Very APBI in 1 or 2 Days: Late Toxicity and Early Oncological Outcomes of the GEC-ESTRO Cohort

PURPOSE/OBJECTIVE(S)

To analyze late toxicity after very accelerated partial breast irradiation (VAPBI) for low-risk breast cancer.

MATERIALS/METHODS

In this retrospective observational international multicenter study (HDH F20220713143949) from 7 European centers, patients with low-risk breast cancer underwent lumpectomy + adjuvant VAPBI based on high-dose rate (HDR) multicatheter interstitial brachytherapy (MIB). VAPBI was performed with 4 (4 × 6.2 Gy/2 d), 3 (3 × 7.45 Gy/2 d) or 1 fraction (1 × 16 Gy or 1 × 18 Gy/1 d). Primary endpoint was late toxicity. Secondary endpoints were oncological outcome based on cumulative incidence of breast cancer local relapse (LR) and distant metastasis disease (DMD) and cause-specific (CSS) and overall (OS) survival. Prognostic factors for late toxicity were analyzed.

RESULTS

From 01/2012 to 06/2022, the GEC-ESTRO VAPBI cohort included 516 pts with an early breast cancer. Median follow-up was 42 months [95% CI = 39 - 44]. Median age was 71 years [40 - 100]. Median tumor size was 12 mm [1 - 46]. Tumor was mainly invasive ductal carcinoma (78%), pN0 (88.5%), with positive hormonal receptors (98.5%) and negative HER2 overexpression (96%). Patients underwent hormonal and chemo-therapy in 93.8% and 2.3% respectively. Catheter placement was performed peri or post-operatively in 50.2% and 49.8% respectively. Median time interval between surgery and VABPI was 10 days [6 - 65]. VAPBI delivered 1, 3 and 4 fractions for 205 pts (39.7%), 167 pts (32.4%) and 144 pts (28%) respectively. Median CTV was 40.7 cc [95% CI = 26.6 - 72], median V100%, V150%, D90% and Dose non-uniformity ratio (DNR) were 90.2% [95% CI = 84.1 - 97.2], 24.2% [95% CI = 18.9 - 31.6], 103.8% [95% CI = 100.1 - 107.4] and 0.28 [95% CI = 0.23 - 0.33] respectively, 211 late toxicity events were observed in 168 pts (32.6%). Fibrosis, dyschromia, pain and telangiectasia were observed in 26.7%, 7.9%, 7.2% and 0.4 respectively. Grade 2 and 3 late toxicities were observed in 7.2 and 0.6% respectively (no G4). Grade ≥2 late toxicity was observed in 8.1%, 16.7% and 3.7% after 1, 3 and 4 fractions, respectively (p = 0.004). CTV > 50 cc (p = 0.007) and V150 > 40% (p = 0.027) were prognostic factors for G≥2 late toxicity. Regarding oncological outcome, 4-year cumulative incidence of LR, RR and DMD were 2% [95% CI = 0 - 3], 1% [95% CI = 0 - 2] and 1% [95% CI = 0 - 2] respectively. CSS and OS were 98% [95% CI = 96 - 100] and 93% [95% CI = 90 - 96] respectively. No significant difference was observed in terms of oncological outcome between the 3-fractionation groups.

CONCLUSION

VAPBI based on 1 or 2 days of HDR MIB represents an attractive de-escalation irradiation approach for low-risk breast cancer. Late toxicity profile appears acceptable while early oncological outcome shows excellent local control. Brachytherapy technique remains a key component of clinical outcome. Longer follow-up is warranted in order to confirm these encouraging preliminary results.

SF3B1 mutation and ATM deletion codrive leukemogenesis via centromeric R-loop dysregulation

RNA splicing factor SF3B1 is recurrently mutated in various cancers, particularly in hematologic malignancies. We previously reported that coexpression of Sf3b1 mutation and Atm deletion in B cells, but not either lesion alone, leads to the onset of chronic lymphocytic leukemia (CLL) with CLL cells harboring chromosome amplification. However, the exact role of Sf3b1 mutation and Atm deletion in chromosomal instability (CIN) remains unclear. Here, we demonstrated that SF3B1 mutation promotes centromeric R-loop (cen-R-loop) accumulation, leading to increased chromosome oscillation, impaired chromosome segregation, altered spindle architecture, and aneuploidy, which could be alleviated by removal of cen-R-loop and exaggerated by deletion of ATM. Aberrant splicing of key genes involved in R-loop processing underlay augmentation of cen-R-loop, as overexpression of the normal isoform, but not the altered form, mitigated mitotic stress in SF3B1-mutant cells. Our study identifies a critical role of splice variants in linking RNA splicing dysregulation and CIN and highlights cen-R-loop augmentation as a key mechanism for leukemogenesis.

Autologous Stem Cell Transplant in Lymphoma Using a Noncryopreserved Platform: An Adapted Sequential Conditioning Maintaining Dose Intensity Does not Affect Transplantation Outcomes

BACKGROUND

Hematopoietic autologous stem cell transplantation (ASCT) is a validated therapeutic strategy for lymphoma treatment and precise well-tolerated conditioning. Several conditioning methods are available, but the most commonly used are CVB, BEAM, and ICE, which are conventionally administered in 6 to 7 days. Since 2015, our program has moved toward noncryopreserved platforms that require concise times; therefore, we have modified the conditioning by reducing it to 4 to 5 days. In this study, we show our experience.

METHODS

We compared ASCT performed in our program before and after 2015 in lymphoma patients. Between 2000 and 2014 and from 2015 to 2022, we performed 46 and 61 ASCT procedures, respectively.

RESULTS

Since 2015, we observed a greater number of infused stem cells, fewer episodes of febrile neutropenia (60% vs. 37% P = .008), shorter hospitalizations (30 vs. 18 days P = .001), faster engraftment (20 vs. 14 days P = .001) and better progression-free survival (72 vs. 44 months P = .002). Additionally, a prolonged overall survival was observed at these results, and this prolonged survival is difficult to interpret due to the short follow-up.

CONCLUSION

In conclusion, conditioning adjusted for a noncryopreserved strategy offers at least similar or even better results than the cryopreserved strategy. Prospective studies are warranted.

The Prevalence and Prognosis of Microsatellite Instability-High/Mismatch Repair-Deficient Colorectal Adenocarcinomas in the United States

PURPOSE

Microsatellite instability (MSI) and DNA mismatch repair (MMR) status is an indispensable biomarker in the management of colorectal cancers. We therefore examined the epidemiology of MSI-high/MMR-deficient colorectal cancers in the United States.

METHODS

Adults presenting with colorectal adenocarcinoma in 2018-2019 were identified from the US National Cancer Database. Attributes associated with MSI-high/MMR-deficiency were identified using multivariable logistic regression and reported using average adjusted probabilities (%AAP) and 99.9% CIs. As a secondary aim, the survival associated with MSI/MMR status was assessed.

RESULTS

Among 101,259 colorectal adenocarcinomas in 2018-2019, 82.0% were microsatellite stable/MMR-proficient, 3.8% MSI-low, and 14.2% MSI-high/MMR-deficient-including 16.6%, 19.9%, 12.4%, and 7.3% of stage I, II, III, and IV cancers, respectively. In locoregional cancers, MSI-high/MMR-deficiency was associated with a bimodal age distribution, female sex, right-sided colonic origin, wild-type KRAS, and a prior diagnosis of cancer (all P < .001). By race/ethnicity, colorectal adenocarcinomas were MSI-high/MMR-deficient in 16.9%AAP of non-Hispanic White (99.9% CI, 16.5 to 17.4) patients, compared with 11.3%AAP of non-Hispanic Black (99.9% CI, 10.3 to 12.4), 12.4%AAP of Asian/Pacific Islander (99.9% CI, 10.5 to 14.3), and 15.1%AAP of Hispanic (99.9% CI, 13.4 to 16.7) patients (all P < .001). Histologically, MSI-high/MMR-deficiency was associated with increasing grade, from 11.3%AAP of well-differentiated tumors (99.9% CI, 10.2 to 12.4) to 28.4%AAP of poorly differentiated cases (99.9% CI, 27.1 to 29.8; P < .001). Compared with conventional histology (15.2%AAP, 99.9% CI, 14.8 to 15.6), medullary (41.1%AAP, 99.9% CI, 33.0 to 49.3; P < .001) and mucinous (24.6%AAP, 99.9% CI, 22.8 to 26.3; P < .001) subtypes-but not signet-ring cell histology (15.5%AAP, 99.9% CI, 11.6 to 19.4; P = .79)-were more frequently MSI-high/MMR-deficient when adjusting for clinicopathologic features including grade.

CONCLUSION

Our findings establish the epidemiology, features, and prognostic implications of MSI-high/MMR-deficiency among colorectal adenocarcinoma patients in the United States.

Impact of STK11 copy loss on clinical outcomes to PD-(L)1 blockade in non–small cell lung cancer

9059

Background: STK11 is among the most commonly altered genes in non-squamous lung cancers. While STK11 mutation is associated with diminished efficacy of immune checkpoint inhibition (ICI), particularly in KRAS mutated tumors, it is not known whether STK11 copy deletion influences outcomes to ICI. Methods: Patients with advanced non-squamous non-small cell lung cancer (NSCLC) treated with ICI whose tumors underwent genomic profiling were included. Clinical outcomes to ICI were analyzed according to KRAS mutation and STK11 deletions. STK11 copy number variations (CNVs) were determined using an internal informatic pipeline. Kaplan-Meier methodology was used to estimate event-time distributions. Results: Of 559 patients with non-squamous NSCLCs (Nsq-NSCLC), 40.4% (N = 226) had a KRAS mutation ( KRASmut), 18.4% (N = 103) had an oncogenic STK11 mutation ( STK11mut), and 22.5% had either single (N = 123), or bi-allelic (N = 3) deletion ( STK11del). Given that 32.5% of STK11del cases had a concurrent oncogenic STK11 mutation in our cohort, to isolate the impact of STK11del on ICI outcomes we excluded samples with STK11mut from this analysis. In all comers with NSCLC, STK11del had no impact on objective response rate (22.2% versus 23.8%, P = 0.8), progression-free (PFS, HR 0.90, P = 0.30), and overall survival (OS, HR 0.96, P = 0.79) to ICI. When we examined the impact of STK11del on clinical outcomes to PD-(L)1 blockade among KRASmut cases we found that STK11del was associated with a numerically lower ORR (13.3% versus 30.0%, P = 0.12), and a significantly shorter PFS (HR 0.57, P = 0.018) compared to cases without STK11del. No difference in OS were observed between these groups (HR 0.77, P = 0.39). Among KRASwt NSCLCs, STK11del cases had a similar ORR (22.6% versus 22.9%, P = 0.99), PFS (HR 0.92, P = 0.63), and OS (HR 1.18, P = 0.32) to PD-(L)1 inhibition compared to cases without STK11del. Among KRASmut but not KRASwt NSCLCs, cases with STK11del had significantly lower PD-L1 expression compared to those without STK11 deletions (27.5% versus 70%, P = 0.01). Conclusions: STK11 deletion is associated with low response rate and short progression-free survival among KRAS mutant NSCLCs. Future analyses will incorporate additional cases to increase sample size and immunopathologic findings to assess impact of mono and bi-allelic deletion on protein expression.

Functionalized Lineage Tracing Can Enable the Development of Homogenization-Based Therapeutic Strategies in Cancer

The therapeutic landscape across many cancers has dramatically improved since the introduction of potent targeted agents and immunotherapy. Nonetheless, success of these approaches is too often challenged by the emergence of therapeutic resistance, fueled by intratumoral heterogeneity and the immense evolutionary capacity inherent to cancers. To date, therapeutic strategies have attempted to outpace the evolutionary tempo of cancer but frequently fail, resulting in lack of tumor response and/or relapse. This realization motivates the development of novel therapeutic approaches which constrain evolutionary capacity by reducing the degree of intratumoral heterogeneity prior to treatment. Systematic development of such approaches first requires the ability to comprehensively characterize heterogeneous populations over the course of a perturbation, such as cancer treatment. Within this context, recent advances in functionalized lineage tracing approaches now afford the opportunity to efficiently measure multimodal features of clones within a tumor at single cell resolution, enabling the linkage of these features to clonal fitness over the course of tumor progression and treatment. Collectively, these measurements provide insights into the dynamic and heterogeneous nature of tumors and can thus guide the design of homogenization strategies which aim to funnel heterogeneous cancer cells into known, targetable phenotypic states. We anticipate the development of homogenization therapeutic strategies to better allow for cancer eradication and improved clinical outcomes.

Molecular Biomarker-Defined Brain Tumors: Epidemiology, Validity, and Completeness in the United States

BACKGROUND

Selected molecular biomarkers were incorporated into U.S. cancer registry reporting for patients with brain tumors beginning in 2018. We investigated the completeness and validity of these variables, and described the epidemiology of molecularly-defined brain tumor types.

METHODS

Brain tumor patients with histopathologically-confirmed diagnosis in 2018 were identified within the Central Brain Tumor Registry of the United States and NCI's Surveillance, Epidemiology, and End Results Incidence databases. The brain molecular markers (BMM) site-specific data item was assessed for coding completeness and validity. 1p/19q status, MGMT promoter methylation, and WHO grade data items, and new ICD-O-3 codes were additionally evaluated. These data were used to profile the characteristics and age-adjusted incidence rates per 100,000 population of molecularly-defined brain tumors with 95% confidence intervals (95%CI).

RESULTS

BMM completeness across the applicable tumor types was 75-92% and demonstrated favorable coding validity. IDH-wildtype glioblastomas' incidence rate was 1.74 (95%CI: 1.69-1.78), as compared to 0.14 for WHO grade 2 (95%CI: 0.12-0.15), 0.15 for grade 3 (95%CI: 0.14-0.16), and 0.07 for grade 4 (95%CI: 0.06-0.08) IDH-mutant astrocytomas. Irrespective of WHO grade, IDH mutation prevalence was highest in adolescent & young adult patients and IDH-mutant astrocytomas were more frequently MGMT promoter methylated. Among pediatric-type tumors, the incidence rate was 0.06 for H3K27M-mutant diffuse midline gliomas (95%CI: 0.05-0.07), 0.03 for SHH-activated/TP53-wildtype medulloblastomas (95%CI: 0.02-0.03), and <0.01 for both C19MC-altered ETMRs and RELA-fusion ependymomas.

CONCLUSIONS

Our findings illustrate the success of developing a dedicated, integrated-diagnosis variable, which provides critical molecular information about brain tumors related to accurate diagnosis.

Epidemiology of common and uncommon adult pituitary tumors in the U.S. according to the 2017 World Health Organization classification

PURPOSE

To examine the contemporary epidemiology of adult pituitary tumors with a particular focus on uncommon tumor types, using the 2017 WHO Classification of pituitary tumors.

METHODS

Adult patients presenting with a pituitary or sellar tumor between 2004 and 2017 were identified from the U.S. National Cancer Database, with tumor type categorized according to the 2017 WHO classification. Descriptive epidemiological statistics were evaluated and reported for all pituitary tumor types and subtypes.

RESULTS

113,349 adults with pituitary tumors were identified, 53.0% of whom were female. The majority of pituitary tumors were pituitary adenomas (94.0%), followed by craniopharyngiomas (3.8%). Among pituitary adenomas, whereas 71.6% of microadenomas presented in females, only 46.7% of macroadenomas and 41.3% of giant adenomas did (p < 0.001). For craniopharyngiomas, 71.2% were adamantinomatous and 28.8% were papillary, with adamantinomatous tumors associated with Black non-Hispanic race/ethnicity (OR_adj = 2.44 vs. White non-Hispanic, 99.9 %CI = 1.25-4.75, p < 0.001) in multivariable analysis. The remaining 0.7% (n = 676) of pathology-confirmed pituitary tumor types were composed of: 21% tumors of the posterior pituitary, 16% chordomas, 11% pituitary carcinomas (i.e. adenohypophyseal histology with metastasis; herein most frequently to bone), 10% meningiomas, 8% germ cell tumors, 7% hematolymphoid (largely DLBCLs), and 4% neuronal/paraneuronal (largely gangliogliomas). Pituitary carcinomas and posterior pituitary tumors demonstrated a male predilection (62.2% and 56.0%, respectively), whereas sellar meningiomas predominated in females (84.1%). Age, race/ethnicity, tumor size, and overall survival further varied across uncommon pituitary tumor types.

CONCLUSIONS

Our findings provide a detailed contemporary dissection of the epidemiology of common and uncommon adult pituitary tumors in the context of WHO2017.

Activation of Notch and Myc Signaling via B-cell-Restricted Depletion of Dnmt3a Generates a Consistent Murine Model of Chronic Lymphocytic Leukemia

Chronic lymphocytic leukemia (CLL) is characterized by disordered DNA methylation, suggesting these epigenetic changes might play a critical role in disease onset and progression. The methyltransferase DNMT3A is a key regulator of DNA methylation. Although DNMT3A somatic mutations in CLL are rare, we found that low DNMT3A expression is associated with more aggressive disease. A conditional knockout mouse model showed that homozygous depletion of Dnmt3a from B cells results in the development of CLL with 100% penetrance at a median age of onset of 5.3 months, and heterozygous Dnmt3a depletion yields a disease penetrance of 89% with a median onset at 18.5 months, confirming its role as a haploinsufficient tumor suppressor. B1a cells were confirmed as the cell of origin of disease in this model, and Dnmt3a depletion resulted in focal hypomethylation and activation of Notch and Myc signaling. Amplification of chromosome 15 containing the Myc gene was detected in all CLL mice tested, and infiltration of high-Myc-expressing CLL cells in the spleen was observed. Notably, hyperactivation of Notch and Myc signaling was exclusively observed in the Dnmt3a CLL mice, but not in three other CLL mouse models tested (Sf3b1-Atm, Ikzf3, and MDR), and Dnmt3a-depleted CLL were sensitive to pharmacologic inhibition of Notch signaling in vitro and in vivo. Consistent with these findings, human CLL samples with lower DNMT3A expression were more sensitive to Notch inhibition than those with higher DNMT3A expression. Altogether, these results suggest that Dnmt3a depletion induces CLL that is highly dependent on activation of Notch and Myc signaling. SIGNIFICANCE: Loss of DNMT3A expression is a driving event in CLL and is associated with aggressive disease, activation of Notch and Myc signaling, and enhanced sensitivity to Notch inhibition.

EPID-14. EPIDEMIOLOGY OF ADULT PITUITARY TUMORS IN THE U.S. ACCORDING TO THE 2017 WHO CLASSIFICATION OF ENDOCRINOLOGY TUMOURS

INTRODUCTION

Among adult intracranial tumors, the pituitary represents a frequent site of origin. We examine their contemporary epidemiology with a particular focus on uncommon pituitary tumor types.

METHODS

Adult patients presenting with pituitary or sellar tumors between 2004-2017 were identified from the U.S. National Cancer Database (comprising &gt;70% of newly-diagnosed cancers). Their epidemiology was assessed in the context of the 2017 WHO Classification of Endocrine Tumours.

RESULTS

12.5% of adult intracranial tumors arose in the pituitary region. 113,352 adults with pituitary tumors were identified. Histopathological diagnosis was obtained in only 59% of cases, in which 93% were pituitary adenomas and 6% were craniopharyngiomas. Among craniopharyngiomas, 71% were adamantinomatous and 29% were papillary, between which there were no differences in age, sex, or tumor size—however, papillary craniopharyngiomas were less common among Black nonHispanic patients (p&lt; 0.001). Among the remaining 1% (n=680) of pituitary tumors, posterior pituitary tumors comprised 21%, chordomas 16%, meningiomas 15%, pituitary carcinomas 11%, GCTs 10%, hematolymphoid 8%, other mesenchymal and stromal 7%, neuronal/paraneuronal 6%, and schwannoma 4%. Meningiomas (84%), mesenchymal/stromal (64%), and neuronal/paraneuronal (64%) tumors displayed a female predominance, whereas GCTs (75%) and pituitary carcinomas (62%) exhibited a male predominance. Age at diagnosis, tumor size, and race/ethnicity varied widely across uncommon tumor types. We further examined the subtypes of uncommon pituitary tumors: for sellar chordomas, 19% were chordoid and none were dedifferentiated; for sellar meningiomas, 94% were grade I; for pituitary GCTs, 79% were pure germinomas; for hematolymphoid, 52% were DLBCL, 11% were plasmacytomas, and 9% were Langerhans cell histiocytosis; for neuronal/paraneuronal, 64% were gangliocytomas; and for mesenchymal tumors, 53% were vascular and 16% were SFTs/HPCs.

CONCLUSIONS

Using national registry data, we provide a detailed dissection of the epidemiology of adult pituitary tumors, with a particular focus on examining uncommon pituitary tumor types in the context of WHO2017.

Feasible and effective use of a simulation-based curriculum for post-graduate emergency medicine trainees in India to improve learner self-efficacy, knowledge, and skills

BACKGROUND

Pediatric emergency medicine training is in its infancy in India. Simulation provides an educational avenue to equip trainees with the skills to improve pediatric care. We hypothesized that a simulation-based curriculum can improve Indian post-graduate emergency medicine (EM) trainees' self-efficacy, knowledge, and skills in pediatric care.

METHODS

We designed a simulation-based curriculum for management of common pediatric emergencies including sepsis, trauma, and respiratory illness and pediatric-specific procedures including vascular access and airway skills. Training included didactics, procedural skill stations, and simulation. Measures included a self-efficacy survey, knowledge test, skills checklist, and follow-up survey. Results were analyzed using the Wilcoxon signed-rank test and paired-samples t test. A 6-month follow-up survey was done to evaluate lasting effects of the intervention.

RESULTS

Seventy residents from four academic hospitals in India participated. Trainees reported feeling significantly more confident, after training, in performing procedures, and managing pediatric emergencies (p < 0.001). After the simulation-based curriculum, trainees demonstrated an increase in medical knowledge of 19% (p < 0.01) and improvement in procedural skills from baseline to mastery of 18%, 20%, 16%, and 19% for intubation, bag-valve mask ventilation, intravenous access, and intraosseous access respectively (p < 0.01). At 6-month follow-up, self-efficacy in procedural skills and management of pediatric emergencies improved from baseline.

CONCLUSIONS

A simulation-based curriculum is an effective and sustainable way to improve Indian post-graduate EM trainees' self-efficacy, knowledge, and skills in pediatric emergency care.

POS0304 EPIDEMIOLOGY AND ECONOMIC BURDEN ASSOCIATED WITH MENTAL HEALTH COMORBIDITIES IN SYSTEMIC LUPUS ERYTHEMATOSUS AND LUPUS NEPHRITIS PATIENTS

Background:

Systemic lupus erythematosus (SLE), a multisystem autoimmune disease, is associated with mental health (MH) disorders. There is scarce information on the epidemiology and economic burden associated with MH comorbidities and the impact on SLE as well as the subpopulation with lupus nephritis (LN).

Objectives:

Examined the incidence and prevalence rate of MH, healthcare resource utilization (HCRU), and costs associated with MH comorbidities in SLE/LN patients.

Methods:

Adult SLE and LN patients with ≥1 inpatient or ≥2 outpatient diagnosis claims for SLE/LN (ICD-9 code: 710.0; and ICD-10 codes M32.10-19, M32.8, M32.9) were identified between 01JAN2013-30JUN2019 from two large US commercial databases. Inclusion required continuous enrollment benefits 12 months pre-/post-index date. Patients were divided into two groups: those with (WMH) vs. those without (NMH). WMH was defined as a MH diagnosis of depression, anxiety, bipolar disorder, or psychosis. Index date for the WMH group was first MH diagnosis claim. For the NMH group, a random index date was assigned between 01JAN2014-30JUN2018. The groups were then matched with a 1:1 ratio based on age, sex, and region within their respective databases. Incidence and prevalence rate of MH in the SLE/LN population were determined. All-cause healthcare costs and HCRU per patients per year (PPPY) were examined with generalized linear models.

Results:

A total of 7,760 SLE and 336 LN patients were identified. The majority of patients were female (SLE=93.5%; LN=95.2%) with a mean age of 55.1 years (SLE) and 44.5 years (LN). The prevalence rate of MH was 35.7% for SLE and 28.8% for LN patients and the incidence rate was 18.5% and 15.3%, respectively. Anxiety and depression were the most common MH comorbidities (Figure 1). WMH inpatient stays averaged an additional 2.6 and 7.2 days longer than NMH for SLE and LN, respectively. In addition, WMH patients averaged 10.4 (SLE) and 18.4 (LN) significantly more outpatient visits PPPY than NMH. Overall healthcare cost PPPY was significantly higher for WMH patient in both SLE ($49,553 vs $26,064), and LN ($112,169 vs $39,529). Inpatient costs were approximately 3 – 5 times greater in the WMH group (Table 1).

Table 1.

Follow-up Healthcare Cost and Utilization for SLE/LN Case and Control Population

SLE with MH Comorbidities N=3,880 (WMH)SLE without MH comorbidities N=3,880 (NMH)P-valueLN with MH Comorbidities N=168 (WMH)LN without MH comorbidities N=168 (NMH)P-valueAll-cause health care utilization PPPYMeanMeanMeanMeanMean # inpatient visits1.360.50<0.00011.860.86<0.0001Mean # outpatient visits32.1121.67<0.000147.8529.45<0.0001Mean # office visits13.499.74<0.000114.9410.29<0.0001Mean # ER visits1.270.66<0.00011.400.630.0005Mean # other outpatient visits25.5517.08<0.000141.4824.19<0.0001Mean # pharmacy Rx33.3320.82<0.000136.9623.81<0.0001Length of inpatient stay (mean, days)3.691.09<0.00019.532.37<0.0001All-cause health care costs PPPYOutpatient costs (ER+ office +other)$19,271$12,847<0.0001$34,956$19,530<0.0001Pharmacy costs$7,222$4,707<0.0001$7,874$4,254<0.0001Inpatient costs$22,605$8,191<0.0001$68,216$14,680<0.0001Total costs$49,553$26,064<0.0001$112,169$39,529<0.0001

PPPY: Per patient per year; ER: Emergency room; LN: Lupus nephritis; SLE: Systemic lupus erythematosus

Conclusion:

This real-world study shows that MH comorbidities have a high incidence and prevalence rate in SLE and LN patients. Health care costs and utilization for SLE and LN patients with MH comorbidities were significantly higher than patients without MH comorbidities. This study highlights not just the high prevalence of MH comorbidity but its large contribution to SLE healthcare costs.

Figure 1.

Incidence and Prevalence Rate of Mental Health Comorbidities in the SLE and LN Populations LN: Lupus nephritis; SLE: Systemic lupus erythematosus

Disclosure of Interests:

Michelle A Petri Consultant of: Yes, Grant/research support from: Yes, Dominik Naessens Shareholder of: Yes (Johnson and Johnson), Employee of: Employee of Janssen Pharmaceuticals., Adesuwa Ogbomo: None declared, Anna Ratiu: None declared, Cynthia Gutierrez: None declared, Chetan Karyekar Shareholder of: Own Stock Options as part of being a company employee., Employee of: Current employee of Janssen Pharmaceuticals

A hotspot mutation in transcription factor IKZF3 drives B cell neoplasia via transcriptional dysregulation

Hotspot mutation of IKZF3 (IKZF3-L162R) has been identified as a putative driver of chronic lymphocytic leukemia (CLL), but its function remains unknown. Here, we demonstrate its driving role in CLL through a B cell-restricted conditional knockin mouse model. Mutant Ikzf3 alters DNA binding specificity and target selection, leading to hyperactivation of B cell receptor (BCR) signaling, overexpression of nuclear factor κB (NF-κB) target genes, and development of CLL-like disease in elderly mice with a penetrance of ~40%. Human CLL carrying either IKZF3 mutation or high IKZF3 expression was associated with overexpression of BCR/NF-κB pathway members and reduced sensitivity to BCR signaling inhibition by ibrutinib. Our results thus highlight IKZF3 oncogenic function in CLL via transcriptional dysregulation and demonstrate that this pro-survival function can be achieved by either somatic mutation or overexpression of this CLL driver. This emphasizes the need for combinatorial approaches to overcome IKZF3-mediated BCR inhibitor resistance.

High parathormone levels are associated with adverse cardiovascular events in coronary patients with high fibroblast growth factor-23

Background

Disturbances of the components of the mineral metabolism (MM) (vitamin D, phosphate, parathormone [PTH], fibroblast growth factor-23 [FGF23] and klotho) have been linked to cardiovascular disease. However, the available data are controversial, probably because most studies deal with individual rather than with the whole MM components.

Purpose

To the study the relationship between MM components and cardiovascular events, after controlling for other well-known markers (N-Terminal pro-brain natriuretic peptide [NT-proBNP], high-sensitivity troponin I [hs-TnI], and high-sensitivity c-reactive protein [hs-CRP]), and relevant clinical variables in stable coronary artery disease (CAD) patients.

Methods

We analyzed the aforementioned markers in 964 CAD patients and followed them subsequently. The primary outcome (PO) was the composite of ischemic events (acute coronary syndrome, stroke or transient ischemic attack), heart failure and death. Secondary outcomes were any ischemic event and the composite of heart failure and death.

Results

Median follow-up was 5.39 years (2.81 - 6.92). Age was 60 (52–72) years and 76.2% patients were male. Median glomerular filtration rate was 80.4 (65.3–93.1) ml/min/1.73 m2. 185 patients developed the PO.

At the univariate analysis PTH, FGF23, NT-proBNP and hs-TnI were directly associated with the PO, while calcidiol and Klotho were inversely related, and phosphate did not reach statistical significance. However, only PTH (HR 1.058 [CI 1.021–1.097]; p=0.002) and NT-proBNP (HR 1.020 [CI 1.012–1.028]; p&lt;0.001) were independent predictors of the PO at multivariate Cox regression analysis. Both PTH and NT-proBNP were also independent predictors of HF or death (HR 1.066 [1.016 - 1.119]; p=0.009 and HR 1.024 [1.014 - 1.034]; p&lt;0.001 respectively), while only PTH predicted ischemic events (HR 1.052 [1.010–1.096]; p=0.016).

After dividing patients in two subgroups according to whether they had FGF23 plasma levels above the median (85.5 RU/ml) or not, PTH remained as a predictor of the PO only in the subgroup with FGF23 &gt;85.5 RU/ml (p&lt;0.001), but not in patients with FGF23 ≤85.5 RU/ml (p=0.551). There was a significant interaction between FGF23 and PTH plasma levels (p=0.002).

Conclusion

PTH predicts cardiovascular events in CAD patients with elevated FGF23 levels even after taking into account all the other components of MM and controlling for NT-ProBNP, hs-CPR and TnI. There is an interaction between PTH and FGF23 levels, and they should be assessed together when exploring their potential predictive power.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Fondo de Investigaciones Sanitarias

Abstract PO-097: High resolution analysis of clonal dynamics using lineage tracing and single cell transcriptomics

The immense evolutionary capacity of cancer poses major challenges to current therapeutic efforts, and results from the vast clonal heterogeneity and ability of individual cancer cells to adapt to diverse selective pressures. More complete mechanistic understanding of the basis of therapeutic resistance has been limited by difficulties in coupling genetic identity of cells to their respective transcriptomic and functional outputs. To this end, we developed a novel high-complexity expressed barcode system, ClonMapper, that integrates DNA barcoding with single-cell RNA-sequencing and clonal isolation to characterize thousands of clones within a mixed cancer cellpopulation. In applying this system to breast cancer and B cell cancer cell lines in the setting of resistance to doxorubicin and fludarabine-based chemotherapy, we discover pretreatment sub-populations with distinct expression profiles that not only confer distinct treatment survivorship trajectories, but also provide the basis for long-term clonal equilibrium between co-existing clones in the absence of treatment. These data reveal the diverse clonal characteristics and therapeutic responses of a heterogeneous cancer cell population and highlight the unprecedented resolution that can be achieved using ClonMapper.

Citation Format: Eric A. Brenner, Daylin Morgan, Aziz Al'Khafaji, Catherine Gutierrez, Catherine J. Wu, Amy Brock. High resolution analysis of clonal dynamics using lineage tracing and single cell transcriptomics [abstract]. In: Proceedings of the AACR Virtual Special Conference on Tumor Heterogeneity: From Single Cells to Clinical Impact; 2020 Sep 17-18. Philadelphia (PA): AACR; Cancer Res 2020;80(21 Suppl):Abstract nr PO-097.

OP0035 EXAMINATION OF INTERSTITIAL LUNG DISEASE IN PATIENTS WITH RHEUMATOID ARTHRITIS – PREVALENCE, TIME TO ONSET, AND CLINICAL CHARACTERISTICS

Background:

Interstitial lung disease (ILD) is a known extraarticular manifestation of rheumatoid arthritis (RA). Previous studies have shown variability in the prevalence of RA-ILD, as well as clinical characteristics and risk factors of RA-ILD.

Objectives:

To evaluate the prevalence and time to onset of ILD and compare the clinical characteristics between RA patients (pts) with or without ILD using a large US electronic medical record (EMR)-based dataset.

Methods:

Pts with an initial RA diagnosis (ICD-9-CM code: 714.0; ICD-10-CM codes: M05 & M06) during the study period (01JAN2009-20SEP2019) were included from the Discus Analytics JointMan database. The initial RA diagnosis date was defined as the index date. Pts with ILD were identified by ICD diagnosis codes or by provider indication in the JointMan record. Pts who developed ILD before RA were excluded from this analysis. The prevalence and time to onset of ILD were reported. Pt demographics, comorbidities, RA characteristics and disease activity scores were compared for 6 months prior to or on the index date (baseline period) for selected adult RA pts with available information.

Results:

Among 8,963 identified RA pts, 337 (3.8%) were diagnosed with ILD on or after RA diagnosis. The median time to ILD onset post-RA was 2.3 years, and 47% had ILD within 2 years after RA diagnosis. RA-ILD pts were significantly older than those without ILD (65.8 years vs. 59.1 years; p<0.001; Table 1). At baseline, a higher percentage of RA-ILD pts had history of chronic obstructive pulmonary disease, positive rheumatoid factor, rheumatoid nodules, erosive joint disease, positive anti-cyclic citrullinated peptide antibody, and joint swelling compared to RA-only pts (Table 2). The mean ESR and RA disease activity scores were also significantly higher for RA-ILD pts.

Table 1.

Patient Demographics

Patient demographicsRA-ONLY COhort(N = 5,612)RA-ild coHORT(N = 205)P-valueAge, Mean ± SD, years59.1 ± 14.265.8 ± 11.8<.001Male, N (%)1,375 (24.5%)72 (35.1%)0.001Race, N (%) White4,014 (71.5%)165 (80.5%)0.005 African American365 (6.5%)9 (4.4%)0.226 Other/Missing1,233 (22.0%)31 (15.1%)0.020Table 2.

Baseline Clinical Characteristics

Clinical CharacteristicsRA-ONLY COhort(N = 3,846)RA-ild coHORT(N = 115)P-valueHistory of Chronic Obstructive Pulmonary Disease, N (%)102 (2.7%)8 (7.0%)0.006Hypertension, N (%)900 (23.4%)23 (20.0%)0.395Serious Infection, N (%)38 (1.0%)3 (2.6%)0.091Rheumatoid Factor Positive, N (%)1,388 (36.1%)69 (60.0%)<.001Joint Stiffness, N (%)1,092 (28.4%)39 (33.9%)0.197Rheumatoid Nodules, N (%)153 (4.0%)17 (14.8%)<.001Erosive Joint Disease, N (%)459 (11.9%)23 (20.0%)0.009Anti-CCP Antibody Positive, N (%)858 (22.3%)45 (39.1%)<.001Joint Swelling*, N (%)2,861 (58.0%)123 (68.0%)0.008Joint Tenderness*, N (%)3,728 (75.6%)138 (76.2%)0.851ESR**, Mean ± SD, mm/hr22.0 ± 22.630.1 ± 25.5<.001CRP**, Mean ± SD, mg/L22.5 ± 13.060.6 ± 25.00.086CDAI, Mean ± SD16.4 ± 12.318.9 ± 15.70.044DAS28-CRP, Mean ± SD2.6 ± 1.23.1 ± 1.4<.001DAS28-ESR, Mean ± SD3.3 ± 1.43.9 ± 1.5<.001SDAI, Mean ± SD20.2 ± 29.328.6 ± 40.20.048

* A total of 4,929 non-ILD and 181 ILD patients had joint swelling and tenderness data.

** Variables were calculated among patients who had available information.

Conclusion:

This large real-world RA population provides insight into the burden of ILD in RA pts. Pts with ILD had a higher proportion of comorbidities and RA-related conditions and higher RA activity. Further analysis is warranted to assess the risk factors of ILD and its prognosis.

Disclosure of Interests:

Joe Zhuo Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Qisu Zhang Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Keith Knapp Consultant of: In the last year, I was a paid consultant to Bristol Myers-Squibb Company., Employee of: I am a paid employee of Discus Analytics., Yuexi Wang Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Cynthia Gutierrez Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Ding He Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Lin Xie Consultant of: I am a paid employee of STATinMED Research which is a paid consultant to Bristol-Myers Squibb Company., Sonie Lama Shareholder of: I own shares of Bristol-Myers Squibb Company., Employee of: I am a paid employee of Bristol-Myers Squibb Company., Gary Craig Consultant of: I have served as a consultant to Bristol-Myers Squibb Company., Employee of: I am a paid employee of Arthritis Northwest and VP of Discus Analytics., Speakers bureau: I am a member of the speakers bureau for Bristol-Myers Squibb Company.

SAT0616-HPR IMPLICATED FACTORS IN THERAPEUTIC ADHERENCE OF PATIENTS WITH RHEUMATOID ARTHRITIS: THE PATIENT´S PERSPECTIVE

Background:

Therapeutic adherence has become a topic of growing interest for medical research. Studies have reported non-adherence rates of 20-50% in rheumatoid arthritis (RA) patients (1). Poor adherence has a negative impact on disease outcomes and implies an economic burden for the health system (2). Identifying the potential risk factors for non-adherence is essential to develop intervention strategies to solve this problem

Objectives:

To establish the contribution of illness and medication beliefs to therapeutic adherence in RA. To explore the association of treatment adherence with other patient and disease factors.

Methods:

RA patients ≥ 18 years old from a military hospital diagnosed with RA based on ACR /EULAR 2010 criteria were included in a cross-sectional study. Compliance Questionnaire Rheumatology (CQR) was used to assess treatment adherence. Unsatisfactory compliance was defined as taking correct dosing < 80%. Illness and medication beliefs were evaluated using the “Brief Illness Perception Questionnaire “(IPQ-b) and the “Beliefs about medicine questionnaire” (BMQ). Demographic data and clinical characteristics were collected by standardized clinical interview and revision of medical records.

Results:

144 patients were included the study, 106 (73.6%) women, with a mean age of 62 years (SD 12) and median disease duration of 5 years (interquartile range 25-75: 2-11). 113 (78.4%) patients showed good treatment adherence. No differences were observed regarding demographics and clinical characteristics. Strong beliefs about drugs potential damage was associated with poor compliance (13±5 vs. 11±3, p= 0.013), meanwhile increased belief in medication necessity was associated with good compliance (21±3 vs. 20±3, p= 0.015). From the illness perception measures, adherent patients had increased feeling of treatment control (8.8± 1.5 vs 7.7± 2.1,p= 0.008) and greater emotional response (6.2±3.1 vs 4.8±3.4,p= 0.042). In a multivariate analysis was found that for each unit of increase in the score of BMQ´s damage domain, adherence was reduced by 20% (CI 95% 0.7-0.9, p= 0.001); for each unit of increase in the treatment control item of the IPQ-b, adherence increased 1.42 times (CI 95% 1.1-1.8,p= 0.006); and for each unit of increase in the emotional response item of the IPQ-b, adherence increased 1.2 times (CI 95% 1.08-1.46,p= 0.002).

Conclusion:

Illness and medication beliefs could influence compliance to treatment in patients with RA.

References:

[1]van den Bemt BJ, van den Hoogen FH, Benraad B, et al. Adherence rates and association with nonadherence in patients with rheumatoid arthritis using disease modifyin antirheumatic drugs. J Rheumatol. 2009;36(10):2164–70.

[2]Martikainen JA, Kautiainen H, Rantalaiho V, et al.. Longterm Work Productivity Costs Due to Absenteeism and Permanent Work Disability in Patients with Early Rheumatoid Arthritis : A Nationwide Register Study of 7831 Patients. J Rheumatol. 2016;43(12):2101–5.

Disclosure of Interests:

María Ahijón: None declared, Patricia Carreira Grant/research support from: Actelion, Roche, MSD, Consultant of: GlaxoSmithKline, VivaCell Biotechnology, Emerald Health Pharmaceuticals, Boehringer Ingelheim, Roche, Speakers bureau: Actelion, GlaxoSmithKline, Roche, Carmen De La Cruz: None declared, Raúl Veiga: None declared, Carlos Gutierrez: None declared

Clonal dynamics in chronic lymphocytic leukemia

Chronic lymphocytic leukemia has a highly variable disease course across patients, thought to be driven by the vast inter- and intrapatient molecular heterogeneity described in several large-scale DNA-sequencing studies conducted over the past decade. Although the last 5 years have seen a dramatic shift in the therapeutic landscape for chronic lymphocytic leukemia, including the regulatory approval of several potent targeted agents (ie, idelalisib, ibrutinib, venetoclax), the vast majority of patients still inevitably experience disease recurrence or persistence. Recent genome-wide sequencing approaches have helped to identify subclonal populations within tumors that demonstrate a broad spectrum of somatic mutations, diverse levels of response to therapy, patterns of repopulation, and growth kinetics. Understanding the impact of genetic, epigenetic, and transcriptomic features on clonal growth dynamics and drug response will be an important step toward the selection and timing of therapy.

A combinatorial biomarker predicts pathologic complete response to neoadjuvant lapatinib and trastuzumab without chemotherapy in patients with HER2+ breast cancer

BACKGROUND

HER2-positive (+) breast cancers, defined by HER2 overexpression and/or amplification, are often addicted to HER2 to maintain their malignant phenotype. Yet, some HER2+ tumors do not benefit from anti-HER2 therapy. We hypothesize that HER2 amplification levels and PI3K pathway activation are key determinants of response to HER2-targeted treatments without chemotherapy.

PATIENTS AND METHODS

Baseline HER2+ tumors from patients treated with neoadjuvant lapatinib plus trastuzumab [with endocrine therapy for estrogen receptor (ER)+ tumors] in TBCRC006 (NCT00548184) were evaluated in a central laboratory for HER2 amplification by fluorescence in situ hybridization (FISH) (n = 56). HER2 copy number (CN) and FISH ratios, and PI3K pathway status, defined by PIK3CA mutations or PTEN levels by immunohistochemistry were available for 41 tumors. Results were correlated with pathologic complete response (pCR; no residual invasive tumor in breast).

RESULTS

Thirteen of the 56 patients (23%) achieved pCR. None of the 11 patients with HER2 ratio <4 and/or CN <10 achieved pCR, whereas 13/45 patients (29%) with HER2 ratio ≥4 and/or CN ≥10 attained pCR (P = 0.0513). Of the 18 patients with tumors expressing high PTEN or wild-type (WT) PIK3CA (intact PI3K pathway), 7 (39%) achieved pCR, compared with 1/23 (4%) with PI3K pathway alterations (P = 0.0133). Seven of the 16 patients (44%) with HER2 ratio ≥4 and intact PI3K pathway achieved pCR, whereas only 1/25 (4%) patients not meeting these criteria achieved pCR (P = 0.0031).

CONCLUSIONS

Our findings suggest that there is a clinical subtype in breast cancer with high HER2 amplification and intact PI3K pathway that is especially sensitive to HER2-targeted therapies without chemotherapy. A combination of HER2 FISH ratio and PI3K pathway status warrants validation to identify patients who may be treated with HER2-targeted therapy without chemotherapy.

Abstract P2-07-06: Cumulative copy number imbalances after neoadjuvant chemotherapy residual breast tumor is an independent predictor of relapse

Background: Identifying breast cancer patients after neoadjuvant chemotherapy (NAC) at greatest risk of recurrence would enhance selection of patients who may benefit from novel adjuvant treatments.

Patients. 243 stage I-III breast cancer patients who underwent NAC with ≥10% residual tumor cellularity were identified from the MD Anderson Cancer Center and Ben Taub General Hospital, Harris County hospital. Tumor DNA was isolated for DNA copy number using OncoScan CNV FFPE, Affymetrix. Median follow-up was 67.8 months. Continuous residual cancer burden (RCB) scores with CNI data were available for 152 cases. To test if CNIs covering large regions were associated with recurrence after adjusting for prognostic variables and study site, data were summed to a chromosome-arm level. Eleven chromosome arms with false discovery rate &lt;0.05 for breast cancer recurrence were identified. A stepwise multivariable model including age at diagnosis, tumor subtype, histologic grade, pre- and post-treatment stage, study site, and the 11 chromosomal arms were used to fit a parsimonious multivariate model for recurrence. Minimizing the Akaike Information Criterion yielded a final model with post-stage and a 5-arm CNI (5A-CNI) indicator including 2q, 3q, 4q, 10p, and 18p. Tumors were classified on 5A-CNI as 0 [no CNI], 1 [1- 2] and 2 [&gt; 2].

Results. The study population included 76 non-Hispanic White, 89 Hispanic, and 68 African American patients with a mean age of 49.1 years. 105 patients were classified as 5A-CNI-0, 97 as 5A-CNI-1 and 41 as 5A-CNI-2. A higher 5A-CNI score was associated with tumor grade, ER-negative tumors (p&lt;0.002) and tumor subtype (p=0.014). For 5A-CNI scores of 0, 1 and 2, recurrence rates of 14%, 34% and 58.5% were observed, respectively. In the final multivariable model adjusted for post-stage, RCB and study site, when compared to 5A-CNI-0, the hazard of recurrence was elevated for 5A-CNI-1 (HR= 2.27 [95% CI, 1.01-5.1]) and 5A-CNI-2 tumors (HR=7.43 [95% CI, 2.85-19.39]). Further, while the sample size is limiting, of 10 patients who were RCB3 and 5A-CNI-2, 9 relapsed (90%) during follow-up compared to only 6 of 43 (14%) of RCB3 patients with 5A-CNI-0 (p&lt;10-6). For patients with RCB1 or 2, relapse did not differ by 5A-CNI score. Neither race nor ethnicity were found to be independently associated with recurrence or tumor subtype. However, African American, followed by Hispanic patients, were more likely than non-Hispanic White patients to be classified as 5A-CNI-2 (p=0.013).

Table 1.Significant difference in distribution of 5 arm CNI classifier by Race/Ethnicity in Study Sample (p =0.013).5A-CNI012Non-Hispanic Whiten=44; 57.9%n=25; 32.9%n=7; 9.2%Hispanicn=32; 36%n=42; 47.2%n=15; 16.9%African Americann=28; 41.2%n=23; 33.8%n=17; 25%

Conclusion. The 5A-CNI score in post NAC tumor identifies a patient population with very poor prognosis independent of current clinical prognostic factors including RCB. Validation of these findings may lead to a post NAC genomic test that identifies patients who would benefit from additional treatment Further investigation of the nature of the association between the 5A-CNI score and race/ethnicity, which appears independent of tumor subtype, is warranted.

Citation Format: Thompson PA, Brewster A, Tsavachidis S, Armstrong G, Do K-A, Ha M-J, Gutierrez C, Symmans F, Bondy M. Cumulative copy number imbalances after neoadjuvant chemotherapy residual breast tumor is an independent predictor of relapse [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 P2-07-06.

Abstract P4-15-05: Biomarkers of response to neoadjuvant endocrine therapy with anastrozole (Ana) alone or in combination with fulvestrant (Ful) in ER-positive (ER+) HER2-negative (HER2-) breast cancer (PACT01 trial)

Background: In recent years, several clinical trials showed that fulvestrant (Ful), alone or in combination with an aromatase inhibitor (AI), is more effective than an AI alone. PACT01 is a randomized neoadjuvant trial of Anastrazole (Ana) alone or in combination with Ful in ER+/HER2- breast cancer.

Methods: Patients with newly diagnosed ER+/HER2- breast cancers, 2 cm or larger in size, were randomized to 16 weeks of Ana (1 mg orally every day) alone or in combination with Ful (500mg IM days 1, 15, 29, and every 28 days thereafter) for 16 weeks. Patients then proceeded to surgery. Tumor tissue was collected at baseline, day 28 (D28), and at the time of surgery. Primary endpoint was the reduction of Ki67 in tumor tissue between baseline and D28. Baseline and D28 samples were stained for ER, PR, HER2, and Ki67. ER and PR were scored for intensity and percentage (H-score), HER2 was scored for intensity of membrane staining; and Ki67 was scored as percentage. Data were summarized descriptively. Changes in biomarkers from baseline to D28 were calculated and compared by Wilcoxon signed rank test.

Results: PACT01 trial enrolled 72 patients. Three of them did not start treatment. Baseline samples were collected from the remaining 69 patients, and D28 samples from 60 patients (5 refused, 2 withdrew, 1 lost to follow up, 1 unknown). Samples from 18 patients had no tumor (5 at baseline, 9 at D28, 4 at both). Of the 42 patients with paired samples, 20 received Ana and 22 received Ana+Ful. All cases except one were centrally confirmed to be ER+, and all were HER2-. Table 1 summarizes median expression of Ki67, ER, and PR. Both treatment regimens led to a significant reduction in Ki67 between baseline and D28. However, Ana+Ful did not reduce Ki67 more effectively than Ana alone. Ki67 was reduced to &lt;10% in 60% of the Ana arm and 68% of the Ana+Ful, which was not statistically significant.PR was similarly reduced in both treatment arms. ER was significantly reduced at D28 in the Ana+Ful arm (p=0.0004) but not in the Ana alone arm. Safety profile of both treatment arms was consistent with package insert and published studies.

Median expression of Ki67, ER and PR in Anastrazole and Anastrazole + Fulvestrant Arms at Baseline and Day 28ARMTimepointNKi67 (%)ER H-scorePR H-scoreAnaBaseline2024.8182.5100.3 Day 28205.6*170.025.0Ana + FluBaseline2225.6198.120.5 Day 28225.1*117.50.0* p=0.0004. Other comparisons were not stastistically significant

Conclusions:In this small neoadjuvant trial, the addition of Ful to Ana did not increase Ki67 suppression at D28. This may be due to untreated primary tumors being exquisitely sensitive to Ana and that fulvestrant may not add to it. It is also possible that the effect of Ful may be noted later in the course of treatment. Further biomarker data on tissue collected at the end of treatment will be presented at the meeting.

Citation Format: Dhamne S, Nagi C, Wang T, Pavlick AC, Reusser B, Schiff R, Julie N, Niravath P, Silberfein EJ, Sedgwick EL, Sepulveda KA, Gutierrez C, Hilsenbeck SG, Chang JC, Osborne CK, Rimawi MF. Biomarkers of response to neoadjuvant endocrine therapy with anastrozole (Ana) alone or in combination with fulvestrant (Ful) in ER-positive (ER+) HER2-negative (HER2-) breast cancer (PACT01 trial) [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 P4-15-05.

Development and content validation of measures assessing adherence barriers and behaviors for use in clinical care

BACKGROUND

Providers are often unaware of poor adherence to prescribed medications for their patients with chronic diseases.

OBJECTIVE

To develop brief, computer-administered patient-reported measures in English and Spanish assessing adherence behaviors and barriers. Design, Participants, and Main Measures: Item pools were constructed from existing measures of medication adherence behaviors and barriers, which informed development of a patient concept elicitation interview guide to identify medication adherence behavior and barrier-related concepts. Two hundred six patients either living with HIV (PLWH) or without were interviewed. Interviews were coded, concepts matched to item pool content, and new items were developed for novel concepts. A provider/investigator team highlighted clinically relevant items. Cognitive interviews were conducted with patients on final candidate items (n = 37). The instruments were administered to 2081 PLWH.

KEY RESULTS

Behavioral themes from concept elicitation interviews included routines incorporating time of day, placement, visual cues, and intentionality to miss or skip doses. Barrier themes included health-related (e.g. depressed mood, feeling ill), attitudes/beliefs (e.g., need for medication), access (e.g., cost/insurance problems), and circumstantial barriers (e.g., lack of privacy, disruption of daily routine). The final instruments included 6 behavior items, and 1 barrier item with up to 23 response options. PLWH endorsed a mean (SD) of 3.5 (1.1) behaviors. The 201 PLWH who missed ≥2 doses in the previous week endorsed a mean (SD) of 3.1 (2.5) barriers. The intraclass correlation coefficient (ICC) for the numbers of behaviors endorsed in 61 PLWH after 4-16 days was 0.54 and for the number of barriers for the 20 PLWH with ≥2 missed doses the ICC was 0.89, representing fair and excellent test-retest reliability.

CONCLUSION

Measures of medication adherence behaviors and barriers were developed for use with patients living with chronic diseases focusing on clinical relevance, brevity, and content validity for use in clinical care.

[Epidemiology of Q fever in Spain (2018)]

Q fever is an anthropozoonosis whose causative agent is Coxiella burnetii, which has an important impact from the human and animal health point of view. In this review, a brief historical reference of the infection by C. burnetii and Q fever has been made initially. In a second section the basic epidemiological aspects of this infection are described (reservoirs/ sources of infection, form of transmission and epidemiological forms). Subsequently, the data of the infection by C. burnetii in Spain will be are indicated, particularly the clinical series, the seroepidemiological studies in humans, the affectation of different types of mammals and the participation of the ticks in the biological cycle. In addition, basic data on C. burnetii infection/ disease in other regions of the world will be are also included. Finally, and taking into account the previous data will indicate the main epidemiological characteristics of Q fever at present.

Lysosomal regulation of cholesterol homeostasis in tuberous sclerosis complex is mediated via NPC1 and LDL-R

Tuberous sclerosis complex (TSC) is a multisystem disease associated with hyperactive mTORC1. The impact of TSC1/2 deficiency on lysosome-mediated processes is not fully understood. We report here that inhibition of lysosomal function using chloroquine (CQ) upregulates cholesterol homeostasis genes in TSC2-deficient cells. This TSC2-dependent transcriptional signature is associated with increased accumulation and intracellular levels of both total cholesterol and cholesterol esters. Unexpectedly, engaging this CQ-induced cholesterol uptake pathway together with inhibition of de novo cholesterol synthesis allows survival of TSC2-deficient, but not TSC2-expressing cells. The underlying mechanism of TSC2-deficient cell survival is dependent on exogenous cholesterol uptake via LDL-R, and endosomal trafficking mediated by Vps34. Simultaneous inhibition of lysosomal and endosomal trafficking inhibits uptake of esterified cholesterol and cell growth in TSC2-deficient, but not TSC2-expressing cells, highlighting the TSC-dependent lysosome-mediated regulation of cholesterol homeostasis and pointing toward the translational potential of these pathways for the therapy of TSC.

Abstract P2-03-01: Analytical validation of a standardized scoring protocol for Ki67 assessed on breast excision whole sections: An international multicenter collaboration

Aims: (i) Determine whether between-observer reproducibility for Ki67 when assessed on whole sections according to a standardized scoring protocol is adequate for clinical application. (ii) Compare between-observer reproducibility of Ki67 scores assessed on hot-spots to scores using a global method that averages across a tissue section.

Background: The nuclear proliferation biomarker Ki67 has multiple potential roles in breast cancer, including aiding decisions based on prognosis, but unacceptable levels of between-laboratory variability have been observed. The International Ki67 in Breast Cancer Working Group has undertaken a systematic program to determine whether Ki67 measurement can be analytically validated and standardized across labs. In phase 1, variability in visual interpretation was identified as an important source of variability. Phases 2 and 3a showed that adherence to defined scoring methods substantially improved reproducibility in scoring tissue microarrays and core-cut biopsies. We now assess whether acceptable reproducibility can be achieved on whole sections.

Methods: Adjacent sections from 30 primary ER+ breast cancers were centrally stained for Ki67 to assemble 4 sets of 30 stained tumor sections, circulated around 23 labs in 12 countries. Ki67 was scored by 2 methods by all labs: (a) global: 4 fields of 100 tumor cells each were selected to reflect observed heterogeneity in nuclear staining (b) hot-spot: the field with highest Ki67 percentage of tumor cells with nuclear staining was selected and up to 500 cells scored. Ki67 scores were log2-transformed for statistical analyses and back-transformed for presentation. The primary objective was to assess whether either method could achieve an intraclass correlation coefficient (ICC) significantly greater than 0.8, considered substantial to almost-perfect reproducibility. Secondary objectives were to assess which method had highest observed ICC and to assess whether observers identified the same “hot-spots”.

Results: ICC for the global method was 0.87 (95%CI: 0.799-0.93), marginally meeting the prespecified success criterion. The ICC for the hot-spot method was 0.83 (95%CI: 0.74-0.90) and had a CI extending below the success criterion. Across the 23 labs, geometric mean value of the 30 scores ranged from 8.5 to 19.6 for the global method and from 12.8 to 30.3 for the hot-spot method. The overall mean (95% CI) of these values was 12.9 (11.9-14.0) and 20.9 (19.1-22.8), respectively. Visually, between-laboratory agreement in location of selected hot-spot varies between cases. The median times for scoring were 9 and 6 minutes for global and hot-spot methods respectively.

Conclusions: The global method marginally met the prespecified criterion of success; it should now be evaluated for clinical validity in appropriate cohorts of cases. The hot-spot method was observed to have slightly less reproducibility between labs. The time taken for scoring by either method is practical using counting software we are making publicly available. Establishment of external quality assessment schemes is likely to improve the reproducibility between labs further.

(Supported by a grant from the Breast Cancer Research Foundation)

Citation Format: Nielsen TO, Leung SCY, Zabaglo LA, Arun I, Badve SS, Bane AL, Bartlet JMS, Borgquist S, Chang MC, Dodson A, Ehinger A, Fineberg S, Focke CM, Gao D, Gown AM, Gutierrez C, Hugh JC, Kos Z, Lænkholm A-V, Mastropasqua MG, Moriya T, Nofech-Mozes S, Osborne CK, Penault-Llorca FM, Piper T, Sakatani T, Salgado R, Starczynski J, Sugie T, van der Vegt B, Viale G, Hayes DF, McShane LM, Dowsett M. Analytical validation of a standardized scoring protocol for Ki67 assessed on breast excision whole sections: An international multicenter collaboration [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 P2-03-01.

Identification of a divergent genotype of equine arteritis virus from South American donkeys

A novel equine arteritis virus (EAV) was isolated and sequenced from feral donkeys in Chile. Phylogenetic analysis indicates that the new virus and South African asinine strains diverged at least 100 years from equine EAV strains. The results indicate that asinine strains belonged to a different EAV genotype.

Recommendations of the Spanish brachytherapy group (GEB) of Spanish Society of Radiation Oncology (SEOR) and the Spanish Society of Medical Physics (SEFM) for high-dose rate (HDR) non melanoma skin cancer brachytherapy

Clinical indications of brachytherapy in non-melanoma skin cancers, description of applicators and dosimetry recommendations are described based on the literature review, clinical practice and experience of Spanish Group of Brachytherapy and Spanish Society of Medical Physics reported in the XIV Annual Consensus Meeting on Non Melanoma Skin Cancer Brachytherapy held in Benidorm, Alicante (Spain) on October 21st, 2016. All the recommendations for which consensus was achieved are highlighted in blue. Regular and small surfaces may be treated with Leipzig, Valencia, flap applicators or electronic brachytherapy (EBT). For irregular surfaces, customized molds or interstitial implants should be employed. The dose is prescribed at a maximum depth of 3-4 mm of the clinical target volume/planning target volume (CTV/PTV) in all cases except in flaps or molds in which 5 mm is appropriate. Interstitial brachytherapy should be used for CTV/PTV >5 mm. Different total doses and fraction sizes are used with very similar clinical and toxicity results. Hypofractionation is very useful twice or 3 times a week, being comfortable for patients and practical for Radiotherapy Departments. In interstitial brachytherapy 2 fractions twice a day are applied.

Medication understanding among patients living with multiple chronic conditions: Implications for patient-reported measures of adherence

BACKGROUND

Low health literacy is associated with poor medication adherence and poor health outcomes. Limited understanding of prescribed medications may decrease validity of patient-reported adherence measures.

OBJECTIVES

To assess knowledge of names and purposes of prescribed medications among patients with multiple chronic conditions.

METHODS

Individual interviews were conducted with a convenience sample of patients from six U.S. primary care clinics. Participants (n = 57) were English and/or Spanish-speaking patients prescribed 3+ medications for chronic conditions, for which non-adherence may lead to disability or death. In individual interviews, patients were asked to name their medications, explain the purpose of each, and to explain how they distinguish them from one another. Interviews were audio recorded, transcribed, and coded; coded content was quantified by 1) whether or not the patient could name medications; 2) method of categorizing medications; 3) whether or not the purpose of the medication was understood. Descriptive statistics were compiled using Fisher's exact test to determine the relationship between patient knowledge and medication characteristics.

RESULTS

Thirty percent of patients could not name at least one of their medications; 19% did not know their purpose; 30% held misconceptions about the purpose of one or more medications. There was no significant difference in ability to name medications or state their medication's purpose between patients using medi-sets, pre-packaged rolls, or blister packs, and patients who stored pills in their original containers (p = 0.56 and p = 0.73, respectively), or across demographic groups (p = 0.085 to 0.767).

CONCLUSIONS

Many patients demonstrated difficulty identifying the name and purpose of prescribed medications; this did not differ by demographic group or medication storage type. Patients may benefit from routine review of medications with their provider in order to improve health literacy, outcomes, and patient-reported adherence measurement.

Understanding the evolution and spread of chikungunya virus in the Americas using complete genome sequences

Local transmission of chikungunya virus (CHIKV) was first detected in the Americas in December 2013, after which it spread rapidly throughout the Caribbean islands and American mainland, causing a major chikungunya fever epidemic. Previous phylogenetic analysis of CHIKV from a limited number of countries in the Americas suggests that an Asian genotype strain was responsible, except in Brazil where both Asian and East/Central/South African (ECSA) lineage strains were detected. In this study, we sequenced thirty-three complete CHIKV genomes from viruses isolated in 2014 from fourteen Caribbean islands, the Bahamas and two mainland countries in the Americas. Phylogenetic analyses confirmed that they all belonged to the Asian genotype and clustered together with other Caribbean and mainland sequences isolated during the American outbreak, forming an 'Asian/American' lineage defined by two amino acid substitutions, E2 V368A and 6K L20M, and divided into two well-supported clades. This lineage is estimated to be evolving at a mean rate of 5 × 10^-4 substitutions per site per year (95% higher probability density, 2.9-7.9 × 10^-4) and to have arisen from an ancestor introduced to the Caribbean (most likely from Oceania) in about March 2013, 9 months prior to the first report of CHIKV in the Americas. Estimation of evolutionary rates for individual gene regions and selection analyses indicate that (in contrast to the Indian Ocean Lineage that emerged from the ECSA genotype followed by adaptive evolution and with a significantly higher substitution rate) the evolutionary dynamics of the Asian/American lineage are very similar to the rest of the Asian genotype and natural selection does not appear to have played a major role in its emergence. However, several codon sites with evidence of positive selection were identified within the non-structural regions of Asian genotype sequences outside of the Asian/American lineage.

[Atypical Guillain-Barre syndrome clustering: is it necessary to reconsider the diagnostic criteria and microbiological protocol?]

INTRODUCTION

Guillain-Barre syndrome is classically defined as a symmetrical ascending acute polyradiculoneuropathy, although there are atypical variants that make diagnosis difficult.

CASE REPORTS

The medical data of six patients in our hospital area are collected during the first quarter of 2013. Lumbar punctures, imaging, neurophysiological studies, ganglioside antibodies and serologies have been proposed in all cases. We focus on the atypical features as late hyporeflexia, increased frequency of asymmetry and distal paresis and initial fever. From a neurophysiological point of view, all patients presented sensorimotor axonal forms. The most consistent datas in early studies is the F wave's alteration. A Miller Fisher variant associated with faciocervicobraquial paresis and cerebral reversible vasoconstriction syndrome has been detected. A bilateral brachial paresis and lumbar polyradiculopathy in the context of influenza A infection is other interesting case. The saltatory variant with cranial nerve involvement and lower limbs paresis has been demonstrated in one patient. Bands in cerebrospinal fluid are positive in three cases and anti-ganglioside antibodies in one patient. The syndrome of inappropriate secretion of antidiuretic hormone may explain some of the hyponatremias registered. The first line of treatment are inmunoglobulins in all patients. Plasmapheresis exchanges has been used as an additional therapy in four cases.

CONCLUSIONS

These clusters of six axonal cases with atypical clinical features justifies the need for knowledge of these variants in order to achieve an early treatment. Late hyporeflexia and brachialfaciocervico, saltatory and lumbar forms should be considered in the spectrum of Guillain-Barre syndrome. The etiological study should rule out a lots of pathogens as influenza A.

Abstract PD2-04: FOXA1 induces a pro-metastatic secretome through ER-dependent and independent transcriptional reprogramming in endocrine-resistant breast cancer

Background: Metastasis in ER-positive (+) breast cancer (BC) occurring years to decades after initial diagnosis presents a daunting challenge for clinical care and preclinical research due to limited known key players and experimental models. FOXA1 is a pioneer factor for ER-chromatin binding and function, and is highly expressed in ER+ BC metastases, yet the underlying mechanism is unclear. Tumor-secreted proteins play a crucial role in the reciprocal interplay between cancer cells and host microenvironmental factors at both primary and secondary sites. We hypothesized that high FOXA1 provokes an ER-dependent transcriptional program that includes a unique pro-tumorigenic secretome essential for promoting ER+ BC metastasis. Methods: A lentiviral doxycycline (Dox)-inducible FOXA1 overexpression vector and a dual luciferase/GFP (LG) tracking vector were integrated to construct a stable MCF7-LG/FOXA1 cell model. Ovariectomized nude mice bearing MCF7-LG/FOXA1 xenografts in the presence of exogenous estrogen (E2) were randomized to ± Dox, each with continued E2, E2 deprivation (ED), or tamoxifen (Tam). Survival surgery removing the therapy-naïve (E2 arm) and relapsed (ED/Tam arms) tumors was performed when tumors reached ∼1000 mm3. All mice then received ED/Tam 'adjuvant' therapy, with longitudinal luminescence imaging to monitor local/distant recurrences. Mice were or will be euthanized at the ethical end-point. Integrative bioinformatics was performed using RNA-seq and FOXA1/ER ChIP-seq data from our preclinical models to identify secretome targets for functional intervention. Times to tumor regression (TTR) and progression (TTP) were defined by when the tumor reached half or twice the volume at randomization. Results: Median (m) TTR was achieved in ED (31/34 days, -/+Dox, P = 0.184) but not in Tam groups — Tam delayed tumor growth but failed to prevent progression in all mice with mTTP of 94/93 days (-/+Dox, P = 0.517). Despite no difference in mTTP at Tam-/+Dox, a quarter of +Dox tumors (3/12) had volume doubled by day 11. No metastases were observed by imaging in any of the mice before surgery ('neoadjuvant' setting). Local relapse and lymph-node/lung metastases were detected after surgery ('adjuvant' setting). At day 90 in the adjuvant Tam group with previously relapsed tumors, +Dox mice succumbed to metastasis more often than -Dox mice (7/8 vs. 3/10, P = 0.023). Compared to the adjuvant Tam+Dox mice with previous therapy-naïve tumors, the Tam+Dox with previously relapsed tumors showed higher distant metastasis rate (7/8 vs. 5/14, P = 0.026). Analysis of the ED setting is pending due to late recurrence. Data integration and functional study revealed a set of cytokines, growth factors, and extracellular matrix components (including IL-8, CTGF, and LOX), regulated by FOXA1 often in conjunction with ER, that are highly involved in FOXA1-induced metastasis. Global secretome profiling by mass spectrometry and target validation are ongoing. Conclusions: FOXA1 overexpression increases metastatic potential in ER+ BC. We established a pertinent metastatic xenograft mouse model to characterize a pro-metastatic secretome with diagnostic and therapeutic potential for treating metastatic ER+ BC.

Citation Format: Fu X, Pereira R, Zhao D, Jung SY, Jeselsohn R, Creighton CJ, Shea M, Nardone A, Angelis CD, Tsimelzon A, Wang T, Gutierrez C, Huang S, Edwards DP, Rimawi MF, Hilsenbeck SG, Brown M, Chen K, Osborne CK, Schiff R. FOXA1 induces a pro-metastatic secretome through ER-dependent and independent transcriptional reprogramming in endocrine-resistant 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 PD2-04.