11019 Background: Studies show that <10% of patients with cancer participate in clinical trials. Pragmatica – Lung (SWOG S2302) utilizes a pragmatic approach for a registrational (FDA) trial that allows less data collection and broader eligibility, thus decreasing barriers to diverse enrollment. S2302 aims to improve overall and diverse accrual by using a novel trial design and multilevel community engagement. Methods: S2302 is a real-world randomized phase III registrational study comparing pembrolizumab + ramucirumab vs investigator-chosen standard therapy in 2nd line advanced/metastatic NSCLC. A multi-stakeholder recruitment plan was developed to improve diverse accrual (with initial focus on recruiting Black patients). The plan was vetted through SWOG communications and SWOG Lung Committee’s Working Group, DEI champion, patient advocate, and community engagement subcommittee. The DEI champion identified sites in the Southeast with high minority accrual in prior trials and completed directed informational visits. An external firm created culturally and linguistically appropriate patient education material, engaged sites with historically high accrual of Black and/or LatinX patients, leveraged advocacy partners to improve community awareness, and monitored enrollment by site. A monthly accrual report with demographic summaries (including age, sex, race, ethnicity) and site enrollment information is generated from SWOG Statistics and Data Management Center to monitor accrual rate and diversity. Results: From March through December 2023 (Table), the study accrued 37% of its goal and is enrolling above its target rate of 25 pts/mo averaging 36/mo over the last 5 months. Of enrolled pts, 58% are male, 13% are Black, and 3% are LatinX; from 59 academic, 67 community (13% rural), and 2 VA sites. Comparatively, LungMAP S1800A (the phase II precursor to S2302) accrued 7% Black and 1.5% LatinX pts with an average accrual of 9.2 pts/mo. Through November, the external firm contacted 24 site PIs (63% community-based), whose sites had collectively enrolled 16 pts, for a normalized pre-call rate of 0.1340 pts/mo. After contact and through November, these sites enrolled 23 pts, a rate of 0.3835 pts/mo – a 186% increase. Conclusions: The intentional, multi-pronged recruitment plan has exceeded historical overall, Black, and LatinX patient accrual rates. The data highlight novel approaches to trial design, recruitment strategies, and increased internal and external collaboration resulting in improved diversity of clinical trial enrollment and may be a potential toolkit for future trials. Support: NIH/NCI grants U10CA180888 and U10CA180819; and in part by Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA, and Eli Lilly and Company. Clinical trial information: NCT05633602 . [Table: see text]

Abstract Disclosure: D.M. Lee: None. M. Gong: None. C. Czerlanis: None. A. Arif: None. R. Arceo-Mendoza: None. Introduction: Differentiated thyroid follicular epithelial-derived cancers include Papillary (PTC) and Follicular Thyroid Cancer (FTC). FTC is less common, accounting for only 5-15% of all thyroid cancers. It is more common in older patients and spreads via hematogenous route, with distant metastases in 10-15% of patients, commonly in the lungs and bone. We describe an unusual case of a patient with a remote history of FTC who presents with recurrence more than 50 years later in the form of a malignant pleural effusion. Clinical Case: A 79/M with a remote history of FTC that was diagnosed in the 1960s presents with one week of L sided pleuritic chest pain and dyspnea. CXR on admission showed opacification of the L hemidiaphragm. A chest CT confirmed the L sided pleural effusion. Thyroid US showed surgically absent thyroid and a 1.1cm solid nodule in the L surgical bed. PET/CT demonstrated hypermetabolic rim of L pleural effusion with no uptake in the neck. Thoracentesis was done which showed exudative pleural fluid concerning for malignancy. Immunohistochemical stains were positive for TTF-1 and thyroglobulin, consistent with metastatic thyroid cancer. He also underwent L supraclavicular lymph node FNA with findings suspicious for metastatic thyroid cancer with follicular features, with NO nuclear features of PTC. On further history, the patient reports having radiation therapy for acne around age 17 and was then diagnosed with FTC in his 20s. He underwent total thyroidectomy and RAI treatment. He recalls being told that he had a few weeks to live, and an “experimental treatment” was offered at the time, which we suspect was cobalt radiation. The patient unfortunately was eventually lost to endocrine follow up but denies any known recurrence prior to this admission. Upon discharge, an I-123 WBS was performed showing multiple foci in the R neck. Uptake is also noted in bilateral lung base, greater on the left. He was treated with 250 mCi I-131. He is currently doing well overall, asymptomatic, and with stable surveillance imaging. He is on levothyroxine suppression therapy with Tg level on a downward trend. Clinical Lesson/Conclusion: Involvement of pleural fluid by metastatic thyroid cancer though reported, is relatively rare, accounting for only less than 1% in all the patients with malignant pleural effusion. To our knowledge, there are no reported cases of malignant pleural effusions from metastatic FTC presenting remotely so many years after the initial diagnosis. The diagnosis of metastatic thyroid cancer in pleural fluid can be challenging and knowledge of the clinical context, even with remote history dating back 50 years ago just like in our case, and supporting immunohistochemical stains is essential for making the right diagnosis. Presentation Date: Saturday, June 17, 2023

PURPOSE:Sequelae of and therapies for head and neck cancers (HNC) are associated with physical and functional impairment as well as increased levels of psychological distress post treatment. Given the impact of HNC and treatment on functioning (i.e., eating and talking), health-related quality of life (HRQOL) is a significant area of survivorship concern within this population. Although prior research indicates that the incidence of anxiety and depression ranges from 15 to 50%, to date, there is a paucity of research on specific psychosocial interventions related to HNC treatment and completed studies have been limited by infrequent use of a randomized design and provision of non-standardized psychosocial interventions. This study aimed to address these gaps and utilize a brief cognitive behavioral intervention (CBI) to improve (1) self-efficacy for coping with cancer, (2) depressive symptoms, (3) other psychological symptoms, and (4) HRQOL among patients with HNC.METHODS:In an effort to conduct a randomized clinical trial of those undergoing treatment for HNC, eighty-eight patients were assigned to receive either a standardized CBI or usual psychological care (N = 47 and 41, respectively) with a 1-year follow-up. The means of all variables for both groups, adjusted for baseline, were visually compared at 3, 6, and 12 months post treatment.RESULTS:As has been a challenge in other longitudinal HNC studies, a high degree of attrition occurred, with a loss of 35 patients from the CBI group and 29 from the usual care group. Despite the high attrition, analysis of existing data indicated that the effect of CBI was discernable among the patients who completed the course of the study. Of the 38 comparisons, 34 showed that the CBI group had the favorable outcome. Important considerations for implementation of a structured psychotherapy intervention during active cancer treatment with multiple barriers including communication challenges and practical limitations were realized.CONCLUSIONS:The impact of HNC treatment can be particularly distressing as it often results in functional impairment and markedly changed activities of daily living among survivors. However, engaging in therapeutic methods to cope and manage distress during treatment can influence QOL and mood into the survivorship phase.

BACKGROUND In December 2013 the US Preventative Services Task Force (USPSTF) recommended annual lung cancer screening for high-risk patients. The Centers for Medicare & Medicaid Services (CMS) later announced coverage in 2015. The impact of these federal decisions at the population level is unknown.METHODS Using the Surveillance, Epidemiology, and End Results database, we studied changes in lung cancer incidence by stage and linked to US census data to obtain age-adjusted estimates standardized to the US popu-lation. Based on age at diagnosis we stratified patients as age-eligible or age-ineligible for screening. We used difference-in-differences regression to determine the effect of screening on lung cancer incidence by stage.RESULTS For all age groups the incidence of early-stage lung cancer both before and after the USPSTF guidelines remained relatively stable at 12.8 +/- 0.52 and 13.5 +/- 0.92 per 100,000 patients, respectively (P = .068). However the difference-in-differences analysis estimated an absolute increase in the age-adjusted incidence by 3.4 per 100,000 persons in the age-eligible group after the announcement of the guidelines (P = .007). The effect was even larger after the CMS decision (4.3/100,000 persons, P < .001). Similarly there was a 14.2 per 100,000 persons absolute reduction in the incidence of advanced-stage lung cancer (P < .001).CONCLUSIONS The 2013 USPSTF lung cancer screening guidelines and CMS coverage decisions were associated with an increased incidence of early-stage lung cancer and decreased incidence of advance-staged lung cancer at the population level.(Ann Thorac Surg 2023;115:827-34)Published by Elsevier Inc. on behalf of The Society of Thoracic Surgeons

The number of patients diagnosed with endometrial cancer surpasses that of any other gynaecological cancer. This disease is usually detected early after disease onset and with current therapy 80 percent of patients with early-stage disease reach a five-year survival milestone. However, patients with advanced or recurrent disease have a grim outcome and the five-year survival rate for these patients is only about 16 percent. In several cancer types there is accumulating evidence that immune cells play a crucial role in the initiation, progression and outcome of disease. In order to provide novel and effective immunotherapeutic treatments for advanced disease endometrial cancer, an understanding of the relevance of immune cells needs to be addressed. This review briefly discusses current knowledge in the area of immune cells and how they may alter the course of endometrial cancer, as well as the implications of these cells for novel therapy and outcome.

BACKGROUND:Hematology and oncology patients represent a complex population that requires timely follow-up to prevent clinical decompensation and delays in treatment. Previous reports have demonstrated that follow-up within 14 days is associated with decreased 30-day readmissions, and the magnitude of this effect is greater for higher-risk patients. This project was designed to standardize the discharge process with the primary goal of reducing average time to hematology and oncology follow-up to < 14 days.METHODS:Using Plan-Do-Study-Act (PDSA) quality improvement methodology, a multidisciplinary team of hematology and oncology staff developed and implemented a standardized discharge process. Rotating resident physicians were trained through online and in-person education. Additional interventions included the development of a discharge checklist handout, and a clinical decision support tool including a note template and embedded order set. All patients discharged during the 2-month period before and after the implementation of the standardized process were evaluated. Follow-up appointment scheduling data and communication between inpatient and outpatient providers were reviewed.RESULTS:A total of 142 consecutive patients were reviewed. The primary endpoint of time to hematology and oncology follow-up appointment improved from a mean 17 days prior to intervention to 13 days in PDSA cycles 1 and 2 and 10 days in PDSA cycle 3. The target of 14-day average time to follow-up was achieved. Furthermore, the upper control limit decreased from 58 days at baseline to 21 days in PDSA cycle 3, demonstrating a decrease in variation. Electronic alerting of outpatient hematology and oncology providers to discharge summary increased from 20% before the intervention to 62% after the intervention (P = .01).CONCLUSIONS:This quality initiative to standardize the discharge process for the hematology and oncology service decreased time to hematology and oncology follow-up appointments, improved communication between inpatient and outpatient teams, and decreased process variation. Timelier follow-up for this complex patient population will prevent clinical decompensation and delays in treatment.

•Describe patient data collected at weekly “Lightning Rounds” for medical trainees on Heme/Onc service at VA hospital.•Assess six-month survival rate for patients rounded on during “Lightning Rounds.” A growing body of evidence suggests that improving physician prognostication in patients with advanced cancer may allow for improved end of life care. Although the data suggests oncologists struggle with accurately predicting patients' prognosis, there is a dearth of literature on medical residents' abilities to prognosticate. This project aims to assess the six-month survival rate for oncology inpatients at our institution, as well as how accurately medical residents identify six-month prognosis. The Palliative Care Consult Team (PCCT) conducted weekly “Lightning Rounds” (LR) with medical residents on the inpatient heme/onc service. Residents answered questions about each inpatient regarding goals of care and prognosis (the “surprise question”). Patient survival at six months was assessed via review of the electronic medical record (EMR). Over 12 months, the PCCT rounded on 65 unique patients on the heme/onc service. In the six months following LR, 46% of patients died (average days of life following LR = 138). Of the patients who were rounded on and died, residents predicted this accurately 66% of the time—i.e., doctors said, “I would NOT be surprised if this patient died in the next six months.” In addition, doctors predicted with slightly higher accuracy—68.5%—the patients who would live beyond six months. Our initial results suggest that the medical residents demonstrated greater accuracy with prognostication at six months than has been shown in previous studies. Potential explanations for this result include: increased sensitivity to the six-month surprise question (SQ), weekly practice of prognostication, and use of prognostic tools taught during LR didactics.

To prospectively assess the quality of life (QOL) in patients with clinically diagnosed early-stage lung cancer undergoing definitive stereotactic body radiation therapy (SBRT). We enrolled medically inoperable, clinically diagnosed T1-3N0M0 lung cancer patients without a confirmed pathologic diagnosis. Reasons for lack of pathologic confirmation included high risk of biopsy-related complications, prior non-diagnostic biopsy, or patient refusal. Patients were diagnosed based on ≥85% risk of malignancy using Herder et al PET-based prediction model estimate or consensus recommendation from thoracic multidisciplinary tumor board. QOL was scored using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 (QLQ-C30) and Lung Cancer-13 questionnaires (QLQ-LC13). QOL scores were measured at baseline, 3 months, 6 months, 1 year, and 2 years. A clinically meaningful change in QOL was defined as an increase or decrease in 10 points relative to the baseline, which has been previously validated to correspond to 'moderate' or 'very much' change by Osaba et al, 1998. Patients who developed disease progression were excluded from the QOL analysis after disease progression for risk of competing decline in QOL. Linear mixed-effects model was utilized to evaluate change in QOL scores over time. From 2016-2019, 43 patients were enrolled. Median follow-up is 11.0 months (IQR 6.0-26.1). Mean age was 74.2 years ± 8.3. Mean Charlson Comorbidity Index was 5.5 ±1.8. Compliance rate with QOL was 84.3%. QLQ-C30 scores for global health, functioning scales, and select QLQ-C30 and QLQ-LC13 symptom scores are shown in the Table. There was no significant change in global health/QOL at any time. Regarding the functional scales, there was improvement in social functioning at 1 and 2 years compared to baseline but without statistical significance. There were no significant differences in any of the functional scales at any time point. There was transient worsening in cough at 1 year, which returned to baseline at 2 years. There were no significant differences in any of the symptom scales at any time point otherwise. In medically inoperable patients with clinically diagnosed early stage lung cancer treated with SBRT, QOL was preserved without significant decline in global health, functional domains, or symptoms in this first planned analysis early in follow up. Longer follow up will be required to confirm these results.Abstract 2489; TableQOL scores.Baseline3 month6 month1 year2 yearp-valueGlobal Health63 ± 2265 ± 2257 ± 2967 ± 1657 ± 260.31Physical functioning62 ± 2464 ± 2559 ± 2761 ± 2059 ± 220.76Role functioning64 ± 3172 ± 3167 ± 3572 ± 3269 ± 330.87Emotional functioning72 ± 2175 ± 2376 ± 2778 ± 2873 ± 250.68Cognitive functioning81 ± 2373 ± 2978 ± 2581 ± 2676 ± 250.12Social functioning71 ± 3480 ± 2776 ± 2883 ± 2585 ± 180.70Fatigue36 ± 2238 ± 2639 ± 2733 ± 2432 ± 190.93Coughing36 ± 2933 ± 2436 ± 2949 ± 3141 ± 220.35Dyspnea34 ± 2635 ± 2537 ± 2933 ± 2337 ± 240.92 Open table in a new tab

This review provides an update on the current use of immune checkpoint inhibitors (ICI) in female gynecologic cancers, and it addresses the potential of these agents to provide therapy options for disease management and long-term remission in advanced disease patients, where surgery, chemotherapy, and/or radiation fail to meet this goal. The topic of immune checkpoint inhibitors (ICI) blocking cytotoxic T lymphocyte associated protein-4 (CTLA-4) and the programmed death-1 (PD-1) axis has come to the forefront of translational medicine over the last decade for several malignancies. The text will focus primarily on a discussion of ovarian cancer, which is the most frequent cause of death of gynecologic cancers; endometrial cancer, which is the most often diagnosed gynecologic cancer; and cervical cancer, which is the third most common female gynecologic malignancy, all of which unfavorably alter the lives of many women. We will address the critical factors that regulate the outcome of these cancer types to ICI therapy, the ongoing clinical trials in this area, as well as the adverse immune responses that impact the outcome of patients given ICI regimens.

Patients with intravascular large B-cell lymphoma often pose a significant diagnostic challenge, particularly in the early stages of the disease, but use of fluorodeoxyglucose-positron emission tomography could result in a more timely diagnosis.

Treatment of reverse pseudohyperkalemia for a patient with chronic lymphocytic leukemia was complicated by falsely reported elevated potassium levels.

Cancer care delivery is highly complex. Treatment involves coordination within oncology health-care teams and across other teams of referring primary and specialty providers (a team of teams). Each team interfaces with patients and caregivers to offer component parts of comprehensive care. Because patients frequently obtain specialty care from divergent health-care systems resulting in cross-system health-care use, oncology teams need mechanisms to coordinate and collaborate within and across health-care systems to optimize clinical outcomes for all cancer patients. Transactive memory is one potential strategy that can help improve comprehensive patient care delivery. Transactive memory is a process by which two or more team professionals develop a shared system for encoding, storing, and retrieving information. Each professional is responsible for retaining only part of the total information. Applying this concept to a team of teams results in system benefits wherein all teams share an understanding of specialized knowledge held by each component team. The patient's role as the unifying member of the team of teams is central to successful treatment delivery. This clinical case presents a patient who is receiving oral treatment for advanced prostate cancer within two health systems. The case emphasizes the potential for error when multiple teams function without a point team (the team coordinating efforts of all other primary and specialty teams) and when the specialty knowledge of providers and patients is not well integrated into all phases of the care delivery process.

e14033 Background: Ovarian cancer (OvCa) is usually diagnosed at an advanced stage and relapse is common despite current treatments. The number of circulating CD4+ T regulatory cells (Tregs) correlates inversely with outcome in advanced OvCa. Novel immunotherapy is needed to stimulate anti-tumor host immune responses. Patients were treated with a mature dendritic cell (DC) vaccine (α-DC-1), to determine if this strategy reduces circulating Tregs and augments IFN-γ immune responses. Methods: Patients with relapsed/refractory or suboptimally debulked ovarian or primary peritoneal carcinoma were eligible. IL-12p70 secretion is an indicator of DC potency and primer of tumor-specific cytotoxic T cell responses. Vaccines consisted of 1-28 x 106 mature α-DC-1 cells, loaded with autologous tumor lysate and KLH (195-3195 pg/ml IL-12p70), harvested day 7. The cells were injected intranodally every other week for 3 doses per cycle, up to 3 cycles. CD4+CD25highFoxP3+CD127low Tregs were monitored weekly by monoclonal antibody labeling of PBMC and flow cytometry. Levels of IFN-γ secreted by PBMC were studied with ELISpot at leukapheresis and 2 points after cycle 1. Standard methods were used to assess disease. Results: Eight women, 6 of whom had minimal residual disease, received ≥ 1 cycle (median 2.3). No grade 3-4 toxicities were seen. Median progression free survival was 5.6 months (range 2.2-15.0), and median overall survival has not been reached. PBMC from all subjects were positive for IFN-γ secretion on 48-hr stimulation with positive control PMA/ionomycin and with KLH, and 2/8 (25%) on tumor lysate challenge. PBMC analysis at baseline and 2 or 3 weeks post cycle 1 showed that 4 of 7 evaluable patients (57%) had ≥ 20% Treg reduction. Mean Tregs/CD3+ T cells for controls were .92% (range .69-1.29). Mean Tregs/CD3+ T cells for vaccine subjects were 1.68% (range 1.22-2.13) at baseline. For 6 patients who received ≥ 2 vaccine cycles, mean Tregs/CD3+ T cells were 1.55% (range 1.13-2.08) after cycle 2, and 1.36% (n = 3) after cycle 3 (range .81-2.26). Conclusions: Administration of mature α-DC-1 vaccine resulted in anti-tumor IFN-γ immunity to tumor lysate antigens in 25% of subjects. Overall there was a modest reduction in CD4+ Tregs with DC vaccine therapy. Clinical trial information: NCT00703105.

Abstract Background: Resistance to endocrine therapy (ET; tamoxifen or aromatase inhibitors, AI) for ER+ breast cancer is a major cause of mortality and new treatment paradigms are needed. Cancer stem cells drive breast cancer growth and are resistant to standard therapy. Notch signaling aids survival of these resistant stem cells and is inhibited by gamma-secretase inhibitors (GSI). We showed combining GSI with ET in mice caused shrinkage of breast cancer tumors. A presurgical window biomarker modulation model was used to confirm this discovery in humans. Methods: The GSI MK-0752 was added to ET in patients before definitive surgery (ClinTrials.gov NCT00756717). There were 3 biopsies: day 0 (prestudy), day 14 (after ET alone), and day 25 at definitive surgery (after continued ET plus MK-0752, 350 mg orally 3d on, 4d off, 3d on). Biopsies were analyzed for genes increased or decreased by GSI, to confirm that Notch and cancer stem cell pathways were inhibited. Real-time PCR was used to validate expression of genes identified in pathway analyses of microarray datasets generated from the biopsies. Mammosphere-forming assays were performed to confirm that ET+GSI impacts breast cancer stem cells. The qRT-PCR data were evaluated using ANOVA with repeated measures and ANOVA was performed on mammosphere results. Results: The accrual goal was met and therapy well-tolerated in 20 evaluable women (PSABCS 2011, abs# S1-5). Of 33 genes identified by analysis of expression microarrays, 19 genes (FDR<8%) were impacted significantly by GSI+ ET (3 increased, 16 decreased) compared to initial biopsy and/or ET alone. Genes with increased expression were DAXX, NOXA (both pro-apoptotic) and LNFG (tumor suppressor). Six of 16 genes that decreased (NOTCH1, NOTCH4, HEYL, HES1, HES5, and HEY2) are Notch pathway-associated genes. The GSI decreased expression of 3 genes from cell cycle and proliferative pathways (Ki67, CCND1, CCNA2) and inhibited 2 genes expressed in cancer stem cells (RUNX1 and ALDH1A1). Five genes directly/indirectly regulated by Notch were decreased by GSI (RICTOR, RPTOR, MMP7, ADAM19, and PRH). Estrogen deprivation for 3 days, mimicking short exposure to an AI, increased mammosphere-forming ability of ER+ breast cancer cells more than 2 fold. The GSI MRK-003 blocked this mammosphere formation by 95%-98%. Conclusions: A 7-day course of the GSI MK-0752 added to ET in the presurgical window had significant biomarker responses: decrease in Notch signaling, cancer stem cell genes, proliferation-associated genes, the mTORC1 and 2 complex genes RICTOR and RPTOR, metalloproteinases that promote metastasis, and PRH; as well as increase in 3 key genes that promote apoptosis and tumor suppression. These results suggest that 1) GSI inhibited the intended Notch pathway, 2) putative breast cancer stems cells can be targeted by this strategy, and 3) the biomarkers identified create a gene signature for anti-Notch therapy in ER+ breast cancer. Validation of efficacy of the GSI+ET therapy combination and this gene signature in a clinical trial is planned. Support: Breast Cancer Research Foundation (research grant), Merck Oncology (drug/arrays), Swim Across America (clinical trial costs), and DOD BC073237 (KRC). Citation Format: Kathy S Albain, Andrei Y Zlobin, Kyle R Covington, Brian T Gallahger, Susan G Hilsenbeck, Cheryl M Czerlanis, Shelly Lo, Patricia A Robinson, Ellen R Gaynor, Constantine Godellas, Davide Bova, Kathy Czaplicki, Barbara Busby, Patrick J Stiff, Suzanne AW Fuqua, Lucio Miele, Clodia Osipo. Identification of a notch-driven breast cancer stem cell gene signature for anti-notch therapy in an ER+ presurgical window model [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr S4-03.

Ovarian cancer is one of the most frequent gynecological malignancies. However, as there is no effective screening method to detect early disease, it is usually only diagnosed when already widespread in the abdomen. The majority of patients diagnosed with advanced-stage disease will relapse and require additional therapy. In the search for additional effective treatments for the management of recurrent disease, researchers have focused on the potential usefulness of immunotherapeutic modulation by administering autologous immune cells, such as dendritic cells (DCs), to stimulate antitumor host responses. With the ultimate goal of improved survival, this review addresses mechanisms in ovarian cancer that may limit the expansion of antitumor immunity, discusses the parameters to be considered for optimal DC immunotherapy, outlines evaluation methodology used to monitor the success of treatment regimens and reviews reported DC immunotherapy trials in ovarian cancer.

e13121 Background: The number of circulating CD4+ regulatory T-cells (Tregs) has been correlated with outcome in advanced ovarian cancer. A prior report (Barnett, et al; AACR Abstracts 2006: 1148) suggested that denileukin diftitox, a fusion toxin containing interleukin-2 fused to diphtheria toxin, may be of therapeutic value in this disease acting via Treg depletion. As part of a larger study of denileukin diftitox with dendritic cell-based vaccination, we treated patients with the agent alone to determine if it depletes circulating CD4+CD25HiFoxP3+CD127Low Tregs and induces clinical responses. Methods: Patients with relapsed/refractory ovarian or primary peritoneal carcinoma were eligible. No chemotherapy or immunotherapy was allowed for the preceding 4 weeks. Denileukin diftitox 18 μg/kg IV was given every 28 days for up to 4 cycles. Weekly monitoring of CD4 Tregs and CD8+CD28- Tregs was done by monoclonal antibody labeling of PBMC and flow cytometry studies. Clinical responses were measured by standard methods of disease assessment including CA125 testing. Results: Seven women were treated, of whom 3 had minimal residual disease (MRD). No Grade III-IV toxicities were seen. Unlike the prior report, no clinical responses were seen in 4 patients with bulky measurable disease. Median progression free survival was 5.5 months (range 0.5-20.5) and median overall survival will exceed 21.6 months (range 1.4-26.5+) with MRD a marker for prolonged remissions and survival. We saw no Treg depletion after the 1st cycle; i.e., no patient had ≥25% reduction in Tregs at the expected nadir at day 14. Mean CD4+CD25HiFoxP3+CD127Low Tregs/CD4 cells for controls was 1.16% (range .35-2.13) at baseline, with no significant temporal variation. Mean Tregs/CD4 cells for treated subjects was 2.89% (range 1.06-5.40) at baseline and 3.11% (range .81-5.13) at day 14. For 6 patients who received ≥2 cycles, mean Tregs/CD4 cells dropped to 1.95% (range .71-3.74) at day 42 and 1.65% (range .78-2.36) at day 70. CD8+CD28- Tregs were only increased (>50% of CD8 T-cells) in 2 patients and not correlated with remission duration. Conclusions: These data suggest that denileukin diftitox depletes Tregs in relapsed ovarian cancer only with repeated dosing and may be of clinical value in MRD.

Abstract Background: New strategies to enhance endocrine therapy (ET) efficacy and/or overcome resistance by targeting key survival pathways are needed. Preclinical data indicate that unwanted effects of ET include reactivation of the Notch pathway, critical for breast tumor initiating (stem) cells. Notch inhibition with gamma secretase inhibitors (GSI) enhances tamoxifen (tam) efficacy in xenografts, but impact of GSI+ET in human breast cancer (BC) is unknown. Our objective was to add short exposure of the GSI MK-0752 to ongoing tam or letrozole (let) in the presurgical window to assess feasibility, safety and biomarker/pathway impact in a 20-patient (pt) pilot study (ClinTrials.gov NCT00756717). We previously evaluated several biomarkers in the first cohort, which showed promise with Notch and proliferation inhibition. We present new results adding the final cohort, plus additional biomarkers and microarray analyses. Methods: Pts with early stage ER+ BC received 25 days (d) of ET. MK-0752 was added d15 (350 mg PO 3d on, 4d off, 3d on) with definitive surgery d25. Core biopsies were done at baseline, d14 and d25, with qRT-PCR for Notch-related and other genes critical to stem cell renewal/proliferation. Gene expression levels after GSI (d25) vs ET alone (d14) were analyzed and d25 changes in all pts combined for each gene were compared. Microarray expression estimates and modeling were performed using dCHip and Red-R, implementing gene-wise comparisons using Limma. Probes were defined as significantly regulated by paired t tests if p ≤ 0.001 for the comparisons of baseline to tam/let and tam/let to tam/let+GSI. Data were exploratory so all probe data were included in the modeling, and no corrections for multiple comparisons were used. Differentially expressed genes were submitted to DAVID for pathway analysis. Results: Of 22 pts accrued, 20 (11 tam, 9 let) were evaluable, meeting accrual goals (2 withdrew before MK-0752); 19 completed therapy to date. Toxicity was minimal. Significant (p<.05) changes in mRNA levels after GSI+ET vs end of ET in 17 pts (3 in progress) were down-regulation of Notch4 in 13; Ki67, 13; Notch1, 12; RUNX1 (stem cell transcription factor), 13; ADAM19 (disintegrin/metalloproteinase), 12; MMP7 (Wnt target), 11; CCND1 (cyclin D1), 10; and up-regulation of NOXA (pro-apoptotic BH3-only gene), 13. Microarray analyses (10 completed, remainder underway) found significant numbers of GSI-regulated genes that were independent of tam/let. Of 4036 genes increased by GSI, 2777 were unchanged by tam/let; of 3978 genes decreased by GSI, 1017 were not impacted by tam/let. For example, of genes regulated by GSI alone, there was modulation of important cancer pathways: Wnt5a, FGFs, FGFR, IGF-1R were decreased; Fas and caspases were increased. These changes in gene expression are being compared with ET resistance profiles. Conclusions: Short exposure of MK-0752 added to ET was feasible, well tolerated, and resulted in significant biomarker response in all tumors. MK-0752 favorably modulated proliferation, apoptosis, stem cell and metastasis-related targets, and impacted critical cancer pathways. This suggests potential roles for MK-0752 in optimizing endocrine therapy and overcoming endocrine resistance. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr S1-5.

Abstract Background: Breast tumor initiating cells (TIC) use Notch receptors/ligands with other pathways for self renewal, resulting in tumor proliferation and progression. We showed that Notch inhibition with gamma secretase inhibitors (GSI) potentiates the effects of tamoxifen (tam) in xenografts (Rizzo et al. Cancer Res 2008). It is unknown whether GSIs plus endocrine therapy result in modulation of Notch and other proliferation markers in human breast cancer. Our objective was to add short exposure of the GSI MK-0752 to ongoing tam or letrozole (letr) during the presurgical window to determine 1) feasibility, 2) safety/tolerance, and 3) impact on biomarkers. We report the initial cohort of this pilot study (ClinTrials. gov NCT00756717). Methods: Patients (pts) with early stage ERα + breast cancer were treated with 25 days of tam or letr. On day 15 MK-0752 was added to endocrine therapy (350 mg orally 3 days on, 4 days off, 3 days on), with definitive surgery day 25. Formalin fixed, paraffin embedded biopsies were obtained at baseline, day 14 and final surgery, with histologic confirmation of tumor content >50% and RNA extraction by standard methods. Q-PCR was done for Notch1, Notch3, Notch4, Deltex, Jagged1, c-myc, HEY1, HEY2, HES1, PS2, C-Myc, Cyclin A2, NOXA (pro-apoptotic protein), Ki67, Dicer-1, RPL13 (internal control). Ct averages for 3 replicates were used and mRNA levels were calculated by the 2ΔΔCt method. Baseline gene expression levels were used as comparators for days 14 and 25 levels in each pt. The first cohort of 10 pts was analyzed to determine if enough signals were present to justify expanding the cohort at this dose to 20 pts and possibly test a second cohort on an alternate MK-0752 dose/schedule. Results: The initial cohort of 10 pts completed all therapy (4 tam, 6 letr), all biopsies and definitive surgery on schedule. One other pt withdrew prior to starting MK-0752 due to hypertension. Toxicity was minimal: grade 1 periorbital edema/cough, nausea, and axillary paresthesias in 1 pt each; grade 1 facial rash, 2 pts; and grade 2 fatigue, 1 pt. There was no diarrhea or surgical complications. Significant changes occurred in molecular marker levels after MK-0752 plus tam/letr (day 25) vs. end of tam/letr alone (day 14) as follows: Ki67 mRNA decreased in 9/10 pts; Notch4 decreased, 10/10; NOXA increased, 6/10; and Notch1 decreased, 6/10. Other markers showed inter-individual variations and will be presented, along with results of the global gene expression profiling (in progress). Conclusions: The addition of a short exposure of the GSI MK-0752 to ongoing endocrine therapy was feasible, safe, and well tolerated in pts with ERα + early breast cancer prior to definitive surgery. It results in anti-proliferative and pro-apoptotic effects at the molecular level. Notch4, which plays a key role in breast TIC, was the most consistent molecular marker of response in this setting. This suggests a potential anti-TIC effect of this combination and a role in overcoming endocrine resistance. Accrual to the expanded cohort is underway. If findings are confirmed, the second study with alternate MK-0752 dose/schedule may commence. Funding: Swim Across America, Inc. (clinical trial costs); Merck (drug supply, profiling) Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr PD05-12.