of CH in the context of specific systemic therapies (hormonal, chemotherapeutic) remains to be elucidated.[Table: see text]

Differential activity of PARP inhibitors in BRCA1- versus BRCA2-altered metastatic castration-resistant prostate cancer (mCRPC)

100

Background: Two PARP inhibitors (olaparib, rucaparib) are now FDA approved for mCRPC patients with mutations in BRCA1/2, but the relative efficacy of PARP inhibition in BRCA1- vs BRCA2-altered mCRPC is understudied. Methods: We conducted a multi-center retrospective analysis involving 11 academic sites. We collected genomic and clinical data from 123 BRCA1/2-altered mCRPC patients receiving PARP inhibitor treatment. The primary efficacy endpoint was PSA50 response rate (≥50% decline in PSA level). Secondary endpoints were PFS (clinical, radiographic or PSA progression, whichever occurred first) and overall survival (OS). We also captured information on other concurrent genomic alterations. We compared genomic characteristics and clinical outcomes among BRCA1- vs BRCA2-altered mCRPC. Results: A total of 123 patients (13 BRCA1, 110 BRCA2) were included. PARP inhibitors used were olaparib (n = 116), rucaparib (n = 3), talazoparib (n = 2) and veliparib (n = 2). All BRCA1 and 71% of BRCA2 patients had Gleason 8-10 disease. Compared to BRCA2 patients, BRCA1 patients were more likely to have received prior taxane chemotherapy (77% vs 62%). Age, baseline PSA, and prior enzalutamide/abiraterone treatment were similar between groups. PSA50 responses in BRCA1- vs BRCA2-altered patients were 38% vs 65% respectively ( P= 0.06). Median PFS in BRCA1 vs BRCA2 patients was 3.0 mo (95%CI, 0.9–5.1) vs 8.0 mo (95%CI, 5.3–10.6) respectively (HR 0.42, P= 0.01). Similarly, median OS in BRCA1 vs BRCA2 patients was 11.0 mo (95%CI, 9.9–12.1) vs 24.0 mo (95%CI, 18.2–29.8) respectively (HR 0.33, P= 0.005). There were roughly equal proportions of germline mutations (50% vs 45%) and biallelic mutations (31% vs 25%) in the BRCA2 and BRCA1 groups, respectively. There were numerically more TP53 mutations in the BRCA1 vs BRCA2 group (40% vs 29%, P= 0.45), but an equal number of mutations in other key genes ( PTEN, RB1 and AR). Conclusions: PARP inhibitor activity is diminished in BRCA1- vs BRCA2-altered mCRPC. In our cohort, this differential activity was not explained by mutation origin (germline vs somatic) or allelic status (mono- vs biallelic). These findings warrant validation.

Targeting the IGF1R/PI3K/AKT Pathway Sensitizes Ewing Sarcoma to BET Bromodomain Inhibitors

Inhibitors of the bromodomain and extra-terminal domain (BET) family proteins modulate EWS-FLI1 activities in Ewing sarcoma. However, the efficacy of BET inhibitors as a monotherapy was moderate and transient in preclinical models. The objective of this study was to identify the mechanisms mediating intrinsic resistance to BET inhibitors and develop more effective combination treatments for Ewing sarcoma. Using a panel of Ewing sarcoma cell lines and patient-derived xenograft lines (PDX), we demonstrated that IGF1R inhibitors synergistically increased sensitivities to BET inhibitors and induced potent apoptosis when combined with BET inhibitors. Constitutively activated AKT significantly protected Ewing sarcoma cells against BET inhibitors, suggesting that IGF1R regulates responsiveness to BET inhibitors mainly through the PI3K/AKT pathway. Although two Ewing sarcoma cell lines were resistant to IGF1R inhibitors, they retained synergistic response to a combination of BET inhibitors and mTOR inhibitors, suggesting that BET proteins, when IGF1R is not functional, cross-talk with its downstream molecules. Furthermore, the combination of a BET inhibitor and an IGF1R inhibitor induced potent and durable response in xenograft tumors, whereas either agent alone was less effective. Taken together, our results suggest that IGF1R and the downstream PI3K/AKT/mTOR kinase cascade mediate intrinsic resistance to BET inhibitors in Ewing sarcoma. These results provide the proof-of-concept for combining BET inhibitors with agents targeting the IGF1R pathway for treating advanced Ewing sarcoma.