Kaye, Frederic J.

e24125 Background: Gynecologic, gastrointestinal (GI), and thoracic cancers account for significant morbidity and mortality in the U.S. Women with these types of cancers frequently experience psychological distress, among other poor outcomes. Previous research has indicated that mindfulness-based interventions, such as yoga, can be effective in decreasing distress in cancer patients. Notably, this research has primarily been conducted in a breast cancer population with limited research assessing the feasibility, acceptability, and/or efficacy of this type of intervention in other prevalent and impactful cancers among women. The purpose of the present study was to assess the Feasibility and Acceptability of a yoga intervention for women with gynecologic, GI, or thoracic cancers. Methods: A total of 124 women diagnosed with a gynecologic, GI, or thoracic cancer in the prior year were recruited via outpatient oncology clinics to participate in a 10-week, group-based manualized yoga intervention entitled “Stilling the Waters of Uncertainty” (Author: E. Kacel) that is nearing the end of accrual. Participants completed an Acceptability evaluation following each yoga session with ratings on a 5-point Likert scale from “not at all” to “extremely.” Feasibility of the study was operationalized as percentage of eligible participants who (a) enrolled, (b) attended sessions, and (c) completed post-intervention assessment. Acceptability was operationalized as the percentage of participants with average session ratings of “very” or “extremely” for intervention usefulness, enjoyableness, safety, clarity, relevance, and likelihood of continuing to practice skills. Criteria for operationalizing Feasibility and Acceptability for this study were defined a priori based on recommendations of Bowen and colleagues (2009). A minimum of 80% for each measure of feasibility and acceptability was set as the a priori threshold of success in each domain. Results: All measures of Feasibility were below the a priori benchmark of 80%: Of the 318 eligible patients approached for participation, (a) 124 patients (39.0%) enrolled; 49/124 (39.5%) attended at least 1 yoga session; 44/124 (35.4%) attended at least 8 sessions; and (c) 41/124 (33.1%) completed post-intervention assessment procedures. At least 80% of attendees rated the intervention as “very” or “extremely” useful, enjoyable, safe, and clear; 75.5% and 79.6% of attendees rated the intervention as “very” or “extremely” relevant and likely to be continued to be practiced. Conclusions: The results of this study indicate that a yoga intervention for women with prevalent non-breast cancer types did not meet a priori criteria for feasibility. However, participants who attended at least 1 session rated the intervention as generally acceptable. Future research is needed to improve study/intervention feasibility in this population. Clinical trial information: NCT03385577.

12129 Background: Depression, anxiety, and fear of cancer recurrence (FCR) constitute prevalent psychological concerns necessitating further attention in developing supportive care interventions for women with gynecologic, gastrointestinal, and thoracic cancers. Recent evidence indicates that such concerns may be especially severe among underserved women of color and women affected by low-socioeconomic status (SES). The purpose of the present study is to evaluate the magnitude of changes in depression, anxiety, and FCR associated with a mindfulness-based yoga intervention among a diverse sample of women with these cancers. A second aim is to identify how changes in these concerns may differ across sociodemographic groups. Methods: Women with gynecologic ( n=86), gastrointestinal ( n=17), or thoracic ( n=20) cancers were enrolled in a group-based 10-week yoga intervention utilizing mindfulness meditation, relaxation, and gentle yoga. Prior to and following intervention, participants were administered assessments, including the Beck Depression Inventory – Second Edition (BDI-II) to measure depression, the State-Trait Anxiety Inventory (STAI) to assess anxiety, and the Fear of Cancer Recurrence Inventory (FCRI) to evaluate aspects of FCR. Mixed-linear models evaluated change in outcomes from pre- to post-intervention, with conditional models assessing the effects of age, race/ethnicity, and SES on change. Analyses were conducted prior to trial completion due to approaching accrual period termination. Results: The sample demonstrated a mean age of 58.46 ( SD=10.82) and mean SES score of 3.98 ( SD=1.55) using a 1 to 7 composite scale. Twenty-six percent of participants were of racial and/or ethnic minority status ( n=32). Significant declines in total depressive symptoms, somatic depressive symptoms, state anxiety, and psychological distress due to FCR were observed across the sample. Higher SES was associated with significantly greater reductions in total depressive symptoms and affective depressive symptoms, specifically. Women of color experienced significantly greater declines in somatic symptoms compared to non-Hispanic White women. Conclusions: This mindfulness-based yoga intervention was associated with significant reductions in depressive symptoms, state anxiety, and psychological distress related to FCR among women with gynecologic, gastrointestinal, and thoracic cancers. Higher SES and underserved race/ethnicity status moderated some of these effects. Future research should explore the efficacy of this intervention among diverse women in a randomized clinical trial context. Clinical trial information: NCT03385577.

No effective systemic treatment is available for patients with unresectable, recurrent, or metastatic mucoepidermoid carcinoma (MEC), the most common salivary gland malignancy. MEC is frequently associated with a t(11;19)(q14-21;p12-13) translocation that creates a CRTC1-MAML2 fusion gene. The CRTC1-MAML2 fusion exhibited transforming activity in vitro; however, whether it serves as an oncogenic driver for MEC establishment and maintenance in vivo remains unknown. Here, we show that doxycycline-induced CRTC1-MAML2 knockdown blocked the growth of established MEC xenografts, validating CRTC1-MAML2 as a therapeutic target. We further generated a conditional transgenic mouse model and observed that Cre-induced CRTC1-MAML2 expression caused 100% penetrant formation of salivary gland tumors resembling histological and molecular characteristics of human MEC. Molecular analysis of MEC tumors revealed altered p16-CDK4/6-RB pathway activity as a potential cooperating event in promoting CRTC1-MAML2–induced tumorigenesis. Cotargeting of aberrant p16-CDK4/6-RB signaling and CRTC1-MAML2 fusion–activated AREG/EGFR signaling with the respective CDK4/6 inhibitor Palbociclib and EGFR inhibitor Erlotinib produced enhanced antitumor responses in vitro and in vivo. Collectively, this study provides direct evidence for CRTC1-MAML2 as a key driver for MEC development and maintenance and identifies a potentially novel combination therapy with FDA-approved EGFR and CDK4/6 inhibitors as a potential viable strategy for patients with MEC.

Abstract Purpose Delta-like protein 3 (DLL3) is being developed as a predictive biomarker for DLL3-targeting antibody-drug conjugate and other therapies. Given the neuroendocrine features of Merkel cell carcinoma (MCC), we sought to evaluate DLL3 expression and its role in MCC. Experimental Design Formalin-fixed and paraffin-embedded MCC cases were consecutively selected. Immunohistochemistry was performed for DLL3 (SC16.65 antibody) and polyomavirus large T-antigen (sc-136172 antibody). Slides were read out for percentage of positive tumor cells. Cox proportional hazards model was applied to assess the association between DLL3 expression and overall survival (OS). A patient with a DLL3-expressing MCC was treated with rovalpituzumab tesirine (Rova-T) in the “other tumor” cohort of NCT02709889 and assessed for response. Results The median H-score of DLL3 expression of 65 patients included was 60 (interquartile range, 30–100). Fifty-eight cases (89%) had ≥1% tumor cells positive for DLL3 expression with any intensity, of which the median DLL3 expression was 50% (interquartile range, 25%–70%). Thirty-four cases (52%) had ≥50% tumor cells positive for DLL3 expression with any intensity. Higher H-score of DLL3 expression was associated with higher polyomavirus nuclear expression (p = .003) when it was dichotomized to negative versus positive. H-score of DLL3 expression did not predict OS of patients with MCC (p = .4) after being adjusted for common clinicopathological factors. A patient treated with Rova-T for refractory metastatic MCC achieved partial response. Conclusions DLL3 overexpression is very common in MCC by immunohistochemistry. The response to treatment suggests that DLL3 expression may have predictive relevance for DLL3-targeting therapies in MCC. Implications for Practice Delta-like protein 3 (DLL3) is being developed as a predictive biomarker to identify patients for treatment with DLL3-targeting agents. Merkel cell carcinoma (MCC) is an aggressive neuroendocrine carcinoma of the skin. It was found that DLL3 overexpression is very common in MCC by immunohistochemistry and significantly associated with Merkel cell polyomavirus expression. Despite the lack of prognostic significance in this cohort, DLL3 expression may have predictive relevance for DLL3-targeting therapies in MCC. The high levels of DLL3 expression in a subset of MCC may potentially be used to select patients to receive DLL3-targeting therapies.