Emerging racial disparities among Medicare beneficiaries and Veterans with metastatic castration-sensitive prostate cancer

BACKGROUND

Previous studies have shown that Black men receive worse prostate cancer care than White men. This has not been explored in metastatic castration-sensitive prostate cancer (mCSPC) in the current treatment era.

METHODS

We evaluated treatment intensification (TI) and overall survival (OS) in Medicare (2015-2018) and Veterans Health Administration (VHA; 2015-2019) patients with mCSPC, classifying first-line mCSPC treatment as androgen deprivation therapy (ADT) + novel hormonal therapy; ADT + docetaxel; ADT + first-generation nonsteroidal antiandrogen; or ADT alone.

RESULTS

We analyzed 2226 Black and 16,071 White Medicare, and 1020 Black and 2364 White VHA patients. TI was significantly lower for Black vs White Medicare patients overall (adjusted odds ratio [OR] 0.68; 95% confidence interval [CI] 0.58-0.81) and without Medicaid (adjusted OR 0.70; 95% CI 0.57-0.87). Medicaid patients had less TI irrespective of race. OS was worse for Black vs White Medicare patients overall (adjusted hazard ratio [HR] 1.20; 95% CI 1.09-1.31) and without Medicaid (adjusted HR 1.13; 95% CI 1.01-1.27). OS was worse in Medicaid vs without Medicaid, with no significant OS difference between races. TI was significantly lower for Black vs White VHA patients (adjusted OR 0.75; 95% CI 0.61-0.92), with no significant OS difference between races.

CONCLUSIONS

Guideline-recommended TI was low for all patients with mCSPC, with less TI in Black patients in both Medicare and the VHA. Black race was associated with worse OS in Medicare but not the VHA. Medicaid patients had less TI and worse OS than those without Medicaid, suggesting poverty and race are associated with care and outcomes.

Implications of Delayed Testosterone Recovery in Patients with Prostate Cancer

To assess the clinical impact of delayed testosterone recovery (TR) following the discontinuation of medical androgen deprivation therapy (ADT), a retrospective, longitudinal analysis was conducted in adult males with prostate cancer using the Optum® de-identified Electronic Health Record data set and Optum® Enriched Oncology Data (2010-2021). Of 3875 patients who initiated and discontinued ADT, 1553 received one or more testosterone-level tests within the 12 mo following discontinuation and were included in this study. These 1553 patients were categorized into two cohorts: 25% as TR (testosterone levels >280 ng/dl at any test within 12 mo following ADT discontinuation) and 75% as non-TR. At baseline, non-TR patients were older, had lower testosterone levels, and were more likely to have diabetes, hyperlipidemia, and hypertension, but less likely to have sexual dysfunction. After adjustment for baseline characteristics, the TR cohort had a lower risk of new-onset diabetes (hazard ratio [HR] 0.47; 95% confidence interval [CI] 0.27-0.79), trended toward a lower risk of new-onset depression (HR 0.58; 95% CI 0.33-1.02), and had a higher likelihood of seeking treatment for sexual dysfunction (HR 1.33; 95% CI 0.99-1.78) versus the non-TR cohort. These findings support monitoring testosterone levels after ADT discontinuation to manage potential long-term comorbidities in patients with prostate cancer.

Patient summary

This real-world analysis of males with prostate cancer who were treated with medical androgen deprivation therapy (ADT) found that most patients did not have their testosterone level checked in the 12 mo after stopping ADT. Of those who did, 75% did not achieve normal testosterone levels (>280 ng/dl), and these patients were more likely to experience new-onset diabetes than those who achieved normal testosterone levels. These results suggest that to ensure effective clinical decision-making, physicians should check patients' testosterone levels after stopping ADT.

A Combined Phase 0/2 "Trigger" Trial Evaluating Pamiparib or Olaparib with Concurrent Radiotherapy in Patients with Newly-Diagnosed or Recurrent Glioblastoma

PURPOSE/OBJECTIVE(S)

This study evaluates the pharmacokinetic (PK) and pharmacodynamic (PD) profiles and clinical efficacy of PARP1/2 selective inhibitors, pamiparib and olaparib, in newly-diagnosed or recurrent glioblastoma (GBM) patients in combination with radiotherapy (RT).

MATERIALS/METHODS

In this combined phase 0/2 trial presumed newly-diagnosed (Arm A) or recurrent (Arm B) GBM patients received 4 days of pamiparib (60 mg BID) prior to resection either 2-4 or 8-12 hours following the final dose. Arm C enrolled patients with recurrent GBM to 4 days of olaparib (200 mg BID) prior to resection. Enhancing and nonenhancing tumor tissue, cerebrospinal fluid (CSF) and plasma were collected. Total and unbound drug concentrations were measured using validated LC-MS/MS methods. A PK 'trigger', defined as unbound drug and gt; 5-fold biochemical IC 50 in nonenhancing tumor, determined eligibility for the therapeutic expansion phase 2. PARP inhibition was assessed via ex vivo radiation and quantification of PAR levels compared to non-radiated control. Newly-diagnosed MGMT unmethylated GBMs and recurrent GBMs exceeding the PK threshold were eligible for an expansion phase of pamiparib (Arms A and B) or olaparib (Arm C) with concurrent RT followed by maintenance pamiparib or olaparib. RT was 60 Gy in 30 fractions in newly-diagnosed patients and 40 Gy in 15 fractions in recurrent patients, delivered using volumetric-modulated arc therapy (VMAT).

RESULTS

A total of 38 patients (Arm A, n = 16; Arm B, n = 16; Arm C, n = 6) were enrolled in the initial phase 0 study. The mean unbound concentrations of pamiparib in nonenhancing tumor region for Arm A and Arm B were 167.3 nM and 109.4 nM respectively, and in Arm C the mean unbound concentration of olaparib was 5.2 nM. All patients in the pamiparib arms (n = 32/32) but only 1 of 6 patients in the olaparib Arm C exceeded the PK threshold. Radiation-induced PAR expression was 2.44-fold in untreated control vs 1.16 in Arm A (p<0.05), 0.85 in Arm B (p<0.01) and 1.11 in Arm C patients, respectively. In Arm A, 11 patients had unmethylated tumors, and of those, 7 patients enrolled in phase 2. In Arm B, 9 of the 16 clinically eligible patients with positive PK results were enrolled in phase 2. At a median follow-up of 8.4 months [range: 1.3-15.7 months], the median progression-free survival (PFS) was 5.4, 6.0, and 3.8 months for Arms A (n = 7), B (n = 9), and C (n = 1), respectively. Grade 3+ toxicities related to pamiparib occurred in 4 patients, with 2 adverse events resulting in treatment discontinuation. No grade 3+ toxicities were documented in the olaparib arm.

CONCLUSION

Pamiparib achieved pharmacologically-relevant concentrations in nonenhancing GBM tissue and suppressed induction of PAR levels ex vivo post-radiation. The majority of patients with MGMT-unmethylated GBM advanced to the phase 2 portion of the trial, and pamiparib was generally well-tolerated in these patients.

A Combined Phase 0/2 "Trigger" Trial of Niraparib in Combination with Radiation in Patients with Newly-Diagnosed Glioblastoma

PURPOSE/OBJECTIVE(S)

Poly ADP-ribose (PAR) polymerase (PARP) mediates DNA damage response. Niraparib is an investigational PARP1/2-selective inhibitor. We conducted a combined phase 0/2 study to evaluate niraparib pharmacokinetics (PK) and pharmacodynamics (PD) in patients with newly-diagnosed glioblastoma (GBM), graduating patients to a phase 2 study evaluating a therapeutic regimen of niraparib with concurrent conventionally-fractionated radiotherapy (RT) in O6-methylguanine methyltransferase (MGMT) unmethylated tumors exceeding a prespecified PK threshold in non-enhancing tumor.

MATERIALS/METHODS

Patients with presumed newly-diagnosed GBM were enrolled in a phase 0 study receiving 4 days of niraparib (300 or 200 mg QD) prior to planned resection 3-5 or 8-12 hours following the last dose. Tumor tissue (enhancing and non-enhancing regions), cerebrospinal fluid (CSF), and plasma were collected. Total and unbound niraparib concentrations were measured using validated LC-MS/MS methods. PARP inhibition was assessed by quantification of PAR induction after 10 Gy ex vivo irradiation in surgical tissue compared to non-irradiated control tissue. A PK 'trigger' determined eligibility for the therapeutic phase 2 expansion portion of the study. This was defined as unbound [niraparib] > 5-fold biochemical IC50 (i.e., 19 nM) in non-enhancing tumor. Patients with MGMT unmethylated tumors exceeding this PK threshold were eligible for expansion phase dosing of niraparib with concurrent RT followed by a maintenance phase of niraparib. Patients with MGMT methylated tumors were not eligible for the expansion phase and proceeded with temozolomide (TMZ) plus RT followed by maintenance TMZ. RT dose was 60 Gy in 30 fractions using volumetric-modulated arc therapy (VMAT).

RESULTS

All 29 patients enrolled in the phase 0 portion of the study met the PK threshold. In non-enhancing regions, the mean unbound concentration of niraparib was 258.2 nM. The suppression of PAR levels after ex vivo RT was observed in 79% of the patients (17/22). Sixteen patients had unmethylated tumors, and of those, 11 patients enrolled in phase 2. Five of the 6 initial patients enrolled in phase 2 experienced thrombocytopenia related to niraparib, and 3/5 cases were deemed serious and life-threatening. Consequently, starting dose in both phases was lowered to 200 mg, and no serious AEs were observed thereafter. At a median follow-up of 8.1 months [range: 6.0-12.9 months], 6-month PFS was 64% with 4 patients remaining on treatment and 5 patients ongoing survival follow-up.

CONCLUSION

Niraparib achieves pharmacologically-relevant concentrations in non-enhancing, newly-diagnosed GBM tissue in excess of any other studied PARP inhibitor. When delivered with concurrent RT, niraparib was well-tolerated, with low rates of grade 3+ toxicity. Initial clinical efficacy data are encouraging.

Prostate-specific antigen response and clinical progression-free survival in Black and White men with chemotherapy-naïve metastatic castration-resistant prostate cancer treated with enzalutamide in a real-world setting

BACKGROUND

In the United States, Black men have a higher incidence of prostate cancer (PC)-related mortality than men of other races. Several real-world studies in advanced PC suggest, however, that Black men respond better to novel hormonal therapies than White men. Data on treatment responses to enzalutamide by race are limited. We assessed real-world prostate-specific antigen (PSA) response and clinical progression-free survival (cPFS) of Black vs. White men with chemotherapy-naïve PC treated with enzalutamide.

METHODS

This retrospective cohort study included patients with PC who initiated enzalutamide treatment from 2014 to 2018 in the IntrinsiQ Specialty Solutions™ database, a collection of electronic medical records from community urology practices. Index date was the date of the first prescription for enzalutamide, used as a proxy for metastatic castration-resistant PC (mCRPC). Patients who had undergone chemotherapy and/or abiraterone therapy were excluded. Kaplan-Meier and Cox models adjusted for baseline characteristics were used to estimate PSA response and cPFS by race.

RESULTS

The study included 214 Black and 1332 White men with chemotherapy-naïve PC presumed to have mCRPC based on the enzalutamide indication during the study period. Black men were younger and had higher baseline median PSA levels than White men. Enzalutamide therapy duration, follow-up time, and number of post-index PSA tests were similar between races. In multivariable analyses, the risk of patients achieving a ≥ 50% PSA decline was similar, whereas a numerically higher trend of ≥90% PSA decline was observed in Black men (HR 1.23; 95% CI 0.93-1.62 [P = 0.14]). In the multivariable analysis, Black men had significantly better cPFS (HR 0.82; 95% CI 0.68-0.98 [P = 0.03]).

CONCLUSIONS

Black and White men with presumed chemotherapy-naïve mCRPC had similar PSA responses when treated with enzalutamide, but Black men had better cPFS than White men. Further research is warranted to validate these findings.

Patient (pt) perspective on fatigue and its management for advanced prostate cancer (PC) treated with androgen receptor inhibitors (ARIs)

100

Background: Fatigue is a common, multifaceted disease- and treatment (tx)-related symptom experienced by pts with advanced PC (aPC). Although fatigue of variable severity has been reported across clinical trials in pts with metastatic hormone-sensitive PC (also referred to as metastatic castration-sensitive PC [mCSPC]) and non-metastatic castration-resistant PC (nmCRPC) treated with ARIs, there is limited real-world insight from the pt’s perspective or guidance on the management of this symptom. This study assessed pts’ experience with fatigue and self-reported management strategies. Methods: In this cross-sectional non-interventional qualitative research study, pts receiving ARIs were interviewed about their fatigue experience and management strategies. All pts were ≥18 years, diagnosed with mCSPC or nmCRPC, currently on ARI tx (enzalutamide, apalutamide or darolutamide) that began ≤24 months (mo) prior to interview and experienced fatigue. Descriptive data extracted were organized into general concepts and presented as number and frequency of reports. Results: Among 143 screened pts, 11 completed the interview (mCSPC, 7; nmCRPC, 4). Most were White, mean age was 63 years and median time since ARI initiation was 12 mo. Pts described their fatigue experience as a physical, emotional or mental feeling that impacted activities of daily living. Pts attributed their fatigue to more than one cause including, but not limited to: a side effect of ARI tx, emotional burden of disease, or physical exertion. Most pts did not feel adequately prepared and indicated they would have liked to receive additional education or support to manage tx-related fatigue. As a result, most pts followed self-initiated management strategies such as healthy diet, rigorous exercise and increased rest, which were reported to be effective for some pts. Conclusions: Pts with aPC emphasized the lack of adequate knowledge and health care provider (HCP) recommendations for managing fatigue. Hence, there is a need to develop recommendations for fatigue management and resources to support HCPs’ counselling methods to ultimately improve pts’ quality of life while on tx. HCPs may play a critical role in developing and disseminating fatigue management initiatives. [Table: see text]

The Role of Physician Specialty in the Underutilization of Standard-of-Care Treatment Intensification in Patients With Metastatic Castration-sensitive Prostate Cancer

PURPOSE

We evaluate utilization of treatment intensification of androgen deprivation therapy with androgen receptor pathway inhibitor/docetaxel for metastatic castration-sensitive prostate cancer patients across physician specialties.

MATERIALS AND METHODS

This retrospective study identified patients with metastatic castration-sensitive prostate cancer in the Optum Research Database between 2014 and 2019. Adult men with ≥1 claim for metastatic disease within 90 days before or any time after the first prostate cancer claim who received androgen deprivation therapy were included. Physician specialty, determined from medical/pharmacy claims during each line of therapy, was categorized as urologist only, oncologist only, both (urologists and oncologists), or other (other specialties). Treatment intensification and patient characteristics were analyzed descriptively.

RESULTS

Of 4,675 patients, 16% were treated by urologists only, 20% by oncologists only, 63% by both, and 1.1% by others. Most frequent first line of therapy was androgen deprivation therapy ± first-generation nonsteroidal antiandrogens (>50%). Androgen deprivation therapy + docetaxel use declined over time, while androgen deprivation therapy + androgen receptor pathway inhibitor increased. Patients seen by oncologists or both were younger, had fewer comorbidities, and were likelier to receive treatment intensification compared to those treated by urologists. By 2019, however, treatment intensification remained <40% from oncologists only or both, and <15% from urologists only. In the second and third lines of therapy, androgen deprivation therapy + androgen receptor pathway inhibitor was the most prescribed regimen across specialties (>50%).

CONCLUSIONS

Treatment intensification was underused in first lines of therapy across urology and oncology specialties despite evidence of improved survival. In subsequent lines, androgen deprivation therapy + androgen receptor pathway inhibitor was prescribed more frequently across specialties. These results underscore the need for earlier treatment intensification by urologists and oncologists.

Reasons for oncologist and urologist treatment choice in metastatic castration-sensitive prostate cancer (mCSPC): A physician survey linked to patient chart reviews in the United States

5065

Background: Based on level 1 evidence of overall survival, ASCO/NCCN/AUA guidelines uniformly recommend novel hormonal therapy (NHT) or chemotherapy (CHT) added to androgen deprivation therapy (ADT) as standard of care in mCSPC. However, real-world evidence across US healthcare systems suggests most patients receive ADT +/- first generation non-steroidal antiandrogens (NSAA). Reasons behind the lack of treatment intensification (TI) in mCSPC have not been studied. Methods: Data from medical charts of patients initiating mCSPC treatment from Jul ’18-Nov ‘21 were retrospectively extracted from multiple US academic/community practices. Oncologists and urologists who treated these patients were surveyed to provide reasons for treatment choices including prostate specific antigen (PSA) goals and explicit reasons for not prescribing NHT. Descriptive statistics (Fishers exact tests) were used to compare outcomes between groups; p-values for odds ratios (OR) were generated via Wald test. Results: 65 oncologists and 42 urologists provided data on 621 patients. Median age at initial mCSPC treatment start was 68.0 years, 58% were White, 25% Black, 84% had de novo metastases, 30% had high-volume disease including 22% with visceral metastases, and 83% had ECOG PS score ≤1. In the first-line (1L) setting, most mCSPC patients received ADT±NSAA alone (69%), while TI rates with ADT+NHT (26%) or ADT+CHT (4%) were low. An additional 27% (n = 166/621) received subsequent TI while still castration-sensitive. According to the physician survey, the top 5 reasons why their patients did not receive initial NHT were perceptions about: drug tolerability (38%), lack of clinical trial evidence of overall survival improvement (31%), lack of reimbursement (26%), patient financial constraints (20%), and questions about sequencing NHTs earlier vs later in disease (21%). Regarding treatment goals for PSA response, physicians more frequently reported a relative (%) reduction than an absolute PSA reduction (85% vs 51%). Oncologists considered a median PSA reduction of 50% (IQR 25-75) adequate vs 75% (IQR 50-90) among urologists. Urologists had higher rates of TI at 1L and/or subsequent treatment in patients who were still castration-sensitive (p < 0.01). Physicians who aimed for deeper PSA reduction of 75-100% were more likely (OR = 1.63; p = 0.034) to provide TI in 1L compared with physicians with less aggressive PSA goals (0-49%). Conclusions: To our knowledge, this is the first study identifying reasons for underutilization of intensified treatment in mCSPC. While survey results suggest perceptions of tolerability and lack of efficacy and financial considerations affect NHT use, in practice, non-guideline driven PSA reduction goals are associated with low rates of TI. These results demonstrate the need for further medical education.

Underutilization of standard of care (SOC) treatment intensification in patients (pts) with metastatic castration-sensitive prostate cancer (mCSPC) by specialty

183

Background: Intensification of androgen deprivation therapy (ADT) with docetaxel (DOC) or novel hormone therapies (NHTs) [abiraterone, enzalutamide, or apalutamide] has shown to improve survival outcomes and is SOC in men with mCSPC.1 However, recent evidence indicates that most pts still only receive ADT ± first-generation non-steroidal antiandrogens (NSAA).2-4 This is one of the first studies to assess the real-world utilization of intensified treatments as first-line (1L) therapies for pts with mCSPC by physician specialty. Methods: This retrospective study used the Optum health insurance claims database, which includes pt claims data from commercially insured and Medicare Advantage populations. Adult pts (≥18 years) had ≥2 claims for prostate cancer (PC) and ≥1 claim for metastasis (the first claim was index date) within 90 days (d) prior to, or any time after, the first claim for PC from January 2014– June 2019. 1L treatments included any systemic treatment for mCSPC within 90 d pre-index, plus any other treatment received within 180 d of the first. Physician specialty was determined from medical or pharmacy claims during 1L treatment and categorized as Urologist; Oncologist; urologists and oncologists (Both); or other specialties (Other). Treatment patterns and pt characteristics across specialties were analyzed descriptively. Results: Of 4,675 mCSPC pts identified, 16% received care from Urologists, 20% from Oncologists, 63% from Both, and 1% from Other. Pts seen by Urologists were more likely to be older and have Medicare compared to pts seen by the Oncologists or Both. Treatment intensification with NHT and/or DOC was numerically higher among Oncologists and Both compared with Urologists. However, all specialties prescribed ADT ± first-generation NSAA most frequently for 1L mCSPC treatment, even in patients with visceral metastases (Table). Conclusions: Despite evidence of improved survival with intensified treatment for pts with mCSPC, we observed its underuse by all specialties and even among pts with visceral metastases. Our results highlight a great need to advance the implementation of evidence-based medicine in mCSPC. 1. Sayegh N et al. JCO Oncol Pract 2021; OP2100206. 2. Ryan CJ et al. J Urol 2021; Online ahead of print. 3. Freedland S et al. Ann Oncol 2021; 32: S650-S651. 4. Freedland S et al. J Clin Oncol 2021; 39(Suppl 15): e5073.[Table: see text]

Prostate-specific antigen (PSA) outcomes in black (B) and white (W) chemotherapy-naïve (CN) prostate cancer (PC) patients (pts) treated with enzalutamide (ENZA)

20

Background: Population-level data suggest that B men are more likely to be diagnosed and die from PC. In juxtaposition, across multiple treatments for advanced PC, studies suggest B men have better survival than W men, including with novel hormone therapies (NHTs) such as ENZA. Whether improved survival is driven by better clinical response is unknown as data on racial differences in treatment response for ENZA are limited. This study assessed real-world PSA outcomes (response and progression) of ENZA-treated B vs W CN PC pts in the US. Methods: This retrospective cohort study included PC pts who initiated ENZA in the IntrinsiQ Specialty Solutions urology electronic medical records database from Sept 1, 2014 to Feb 28, 2018. The index date was the first prescription for ENZA. Patients with evidence of prior chemotherapy and/or abiraterone were excluded. Baseline characteristics, PSA response (PSA decline ≥50% or ≥90%), and clinical progression-free survival (cPFS) were assessed by race. Kaplan-Meier and Cox models adjusting for baseline characteristics were used to estimate PSA response and cPFS. Results: The study included 214 B and 1,332 W CN PC pts. Black pts were younger and had a higher baseline median PSA than W pts. Charlson Comorbidity Index (CCI), median duration of therapy, follow-up time, and number of post-index PSA tests were similar between races. In adjusted analyses, the chances of pts achieving ≥50% PSA decline was similar, whereas a numerically higher trend was observed for ≥90% PSA decline in B pts (Table). In addition, B men had significantly better cPFS (hazard ratio [HR] 0.82; 95% confidence interval [CI] 0.68, 0.98; p=0.03) [Table]. Conclusions: This real-world study found similar PSA response in B and W CN PC pts treated with ENZA but suggests that B pts may have better cPFS than W pts. Further research is warranted to validate these findings.[Table: see text]

Treatment patterns and survival in metastatic castration-sensitive prostate cancer in the US Veterans Health Administration

BACKGROUND

Limited real-world data exist on treatment patterns and outcomes in patients with metastatic castration-sensitive prostate cancer (mCSPC).

METHODS

A retrospective cohort study was conducted, using the Veterans Health Administration claims database (April 2013-March 2018). Among 369,734 prostate cancer patients, we selected all men who developed metastases within 90 days before or after medical/surgical castration and who received androgen deprivation therapy (ADT). Patients were categorized into four cohorts: ADT-only (± <90-day nonsteroidal anti-androgen [NSAA] use), ADT + NSAA, ADT + docetaxel, and ADT + abiraterone. Main outcomes were treatment patterns, time-to-progression to metastatic castration-resistant disease, and overall survival. Multivariable analysis and sensitivity analysis were conducted.

RESULTS

Of 1395 patients, 874 (63%) received ADT-only, 338 (24%) received ADT + NSAA, 108 (8%) received ADT + docetaxel, and 75 (5%) received ADT + abiraterone. Proportions on ADT-only and ADT + NSAA declined (from 66% to 60% and from 31% to 17%, respectively) over the study period, while proportions prescribed ADT + docetaxel or abiraterone increased from 3% to 9% and from 1% to 15%, respectively. Patients treated with ADT + NSAA had similar risks of castration-resistant disease (hazard ratio [HR] 1.05; 95% confidence interval [CI]: 0.87, 1.26) and overall mortality (HR 1.22; 95% CI: 0.97, 1.54) as ADT-only.

CONCLUSIONS

Most patients with mCSPC initiating ADT received ADT-only or ADT + NSAA, despite the emergence of docetaxel and novel hormonal therapies. Even in the most recent period (2017 to early 2018), only 24% of men received intensified therapy with agents known to prolong survival versus ADT-only. These data in real-world clinical practice suggest substantial room for improved outcomes in patients with mCSPC.

Kaposiform haemangioendothelioma in an adult: lack of response to topical sirolimus and response to radiotherapy

Kaposiform haemangioendothelioma (KHE) is a rare, primarily paediatric tumour with only a handful of case reports in the adult population. Given the paucity of evidence, this article is important in raising awareness of radiotherapy as a suitable and effective treatment in the adult population with KHE and highlights the potential limitations of topical sirolimus in these tumours.

Who writes dermatology randomized controlled trials? The need to specify the role of medical writers

Medical writers may make major contributions to the preparation of a manuscript, but are not listed as authors. We assessed the prevalence, affiliation and role of medical writers in dermatology randomized controlled trials (RCTs) published in 2019 in the top 7 medical and top 10 dermatology journals. Medical writers were identified in 39/83 trials (47%), all of which were exclusively industry-funded trials (39/47, prevalence 83%). Most studies stated their role as 'medical writing support' and/or 'editorial assistance' (35/39, 90%), but when more information was provided, four studies specified first draft preparation (50% of RCTs in general medical and 1.3% of RCTs in dermatology journals). Medical writers are common in dermatology trials but their role is often vaguely stated. In April 2020 the British Journal or Dermatology and Clinical and Experimental Dermatology adopted CRediT (Contributor Roles Taxonomy), which describes contributions of authors and may help clarify who writes trial manuscripts.

Real-world treatment patterns among patients diagnosed with metastatic castration-sensitive prostate cancer (mCSPC) in community oncology settings

5074

Background: Androgen deprivation therapy (ADT) served as standard of care for mCSPC for decades. Combining ADT with docetaxel (DOC) starting in 2015 or with novel hormonal therapies (NHT) starting in 2017 has demonstrated improved survival compared to ADT alone. This study examined the impact of new evidence on treatment selection for mCSPC patients in real-world oncology practice. Methods: Electronic medical record (EMR) data from a network of U.S.-based oncology practices in the ConcertAI Oncology Dataset were used to retrospectively evaluate treatment patterns in mCSPC patients who initiated first-line (1L) therapy between 2014–2019. We estimated the proportion of mCSPC patients receiving each 1L regimen, duration of therapy until initiation of next regimen, and trends in 1L regimen. Treatment patterns were studied in the overall population and by race/ethnicity. Anti-androgen (AA) use for <90 days was not included. Results: A total of 858 mCSPC patients were included (70% White, 16% Black, 3% Hispanic, and 11% other race/unknown). Median age at mCSPC diagnosis was 69 years, and 63% presented with de novo metastases. The most common mCSPC 1L regimens were ADT + older AA (26.3%, mainly bicalutamide), ADT monotherapy (20.5%), ADT + NHT ± AA (19.2%), and ADT + DOC ± AA (16.4%). The remaining 17.5% received a variety of other therapies, including AA monotherapy (5.9%) or NHT ± AA (5.5%). NHT included abiraterone, apalutamide, and enzalutamide. ADT + NHT ± AA treatment increased each year, while ADT + DOC ± AA treatment peaked in 2017 and then decreased (Table). By contrast, ADT + AA was the most common therapy in 2014 but declined every year. Median duration until initiation of a subsequent regimen was 14.3 months for ADT + NHT ± AA and 10.8 months for ADT + DOC ± AA. Differences in 1L treatment patterns across White and Black patients were not statistically significant in unadjusted analyses. Conclusions: Even in 2019, over half of mCSPC patients treated in real-world settings did not receive 1L therapy now known to significantly improve survival (ADT + NHT or ADT + DOC) over ADT alone. Those who did, received shorter durations of treatment than observed in registrational trials. However, we found no initial evidence of racial disparities in treatment. The disconnect between trial evidence and real-world practice could be due to patient/disease characteristics, cost/access issues, or provider awareness. A better understanding of these contributing factors is worthy of further study.[Table: see text]

Real-world utilization of advanced therapies and racial disparity among patients with metastatic castration-sensitive prostate cancer (mCSPC): A Medicare database analysis

5073

Background: Several randomized controlled trials have shown that adding docetaxel or novel hormonal therapy (NHT) to androgen deprivation therapy (ADT) improves survival in mCSPC patients. This study aimed to evaluate the real-world utilization of advanced therapies over time and to provide data on utilization patterns among racial minorities that are often under-represented in clinical trials. Methods: This was a retrospective analysis of a Medicare database (Jan 2009-Dec 2018). Adult men with ≥1 claim for prostate cancer (PC) who initiated ADT (index date) within 90 days prior to or any time after a metastasis diagnosis were included. The first-line (1L) treatment was grouped by PC drugs prescribed within 30 days prior to and 120 days after the index date, in 4 categories: ADT alone, ADT + first-generation anti-androgen (AA; ≥90 days to avoid capturing AA for flare control), ADT + docetaxel, and ADT + NHT (abiraterone, apalutamide, and enzalutamide). The 1L treatment distributions were described over time and stratified by race. Results: A total of 35,195 patients with mCSPC were included in the study, with a mean (SD) age of 76.5 (7.9) years. 11.8% were Black, 5.3% Hispanic, and 78.5% White. 76.4% received ADT alone as 1L treatment, 14.3% ADT + AA, 4.8% ADT + docetaxel, and 4.5% ADT + NHT. While the proportion of patients treated with ADT alone and ADT + AA slowly decreased over time, the utilization of ADT + docetaxel increased since 2015 and the utilization of ADT + NHT increased since 2017 (Table). After the emergence of NHTs for treatment of mCSPC in 2017, treatment intensification with ADT + NHT was numerically lower for Black than White patients. Data from before 2017 also suggest a similar lower use of ADT + AA in Black patients (Table). Survival analysis across treatment cohorts and race are ongoing. Conclusions: In this large and nationally representative sample of mCSPC patients, less than one-third of patients received treatment intensification by 2018, possibly due to patient/disease characteristics, provider awareness or therapeutic inertia, or cost. Importantly, the data showed less frequent treatment intensification in Black vs White patients. Further study is required to elucidate underlying reasons for this disparity.[Table: see text]

Real-world first-line (1L) treatment patterns in patients (pts) with metastatic castration-sensitive prostate cancer (mCSPC) in a U.S. health insurance database

5072

Background: Over the past 6 years, intensification of androgen deprivation therapy (ADT) with docetaxel (DOC) and novel hormonal therapies (NHT) [abiraterone, enzalutamide, and apalutamide], has been shown to improve survival outcomes in men with mCSPC. This study assessed the real-world utilization of effective combination therapies as 1L treatment in insured pts in the U.S. with mCSPC. Methods: This retrospective study used the Optum health insurance claims database, which includes pt claims data from both commercially insured and Medicare Advantage populations. Eligible pts were adult men with ≥1 claim with a metastatic International Classification of Diseases diagnostic code (first claim was index date) within 90 days (d) prior to, or any time after, a prostate cancer diagnosis between January 2014 and June 2019. Pts with evidence of systemic anticancer therapy during the 1-year pre-index baseline period were excluded, unless the first drug claim occurred within 90 d prior to the diagnosis of metastatic disease. The 1L treatments were identified as any treatment for mCSPC within 90 d pre-index, plus any other treatment received within 180 d of the first, and were grouped by regimen: ADT only; ADT + first-generation antiandrogens (AA); ADT + DOC; ADT + NHT; and ADT + NHT + DOC. Results: Of 4221 men with mCSPC, 2364 (56.0%) received ADT only; 892 (21.1%) ADT + AA; 577 (13.7%) ADT + NHT; 348 (8.2%) ADT + DOC; and 40 (0.9%) ADT + NHT + DOC. Pts who received ADT + DOC or ADT + DOC + NHT were generally younger than the other treatment groups (Table). By 2019, use of ADT only and ADT + AA had declined, while the use of ADT + NHT and ADT + NHT + DOC had increased (Table). However, in 2018 and 2019, the majority of men with mCSPC still received either ADT alone, or ADT + AA, including those with visceral metastases (Table). Survival analysis across treatment cohorts is ongoing. Conclusions: Despite level 1 evidence demonstrating improved survival with intensified treatment (ADT + DOC or NHT), this study shows its underutilization in pts with mCSPC. This is evident even in those with more aggressive disease (visceral metastases) as recently as 2019. These data highlight that a minority of pts with mCSPC received optimal life-prolonging therapies in a commercially insured and Medicare Advantage U.S. population. Further studies are needed to identify the reasons for this underutilization of intensified treatments.[Table: see text]

How prevalent are financial conflicts of interest in dermatology randomized controlled trials? A cross-sectional study

Since the last assessment of conflicts of interest (COIs) in dermatology randomized controlled trials (RCTs) in 2004, several countries have introduced transparency databases. We assessed the prevalence of financial COIs in dermatology RCTs and quantified payments from study sponsors to academic/clinical authors using transparency databases, which are available in the USA, France, Australia, Belgium and the Netherlands, while the UK has a noncompulsory transparency database. We included RCTs from the top 10 dermatology journals and the top 7 general medical journals published in 2019. The study assessed 83 RCTs, and COIs were identified in 69%. The highest prevalence was in exclusively industry-funded trials (46/47, 98%), which consisted of personal payments to an academic/clinical author (96% of trials) and having authors who were employees/stockholders (96%). Payments were identified for 31/56 (55%) academic/clinical first/final authors (median payment US$28 746, maximum US$597 299, interquartile range US$17 061-146 253), and 24/31 payments (77%) payments were each > US$10 000.

Survival outcomes in patients with metastatic castration-sensitive prostate cancer (mCSPC): A real-world evidence study

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Background: Androgen deprivation therapy (ADT) is the cornerstone of treatment for mCSPC patients. Clinical trials have recently shown that adding docetaxel (DOC) or novel hormonal therapies (NHT) to ADT improves survival in this population. Additionally, long-term (≥3 months) treatment with non-steroidal anti-androgens (AA) has been used to achieve combined androgen blockade. However, real-world evidence on survival outcomes in this setting is limited. Methods: Veterans Health Administration (VHA) claims data was used to compare time to metastatic castration-resistant prostate cancer (mCRPC) and overall survival (OS) in mCSPC men who initiated ADT alone or ADT with AA, DOC, or abiraterone (ABI) from April 1, 2014 to March 31, 2018. Propensity scores were calculated using logistics regression and adjusted for demographics (age, race) and patient characteristics at index (index year to ADT, radiation therapy, chronic corticosteroid use, Charlson Comorbidity Index score, select comorbidities, log(PSA), hemoglobin, alkaline phosphate, site of metastasis). Cox proportional hazard (CPH) models were used to evaluate time to progression to (mCRPC) and OS using stabilized inverse probability of treatment weighting (SIPTW) adjusting for body mass index, site of metastasis, time from metastatic diagnosis to index date, and log(PSA). Sensitivity analyses with CPH were conducted using propensity score matching (PSM). Results: The study included 1395 mCSPC men of which 874 (63%) were ADT only, 338 (24%) were ADT+AA (98% with bicalutamide), 75 (5%) were ADT+ABI, and 108 (8%) were ADT+DOC patients. Due to small sample sizes, adjusted survival analyses were not conducted on ADT+ABI and ADT+DOC cohorts. Post-SIPTW adjustment, patient characteristics were balanced between ADT+AA and ADT only cohorts. After treatment initiation, ADT+AA patients showed similar risk of progression to mCRPC (hazard ratio [HR]: 1.05 (95% CI: 0.87–1.26, P = .622), with a median time to mCRPC equal to 21.74 vs 22.5 months compared with ADT only. Patients treated with ADT+AA had similar risk of death compared to ADT only (HR: 1.22; 95% CI: 0.97–1.54, P = .093), with median survival not reached in both cohorts. Sensitivity analyses with PSM confirmed the results. Conclusions: Our study highlighted that most mCSPC patients in the VHA who initiated treatment between 2014 and 2018 were treated with ADT only despite the emergence of DOC or NHT combination therapies. Patients treated with ADT+AA had similar time to mCRPC and OS compared with ADT alone, but results should be treated with care as we could not adjust for all prognostic factors. Median time to mCRPC and OS in our study for both ADT and ADT+AA was similar to published data from corresponding placebo arms in NHT trials but inferior to outcomes in the treated arms of these trials, indicating significant room for survival improvement in the mCSPC population.

How Oncologists Perceive the Availability and Quality of Information Generated From Patient-Reported Outcomes (PROs)

Background:

Despite increased incorporation of patient-reported outcome (PRO) measures into clinical trials, information generated from PROs remains largely absent from drug labeling and electronic health records, giving rise to concerns that such information is not adequately informing clinical practice.

Objective:

To evaluate oncologists’ perceptions concerning the availability and quality of information generated from PRO measures. Additionally, to identify whether an association exists between perceptions of availability and attitudes concerning quality.

Method:

An online, 11-item questionnaire was developed to capture clinician perspectives on the availability and use of PRO data to inform practice. The survey also asked respondents to rate information on the basis of 4 quality metrics: “usefulness,” “interpretability,” “accessibility,” and “scientific rigor.”

Results:

Responses were received from 298 of 1301 invitations sent (22.9% response rate). Perceptions regarding the availability of PRO information differed widely among respondents and did not appear to be linked to practice setting. Ratings of PRO quality were generally consistent, with average ratings for the 4 quality metrics between “satisfactory” and “good.” A relationship was observed between ratings of PRO data quality and perceptions of the availability.

Conclusion:

Oncologists’ attitudes toward the quality of information generated from PRO measures are favorable but not enthusiastic. These attitudes may improve as the availability of PRO data increases, given the association we observed between oncologists’ ratings of the quality of PRO information and their perceptions of its availability.

Overall survival (OS) in men with chemotherapy-naïve metastatic castration-resistant prostate cancer (mCRPC) receiving bicalutamide (BIC) followed by enzalutamide (ENZA) or abiraterone (ABI)

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Background: The objective of this study was to evaluate real-world OS in men with chemotherapy-naïve mCRPC treated with first-line ENZA or ABI or sequencing to these agents after treatment with BIC ( > 90 d). Methods: A retrospective analysis was performed using the Veterans Health Administration (VA) database. Men with mCRPC and ≥ 1 pharmacy claim for ABI or ENZA (1st claim date = index date) following surgical or medical castration and with no chemotherapy treatment 12 months pre-index date were identified from 01APR2014 to 31MAR2017. Men had continuous VA enrollment for ≥ 12 months pre- index date and were followed until death or study end. Cox proportional hazards regression models examined the impact of treatment on OS, and the impact of first using BIC ( > 90 d) vs first-line use of ABI and ENZA on OS. Adjusted Kaplan-Meier analysis was conducted to graphically describe OS. Results: This study included 1229 ENZA- and 1945 ABI-treated men with mCRPC with mean ages of 74 and 73 y, respectively. Median follow‐up was 548 and 572 d, and median OS was 892 and 786 d, respectively. ENZA and ABI were first-line treatment in 1068 and 1628 men, but BIC ( > 90 d) was first used before sequencing to ENZA or ABI in 161 and 317 men, respectively. Median duration of BIC treatment was similar in men subsequently treated with ENZA or ABI (251 v 246 d, respectively). Compared with first-line ABI, use of ABI following BIC led to shorter OS (hazard ratio [HR] = 1.30; 95% CI 1.11 -1.52). Compared with first-line ENZA, use of ENZA following BIC resulted in a nonsignificant effect on OS (HR = 0.92; 95% CI 0.72-1.19). In the Cox analysis, ENZA-treated men had longer OS compared with ABI-treated men (HR = 0.84; 95% CI 0.76-0.94). Conclusions: Use of BIC ( > 90 d) before sequencing to ENZA did not negatively effect OS, however BIC before ABI impacted OS adversely in men with chemotherapy-naïve mCRPC. There are significant differences in OS favoring ENZA compared with ABI regardless of prior BIC. Real-world observational data are nonrandomized, and markers for disease severity/volume are not available in the claims database. Further research is required to confirm these findings.

Real-world analysis of prostate-specific antigen (PSA) outcomes among patients with metastatic castration-resistant prostate cancer (mCRPC) treated with enzalutamide (ENZA)

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Background: ENZA showed efficacy in chemotherapy-naïve men with mCRPC in a clinical trial setting (PREVAIL). We report real-world outcomes with ENZA for this population in a urology practice setting. Methods: This retrospective cohort study included men with prostate cancer newly initiating ENZA in the IntrinsiQ Specialty Solutions™ urology electronic medical records database between September 1, 2014 and February 28, 2018. Due to the approved indication in the study time frame, prescription of ENZA (first claim date = index date) was used as a proxy for mCRPC. Patients with evidence of prior chemotherapy and/or abiraterone were excluded. PSA value closest to index date (±30 days) was used as baseline. Men were followed until the earliest of: discontinuing ENZA, leaving practice, death, or study end. Best PSA response (largest decline or smallest increase in absence of decline from baseline), PSA declines of ≥50% and ≥90%, undetectable PSA, and time to PSA progression were analyzed. Results: We identified 931 eligible men. Most (>95%) were ≥60 years old; hypertension (54.6%) and diabetes (17.0%) were the most common comorbidities. Median (interquartile range [IQR]) baseline PSA was 9.0 (2, 37) ng/dL. Median (IQR) follow-up time was 12.5 (7.6, 19.4) months, during which a median (IQR) of 4 (3, 6) PSA tests were observed. Median time between two adjacent PSA tests was 2.0 months. A ≥50% and ≥90% PSA decline was observed in 55.0% and 23.8%, respectively. Best PSA response was a median (IQR) PSA decline of 58% (-89%, 1%), with 14.2% reaching an undetectable PSA value. Median time to PSA progression was 18.5 months (95% confidence interval 15.6, 23.7). Conclusions: This real-world study supports the effectiveness of ENZA in patients with mCRPC. The median PSA at treatment was much lower than PREVAIL, potentially explaining the longer time to PSA progression vs. PREVAIL. However, a lower proportion had PSA declines of ≥50% and ≥90% vs. PREVAIL, which may be attributed to more frequent PSA monitoring within a clinical trial setting and thus more opportunity to capture the true best PSA response.

Using velocity-pressure loops in the operating room: a new approach of arterial mechanics for cardiac afterload monitoring under general anesthesia

Cardiac afterload is usually assessed in the ascending aorta and can be defined by the association of peripheral vascular resistance (PVR), total arterial compliance (Ctot), and aortic wave reflection (WR). We recently proposed the global afterload angle (GALA) and β-angle derived from the aortic velocity-pressure (VP) loop as continuous cardiac afterload monitoring in the descending thoracic aorta. The aim of this study was to 1) describe the arterial mechanic properties by studying the velocity-pressure relations according to cardiovascular risk (low-risk and high-risk patients) in the ascending and descending thoracic aorta and 2) analyze the association between the VP loop (GALA and β-angle) and cardiac afterload parameters (PVR, Ctot, and WR). PVR, Ctot, WR, and VP loop parameters were measured in the ascending and descending thoracic aorta in 50 anesthetized patients. At each aortic level, the mean arterial pressure (MAP), cardiac output (CO), and PVR were similar between low-risk and high-risk patients. In contrast, Ctot, WR, GALA, and β-angle were strongly influenced by cardiovascular risk factors regardless of the site of measurement along the aorta. The GALA angle was inversely related to aortic compliance, and the β-angle reflected the magnitude of wave reflection in both the ascending and descending aortas (P < 0.001). Under general anesthesia, the VP loop can provide new visual insights into arterial mechanical properties compared with the traditional MAP and CO for the assessment of cardiac afterload. Further studies are necessary to demonstrate the clinical utility of the VP loop in the operating room.NEW & NOTEWORTHY Our team recently proposed the global afterload angle (GALA) and β-angle derived from the aortic velocity-pressure (VP) loop as continuous cardiac afterload monitoring in the descending thoracic aorta under general anesthesia. However, the evaluation of cardiac afterload at this location is unusual. The present study shows that VP loop parameters can describe the components of cardiac afterload both in the ascending and descending thoracic aorta in the operating room. Aging and cardiovascular risk factors strongly influence VP loop parameters. The VP loop could provide continuous visual additional information on the arterial system than the traditional mean arterial pressure and cardiac output during the general anesthesia.

Clinical, functional and radiological outcomes of extracorporeal irradiation in limb salvage surgery for bone tumours

AIMS

We present a retrospective review of patients treated with extracorporeally irradiated allografts for primary and secondary bone tumours with the mid- and long-term survivorship and the functional and radiographic outcomes.

PATIENTS AND METHODS

A total of 113 of 116 (97.4%) patients who were treated with extracorporeally irradiated allografts between 1996 and 2014 were followed up. Forms of treatment included reconstructions, prostheses and composite reconstructions, both with and without vascularised grafts. Survivorship was determined by the Kaplan-Meier method. Clinical outcomes were assessed using the Musculoskeletal Tumor Society (MSTS) scoring system, the Toronto Extremity Salvage Score (TESS) and Quality of Life-C30 (QLQ-30) measures. Radiographic outcomes were assessed using the International Society of Limb Salvage (ISOLS) radiographic scoring system.

RESULTS

There were 61 (54%) men with a mean age of 22 years (6 to 70) and 52 (46%) women with a mean age of 26 years (3 to 85). There were 23 deaths. The five-year patient survivorship was 82.3% and the ten-year patient survivorship was 79.6%. The mean follow-up of the 90 surviving patients was 80.3 months (2 to 207). At the last follow-up, 105 allografts (92.9%) were still in place or had been at the time of death; eight (7%) had failed due to infection, local recurrence or fracture. Outcome scores were comparable with or superior to those in previous studies. The mean outcome scores were: MSTS 79% (sd 8); TESS 83% (sd 19); QLQ 82% (sd 16); ISOLS 80.5% (sd 19). Pearson correlation analysis showed a strong relationship between the MSTS and ISOLS scores (r = 0.71, p < 0.001).

CONCLUSION

This study shows that extracorporeal irradiation is a versatile reconstructive technique for dealing with large defects after the resection of bone tumours with good functional and radiographic outcomes. Functional outcomes as measured by MSTS, TESS and QLQ-30 were strongly correlated to radiographic outcomes. Cite this article: Bone Joint J 2017;99-B:1681-8.

Temporal trends in thyroid-stimulating hormone (TSH) and thyroid peroxidase antibody (ATPO) testing across two phases of iodine fortification in Tasmania (1995-2013)

CONTEXT

Tasmania is an island state of the Australian Commonwealth with a well-documented history of mild iodine deficiency. Between 2001 and 2009, Tasmania experienced two incremental phases of iodine fortification.

OBJECTIVE

To examine trends in thyroid-stimulating hormone (TSH) and thyroid peroxidase antibody (ATPO) testing and their relationship to different phases of iodine nutrition in the Tasmanian population between 1995 and 2013.

DESIGN

Retrospective longitudinal study.

SETTING AND PARTICIPANTS

The major primary care and largest public hospital pathology providers in Tasmania submitted data for all TSH and ATPO tests performed between 1995 and 2013. Data linkage methodology was used to determine trends in TSH and ATPO testing.

RESULTS

A total of 1.66 million TSH assessments, involving 389,910 individual patients, were performed in Tasmania between 1995 and 2013. There was approximately a fourfold increase in the overall rate of TSH testing during this period with the rate of incident TSH assessment remaining relatively stable over the study period. The incidence of overt suppression and elevation of TSH (TSH≤0.1 mIU/L and ≥10 mIU/L) declined 62.3% and 59.7%, respectively, with a trend for increased incidence of borderline TSH elevation ≥4.0 mIU/L. The incidence of thyroid autoimmunity as determined by the proportion of abnormal ATPO results remained stable, with the absolute number of positive test results increasing during the study period.

CONCLUSION

Iodine supplementation of this mildly iodine-deficient population was not associated with an obvious increase in incidence of overt thyroid dysfunction or autoimmunity. Whilst the volume of TSH testing increased over the study period, the increase was driven by patients undergoing follow-up TSH assessments.

Abstract P3-07-11: Inhibition of Pin1 or CDK-mediated Smad3 phosphorylation reduces triple negative breast cancer cell EMT, migration and invasion

Introduction: Triple negative breast cancer (TNBC) is an aggressive subtype associated with poor outcomes. Accordingly, there is an urgent need to develop novel and targeted therapeutics for patients with this disease subtype. Cyclins D and E and the corresponding activation of CDK4/2 represent promising therapeutic targets for the treatment of TNBC. CDK4/2 can non-canonically phosphorylate Smad3, a key TGFβ signaling intermediate, and this phosphorylation is associated with the promotion of cell migration and EMT in cyclin-overexpressing breast cancers. Additionally, CDK-mediated Smad3 phosphorylation facilitates an interaction between Smad3 and Pin1. Pin1 is a cis-trans isomerase that is also overexpressed in aggressive breast cancers and can enable TNBC cell migration. Based on these findings, we hypothesized that blockade of the CDK-mediated Smad3-Pin1 interaction, either through inhibition of Pin1 or CDK-mediated Smad3 phosphorylation, would abrogate TNBC cell migration and invasion.

Methods: Pin1 expression was knocked-down (KD) in MDA-MB-231, MDA-MB-436, and Hs578T TNBC cells by transfection with Pin1-targeting siRNA (siPin1) or control non-specific siRNA (siNS). KD efficiency was confirmed with immunoblotting. Pin KD/TNBC cell migration and invasion assays were performed on uncoated or Matrigel-coated trans-wells, respectively. Media containing 10% FBS was used as a chemoattractant. Following Pin1 KD, immunoblotting was used to evaluate EMT-associated protein expression. To inhibit CDK-mediated Smad3 phosphorylation, TNBC cells were treated with 600 nM of CDK2 inhibitor (CDK2i) for 72 hours. Immunoblotting was then performed to determine Smad3 phosphorylation and EMT-associated protein expression. Co-immunoprecipitation assays were used to examine the impact of CDK2i treatment on the Smad3-Pin1 interaction. Finally, following CDK2i treatment, assays were performed to determine the ability of TNBC cells to migrate and invade.

Results: KD of Pin1 expression in TNBC cells resulted in a decrease in cell migration and invasion when compared to control cells in all the study cell lines. This corresponded with changes in EMT-associated protein expression, including increased levels of ZO-1 and claudin and decreased β-catenin. CDK2i treatment produced a decrease in Smad3 T179 site non-canonical phosphorylation and inhibited Smad3-Pin1 binding. CDK2i treatment also abrogated TNBC cell migration and invasion, paralleling expression changes in EMT-associated proteins with an increase in claudin and decrease in β-catenin.

Conclusions: Inhibition of the Smad3-Pin1 interaction, through KD of Pin1 expression or CDK2i-mediated blockade of non-canonical Smad3 phosphorylation, reduced TNBC cell EMT-type changes, demonstrated by increased expression of the tight junction proteins ZO-1 and claudin and decreased β-catenin, a key player in the WNT pathway. These findings also correlated to a reduction in TNBC cell migration and invasion. Collectively, these data show that the Smad3-Pin1 interaction, facilitated by CDK-mediated Smad3 phosphorylation, is associated with pro-migratory TGFβ signaling. Inhibition of this interaction, with CDK2 inhibitor treatment, may provide an important therapeutic option for TNBC patients.

Citation Format: Thomas AL, Hamdan R, Hong A, Lind H, Oppat K, Rosenthal E, Thomas AJ, Jeruss JS. Inhibition of Pin1 or CDK-mediated Smad3 phosphorylation reduces triple negative breast cancer cell EMT, migration and invasion [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-07-11.

Activity and safety of radiotherapy with anti-PD-1 drug therapy in patients with metastatic melanoma

The anti-PD-1 antibodies nivolumab and pembrolizumab are active in metastatic melanoma; however, there is limited data on combining anti-PD-1 antibody and radiotherapy (RT). We sought to review clinical outcomes of patients receiving RT and anti-PD-1 therapy. All patients receiving anti-PD-1 antibody and RT for metastatic melanoma were identified. RT and systemic treatment, clinical outcome, and toxicity data were collected. Fifty-three patients were included; 35 patients received extracranial RT and/or intracranial stereotactic radiosurgery (SRS) and 21 received whole brain radiotherapy (WBRT) (three of whom also received SRS/extracranial RT). Patients treated with extracranial RT or SRS received treatment either sequentially (RT then anti-PD-1, n = 11), concurrently (n = 16), or concurrent "salvage" treatment to lesions progressing on anti-PD-1 therapy (n = 15). There was no excessive anti-PD-1 or RT toxicity observed in patients receiving extracranial RT. Of six patients receiving SRS, one patient developed grade 3 radiation necrosis. In 21 patients receiving WBRT, one patient developed Stevens-Johnson syndrome, one patient developed acute neurocognitive decline, and one patient developed significant cerebral edema in the setting of disease. Response in irradiated extracranial/intracranial SRS lesions was 44% for sequential treatment and 64% for concurrent treatment (p=0.448). Likewise there was no significant difference between sequential or concurrent treatment in lesional response of non-irradiated lesions. For progressing lesions subsequently irradiated, response rate was 45%. RT and anti-PD-1 antibodies can be safely combined, with no detectable excess toxicity in extracranial sites. WBRT and anti-PD-1 therapy is well tolerated, although there are rare toxicities and the role of either anti-PD-1 or WBRT in the etiology of these is uncertain.

Abstract P5-04-13: Pin1 negatively impacts Smad3 tumor suppression in triple negative breast cancer cell lines

Introduction: Triple negative breast cancer (TNBC) is an aggressive subtype associated with poor outcomes. Accordingly, there is an urgent need to develop novel and targeted therapeutics for patients with this disease subtype. Cyclins D and E and the corresponding activation of CDK4/2 represent promising therapeutic targets for the treatment of TNBC. CDK4/2 can non-canonically phosphorylate Smad3, a key TGFβ signaling intermediate, to promote the transition from tumor suppressive to oncogenic TGFβ activity in cyclin-overexpressing breast cancers. We identified a Smad3 interaction with Pin1, a cis-trans isomerase also overexpressed in aggressive breast cancers and associated with CDK-mediated Smad3 phosphorylation. Smad3 interaction with Pin1 can influence protein function and fidelity through recruitment of Smurf2 and subsequent proteasomal degradation. Based on these findings, we hypothesized that inhibition of the CDK-mediated Smad3-Pin1 interaction would stabilize Smad3 protein expression and restore tumor-suppressive Smad3 activity.

Methods: Pin1 expression was knocked-down (KD) in MDA-MB-231 TNBC cells by transfecting with Pin1-targeting siRNA (siPin1) or control non-specific siRNA (siNS). KD efficiency was confirmed by immunoblotting. To assay Smad3 transcriptional activity with Pin1 KD, luciferase reporter studies were performed. Also, following Pin1 KD, immunoblotting was used to determine expression of Smad3 and associated protein targets. MTS assays were utilized to determine cellular proliferation after Pin1 KD. Transwell migration assays were used to assay the effect of Pin1 KD or CDK2 inhibitor treatment, which blocked non-canonical Smad3 Thr179 phosphorylation, on TNBC cell migration.

Results: KD of Pin1 expression in TNBC cell lines resulted in an increase in Smad3 transcriptional activity compared to control cells, and correlated with an increase in expression of cdki p15 and a decrease in c-myc, Smad3-target genes and cell cycle regulators. Additionally, Pin1 KD resulted in a significant decrease in TNBC cell proliferation compared to siNS control TNBC cells. Smad3 protein levels increased following Pin1 KD, suggesting Pin1 action may negatively impact Smad3 stability. We also found that KD of Pin1 or treatment with a CDK2 inhibitor, which blocked Smad3 noncanonical Thr179 phosphorylation, resulted in significantly reduced TNBC cell migration.

Conclusions: Inhibiting the Smad3-Pin1 interaction by knock-down of Pin1 expression in TNBC cells restored Smad3 transcriptional activity, which correlated to an increase in expression of the Smad3 associated protein cdki p15, decrease in c-myc, and a decrease in cellular proliferation. Additionally, Pin1 KD enhanced Smad3 protein levels, suggesting a role of Pin1 in mediating Smad3 stability. Inhibiting the Smad3-Pin1 interaction with Pin1 KD or CDK2 inhibitor treatment also reduced TNBC cell migration. Collectively, these data suggest that the Smad3-Pin1 interaction, facilitated by noncanonical CDK-mediated Smad3 phosphorylation, is associated with pro-tumorigenic and pro-migratory TGFβ signaling, and inhibition of this interaction may provide an important therapeutic option for TNBC patients.

Citation Format: Thomas AL, Hamdan R, Hong A, Rosenthal E, Thomas AJ, Jeruss JS. Pin1 negatively impacts Smad3 tumor suppression in triple negative breast cancer cell lines. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-04-13.

Loss of Fas apoptosis inhibitory molecule leads to spontaneous obesity and hepatosteatosis

Altered hepatic lipogenesis is associated with metabolic diseases such as obesity and hepatosteatosis. Insulin resistance and compensatory hyperinsulinaemia are key drivers of these metabolic imbalances. Fas apoptosis inhibitory molecule (FAIM), a ubiquitously expressed antiapoptotic protein, functions as a mediator of Akt signalling. Since Akt acts at a nodal point in insulin signalling, we hypothesize that FAIM may be involved in energy metabolism. In the current study, C57BL/6 wild-type (WT) and FAIM-knockout (FAIM-KO) male mice were fed with normal chow diet and body weight changes were monitored. Energy expenditure, substrate utilization and physical activities were analysed using a metabolic cage. Liver, pancreas and adipose tissue were subjected to histological examination. Serum glucose and insulin levels and lipid profiles were determined by biochemical assays. Changes in components of the insulin signalling pathway in FAIM-KO mice were examined by immunoblots. We found that FAIM-KO mice developed spontaneous non-hyperphagic obesity accompanied by hepatosteatosis, adipocyte hypertrophy, dyslipidaemia, hyperglycaemia and hyperinsulinaemia. In FAIM-KO liver, lipogenesis was elevated as indicated by increased fatty acid synthesis and SREBP-1 and SREBP-2 activation. Notably, protein expression of insulin receptor beta was markedly reduced in insulin target organs of FAIM-KO mice. Akt phosphorylation was also lower in FAIM-KO liver and adipose tissue as compared with WT controls. In addition, phosphorylation of insulin receptor substrate-1 and Akt2 in response to insulin treatment in isolated FAIM-KO hepatocytes was also markedly attenuated. Altogether, our data indicate that FAIM is a novel regulator of insulin signalling and plays an essential role in energy homoeostasis. These findings may shed light on the pathogenesis of obesity and hepatosteatosis.