Unpacking overuse of androgen deprivation therapy for prostate cancer to inform de-implementation strategies

BACKGROUND

Many men with prostate cancer will be exposed to androgen deprivation therapy (ADT). While evidence-based ADT use is common, ADT is also used in cases with no or limited evidence resulting in more harm than benefit, i.e., overuse. Since there are risks of ADT (e.g., diabetes, osteoporosis), it is important to understand the behaviors facilitating overuse to inform de-implementation strategies. For these reasons, we conducted a theory-informed survey study, including a discrete choice experiment (DCE), to better understand ADT overuse and provider preferences for mitigating overuse.

METHODS

Our survey used the Action, Actor, Context, Target, Time (AACTT) framework, the Theoretical Domains Framework (TDF), the Capability, Opportunity, Motivation-Behavior (COM-B) Model, and a DCE to elicit provider de-implementation strategy preferences. We surveyed the Society of Government Service Urologists listserv in December 2020. We stratified respondents based on the likelihood of stopping overuse as ADT monotherapy for localized prostate cancer ("yes"/"probably yes," "probably no"/"no"), and characterized corresponding Likert scale responses to seven COM-B statements. We used multivariable regression to identify associations between stopping ADT overuse and COM-B responses.

RESULTS

Our survey was completed by 84 respondents (13% response rate), with 27% indicating "probably no"/"no" to stopping ADT overuse. We found differences across respondents who said they would and would not stop ADT overuse in demographics and COM-B statements. Our model identified 2 COM-B domains (Opportunity-Social, Motivation-Reflective) significantly associated with a lower likelihood of stopping ADT overuse. Our DCE demonstrated in-person communication, multidisciplinary review, and medical record documentation may be effective in reducing ADT overuse.

CONCLUSIONS

Our study used a behavioral theory-informed survey, including a DCE, to identify behaviors and context underpinning ADT overuse. Specifying behaviors supporting and gathering provider preferences in addressing ADT overuse requires a stepwise, stakeholder-engaged approach to support evidence-based cancer care. From this work, we are pursuing targeted improvement strategies.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03579680.

Understanding the Role of Urology Practice Organization and Racial Composition in Prostate Cancer Treatment Disparities

PURPOSE

Black men have a higher risk of prostate cancer diagnosis and mortality but are less likely to receive definitive treatment. The impact of structural aspects on treatment is unknown but may lead to actionable insights to mitigate disparities. We sought to examine the associations between urology practice organization and racial composition and treatment patterns for Medicare beneficiaries with incident prostate cancer.

METHODS

Using a 20% sample of national Medicare data, we identified beneficiaries diagnosed with prostate cancer between January 2010 and December 2015 and followed them through 2016. We linked urologists to their practices with tax identification numbers. We then linked patients to practices on the basis of their primary urologist. We grouped practices into quartiles on the basis of their proportion of Black patients. We used multilevel mixed-effects models to identify treatment associations.

RESULTS

We identified 54,443 patients with incident prostate cancer associated with 4,194 practices. Most patients were White (87%), and 9% were Black. We found wide variation in racial practice composition and practice segregation. Patients in practices with the highest proportion of Black patients had the lowest socioeconomic status (43.1%), highest comorbidity (9.9% with comorbidity score ≥ 3), and earlier age at prostate cancer diagnosis (33.5% age 66-69 years; P < .01). Black patients had lower odds of definitive therapy (adjusted odds ratio, 0.87; 95% CI, 0.81 to 0.93) and underwent less treatment than White patients in every practice context. Black patients in practices with higher proportions of Black patients had higher treatment rates than Black patients in practices with lower proportions. Black patients had lower predicted probability of treatment (66%) than White patients (69%; P < .05).

CONCLUSION

Despite Medicare coverage, we found less definitive treatment among Black beneficiaries consistent with ongoing prostate cancer treatment disparities. Our findings are reflective of the adverse effects of practice segregation and structural racism, highlighting the need for multilevel interventions.

Learning from the "tail end" of de-implementation: the case of chemical castration for localized prostate cancer

BACKGROUND

Men with prostate cancer are often treated with the suppression of testosterone through long-acting injectable drugs termed chemical castration or androgen deprivation therapy (ADT). In most cases, ADT is not an appropriate treatment for localized prostate cancer, indicating low-value care. Guided by the Theoretical Domains Framework (TDF) and the Behavior Change Wheel's Capability, Opportunity, Motivation Model (COM-B), we conducted a qualitative study to identify behavioral determinants of low-value ADT use to manage localized prostate cancer, and theory-based opportunities for de-implementation strategy development.

METHODS

We used national cancer registry and administrative data from 2016 to 2017 to examine the variation in low-value ADT use across Veterans Health Administration facilities. Using purposive sampling, we selected high- and low-performing sites to conduct 20 urology provider interviews regarding low-value ADT. We coded transcripts into TDF domains and mapped content to the COM-B model to generate a conceptual framework for addressing low-value ADT practices.

RESULTS

Our interview findings reflected provider perspectives on prescribing ADT as low-value localized prostate cancer treatment, including barriers and facilitators to de-implementing low-value ADT. We characterized providers as belonging in 1 of 3 categories with respect to low-value ADT use: 1) never prescribe 2); willing, under some circumstances, to prescribe: and 3) prescribe as an acceptable treatment option. Provider capability to prescribe low-value ADT depended on their knowledge of localized prostate cancer treatment options (knowledge) coupled with interpersonal skills to engage patients in educational discussion (skills). Provider opportunity to prescribe low-value ADT centered on the environmental resources to inform ADT decisions (e.g., multi-disciplinary review), perceived guideline availability, and social roles and influences regarding ADT practices, such as prior training. Provider motivation involved goals of ADT use, including patient preferences, beliefs in capabilities/professional confidence, and beliefs about the consequences of prescribing or not prescribing ADT.

CONCLUSIONS

Use of the TDF domains and the COM-B model enabled us to conceptualize provider behavior with respect to low-value ADT use and clarify possible areas for intervention to effect de-implementation of low-value ADT prescribing in localized prostate cancer.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT03579680.

Impact of Medicare Office Visit Payment Reform on Urologic Practices

OBJECTIVE

To evaluate the 2019 Medicare Physician Fee Schedule, which modifies reimbursement for office evaluation and management (E&M) visits. This policy moves payment to a single rate for levels 2 through 4 office E&M visits, regardless of complexity.

METHODS

Using a 20% sample of 2015 National Medicare claims, we identified urologic practices and their practice organization, academic affiliation, and degree of office focus (ie, proportion of revenues from office visits). Using billing data for each practice, we calculated the revenues expected under the current system and the new policy (both E&M payments and a new add-on code). For each practice, we determined the impact of new payment rates on total Medicare payments.

RESULTS

We identified 2822 practices: 1372 (48.6%) solo practices, 1033 (36.6%) multispecialty groups, 322 (11.4%) small urology groups, and 95 (3.4%) large urology groups. Under the new reimbursement rates, the median practice would have a 0.9% increase in Medicare Part B payments (range -20.4% to +50.3%) and, with the add-on code, an increase of 6.8% (range -7.5% to +74.9%). Solo practices had the most heterogeneity, with a quarter losing at least 2.3%. The median multispecialty group would increase payments by 0.4% (range -13.7% to 50.3%). However, the 107 (10.4%) academic multispecialty groups had a median gain of only 0.1% (range -2.8% to +8.1%).

CONCLUSION

Urology groups would, on average, benefit from the anticipated change in Medicare office E&M visit payments. However, solo practices with a high office focus and academic multispecialty practices may see reduced Medicare payments.

Targeting Androgen Receptor and DNA Repair in Metastatic Castration-Resistant Prostate Cancer: Results From NCI 9012

Purpose To determine whether cotargeting poly (ADP-ribose) polymerase-1 plus androgen receptor is superior to androgen receptor inhibition in metastatic castration-resistant prostate cancer (mCRPC) and whether ETS fusions predict response. Patients and Methods Patients underwent metastatic site biopsy and were stratified by ETS status and randomly assigned to abiraterone plus prednisone without (arm A) or with veliparib (arm B). Primary objectives were: confirmed prostate-specific antigen (PSA) response rate (RR) and whether ETS fusions predicted response. Secondary objectives were: safety, measurable disease RR (mRR), progression-free survival (PFS), and molecular biomarker analysis. A total of 148 patients were randomly assigned to detect a 20% PSA RR improvement. Results A total of 148 patients with mCRPC were randomly assigned: arm A, n = 72; arm B, n = 76. There were no differences in PSA RR (63.9% v 72.4%; P = .27), mRR (45.0% v 52.2%; P = .51), or median PFS (10.1 v 11 months; P = .99). ETS fusions did not predict response. Exploratory analysis of tumor sequencing (80 patients) revealed: 41 patients (51%) were ETS positive, 20 (25%) had DNA-damage repair defect (DRD), 41 (51%) had AR amplification or copy gain, 34 (43%) had PTEN mutation, 33 (41%) had TP53 mutation, 39 (49%) had PIK3CA pathway activation, and 12 (15%) had WNT pathway alteration. Patients with DRD had significantly higher PSA RR (90% v 56.7%; P = .007) and mRR (87.5% v 38.6%; P = .001), PSA decline ≥ 90% (75% v 25%; P = .001), and longer median PFS (14.5 v 8.1 months; P = .025) versus those with wild-type tumors. Median PFS was longer in patients with normal PTEN (13.5 v 6.7 months; P = .02), TP53 (13.5 v 7.7 months; P = .01), and PIK3CA (13.8 v 8.3 months; P = .03) versus those with mutation or activation. In multivariable analysis adjusting for clinical covariates, DRD association with PFS remained significant. Conclusion Veliparib and ETS status did not affect response. Exploratory analysis identified a novel DRD association with mCRPC outcomes.

Evidence for association of SNPs in ABCB1 and CBR3, but not RAC2, NCF4, SLC28A3 or TOP2B, with chronic cardiotoxicity in a cohort of breast cancer patients treated with anthracyclines

AIMS

Validation of associations for SNPs in RAC2, NCF4 and SLC28A3, identification of a novel association with a TOP2B SNP and screening 23 SNPs putatively relevant to anthracycline-induced cardiotoxicity.

PATIENTS & METHODS

A total of 166 breast cancer patients treated with doxorubicin underwent echocardiogram, including 19 cases with systolic dysfunction (ejection fraction <55%) and 147 controls. Four high priority SNPs were tested in the primary analysis, with appropriate statistical correction, and 23 additional SNPs were screened in an uncorrected secondary analysis.

RESULTS

Previously reported associations for RAC2, NCF4 and SLC28A3 could not be validated and a novel association with TOP2B was not discovered in this cohort (all p > 0.05), likely due to inadequate power. Two SNPs were identified in the uncorrected secondary analysis including a protective SNP in ABCB1 (3435C>T, p = 0.049) and a risk allele in CBR3 (V244M, p = 0.012).

CONCLUSION

The associations reported in prior publications and those discovered in this secondary analysis require further replication in independent cohorts.

Advanced or metastatic gastrointestinal stromal tumors: systemic treatment options

Gastrointestinal stromal tumor (GIST), the most common sarcoma arising in the gastrointestinal tract, typically expresses the tyrosine-kinase receptor, C-KIT, and contains activating mutation in the c-kit or platelet-derived growth factor receptor (pdgfr) gene. Recently, development of small molecules that inhibit the kinase activity of mutant C-KIT and PDGFR proteins has radically changed treatment and prognosis of patients diagnosed with advanced GIST as this molecularly "targeted" therapy has demonstrated remarkable high-level of activity in this disease.