Real-world comparative effectiveness of palbociclib plus aromatase inhibitor in HR+/HER2- metastatic breast cancer

Aim: Provide real-world data on palbociclib as evidence of effectiveness in patient populations from routine clinical practice. Methods: This was a retrospective, observational cohort study of patients with HR+/HER2- metastatic breast cancer treated with palbociclib plus aromatase inhibitor (AI) or AI alone as first-line therapy within the US Oncology Network. Results: Patients treated with palbociclib plus AI (n = 838) versus AI alone (n = 450) had a numerically longer median overall survival (42.1 vs 35.7 months; hazard ratio [HR] = 0.90 [95% CI: 0.75-1.07]; p = 0.117) and a significantly extended real-world progression-free survival (21.0 vs 15.7 months; HR = 0.75 [95% CI: 0.64-0.88]; p = 0.0002) after normalized inverse probability treatment weighting. Conclusion: These real-world results support the use of palbociclib plus AI as first-line treatment in routine clinical practice for patients with HR+/HER2- metastatic breast cancer.

Visualizing External Validity: Graphical Displays to Inform the Extension of Treatment Effects from Trials to Clinical Practice

BACKGROUND

In the presence of effect measure modification, estimates of treatment effects from randomized controlled trials may not be valid in clinical practice settings. The development and application of quantitative approaches for extending treatment effects from trials to clinical practice settings is an active area of research.

METHODS

In this article, we provide researchers with a practical roadmap and four visualizations to assist in variable selection for models to extend treatment effects observed in trials to clinical practice settings and to assess model specification and performance. We apply this roadmap and visualizations to an example extending the effects of adjuvant chemotherapy (5-fluorouracil vs. plus oxaliplatin) for colon cancer from a trial population to a population of individuals treated in community oncology practices in the United States.

RESULTS

The first visualization screens for potential effect measure modifiers to include in models extending trial treatment effects to clinical practice populations. The second visualization displays a measure of covariate overlap between the clinical practice populations and the trial population. The third and fourth visualizations highlight considerations for model specification and influential observations. The conceptual roadmap describes how the output from the visualizations helps interrogate the assumptions required to extend treatment effects from trials to target populations.

CONCLUSIONS

The roadmap and visualizations can inform practical decisions required for quantitatively extending treatment effects from trials to clinical practice settings.

Real-world utilization of immune checkpoint inhibitors in extensive stage small-cell lung cancer in community settings

Aim: This study examined real-world treatment patterns for extensive-stage small-cell lung cancer (ES-SCLC) after immune checkpoint inhibitors (ICIs) became available for frontline use. Methods: Adult patients with ES-SCLC initiating 1L systemic treatment were identified from electronic health records. Results: Among patients with recurrent/progressive ES-SCLC, the most common treatment classes were platinum-based chemotherapy (81.1% of 228) and ICI monotherapy (35.1% of 191) in 1L and 2L, respectively. Among patients with de novo ES-SCLC, the most common treatment classes were ICI + platinum-based chemotherapy (64.4% of 1268) and other chemotherapy (44.9% of 512) in 1L and 2L, respectively. Among patients who received no ICI in 1L, 62.6%-70.3% received it in 2L and 62.6-68.5% in 3L. Some who received 1L ICI were re-treated with ICI in subsequent lines (14.5-18.8% in 2L, 18.2-50.0% in 3L). Conclusion: Real-world ICI utilization in ES-SCLC, particularly ICI re-challenge, demonstrates high unmet needs in this patient population.

Real-world outcomes of 18,186 metastatic solid tumor outpatients: Baseline blood cell counts correlate with survival after immune checkpoint inhibitor therapy

BACKGROUND

Patient survival in advanced/metastatic melanoma, non-small cell lung cancer (NSCLC), and renal cell carcinoma (RCC) has improved with immune checkpoint inhibitors (ICI). Biomarkers' role in prognosis and treatment has been limited by conflicting trial results.

METHODS

This retrospective, observational study analyzed baseline demographic, clinical, laboratory, and treatment data versus outcomes of The US Oncology Network adult outpatients. Patients with advanced/metastatic melanoma, NSCLC, or RCC treated between January 1, 2015 and November 30, 2020 were given ICI monotherapy or combination therapy with ipilimumab, pembrolizumab, nivolumab, or atezolizumab. Treatment outcomes (overall survival [OS], time to treatment discontinuation, time to next treatment) were followed longitudinally until May 31, 2021, last patient record, or date of death. Baseline blood cell counts, including absolute monocyte count (AMC), absolute lymphocyte count (ALC), monocyte-to-lymphocyte ratio (MLR), absolute neutrophil count (ANC), and eosinophil count, were subdivided into quintiles for univariate and multivariable Cox regression analyses.

RESULTS

Data from 18,186 patients with advanced/metastatic melanoma (n = 3314), NSCLC (n = 12,416), and RCC (n = 2456) were analyzed. Better OS correlated with increased baseline serum albumin concentration, increased eosinophil and lymphocyte counts, and Western United States physician practice location. Decreased OS correlated with increased AMC, MLR, ANC, age, and worse Eastern Cooperative Oncology Group performance status.

CONCLUSIONS

To our knowledge, this study is the largest to date to associate baseline survival indicators and outcomes in outpatients with advanced/metastatic melanoma, NSCLC, or RCC and receiving ICIs. Results may inform disease-specific prognostic models and help providers identify patients most likely to benefit from ICI therapy.

Real-World Use of Positron Emission Tomography-Computed Tomography and Reported Deauville Scores in Advanced-Stage Classic Hodgkin Lymphoma: A Community Oncology Practice Perspective

PURPOSE

To evaluate the use of interim positron emission tomography-computed tomography (PET-CT) scans and Deauville 5-point scale (5PS) score reporting for stage III/IV classic Hodgkin lymphoma (cHL) treated frontline (1L) in community oncology settings.

METHODS

This retrospective, observational study included adults with stage III/IV cHL initiating 1L doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD), brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine, or an escalated dosing regimen of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone within the US Oncology Network between January 2017 and October 2019. Data were collected from electronic health records and chart reviews and summarized descriptively.

RESULTS

A total of 262 patients were included; 48.9% were age 39 years or younger. Most were male (57%), White (59%), had an International Prognostic Score <4 (76%), and received 1L ABVD (74%). Forty-nine percent of patients had stage III and 51% had stage IV cHL. Of 258 patients with ≥1 PET-CT scan, 71% (n = 184) had an interim scan and 64% received ≥1 scan at an off-site location. Of patients treated 1L with ABVD who received a baseline and interim scan, Deauville 5PS scores were not documented for 45% of patients; in 90% of these cases, a standardized uptake value (SUV) was reported.

CONCLUSION

In community oncology settings, under-reporting of Deauville 5PS scores for interim PET-CT scans was observed. In the absence of Deauville 5PS scores, SUV results were generally provided. These results highlight educational opportunities that exist for PET-adapted ABVD, including consistency in reporting/utilization of Deauville 5PS scores to de-escalate or escalate treatment.

Durvalumab real-world treatment patterns and outcomes in patients with stage III non-small-cell lung cancer treated in a US community setting

Background: For eligible patients with unresectable stage III non-small-cell lung cancer, durvalumab consolidation therapy following chemoradiotherapy is the standard of care. Methods: This was a retrospective study of durvalumab-treated patients diagnosed between 1 August 2017 and 29 February 2020. Electronic health record data were assessed descriptively, with Kaplan-Meier methods used for duration of treatment and overall survival (OS). Results: Among 528 patients (median age 70 years, 51.5% male), the median duration of treatment was 7.1 months (95% CI: 6.0-9.0). Estimated 1- and 2-year OS rates were 83.5 and 64.0%, respectively, with median OS not reached. Conclusion: This study confirmed an OS benefit with durvalumab after chemoradiotherapy in a real-world setting, consistent with the results from the PACIFIC phase III clinical trial.

Real-world relationship of early end points to survival end points in patients with resectable non-small-cell lung cancer

Aim: Pathologic response has been shown to be a promising surrogate for survival in non-small-cell lung cancer. We examined the real-world relationship between these end  points in patients with resectable stage IB-IIIA non-small-cell lung cancer receiving neoadjuvant chemotherapy/chemoradiotherapy (CT/CRT). Methods: Electronic health records/medical charts were analyzed. Overall and event-free survival (OS/EFS) were assessed by Kaplan-Meier stratified by pathologic response. Associations between the end  points were assessed by Cox analyses. Results: A total of 425 patients were selected for the study; 147 and 278 received CT and CRT, respectively. Pathologic complete response (pCR) was associated with longer OS (adjusted HR = 0.50; 95% CI: 0.29-0.85) and EFS (adjusted HR = 0.44; 95% CI: 0.28-0.68) versus no pCR, and EFS was associated with OS (HR = 0.51, 95% CI: 0.38, 0.69). Conclusion: In patients receiving neoadjuvant CT/CRT, pCR and EFS were associated with improved survival in this real-world dataset.

Real-World Tumor Response of Palbociclib in Combination With an Aromatase Inhibitor as First-Line Therapy in Pre/Perimenopausal Women With Metastatic Breast Cancer

BACKGROUND

Limited real-world data exist regarding the efficacy of palbociclib in combination with endocrine therapy in pre/perimenopausal women with metastatic breast cancer.

OBJECTIVE

We aimed to compare real-world tumor responses among pre/perimenopausal women who initiated palbociclib plus an aromatase inhibitor (AI) or AI monotherapy as first-line treatment for hormone receptor-positive/human epidermal growth factor receptor 2-negative metastatic breast cancer.

METHODS

This retrospective observational cohort study (NCT05012644) used electronic health record data from The US Oncology Network. Tumor responses were determined based on treating clinicians' assessments of radiologic evidence for changes in disease burden. Normalized inverse probability treatment weighting was used to balance baseline characteristics between treatment cohorts.

RESULTS

Of 196 pre/perimenopausal women, 116 and 80 were in the palbociclib plus AI cohort and AI cohort, respectively. Real-world response rates (complete or partial response) were 52.1% and 46.2%, respectively (odds ratio, 1.27 [95% confidence interval 0.72‒2.24]). Among patients with one or more tumor assessments on treatment, real-world response rates were 60.0% in the palbociclib plus AI cohort (n = 103) and 49.9% in the AI cohort (n = 71; odds ratio, 1.51 [95% confidence interval 0.82‒2.77]).

CONCLUSIONS

This real-world analysis suggests that pre/perimenopausal patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative metastatic breast cancer appear more likely to respond to palbociclib plus AI versus AI alone as first-line therapy, which may support the combination as a standard-of-care treatment for this patient population.

Comparing Trial and Real-world Adjuvant Oxaliplatin Delivery in Patients With Stage III Colon Cancer Using a Longitudinal Cumulative Dose

Importance

Delivery of adjuvant chemotherapy can differ substantially between trial and real-world populations. Adherence metrics like relative dose intensity (RDI) cannot capture the timing of modifications and mask differences in the total amount of chemotherapy received.

Objective

To compare oxaliplatin delivery between MOSAIC trial participants and patients treated in the US Oncology Network with stage III colon cancer using a longitudinal cumulative dose (LCD).

Design, Setting, and Participants

This cohort study used secondary data from the MOSAIC trial, an international randomized clinical trial (concluded in 2004), and electronic health records from US Oncology (2009-2018), a network of community oncology practices in the US. It included participants in MOSAIC with stage III colon cancer who were randomized to receive treatment with oxaliplatin and fluorouracil/leucovorin (n = 663) and US Oncology patients with stage III colon cancer who were treated with a modified FOLFOX-6 regimen (n = 2523).

Exposures

Oxaliplatin and fluorouracil/leucovorin.

Outcomes and Measures

We evaluated RDI and LCD over time and at the end of treatment in the MOSAIC and US Oncology populations. We used bootstrapping to estimate 95% confidence bands for LCD differences between the populations.

Results

The 663 MOSAIC participants (296 women [44.7%]) and 2523 US Oncology patients (1245 women [49.4%]) were generally similar with respect to demographic characteristics. Median RDI was lower in US Oncology (80% in MOSAIC vs 70% in US Oncology). The LCD also suggested differences in the total amount of oxaliplatin received between populations; the final median LCD in US Oncology was 10.2% lower than in MOSAIC, equivalent to receiving 1.2 fewer treatment cycles less of oxaliplatin. This difference only began 133 days into treatment and persisted after accounting for covariates, likely in terms of more frequent oxaliplatin treatment discontinuation in US Oncology patients than their MOSAIC counterparts.

Conclusions and Relevance

The study results suggest that real-world patients in community practice in the US treated with modified FOLFOX 6 received less oxaliplatin than their historical counterparts in the MOSAIC trial, with differences manifesting late in the treatment course. The LCD allowed us to identify the amount and extent of these differences, the timing of which was unclear when using RDI alone.

Trial Registration

ClinicalTrials.gov identifier: NCT00275210.

Oncology Drug Effectiveness from Electronic Health Record Data Calibrated Against RCT Evidence: The PARSIFAL Trial Emulation

Background

The use of electronic health records (EHR) data to assess drug effectiveness in clinical oncology practice is of great interest to regulators, clinicians, and payers. However, the utility of EHR data in clinical effectiveness studies may be limited by missing data, unmeasured confounding, and imperfect outcome surveillance. This study sought to emulate and compare the results of a randomized controlled trial investigating the efficacy of palbociclib with fulvestrant vs letrozole in advanced breast cancer.

Methods

This was a cohort study using longitudinal EHR data derived from outpatient oncology practices in the United States. Eligibility criteria from the PARSIFAL trial were emulated as closely as possible. Patients were included if they had hormone-positive, human epidermal growth factor receptor - 2 (HER-2) negative metastatic breast cancer and had no record of prior treatment for metastatic disease. Patients initiating first-line treatment with palbociclib and fulvestrant following their first record of metastasis were compared to those initiating palbociclib and letrozole on the same day. Treatments were ascertained by oncology medication ordering records in the data source. The primary outcome was death as recorded in the oncologists' EHR systems.

Results

There were 1886 eligible women in the study cohort. Although the 3-year survival was meaningfully lower in clinical practice (59%) compared to the randomized trial (78%), the relative effect size was a hazard ratio (HR) of 1.07 (95% CI: 0.86-1.35), similar to the randomized trial (HR = 1.00; 95% CI: 0.68-1.48).

Conclusion

Despite common challenges encountered in EHR-based studies, it is possible to achieve similar conclusions to emulated randomized trials with the application of analytic approaches that address missing data, confounding, and selection bias. This is a promising finding in light of other emulations and ongoing efforts to improve data from clinical practice and causal analytics.

Practice radiation patterns among oncologists in the Oncology Care Model

OBJECTIVES

CMS created the Oncology Care Model (OCM) to increase the delivery of cost-efficient cancer care, but in linking medical oncologist compensation to total costs of care, the model also prompted concerns about reductions in radiation therapy utilization. We compare practices that participated in the model with those that did not through its launch to estimate whether radiation therapy utilization was reduced under the OCM.

STUDY DESIGN

Retrospective analysis of a secondary claims-based data set.

METHODS

We used 5 years of reimbursement claims data from a large community oncology network in which approximately half of the practices participated in the OCM to measure the relative change in utilization following OCM participation compared with practices that did not participate in the OCM. We evaluated use of radiation therapy for all cancer diagnoses and, more specifically, bone metastases, lung cancer, and breast cancer to assess whether effects varied by setting using 3 quasi-experimental estimation techniques (difference-in-differences, event study, and triple differences regressions).

RESULTS

We found no evidence of reductions in radiation therapy utilization associated with the OCM between participant and nonparticipant practices in any of the specifications or subpopulations analyzed.

CONCLUSIONS

Despite the potential incentives for medical oncologists to reduce radiation therapy utilization, we found no evidence that such reduction occurred.

Treatment patterns and outcomes for patients with newly diagnosed glioblastoma multiforme: a retrospective cohort study

Aim:

Investigate real-world outcomes and healthcare utilization of patients with glioblastoma multiforme (GBM) related to O⁶-methylguanine DNA methyltransferase (MGMT) promoter testing and methylation.

Patients & methods:

US Oncology Network data were analyzed for patients receiving first-line (1L) treatment for GBM.

Results:

Most patients received 1L radiation with temozolomide. Unadjusted median overall survival (OS) was higher in tested versus untested (median:18.1 vs 11.8 months) and in methylated versus unmethylated (median: 25.5 vs 12.4 months). Untested status, unmethylated MGMT and older age were associated with reduced OS and longer 1L treatment with increased OS. Similar findings were observed for progression-free survival. Utilization was similar between cohorts.

Conclusion:

In community oncology practices, MGMT methylation and testing were predictive of better survival in GBM.

We studied the characteristics and survival of patients with newly diagnosed glioblastoma multiforme (GBM) in community-based oncology practices. These patients had received temozolomide and radiotherapy with surgery, which is the standard of care for GBM. We were interested in how patient survival was related to methylation of the O⁶-methylguanine DNA methyltransferase (MGMT) promoter. The study showed that patients with methylated versus unmethylated MGMT GBM survived longer. However, patients who were tested for methylation, whether MGMT was methylated or not, also survived longer. This may be because patients who get tested also get better care in general.

Recurrence rates in patients with HER2+ breast cancer who achieved a pathological complete response after neoadjuvant pertuzumab plus trastuzumab followed by adjuvant trastuzumab: a real-world evidence study

PURPOSE

This study assessed real-world risk of invasive disease recurrence (IDR) and associated factors in patients with human epidermal growth factor receptor-2 positive (HER2+) early breast cancer (BC) with pathological complete responses (pCR) after neoadjuvant pertuzumab plus trastuzumab (nPT) plus chemotherapy, followed by adjuvant trastuzumab (aT).

METHODS

Patients with HER2+ BC with pCR after nPT from 2013 to 2015 who received aT were identified in the US Oncology Network and followed until IDR or censoring. Kaplan-Meier and Cox regression methods were used to assess invasive disease-free survival (iDFS) and correlation between iDFS and patient characteristics.

RESULTS

A total of 217 pCR patients' charts were reviewed; median age was 52 years. Most had stage IIA or IIB disease (62%), Eastern Cooperative Oncology Group performance status (ECOG PS) ≤ 1 (84%), tumor size > 2 cm (75%), positive nodes (N+, 62%) and negative estrogen and progesterone receptor (ER- and PR-) expression (52%). Four-year iDFS rates were 90.0% overall (95% CI 84.6%, 93.6%), 86.2% for the N+ cohort and 96.0% for the N- cohort. Cox regression suggested that age, body mass index, ECOG PS, N+ status, stage T3 or T4, and ER+ or PR+ status were risk factors for IDR but were not statistically significant.

CONCLUSIONS

Consistent with previous studies, this real-world study observed that patients with HER2+ BC showing pCR with nPT remain at risk for IDR, especially with node-positive disease at diagnosis. Alternatives to adjuvant trastuzumab alone, including combined trastuzumab and pertuzumab, should be considered to improve outcomes for initially N+ patients showing pCR with nPT.

PRRSV detection by qPCR in processing fluids and serum samples collected in a positive stable breeding herd following mass vaccination of sows with a modified live vaccine

In the last two decades, in France, Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) stabilization protocols have been implemented using mass vaccination with a modified live vaccine (MLV), herd closure and biosecurity measures. Efficient surveillance for PRRSV is essential for generating evidence of absence of viral replication and transmission in pigs. The use of processing fluid (PF) was first described in 2018 in the United States and was demonstrated to provide a higher herd-level sensitivity compared with blood samples (BS) for PRRSV monitoring. In the meantime, data on vertical transmission of MLV viruses are rare even as it is a major concern. Therefore, veterinarians usually wait for several weeks after a sow mass vaccination before starting a stability monitoring. This clinical study was conducted in a PRRSV-stable commercial 1000-sow breed-to-wean farm. This farm suffered from a PRRS outbreak in January 2018. After implementing a stabilisation protocol, this farm was controlled as stable for more than 9 months before the beginning of the study. PF and BS at weaning were collected in four consecutive batches born after a booster sow mass MLV vaccination. We failed to detect PRRSV by qPCR on PF and BS collected in a positive-stable breeding herd after vaccination with ReproCyc® PRRS EU (Boehringer Ingelheim, Ingelheim, Germany).

Evaluation of Practice Patterns Among Oncologists Participating in the Oncology Care Model

Importance

Health insurers reimburse clinicians in many ways, including the ubiquitous fee-for-service model and the emergent shared-savings models. Evidence on the effects of these emergent models in oncological treatment remains limited.

Objectives

To analyze the early use and cost associations of a recent Medicare payment program, the Oncology Care Model (OCM), which included a shared savings-like component.

Design, Setting, and Participants

This nonrandomized controlled study used a difference-in-differences approach on 2 years of data, from July 1, 2015, to June 30, 2017-1 year before and 1 year after launch of the OCM-to compare the differences between participating and nonparticipating practices, controlling for patient, clinician, and practice factors. Participation in the OCM began on July 1, 2016. Associations of participation with care use and cost were estimated for care directly managed by clinicians from a large network within their Medicare populations for breast, lung, colon, and prostate cancers. Data were analyzed from September 2019 to March 2020.

Exposures

Participating practices were paid a monthly management fee of $160 per beneficiary and a potential risk-adjusted performance-based payment for eligible patients who received chemotherapy treatment, in addition to standard fee-for-service payments.

Main Outcomes and Measures

Office visits, drug administrations, patient hydrations, drug costs, and total costs.

Results

Monthly means data at the physician-level were evaluated for 11 869 physician-months for breast cancers, 11 135 physician-months for lung cancers, 8592 physician-months for colon cancers, and 9045 physician-months for prostate cancers. Patients at OCM practices had a mean (SD) age of 63.4 (3.1) years, and a mean (SD) of 59% (7 percentage points) of their patients were women. Participation in the OCM was associated with less physician-administered prostate cancer drug use (difference, 0.29 [95% CI, -0.47 to -0.11] percentage points, or 24.0%) translating to a mean of $706 (95% CI, -$1383 to -$29) less in drug costs per month. Monthly drug costs were also lower, at $558 (95% CI, -$1173 to $58) less for treatment for lung cancer. Total costs were lower by 9.7% or $233 (95% CI, -$495 to $30) for breast cancer, 9.9% or $337 (95% CI, -$618 to -$55) for lung cancer, 14.2% or $385 (95% CI, -$780 to $10) for colon cancer, and 29.2% or $610 (95% CI, -$1095 to -$125) for prostate cancer; however, these differences were largely offset by program costs. Clinician visits were also lower by 11.2% or 0.11 (95% CI, -0.20 to -0.01) percentage points among patients with breast cancer and by 14.4% or 0.19 (95% CI, -0.37 to -0.02) among patients with colon cancer.

Conclusions and Relevance

These findings suggest that payment models with shared-savings components can be associated with fewer visits and lower costs in certain cancer settings in the first year, but the savings can be modest given the costs of program administration.

Assessment of ERBB2/HER2 Status in HER2-Equivocal Breast Cancers by FISH and 2013/2014 ASCO-CAP Guidelines

Importance

The 2013/2014 American Society of Clinical Oncology and College of American Pathologists (ASCO-CAP) guidelines for HER2 testing by fluorescence in situ hybridization (FISH) designated an "equivocal" category (average HER2 copies per tumor cell ≥4-6 with HER2/CEP17 ratio <2.0) to be resolved as negative or positive by assessments with alternative control probes. Approximately 4% to 12% of all invasive breast cancers are characterized as HER2-equivocal based on FISH.

Objective

To evaluate the following hypotheses: (1) genetic loci used as alternative controls are heterozygously deleted in a substantial proportion of breast cancers; (2) use of these loci for assessment of HER2 by FISH leads to false-positive assessments; and (3) these HER2 false-positive breast cancer patients have outcomes that do not differ from clinical outcomes for patients with HER2-negative breast cancer.

Design, Setting, and Participants

We retrospectively assessed the use of chromosome 17 p-arm and q-arm alternative control genomic sites (TP53, D17S122, SMS, RARA, TOP2A), as recommended by the 2013/2014 ASCO-CAP guidelines for HER2 testing, in patients whose data were available through Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and whose tissues were available through the Breast Cancer International Research Group clinical trials. We used data from an international cohort database of invasive breast cancers (1980 participants) and international clinical trial of adjuvant chemotherapy in invasive, node-positive breast cancer patients.

Main Outcomes and Measures

The primary objectives were to (1) assess frequency of heterozygous deletions in chromosome 17 genomic sites used as FISH internal controls for evaluation of HER2 status among HER2-equivocal cancers; (2) characterize impact of using deleted sites for determination of HER2-to-internal-control-gene ratios; (3) assess HER2 protein expression in each subgroup; and (4) compare clinical outcomes for each subgroup.

Results

Of the 1980 patients in METABRIC,1915 patients were fully evaluated. In addition, 100 HER2-equivocal breast cancers by FISH and 100 comparator FISH-negative breast cancers from the BCIRG-005 trial were analyzed. Heterozygous deletions, particularly in specific p-arm sites, were common in both HER2-amplified and HER2-not-amplified breast cancers. Use of alternative control probes from these regions to assess HER2 by FISH in HER2-equivocal as well as HER2-not-amplified breast cancers resulted in high rates of false-positive ratios (HER2-to-alternative control ratio ≥2.0) owing to heterozygous deletions of control p-arm genomic sites used in ratio denominators. Misclassification of HER2 status was observed not only in breast cancers with ASCO-CAP equivocal status but also in breast cancers with an average of fewer than 4.0 HER2 copies per tumor cell when using alternative control probes.

Conclusions and Relevance

The indiscriminate use of alternative control probes to calculate HER2 FISH ratios in HER2-equivocal breast cancers may lead to false-positive interpretations of HER2 status resulting from unrecognized heterozygous deletions in 1 or more of these alternative control genomic sites and incorrect HER2 ratio determinations.

HOUT-02. TREATMENT PATTERNS AND OUTCOMES FOR PATIENTS WITH NEWLY-DIAGNOSED GLIOBLASTOMA MULTIFORME IN A US COMMUNITY ONCOLOGY SETTING

BACKGROUND

This study aims to describe real world characteristics and outcomes of newly-diagnosed glioblastoma multiforme (GBM) patients in relationship to O6-methylguanine DNA methyltransferase promoter (MGMT) testing and methylation status, in the US.

METHODS

Patients receiving care for GBM were identified in the US Oncology Network database from 1/1/2013 to 6/30/2018 and followed up to 9/30/2018. Structured data and chart reviews were used to assess demographic and clinical characteristics, treatment patterns, type of surgery, MGMT methylation, and clinical outcomes.

RESULTS

Of 600 patient charts planned for review, 195 have been randomly selected and reviewed thus far. Of these, 165 (84.6%) had surgical resection and 30 (15.4%) had biopsy only. Eighty-eight (45.1%) patients were tested for MGMT status and 107 (54.9%) were not. Of those tested, 33 (37.5%) were methylated, and 45 (51.1%) unmethylated. Median ages in the overall (including tested and untested), methylated and unmethylated cohorts were 63.7, 58.8, and 66.7 years, respectively. Most common first-line (1L) treatment in overall, methylated, and unmethylated cohorts was radiation concurrent with temozolomide received by 86.2%, 93.9%, and 91.1%, respectively. Median duration of 1L treatment in the overall cohort was 15.1 weeks (95% confidence interval [CI]: 11.9, 21.6) and higher in the methylated vs. unmethylated cohort (25.9 [18.1, 34.6] vs. 15.1 [9.3, 23.4] weeks, p=0.0375). Unadjusted median overall survival and progression-free survival in the overall cohort were 11.4 [9.4, 14.0] months and 5.2 [3.9, 5.8] months, and higher in the methylated vs. unmethylated cohort (20.5 [14.9, not realized] vs. 12.2 [7.1, 17.0] months, p=0.0052, and 9.4 [5.6, 14.0] vs. 5.5 [3.3, 6.8], p=0.0092, respectively).

CONCLUSIONS

Fewer than half of GBM patients were tested for MGMT methylation in the US community. Clinical outcomes, while better among patients with methylated MGMT, remain poor and current treatment options are limited.

Outcomes in patients with metastatic bladder cancer in the USA: a retrospective electronic medical record study

Aim: Investigate the effectiveness of chemotherapy for first-line (1L) treatment of metastatic bladder cancer (mBC). Methods: Retrospective cohort study evaluating treatment patterns/outcomes in 1155 mBC patients receiving initial treatment in the community practice setting from January 2010 to June 2014, and followed through July 2016. Results: The most commonly utilized 1L and second-line (2L) regimens were platinum-based and taxane-based, respectively. Median (95% CI) OS for all patients from 1L initiation was 12.8 months (11.7–14.6), and median OS for all 2L regimens was 9.4 months (8.2–11.1). Conclusion: mBC patients eligible for and who received cis-based regimens experienced better OS results. Poor renal function was a key driver of cis-ineligibility. The various monotherapy and combination chemotherapy regimens in 2L produced relatively short OS outcomes.

PIK3CA alterations and benefit with neratinib: analysis from the randomized, double-blind, placebo-controlled, phase III ExteNET trial

BACKGROUND

Neratinib is an irreversible pan-HER tyrosine kinase inhibitor that inhibits PI3K/Akt and MAPK signaling pathways after HER2 receptor activation. The ExteNET study showed that neratinib significantly improved 5-year invasive disease-free survival (iDFS) in women who completed trastuzumab-based adjuvant therapy for early breast cancer (EBC). We assessed the prognostic and predictive significance of PIK3CA alterations in patients in ExteNET.

METHODS

Participants were women aged ≥ 18 years (≥ 20 years in Japan) with stage 1-3c (modified to stage 2-3c in February 2010) operable breast cancer, who had completed (neo)adjuvant chemotherapy plus trastuzumab ≤ 2 years before randomization, with no evidence of disease recurrence or metastatic disease at study entry. Patients were randomized to oral neratinib 240 mg/day or placebo for 1 year. Formalin-fixed, paraffin-embedded primary tumor specimens underwent polymerase chain reaction (PCR) PIK3CA testing for two hotspot mutations in exon 9, one hot-spot mutation in exon 20, and fluorescence in situ hybridization (FISH) analysis for PIK3CA amplification. The primary endpoint (iDFS) was tested with log-rank test and hazard ratios (HRs) estimated using Cox proportional-hazards models.

RESULTS

Among the intent-to-treat population (n = 2840), tumor specimens were available for PCR testing (991 patients) and PIK3CA FISH (702 patients). Overall, 262 samples were PIK3CA altered: 201 were mutated (77%), 52 (20%) were amplified, and 9 (3%) were mutated and amplified. iDFS was non-significantly worse in placebo-treated patients with altered vs wild-type PIK3CA (HR 1.34; 95% CI 0.72-2.50; P = 0.357). Neratinib's effect over placebo was significant in patients with PIK3CA-altered tumors (HR 0.41; 95% CI 0.17-0.90, P = 0.028) but not PIK3CA wild-type tumors (HR 0.72; 95% CI 0.36-1.41; P = 0.34). The interaction test was non-significant (P = 0.309).

CONCLUSIONS

Although there was a greater absolute risk reduction associated with neratinib treatment of patients with PIK3CA-altered tumors in ExteNET, current data do not support PIK3CA alteration as a predictive biomarker of response to neratinib in HER2-positive EBC.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT00878709 . Trial registered April 9, 2009.

Abstract PD3-11: HER2/ERBB2 status in “HER2 equivocal” breast cancers by FISH and ASCO-CAP guidelines: False-positives due to heterozygous deletions of alternative control loci

Background. The ASCO-CAP guidelines for HER2 testing by fluorescence in situ hybridization (FISH) have a category, referred to as “equivocal” (average HER2 copies per tumor cell &gt;4-6 with HER2/CEP17 ratio &lt;2·0), which is neither “HER2-positive” nor “HER2-negative”. Approximately 4% - 12% of invasive breast cancers are “HER2-equivocal” based on FISH. Cancers in this category may be resolved as “negative” or “positive” by FISH alternative control probes (2013/2014 guidelines) or HER2 immunohistochemistry (IHC) (2018 update). Our objectives were to evaluate the following hypotheses: 1.) Genetic loci used as alternative controls show heterozygous deletion in a substantial proportion of breast cancers; 2.) Use of these loci for assessment of HER2 by FISH leads to false-positives; 3.) HER2 FISH false-positive breast cancer patients have outcomes that do not differ from clinical outcomes for HER2-negative breast cancer patients; and 4.) HER2-equivocal breast cancers seldom show HER2 protein overexpression (IHC 3+).

Methods. We retrospectively assessed the use of chromosome 17 p-arm and q-arm alternative control genomic sites (TP53, D17S122, SMS, RARA, TOP2A), as recommended by the 2013/2014 ASCO-CAP guidelines, in patients whose data were available through the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC)(N=1980) or whose tissues were available from the BCIRG-005 clinical trial (N=3298). We used either FDA-approved HER2 IHC (HercepTest) or laboratory-developed HER2 (10H8) IHC assays to assess HER2 protein expression.

Results. Using METABRIC we found heterozygous deletions, particularly in specific p-arm sites, were common in both HER2-amplified and HER2-not-amplified breast cancers. Use of alternative control probes from these regions to assess HER2 by FISH in “HER2 equivocal” as well as HER2-not-amplified breast cancers resulted in high rates of false-positive ratios (HER2-to-alternative control ratio &gt;2·0) due to heterozygous deletions of control p-arm genomic sites used as ratio denominators. Misclassifications of HER2 status was observed not only in breast cancers with ASCO-CAP “equivocal” status but also in breast cancers with an average of &lt;4·0 HER2 copies per tumor cell. These deletions were also identified by FISH. IHC demonstrated &lt;1% of FISH “HER2-equivocal” breast cancers in BCIRG-005 had IHC3+ immunostaining, consistent with HER2-not-amplified status. Clinical outcomes of “HER2-equivocal” breast cancer patients with HER2-to-alternative control ratio &gt;2·0 did not differ significantly from clinical outcomes of those with HER2-to-alternative control ratio&lt;2·0.

Conclusion. Using chromosome 17 p-arm alternative controls, as recommended by 2013/2014 ASCO-CAP guidelines, instead of CEP17 for resolution of “HER2 equivocal” cases, is problematic due to frequent heterozygous deletions of these loci in breast cancers. The indiscriminate use of alternative control probes to calculate a HER2 FISH ratio in “HER2-equivocal” breast cancers leads to false-positive interpretations of HER2 status resulting from unrecognized heterozygous deletions in one or more of these alternative control genomic sites and incorrect HER2 ratio determinations.

Citation Format: Press MF, Seoane JA, Curtis C, Quinaux E, Guzman R, Sauter G, Eiermann W, Mackey JR, Robert N, Pienkowski T, Crown J, Martin M, Valero V, Bee V, Ma Y, Villalobos I, Slamon DJ. HER2/ERBB2 status in “HER2 equivocal” breast cancers by FISH and ASCO-CAP guidelines: False-positives due to heterozygous deletions of alternative control loci [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD3-11.

Factors associated with the growing-finishing performances of swine herds: an exploratory study on serological and herd level indicators

Background

Growing and finishing performances of pigs strongly influence farm efficiency and profitability. The performances of the pigs rely on the herd health status and also on several non-infectious factors. Many recommendations for the improvement of the technical performances of a herd are based on the results of studies assessing the effect of one or a limited number of infections or environmental factors. Few studies investigated jointly the influence of both type of factors on swine herd performances. This work aimed at identifying infectious and non-infectious factors associated with the growing and finishing performances of 41 French swine herds.

Results

Two groups of herds were identified using a clustering analysis: a cluster of 24 herds with the highest technical performance values (mean average daily gain = 781.1 g/day +/− 26.3; mean feed conversion ratio = 2.5 kg/kg +/− 0.1; mean mortality rate = 4.1% +/− 0.9; and mean carcass slaughter weight = 121.2 kg +/− 5.2) and a cluster of 17 herds with the lowest performance values (mean average daily gain =715.8 g/day +/− 26.5; mean feed conversion ratio = 2.6 kg/kg +/− 0.1; mean mortality rate = 6.8% +/− 2.0; and mean carcass slaughter weight = 117.7 kg +/− 3.6). Multiple correspondence analysis was used to identify factors associated with the level of technical performance. Infection with the porcine reproductive and respiratory syndrome virus and the porcine circovirus type 2 were infectious factors associated with the cluster having the lowest performance values. This cluster also featured farrow-to-finish type herds, a short interval between successive batches of pigs (≤3 weeks) and mixing of pigs from different batches in the growing or/and finishing steps. Inconsistency between nursery and fattening building management was another factor associated with the low-performance cluster. The odds of a herd showing low growing-finishing performance was significantly increased when infected by PRRS virus in the growing-finishing steps (OR = 8.8, 95% confidence interval [95% CI]: 1.8–41.7) and belonging to a farrow-to-finish type herd (OR = 5.1, 95% CI = 1.1–23.8).

Conclusions

Herd management and viral infections significantly influenced the performance levels of the swine herds included in this study.

Electronic supplementary material

The online version of this article (10.1186/s40813-018-0082-9) contains supplementary material, which is available to authorized users.

Abstract P5-16-02: Variance between experts and community practitioners in treatment of metastatic breast cancer

Background

New treatment options continue to improve outcomes for patients with metastatic breast cancer (MBC). However, clinicians' lack of clinical experience using new agents, a complex treatment landscape, and the broad treatment recommendations in available guidelines can make the choice of an optimal treatment for individual patients with MBC challenging. An online treatment decision support tool was developed to overcome these challenges and provide recommendations from multiple experts for specific MBC patient scenarios. Here we report data comparing expert treatment recommendations with the intended treatment indicated by clinicians using the tool.

Methods

In October 2016, 5 breast cancer experts provided treatment consultation for 492 unique MBC case scenarios based on a simplified set of variables: disease phenotype, previous systemic therapy, visceral crisis (yes/no), and rate of disease progression. These patient and disease characteristics along with expert treatment consultation were used to develop the treatment decision tool. Clinicians used drop-down menus to enter patient and disease factors along with their intended treatment plan. When completed, the experts' treatment recommendations for that specific patient case were shown to the clinicians, at which point the users were asked to indicate if the expert recommendations changed their planned treatment.

Results

From December 2016 through April 2017, 619 healthcare providers entered 1018 patient case scenarios in the online MBC tool representing the following phenotypes: HR+/HER2- (53%), HR-/HER2+ (10%), HR+/HER2+ (14%), and triple-negative breast cancer (23%). A comparison of expert and community oncologist treatment choices in select patient case scenarios with expert consensus is shown in the table. Among participating oncologists whose initial intended treatment of MBC differed from the experts, 51% indicated that they would change their choice of therapy.

Conclusions

MBC therapy continues to evolve with new agents having a large impact on how experts treat MBC. Data from the online MBC treatment decision support tool indicate variance in expert and oncologist treatment choices for many case scenarios. Moreover, consensus expert recommendations in this online tool changed the intended treatment plan of many using it and, therefore, can help optimize the care of patients with MBC. A detailed analysis of self-identified practice trends among those using the online tool, along with a comparison of expert and participating oncologist treatment choices for different MBC case scenarios, will be presented.

MBC Case ScenarioMajority Consensus Recommendation Among Experts, %Tool Cases Where Oncologist Intended Treatment Matched the Expert Consensus Recommendation, %HR+/HER2- (no visceral crisis)•De novoPalbociclib + letrozole: 10023•Previous (neo)adjuvant AIPalbociclib + fulvestrant: 9219•Previous palbociclib + letrozoleFulvestrant: 820•Previous palbociclib + fulvestrantEverolimus + exemestane: 8750HR-/HER2+•De novoTHP: 10068•Previous pertuzumabT-DM1: 10066Triple-negative breast cancer•Visceral crisisCombination CT: 9139•No visceral crisis, fast progressionSingle-agent CT: 7250AI, aromatase inhibitor; CT, chemotherapy.

Citation Format: Quill TA, Blackwell KL, Hurvitz S, Miller KD, Robert N, Obholz KL, Jahanzeb M. Variance between experts and community practitioners in treatment of metastatic breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-16-02.

Abstract PD3-12: PIK3CA alterations and benefit with neratinib after trastuzumab-based adjuvant therapy in early-stage HER2+ breast cancer: Correlative analyses of the phase III ExteNET trial

Background: Neratinib is a pan-HER tyrosine kinase inhibitor that blocks the PI3K/Akt and MAPK signaling pathways downstream from HER2. The international, randomized, placebo-controlled phase III ExteNET trial showed that a 1-year course of neratinib after trastuzumab-based adjuvant therapy significantly improved 2-year invasive disease-free survival (iDFS) in early-stage HER2+ breast cancer (HR 0.67; 95% CI 0.50–0.91; p=0.0091) [Chan et al. Lancet Oncol 2016]. Furthermore, the effects of neratinib on iDFS were shown to be durable at 5 years' follow-up (HR 0.73; 95% CI 0.57–0.92; p=0.008) [Martin et al. ESMO 2017]. PIK3CA alterations are common in HER2+ breast cancers, and in general are associated with a worse prognosis. We sought to assess the prognostic and predictive significance of PIK3CA alterations in an exploratory substudy of the ExteNET trial.

Methods: ExteNET is an international, multi-center, randomized, double-blind, placebo-controlled phase III trial (Clinicaltrials.gov: NCT00878709). Patients received oral neratinib 240 mg/day or placebo for 1 year. Of the intent-to-treat (ITT) population (n=2840), primary formalin-fixed paraffin-embedded (FFPE) tumor specimens were available from 991 patients for PIK3CA mutation testing by RT-PCR for two hot-spot mutations in exon 9 (E542K, E545K/D) and one hot-spot mutation in exon 20 (H1047R). 702 FFPE tumor slides underwent FISH analysis for PIK3CA amplification with a ratio of ≥2.2 considered as amplified. Primary endpoint: iDFS. iDFS events were tested by 2-sided log-rank tests, and HR (95% CI) were estimated using Cox proportional-hazards models. Data cut-off: March 2017.

Results: Baseline demographics and disease characteristics between treatment arms of the correlative cohort (n=1201) were balanced. Overall, 21.2% (n=210) of primary tumors harbored one of the specified PIK3CA mutations, and 8.7% (n=61) were PIK3CA FISH-amplified. Patients with PIK3CA-altered tumors (i.e. PIK3CA mutations or FISH-amplified) had fewer iDFS events with neratinib compared with placebo (HR 0.41; 95% CI 0.17-0.90, p=0.028). The interaction test was not significant (p=0.1842). Results of the various correlative analyses within treatment arms are shown in the table.

 NeratinibPlacebo   iDFS iDFS 2-sidedPopulationnevents, nnevents, nHR (95% CI)P valueaITT142011614201630.73 (0.57–0.92)b0.008bCorrelative cohort59345608700.67 (0.45–0.96)0.0317PIK3CA-mutation positive1047106170.43 (0.17–1.01)0.056PIK3CA-mutation negative38527396420.66 (0.40-1.06)0.089PIK3CA-amplified3312840.20 (0.01-1.33)0.106PIK3CA-non-amplified31629325360.85 (0.52-1.39)0.521PIK3CA-altered1308132200.41 (0.17-0.90)0.028a. Log-rank test; b. Stratified analysis

Conclusions: One year of neratinib treatment after trastuzumab-based adjuvant therapy significantly improves iDFS after 5 years in patients with early-stage HER2+ breast cancer. From this modest-sized exploratory cohort, it appears that PIK3CA may be a biomarker for differential sensitivity to neratinib after 1 year of trastuzumab in the adjuvant setting.These exploratory results should be validated in a larger subset.

Citation Format: Chia SKL, Martin M, Holmes FA, Ejlertsen B, Delaloge S, Moy B, Iwata H, von Minckwitz G, Mansi J, Barrios CH, Gnant M, Tomašević Z, Denduluri N, Šeparović R, Kim S-B, Hugger Jakobsen E, Harvey V, Robert N, Smith II J, Harker G, Lalani AS, Zhang B, Eli LD, Buyse M, Chan A. PIK3CA alterations and benefit with neratinib after trastuzumab-based adjuvant therapy in early-stage HER2+ breast cancer: Correlative analyses of the phase III ExteNET trial [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD3-12.

HER2 Gene Amplification Testing by Fluorescent In Situ Hybridization (FISH): Comparison of the ASCO-College of American Pathologists Guidelines With FISH Scores Used for Enrollment in Breast Cancer International Research Group Clinical Trials

Purpose

ASCO and the College of American Pathologists (ASCO-CAP) recently recommended further changes to the evaluation of human epidermal growth factor receptor 2 gene (HER2) amplification by fluorescent in situ hybridization (FISH). We retrospectively assessed the impact of these new guidelines by using annotated Breast Cancer International Research Group (BCIRG) -005, BCIRG-006, and BCIRG-007 clinical trials data for which we have detailed outcomes.

Patients and Methods

The HER2 FISH status of BCIRG-005/006/007 patients with breast cancers was re-evaluated according to current ASCO-CAP guidelines, which designates five different groups according to HER2 FISH ratio and average HER2 gene copy number per tumor cell: group 1 (in situ hybridization [ISH]–positive): HER2-to-chromosome 17 centromere ratio ≥ 2.0, average HER2 copies ≥ 4.0; group 2 (ISH-positive): ratio ≥ 2.0, copies < 4.0; group 3 (ISH-positive): ratio < 2.0, copies ≥ 6.0; group 4 (ISH-equivocal): ratio < 2.0, copies ≥ 4.0 and < 6.0; and group 5 (ISH-negative): ratio < 2.0, copies < 4.0. We assessed correlations with HER2 protein, clinical outcomes by disease-free survival (DFS) and overall survival (OS) and benefit from trastuzumab therapy (hazard ratio [HR]).

Results

Among 10,468 patients with breast cancers who were successfully screened for trial entry, 40.8% were in ASCO-CAP ISH group 1, 0.7% in group 2; 0.5% in group 3, 4.1% in group 4, and 53.9% in group 5. Distributions were similar in screened compared with accrued subpopulations. Among accrued patients, FISH group 1 breast cancers were strongly correlated with immunohistochemistry 3+ status (P < .0001), whereas groups 2, 3, 4, and 5 were not; however, groups 2, 4 and, 5 were strongly correlated with immunohistochemistry 0/1+ status (all P < .0001), whereas group 3 was not. Among patients accrued to BCIRG-005, group 4 was not associated with significantly worse DFS or OS compared with group 5. Among patients accrued to BCIRG-006, only group 1 showed a significant benefit from trastuzumab therapy (DFS HR, 0.71; 95% CI, 0.60 to 0.83; P < .0001; OS HR, 0.69; 95% CI, 0.55 to 0.85; P = .0006), whereas group 2 did not.

Conclusion

Our findings support the original categorizations of HER2 by FISH status in BCIRG/Translational Research in Oncology trials.

Abstract 5656: Quantitative measurement of PDL1 expression across tumor types using laser capture microdissection and reverse phase protein microarray

Background: The efficacy of immunotherapy, including therapeutic strategies capable of modulating innate/adaptive immune resistance, varies greatly across tumor types. As the number of available immunotherapies accelerates, the study of predictive markers by IHC (e.g. PDL1 expression) is under intense investigation. However, staining protocol inconsistency, variation across scoring systems, and subjective interpretation of the immunostaining have produced conflicting results thus far. This work explored the role of Laser Capture Microdissection (LCM) coupled with Reverse Phase Protein Microarray (RPPA) as an alternative high throughput, quantitative, operator independent platform for measuring PDL1 expression across tumor types.

Material and Methods: Pure epithelial cells were isolated via LCM from 178 samples including: 72 ovarian cancers (OC), 57 lung adenocarcinomas (LC), 30 metastatic breast cancers (MBC), and 19 pancreatic cancers (PC). PDL1 expression was measured on a continuous scale using quantitative RPPA based analysis. Each tumor type was processed and arrayed independently. Experimental samples and reference standards used for inter-assay normalization were printed in triplicates.

Results: PDL1 expression varied greatly across tumor types. LC were characterized by the greatest intra-tumor fold dynamic range (&gt; 35-fold), followed by OC (&lt; 13-fold), MBC (&lt; 4-fold), and PC (&lt; 2-fold). PDL1 expression of 46/57 (80.7%) LC, 17/30 (56.7%) MBC, 6/19 (31.5%) PC, and 20/72 (27.8%) OC was greater than the population median of all tumors combined. Within the LC samples with PDL1 expression equal to the top quartile of the population, 10 (71.4%) were KRAS mutant lesions and 4 (28.6%) were WT tumors. Finally, amongst LC and PC harboring a KRAS mutation, PC showed an overall lower expression of PDL1 with only 2/19 (10.5%) cases been above the population median and none within the top quartile of the population.

Conclusions: The LCM-RPPA workflow has the unique ability to capture immune checkpoint expression on a continuous quantitative scale as well as capture its broad dynamic range. Because RPPA is unconstrained by antigen retrieval issues as well as subjectivity of IHC interpretation, this approach may generate more accurate cut-point of therapeutic response prediction. Overall the dynamic range of PDL1 was broader in LC compared to other solid tumors, and LC had a much higher proportion of patients with tumors expressing high levels of PDL1. These quantitative differences may explain therapeutic efficacy of PDL1 inhibition across tumor types. Such speculative hypothesis should be further validated in prospective clinical trials. Finally, these preliminary data suggest that organ specific microenvironments more than specific driving mutations (e.g. KRAS) may strongly influence PDL1 expression in malignant lesions.

Citation Format: Elisa Baldelli, Valerie Calvert, K. Alex Hodge, Maria Isabella Sereni, Guido Gambara, Eric B. Haura, Lucio Crino', Bryant Dunetz, Sergio Pecorelli, David J. Perry, Stephen P. Anthony, Nicholas Robert, Donald W. Northfelt, Mohammad Jahanzeb, Emanuel F. Petricoin, Mariaelena Pierobon. Quantitative measurement of PDL1 expression across tumor types using laser capture microdissection and reverse phase protein microarray [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5656. doi:10.1158/1538-7445.AM2017-5656

Abstract P1-07-09: A multi-OMIC analysis to explore the impact of “actionable” genomic alterations on protein pathway activation: Clinical implication for precision medicine in metastatic breast cancer

Background: While genomic alterations are central players in tumor progression, proteins are the targets for precision therapy. The degree by which “actionable” genomic alterations translate into activated/altered proteins and pathway is still under investigation. Using a multi-OMIC approach from the SideOut 2 metastatic breast cancer (MBC) trial, this study explored the concordance between selected “actionable” genomic alterations and protein expression/activation.

Methods: Snap frozen biopsies from 29 MBC patients enrolled in a prospective phase II trial were used for this analysis. Exome WES and RNASeq data was processed using an in-house developed pipeline and identified amplification of CCND1 (6/29), FGFR1 (4/29), and FGF 3, 4, 5, and 19 (4/29) as some of most frequent “actionable” genomic alterations in our MBC cohort. Signaling analysis of the 29 cases was performed using Reverse Phase Protein Microarray coupled with Laser Capture Microdissection. Protein expression/phosphorylation was measured in a continuous scale and classified based on quartile distribution. Concordance between CCND1 amplification and Cyclin D1 expression, along with the activation of FOXM1 T600 and Rb S780, was explored. Amplification of the FGFR1 locus or its ligands was correlated with the level of activation/phosphorylation of FGFR1 Y653/654.

Results: While Cyclin D1 protein expression was greater than the population mean for 4/6 (67%) patients with CCND1 amplification, only 2/6 (33%) patients with CCND1 amplification had Cyclin D1 level within the top quartile of the population (n=29). FOXM1 T600 activation was independent from CCND1 amplification, with high levels of FOXM1 T600 predominantly in the CCND1 wild-type population. Only 1/6 (17%) patients with CCND1 amplification had FOXM1 T600 level similar to the top quartile of the population while a second patient was above the population median. Activation of Rb S780 was above the population median, but below the top quartile, in 2/6 (33%) CCND1 amplified patients. Similarly, none of the patients with activation of FGFR Y653/654 equal to the top quartile harbored an FGFR1 amplification. Only 1/4 (25%) patients carrying an FGFR1 amplification had an activation of FGFR Y653/654 above the population median. Similarly, 1/4 (25%) patients with FGF ligand amplification showed FGFR Y653/654 level within the top quartile while three patients had FGFR Y653/654 activation below the population median. No significant results were found between proteomic (below/above the median) and genomic characteristics by Fisher test (p&gt;0.05).

Conclusion: Molecular genotyping of “actionable” cancer targets alone may be insufficient in predicting whether the actual drug target protein is expressed and/or activated in any given patient's tumor. Although these results need further validation, the combination of genomic and proteomic data may represent a more informative approach for identifying real molecular drivers of individual lesions as well as “actionable” protein/phosphoprotein targets in the absence of genomic events. Multi-OMIC approaches may lead to more effective stratification in precision medicine trials.

Citation Format: Pierobon M, Wong S, Reeded A, Anthony S, Robert N, Northfelt DW, Jahanzeb M, Vocila L, Wulfkuhle J, Dunetz B, Aldrich J, Byron S, Craig D, Liotta L, Carpten J, Petricoin EF. A multi-OMIC analysis to explore the impact of “actionable” genomic alterations on protein pathway activation: Clinical implication for precision medicine in metastatic breast cancer [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 P1-07-09.

A Mixed Epithelial and Stromal Tumor of the Kidney in a Ringtail Lemur (Lemur catta)

Primary renal tumors are rare neoplasms in nonhuman primates. This report describes a mixed epithelial and stromal tumor of the kidney (MESTK) in a 14.5-year-old female ringtail lemur. The well-demarcated, solid, and cystic mass was located in the pelvis of the left kidney and consisted histologically of both epithelial and mesenchymal components. The mesenchymal cells were arranged in fascicles around cysts lined by a well-differentiated epithelium. Neither the mesenchymal nor the epithelial parts showed significant nuclear atypia or mitotic figures. To our knowledge, only 1 similar case, classified as adenoleiomyofibromatous hamartoma, has been reported in a ringtail lemur. In humans this tumor affects predominantly perimenopausal women and can express estrogen and progesterone receptors. However, neither estrogen nor progesterone receptors could be identified by immunohistochemistry in the tumor of the present ringtail lemur. Therefore, a hormonal mechanism could not be demonstrated in this case.

Challenges With Research Contract Negotiations in Community-Based Cancer Research

Purpose:

Community-based research programs face many barriers to participation in clinical trials. Although the majority of people with cancer are diagnosed and treated in the community setting, only roughly 3% are enrolled onto clinical trials. Research contract and budget negotiations have been consistently identified as time consuming and a barrier to participation in clinical trials. ASCO’s Community Research Forum conducted a survey about specific challenges of research contract and budget negotiation processes in community-based research settings. The goal was to ultimately identify potential solutions to these barriers.

Methods:

A survey was distributed to 780 community-based physician investigators and research staff. The survey included questions to provide insight into contract and budget negotiation processes and perceptions about related barriers.

Results:

A total of 77% of the 150 respondents acknowledged barriers in the process. Respondents most frequently identified budget-related issues (n = 133), inefficiencies in the process (n = 80), or legal review and negotiation issues (n = 70). Of the respondents, 44.1% indicated that contract research organizations made the contract negotiations process harder for their research program, and only 5% believed contract research organizations made the process easier. The contract negotiations process is perceived to be impeded by sponsors through underestimation of costs, lack of flexibility with the contract language, and excessive delays.

Conclusion:

Improving clinical trial activation processes and reducing inefficiencies would be beneficial to all interested stakeholders, including patients who may ultimately stand to benefit from participation in clinical trials. The following key recommendations were made: standardization of contracts and negotiation processes to promulgate transparency and efficiencies, improve sponsor processes to minimize burden on sites, create and promote use of contract templates and best practices, and provide education and consultation.

Assessing Clinical Trial-Associated Workload in Community-Based Research Programs Using the ASCO Clinical Trial Workload Assessment Tool

PURPOSE

Clinical research program managers are regularly faced with the quandary of determining how much of a workload research staff members can manage while they balance clinical practice and still achieve clinical trial accrual goals, maintain data quality and protocol compliance, and stay within budget. A tool was developed to measure clinical trial-associated workload, to apply objective metrics toward documentation of work, and to provide clearer insight to better meet clinical research program challenges and aid in balancing staff workloads. A project was conducted to assess the feasibility and utility of using this tool in diverse research settings.

METHODS

Community-based research programs were recruited to collect and enter clinical trial-associated monthly workload data into a web-based tool for 6 consecutive months. Descriptive statistics were computed for self-reported program characteristics and workload data, including staff acuity scores and number of patient encounters.

RESULTS

Fifty-one research programs that represented 30 states participated. Median staff acuity scores were highest for staff with patients enrolled in studies and receiving treatment, relative to staff with patients in follow-up status. Treatment trials typically resulted in higher median staff acuity, relative to cancer control, observational/registry, and prevention trials. Industry trials exhibited higher median staff acuity scores than trials sponsored by the National Institutes of Health/National Cancer Institute, academic institutions, or others.

CONCLUSION

The results from this project demonstrate that trial-specific acuity measurement is a better measure of workload than simply counting the number of patients. The tool was shown to be feasible and useable in diverse community-based research settings.

Abstract P4-14-13: Pertuzumab (P) use in first-line HER2-positive metastatic breast cancer (mBC) in US community oncology practices: Treatment patterns and outcomes

Background: Pertuzumab was FDA-approved in 6/2012 for use in first-line in combination with trastuzumab (H) and docetaxel for patients (pts) with HER2-positive mBC. This retrospective study investigated the clinical characteristics, treatment patterns, safety, and outcomes for pts with HER2-positive mBC who received a P-containing regimen in first-line in US community oncology practices.

Methods: This study utilized iKnowMed electronic health records, Claims Data Warehouse, and Social Security Death Index. Pts with HER2-positive mBC, who received a P-containing regimen between 6/2012 and 6/2014 and were followed through 12/2014, had ≥2 visits within the McKesson Specialty Health/US Oncology Network, and were not on clinical trials during the study period, were eligible.

Results: Of the 322 pts who received a P-containing regimen in the first-line setting, 25% were ≥65 years of age, 63% were post-menopausal, 61% had hormone receptor-positive mBC, 84% had a performance status of 0 or 1, and 76% had a Charlson Comorbidities Index of 0. Twenty-one percent of pts had 1 site of metastasis noted, 32% had 2 sites, and 47% had 3 or more sites. Pts with de novo mBC made up 40% of this cohort. Of the pts with recurrent mBC, over 60% received H in the early-stage BC setting. In the first-line mBC setting, 93% of the 322 pts received H+P+taxane, and 7% received H+P with other chemotherapy agent(s). Common adverse events reported included: fatigue (49%), diarrhea (44%), nausea (33%), peripheral neuropathy (33%), neutropenia (24%), and rash (22%). Further analyses including outcomes of these 322 pts will be presented.

Conclusions: First-line P was given in combination with H and chemotherapy agent(s) (93% taxane). No new safety signals were observed. More details on the clinical characteristics, specific treatment patterns, and safety will be presented, along with the progression-free survival of these pts receiving first-line P-containing therapy in a real-world setting.

Citation Format: Robert N, Goertz H-P, Asmar L, Tseng W-Y, Jiao X, Portera C, Yoo B, Patt D, Antao V. Pertuzumab (P) use in first-line HER2-positive metastatic breast cancer (mBC) in US community oncology practices: Treatment patterns and outcomes. [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 P4-14-13.

PTEN Loss Is Associated with Worse Outcome in HER2-Amplified Breast Cancer Patients but Is Not Associated with Trastuzumab Resistance

PURPOSE

To investigate the clinical relevance of PTEN in HER2-amplified and HER2-nonamplified disease.

EXPERIMENTAL DESIGN

We assessed PTEN status in two large adjuvant breast cancer trials (BCIRG-006 and BCIRG-005) using a PTEN immunohistochemical (IHC) assay that was previously validated in a panel of 33 breast cancer cell lines and prostate cancer tissues with known PTEN gene deletion.

RESULTS

In the HER2-positive patient population, absence of tumor cell PTEN staining occurred at a rate of 5.4% and was independent of ER/PR status. In contrast, 15.9% of HER2-negative patients exhibited absence of PTEN staining with the highest frequency seen in triple-negative breast cancer (TNBC) subgroup versus ER/PR-positive patients (35.1% vs. 10.9%). Complete absence of PTEN staining in tumor cells was associated with poor clinical outcome in HER2-positive disease. Those patients whose cancers demonstrated absent PTEN staining had a significant decrease in disease-free survival (DFS) and overall survival (OS) compared with patients with tumors exhibiting any PTEN staining patterns (low, moderate, or high). Trastuzumab appeared to provide clinical benefit even for patients lacking PTEN staining. In the HER2-negative population, there were no statistically significant differences in clinical outcome based on PTEN status.

CONCLUSIONS

This study is the largest to date examining PTEN status in breast cancer and the data suggest that the rate and significance of PTEN status differ between HER2-positive and HER2-negative disease. Furthermore, the data clearly suggest that HER2-positive patients with PTEN loss still benefit from trastuzumab.