1- Versus 3-Month DAPT in Older Patients at a High Bleeding Risk Undergoing PCI: Insights from the XIENCE Short DAPT Global Program

This analysis aimed to evaluate the effect of 1- versus 3-month dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) in older patients. Data from 3 prospective, single-arm studies (XIENCE Short DAPT Program), including patients with high bleeding risk successfully treated with an everolimus-eluting stent (XIENCE, Abbott) were analyzed. DAPT was discontinued at 1 or at 3 months in patients free from ischemic events and adherent to DAPT. Patients were stratified according to age (≥75 and <75 years). The primary end point was all-cause death or myocardial infarction (MI). The key secondary end point was Bleeding Academic Research Consortium type 2 to 5 bleeding. The outcomes were assessed from 1 to 12 months after index PCI. Of 3,364 patients, 2,241 (66.6%) were aged ≥75 years. The risk of death or MI was similar with 1- versus 3-month DAPT in patients aged ≥75 (8.5% vs 8.0%, adjusted hazard ratio [HR] 0.95, 95% confidence interval [CI] 0.69 to 1.30) and <75 years (6.9% vs 7.8%, adjusted HR 0.97, 95% CI 0.60 to 1.57, interaction p = 0.478). Bleeding Academic Research Consortium type 2 to 5 bleeding was consistently lower with 1- than with 3-month DAPT in patients aged ≥75 years (7.2% vs 9.4%, adjusted HR 0.66, 95% CI 0.48 to 0.91) and <75 years (9.7% vs 11.9%, adjusted HR 0.86, 95% CI 0.57 to 1.29, interaction p = 0.737). In conclusion, in patients at high bleeding risk who underwent PCI, patients older and younger than 75 years derived a consistent benefit from 1- compared with 3-month DAPT in terms of bleeding reduction, with no increase in all-cause death or MI at 1 year.

1- or 3-Month DAPT in Patients With HBR With or Without Oral Anticoagulant Therapy After PCI

BACKGROUND

The optimal duration of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) in patients on long-term oral anticoagulation (OAC) therapy is still uncertain.

OBJECTIVES

The aim of this analysis was to assess the effects of 1- vs 3-month DAPT in patients with and those without concomitant OAC included in the XIENCE Short DAPT program.

METHODS

The XIENCE Short DAPT program enrolled patients with high bleeding risk who underwent successful PCI with a cobalt-chromium everolimus-eluting stent. DAPT was discontinued at 1 or 3 months in patients free from ischemic events and adherent to treatment. The effect of 1- vs 3-month DAPT was compared in patients with and those without OAC using propensity score stratification. The primary endpoint was all-cause death or any myocardial infarction (MI). The key secondary endpoint was Bleeding Academic Research Consortium (BARC) types 2 to 5 bleeding. Outcomes were assessed from 1 to 12 months after index PCI.

RESULTS

Among 3,364 event-free patients, 1,462 (43%) were on OAC. Among OAC patients, the risk for death or MI was similar between 1- and 3-month DAPT (7.4% vs 8.8%; adjusted HR: 0.74; 95% CI: 0.49-1.11; P = 0.139), whereas BARC types 2 to 5 bleeding was lower with 1-month DAPT (adjusted HR: 0.71; 95% CI: 0.51-0.99; P = 0.046). These effects were consistent in patients with and those without OAC (P for interaction = NS).

CONCLUSIONS

Between 1 and 12 months after PCI, 1-month compared with 3-month DAPT was associated with similar rates of all-cause death or MI and a reduced rate of BARC types 2 to 5 bleeding, irrespective of OAC treatment.

Analysis of Demographics and Outcomes of Surgical Resection in the Central Nervous System of Patients With Metastatic Melanoma

Background

Patients with melanoma frequently develop central nervous system metastases. Oligometastatic disease is often treated either by surgical resection or by stereotactic radiotherapy. This study investigates the trends and clinical outcomes of patients with melanoma who have undergone surgical procedures on the central nervous system during their hospitalization.

Methods

A retrospective study was performed based on admissions of adult patients who underwent craniotomy for metastatic melanoma from 2000 to 2014 using the Nationwide Inpatient Sample database. The primary outcome measure was all-cause in-hospital mortality. Secondary outcomes included hospital length of stay (LOS) and discharge disposition (home/home with health care and skilled nursing facilities/long-term acute care (SNFs/LTAC)). Factors associated with in-hospital mortality were examined by multivariable logistic regression. We adjusted for patient and hospital characteristics, payer, and comorbid conditions. We also examined trends of mortality for the study years.

Results

There were an estimated 1,216 discharges of patients with melanoma undergoing craniotomy during the study period. Patients undergoing surgical interventions were typically males (69%) and whites (79%). Ninety-eight percent of procedures were performed at teaching hospitals. Unadjusted all-cause in-hospital mortality was 3.1%. There was no significant difference in mortality over 13 years. Age, gender, and race were not associated with increased in-hospital mortality. LOS was longer in elderly and those with higher Charlson Comorbidity Index. Of the survivors, 76% were discharged to home or with home healthcare while 24% were discharged to SNFs/LTAC. Patients with age > 65 (odds ratio (OR): 2.9; 95% confidence interval (CI): 2.2 - 3.9, P < 0.001) and those with higher Charlson Comorbidity Index (OR: 1.2; 95% CI: 1.1 - 1.3) had higher odds for being discharged to SNFs/LTAC.

Conclusions

Patients who undergo craniotomy for metastatic melanoma have a low in-hospital mortality rate. One quarter of patients were discharged to SNFs/LTAC.

Efficacy of Rac and Cdc42 Inhibitor MBQ-167 in Triple-negative Breast Cancer

Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer, with a high predisposition for locally invasive and metastatic cancer. With the objective to reduce cancer metastasis, we developed small molecule inhibitors to target the drivers of metastasis, the Rho GTPases Rac and Cdc42. Of these, MBQ-167 inhibits both Rac and Cdc42 with IC50s of 103 and 78 nmol/L, respectively; and consequently, inhibits p21-activated kinase (PAK) signaling, metastatic cancer cell proliferation, migration, and mammosphere growth; induces cell-cycle arrest and apoptosis; and decreases HER2-type mammary fatpad tumor growth and metastasis (Humphries-Bickley and colleagues, 2017). Herein, we used nuclear magnetic resonance to show that MBQ-167 directly interacts with Rac1 to displace specific amino acids, and consequently inhibits Rac.GTP loading and viability in TNBC cell lines. Phosphokinome arrays in the MDA-MB-231 human TNBC cells show that phosphorylation status of kinases independent of the Rac/Cdc42/PAK pathway are not significantly changed following 200 nmol/L MBQ-167 treatment. Western blotting shows that initial increases in phospho-c-Jun and phospho-CREB in response to MBQ-167 are not sustained with prolonged exposure, as also confirmed by a decrease in their transcriptional targets. MBQ-167 inhibits tumor growth, and spontaneous and experimental metastasis in immunocompromised (human TNBC) and immunocompetent (mouse TNBC) models. Moreover, per oral administration of MBQ-167 at 100 mg/kg body weight is not toxic to immunocompetent BALB/c mice and has a half-life of 4.6 hours in plasma. These results highlight the specificity, potency, and bioavailability of MBQ-167, and support its clinical potential as a TNBC therapeutic.

Duration of Dual Antiplatelet Therapy for Patients at High Bleeding Risk Undergoing PCI

BACKGROUND

The optimal duration of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) among patients at high bleeding risk (HBR) is unknown.

OBJECTIVES

The purpose of this analysis was to compare 1 vs 3 months of DAPT in HBR patients undergoing drug-eluting stent implantation.

METHODS

The XIENCE Short DAPT program comprised 3 prospective, multicenter, single-arm studies of HBR patients treated with a short DAPT course followed by aspirin monotherapy after PCI with a cobalt-chromium everolimus-eluting stent. In this exploratory analysis, patients who received 1-month DAPT (XIENCE 28 USA and 28 Global) were compared with those on 3-month DAPT (XIENCE 90) using propensity score stratification. Ischemic and bleeding outcomes were assessed between 1 and 12 months after index PCI.

RESULTS

A total of 3,652 patients were enrolled and 1,392 patients after 1-month DAPT and 1,972 patients after 3-month DAPT were eligible for the analyses. The primary endpoint of all-cause mortality or myocardial infarction was similar between the 2 groups (7.3% vs 7.5%; difference -0.2%; 95% CI: -2.2% to 1.7%; P = 0.41). The key secondary endpoint of BARC (Bleeding Academic Research Consortium) type 2-5 bleeding was lower with 1-month DAPT compared with 3-month DAPT (7.6% vs 10.0%; difference -2.5%; 95% CI: -4.6% to -0.3%; P = 0.012). Major BARC type 3-5 bleeding did not differ at 12 months (3.6% vs 4.7%; difference -1.1%; 95% CI: -2.6% to 0.4%; P = 0.082), but was lower with 1-month DAPT at 90 days (1.0% vs 2.1%; P = 0.015).

CONCLUSIONS

Among HBR patients undergoing PCI, 1 month of DAPT, compared with 3 months of DAPT, was associated with similar ischemic outcomes and lower bleeding risk. (XIENCE 90 Study; NCT03218787; XIENCE 28 USA Study; NCT03815175; XIENCE 28 Global Study; NCT03355742).

Analysis of Trends in Mortality in Patients with Lymphoepithelial Carcinoma of the Head and Neck

Background

Squamous cell carcinoma is the most common subtype of malignancy found in patients with head and neck malignancy. There are other rare subtypes which are not adequately reported in medical literature. Lymphoepithelial carcinoma consists of lymphocytic infiltration in a background of undifferentiated carcinoma. They are most often seen in salivary glands but can also be found in other structures of the head and neck region. This analysis reports the nation-wide mortality of patients diagnosed with lymphoepithelial carcinoma of the head and neck.

Methods

Data were extracted from the Surveillance, Epidemiology, and End Results (SEER) Database from the years 2000 to 2014. Incidence-based mortality for all stages was queried and results were grouped by gender and race (Caucasian/White, African American/Black, American Indian/Alaskan native and Asian/Pacific Islander). Paired T-test was used to determine statistically significance difference between various subgroups.

Results

Incidence-based mortality has been improving for African American/Black patients and has been worsening for Caucasian/White, American Indian/Alaskan native and Asian/Pacific Islander for the period of 2000 to 2014. The differences in mortality trends were statistically different (P < 0.05). The highest mortality rate per 1000 patients was seen in Asian/Pacific Islander population, followed by African American/Black, American Indian/Alaskan native and the least mortality was noted in Caucasian/White patients. When a similar analysis with linearized trend lines on gender was conducted, only African American/Black males and Asian/Pacific Islander females showed an improving trend in mortality. The sample size was a major limitation of this study (Caucasian/White - 134, African American/Black - 30, American Indian/Alaskan native - 5 and Asian/Pacific Islander - 87).

Conclusion

Lymphoepithelial carcinoma is a rare subtype of head and neck malignancies whose incidence-based mortality showed a worsening trend. This study showed significant race and gender disparity amongst patients with lymphoepithelial carcinoma. Due to its rarity, this subtype warrants further study, especially with regards to its etiology, clinical course and cure rates.

3- or 1-Month DAPT in Patients at High Bleeding Risk Undergoing Everolimus-Eluting Stent Implantation

OBJECTIVES

The aim of this study was to evaluate 2 abbreviated dual-antiplatelet therapy (DAPT) regimens in patients at high bleeding risk (HBR) undergoing percutaneous coronary intervention (PCI).

BACKGROUND

Current-generation drug-eluting stents are preferred over bare-metal stents for HBR patients, but their optimal DAPT management remains unknown.

METHODS

The XIENCE Short DAPT program included 3 prospective, multicenter, single-arm studies enrolling HBR patients who underwent successful PCI with a cobalt-chromium everolimus-eluting stent. After 1 month (XIENCE 28 USA and XIENCE 28 Global) or 3 months (XIENCE 90) of DAPT, event-free patients discontinued the P2Y₁₂ inhibitor. The postmarketing approval XIENCE V USA study was used as historical control in a propensity score-stratified analysis.

RESULTS

A total of 3,652 patients were enrolled. The propensity-adjusted rate of the primary endpoint of all-cause mortality or myocardial infarction was 5.4% among 1,693 patients on 3-month DAPT versus 5.4% in the 12-month DAPT historical control (P_{noninferiority} = 0.0063) and 3.5% among 1,392 patients on 1-month DAPT versus 4.3% in the 6-month DAPT historical control (P_{noninferiority} = 0.0005). Bleeding Academic Research Consortium (BARC) types 2 to 5 bleeding was not significantly lower with 3- or 1-month DAPT, while BARC types 3 to 5 bleeding was reduced in both experimental groups. The rate of definite or probable stent thrombosis was 0.2% in XIENCE 90 (P < 0.0001 for the performance goal of 1.2%) and 0.3% in XIENCE 28.

CONCLUSIONS

Among HBR patients undergoing PCI with cobalt-chromium everolimus-eluting stents, DAPT for 1 or 3 months was noninferior to 6 or 12 months of DAPT for ischemic outcomes and may be associated with less major bleeding and a low incidence of stent thrombosis.

Cancer stem cells in head and neck cancer

Cancer stem cells (CSCs) are a unique population of cells found within tumors that are able to self-renew, restore the original heterogeneity of a tumor following treatment, and show increased tumorigenic potential when compared to other cancer cells. It is thought that they are responsible for the recurrence of tumors as well as the resistance to treatment that is seen clinically. CSCs are known to be involved in head and neck cancer (HNCs) specifically, as evidence for their existence can be found in head and neck squamous cell carcinoma (HNSCC), mucoepidermoid carcinoma (MEC), and adenoid cystic carcinoma (ACC), among others. Here, findings from various approaches to identifying and targeting CSCs and their downstream effectors in HNC are summarized, with an emphasis on recent advancements. Prognostic and therapeutic markers are discussed for each specific type of HNC, and novel treatment strategies and current clinical trials involving CSCs are detailed as well. The information provided here is intended to further the research on this important topic and lead to clinical impact in the battle against HNC.

Design and rationale of the XIENCE short DAPT clinical program: An assessment of the safety of 3-month and 1-month DAPT in patients at high bleeding risk undergoing PCI with an everolimus-eluting stent

Dual antiplatelet therapy (DAPT) is key for the prevention of recurrent ischemic events after percutaneous coronary intervention (PCI); however, it increases the risk of bleeding complications. While new generation drug-eluting stents have been shown superior to bare-metal stents after a short DAPT course, the optimal DAPT duration in patients at high bleeding risk (HBR) remains to be determined. TRIAL DESIGN: The XIENCE Short DAPT program consists of three prospective, single-arm studies (XIENCE 90, XIENCE 28 Global and XIENCE 28 USA) investigating 3- or 1-month DAPT durations in HBR patients undergoing PCI with the XIENCE stent. The XIENCE 90 study is being conducted in the US and enrolled 2047 subjects who discontinued DAPT at 3 months if they were free from myocardial infarction (MI), repeat coronary revascularization, stroke, or stent thrombosis. The XIENCE 28 program includes the USA study, enrolling 642 patients in US and Canada, and the Global study, enrolling 963 patients in Europe and Asia. In XIENCE 28, patients were to discontinue DAPT at 1 month post-PCI if event-free. The primary hypothesis for both XIENCE 90 and XIENCE 28 is that a short DAPT regimen will be non-inferior to a conventional DAPT duration with respect to the composite of all-cause death or MI. Patients enrolled in the prospective multicenter post-market XIENCE V USA study will be used as historical control group in a stratified propensity-adjusted analysis. CONCLUSIONS: The XIENCE Short DAPT Program will provide insights into the safety and efficacy of 2 abbreviated DAPT regimens of 3- and 1-month duration in a large cohort of HBR patients undergoing PCI with the XIENCE stent.

Mechanisms of resistance in head and neck cancer

Resistance to treatment is one of the biggest challenges in combating head and neck squamous cell carcinoma (HNSCC). The concept of resistance, however, is often viewed as a whole without categorization into the two types of resistance: acquired and intrinsic. Comparison of the mechanisms of the two types of resistance can give further insight as to the importance of these resistance pathways, as mechanisms that are common between the two categories are more likely to be integral to cell survival. In this review, a new perspective on resistance is presented in order to identify molecular targets that have potential for wide therapeutic application. Resistance mechanisms are grouped by the primary pathway involved in order to help establish connections between studies and identify the pathways most active in HNSCC resistance. The receptor tyrosine kinase AXL is one of the targets that showed the greatest promise for overcoming resistance to cetuximab, an antibody targeting the epidermal growth factor receptor (EGFR), as it is shown to be upregulated in both acquired and intrinsically cetuximab-resistant cells. Other targets of interest are signal transducer and activator of transcription 3 (STAT3), a downstream transcription factor of the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway, and TWIST, a marker of epithelial-mesenchymal transition. STAT3 has been shown to be upregulated and more active in cetuximab-resistant HNSCC cell lines, and its inhibition decreased cell growth in cell lines resistant to anti-EGFR therapy. Twist has been shown to have roles in acquired resistance for both cetuximab and cisplatin, a platinum-based therapy that targets dividing cells, which suggests that it also has an integral role in resistance. Other resistance mechanisms are also summarized in this review, but further studies are needed in order to confirm their utility as targets for overcoming resistance in HNSCC.

Abstract 5172: A functional genomic screen in vivo identifies CEACAM5 as a clinically relevant driver of breast cancer metastasis

Metastases are responsible for the vast majority of deaths due to breast cancer. Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer characterized by high rates of metastasis and poor prognosis. We are employing patient-derived xenograft (PDX) models of TNBC to identify drivers of metastasis. Tumor samples are obtained from the breast tumors of patients with TNBC and engrafted immediately into the humanized mammary fat pads of immune-compromised mice. Lentiviral transduction was employed to express bioluminescent and fluorescent markers in two independent PDX models of TNBC. Using these models, we demonstrated that human breast tumors are capable of completing all stages of the metastatic cascade in mice, and metastatic lesions are observed in organs normally found in patients with metastatic breast cancer including lung, liver, bone, brain, and lymph nodes. Dynamic and reversible shifts in the epithelial-to-mesenchymal transition (EMT) were observed as tumors metastasized to lung and were re-passaged to recipient mouse mammary fat pads (MFPs). Lung metastases were isolated using bioluminescence imaging and lung metastasis gene expression signatures were generated. Metastasis signatures from two independent PDX models were compared to identify genes that were commonly deregulated in lung metastases relative to corresponding mammary tumors. Comprehensive gain-of-function screens were then conducted in vivo to identify functional drivers of TNBC metastasis. Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) was identified as a metastatic driver in this screen. CEACAM5 mRNA and protein levels were elevated in lung metastases relative to corresponding MFP tumors in mice. In addition, we demonstrated that CEACAM5 expression was upregulated in the lung metastases of breast cancer patients, and its expression inversely correlated with patient survival. Our data indicate that the metastatic function of CEACAM5 is to promote growth of breast tumors in the lung by inducing MET (mesenchymal-to-epithelial transition).

Citation Format: Emily Powell, Jiansu Shao, Hector Picon, Christopher Bristow, Zhongqi Ge, Caitlin Grzeskowiak, Michael Peoples, Frederick Robinson, Sabrina Jeter-Jones, Christopher Schlosberg, Fei Yang, Yun Wu, Ignacio Wistuba, Stacy Moulder, Fraser Symmans, Kenneth Scott, John Edwards, Han Liang, Timothy Heffernan, Helen Piwnica-Worms. A functional genomic screen in vivo identifies CEACAM5 as a clinically relevant driver of breast cancer metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5172.