PKC-independent PI3K signalling diminishes PKC inhibitor sensitivity in uveal melanoma

Protein kinase C (PKC) is activated downstream of gain-of-function GNAQ or GNA11 (GNAQ/GNA11) mutations in over 90% of uveal melanoma (UM). Phase I clinical trials of PKC inhibitors have shown modest response rates with no survival benefit in metastatic UM. Although PKC inhibitors actively suppress mitogen-activated protein kinase (MAPK) signalling in UM, the effect on other UM signalling cascades is not well understood. We examined the transcriptome of UM biopsies collected pre- and post-PKC inhibitor therapy and confirmed that MAPK, but not PI3K/AKT signalling, was inhibited early during treatment with the second-generation PKC inhibitor IDE196. Similarly, in GNAQ/GNA11-mutant UM cell models, PKC inhibitor monotherapy effectively suppressed MAPK activity, but PI3K/AKT signalling remained active, and thus, concurrent inhibition of PKC and PI3K/AKT signalling was required to synergistically induce cell death in a panel of GNAQ/GNA11-mutant UM cell lines. We also show that re-activation of MAPK signalling has a dominant role in regulating PKC inhibitor responses in UM and that PI3K/AKT signalling diminishes UM cell sensitivity to PKC inhibitor monotherapy. Thus, combination therapies targeting PKC and PKC-independent signalling nodes, including PI3K/AKT activity, are required to improve responses in patients with metastatic UM.

Immune checkpoint inhibitor therapy for advanced cutaneous squamous cell carcinoma in Australia: a retrospective real world cohort study

OBJECTIVES

To review the outcomes of immune checkpoint inhibitor (ICI) treatment of advanced cutaneous squamous cell carcinoma (CSCC) outside clinical trials.

STUDY DESIGN

Retrospective observational study; review of patient records in fifteen Australian institutions.

SETTING, PARTICIPANTS

All Australian adults with locally advanced or metastatic CSCC not amenable to curative surgery or radiotherapy treated with ICIs, 5 May 2017 - 23 May 2022, through a cemiplimab compassionate access scheme (Therapeutic Goods Administration Special Access Scheme) or who personally covered the cost of pembrolizumab prior to the start of the access scheme.

MAIN OUTCOME MEASURES

Best overall response rate (ORR) according to standardised assessment criteria using the hierarchy: Response Evaluation Criteria in Solid Tumors (RECIST 1.1), the modified World Health Organization clinical response criteria, and the Positron Emission Tomography Response Criteria (PERCIST 1.0); overall and progression-free survival.

RESULTS

A total of 286 people with advanced CSCC received ICI therapy during May 2017 - May 2022 (cemiplimab, 270; pembrolizumab, 16). Their median age was 75.2 years (range, 39.3-97.5 years) and 232 were men (81%); median follow-up time was 12.2 months (interquartile range, 5.5-20.5 months). Eighty-eight people (31%) were immunocompromised, 27 had autoimmune disease, and 59 of 277 (21%) had ECOG performance scores of 2 or 3. The ORR was 60% (166 of 278 evaluable patients): complete responses were recorded for 74 (27%) and partial responses for 92 patients (33%). Twelve-month overall survival was 78% (95% confidence interval [CI], 72-83%); progression-free survival was 65% (95% CI, 58-70%). Poorer ECOG performance status was associated with poorer overall survival (per unit: adjusted hazard ratio [aHR], 3.0; 95% CI, 2.0-4.3) and progression-free survival (aHR, 2.4; 95% CI, 1.8-3.3), as was being immunocompromised (overall: aHR, 1.8; 95% CI, 1.1-3.0; progression-free: aHR, 1.8; 95% CI, 1.2-2.7). Fifty-five people (19%) reported immune-related adverse events of grade 2 or higher; there were no treatment-related deaths.

CONCLUSION

In our retrospective study, the effectiveness and toxicity of ICI therapy were similar to those determined in clinical trials. Our findings suggest that ICIs could be effective and well tolerated by people with advanced CSCC who are ineligible for clinical trials.

Coil or Plug-Assisted Ethylene Vinyl Alcohol Copolymer (EVOH) Thoracic Duct Embolization in the Treatment of Postoperative Chylothorax

Eleven patients (5 men, 6 women) with post-operative thoracic duct injuries and high output chylothorax were treated with thoracic duct embolization (TDE). Six patients underwent intraprocedural thoracic duct ligation at the time of original procedure. In all cases, the pleural fluid demonstrated high triglyceride levels (414 mg/dL; interquartile range [IQR], 345 mg/dL). Median daily (IQR) chest tube outputs before and after TDE were 900 mL (1,200 mL) and 325 mL (630 mL), respectively. Coil- or plug-assisted ethylene vinyl alcohol (EVOH) copolymer was used as embolic agent in all patients. Technical and clinical success rates were 100% and 82%, respectively. Nontarget venous embolization of EVOH copolymer was not identified on subsequent imaging.

Operator radiation exposure during radioembolisation of the liver: transfemoral versus transradial access using real-time dose monitoring

In this study, operator radiation exposure is compared utilising transradial access (TRA) versus transfemoral access (TFA) during transarterial radioembolisation (TARE) of liver tumors. Patients who underwent Y90 TARE between May 2017 and April 2018 were included. Electronic medical records and interventional data were collected and the following parameters evaluated: technical success, fluoroscopy time, operator radiation exposure and rate of operator radiation exposure per fluoroscopy time. Statistical analysis was performed with the Wilcoxon rank-sum test. A total of 22 patients (12 males, 10 females) underwent 22 procedures. A total of 12 procedures were performed via TFA and 10 via TRA. Technical success was 100% in both groups. Median fluoroscopy time (10 minutes for TRA vs 6.4 minutes for TFA, p = 0.082) was not statistically different. Both operator radiation exposure (49 vs 4.2 μSv, p = 0.00016) and rate of operator exposure (4.9 vs 0.71 μSv per min, p = 0.00021) were significantly higher in the TRA versus TFA groups, respectively.

A first-in-human phase 1 study of nofazinlimab, an anti-PD-1 antibody, in advanced solid tumors and in combination with regorafenib in metastatic colorectal cancer

BACKGROUND

We assessed nofazinlimab, an anti-PD-1 antibody, in solid tumors and combined with regorafenib in metastatic colorectal cancer (mCRC).

METHODS

This phase 1 study comprised nofazinlimab dose escalation (phase 1a) and expansion (phase 1b), and regorafenib dose escalation (80 or 120 mg QD, days 1-21 of 28-day cycles) combined with 300-mg nofazinlimab Q4W (part 2a) to determine safety, efficacy, and RP2D.

RESULTS

In phase 1a (N = 21), no dose-limiting toxicity occurred from 1 to 10 mg/kg Q3W, with 200 mg Q3W determined as the monotherapy RP2D. In phase 1b (N = 87), 400-mg Q6W and 200-mg Q3W regimens were found comparable. In part 2a (N = 14), both regimens were deemed plausible RP2Ds. Fatigue was the most frequent treatment-emergent adverse event (AE) in this study. Any-grade and grade 3/4 nofazinlimab-related AEs were 71.4% and 14.3%, 56.3% and 5.7%, and 57.1% and 21.4% in phases 1a, 1b, and part 2a, respectively. ORRs were 14.3% and 25.3% in phases 1a and 1b, respectively. In part 2a, no patients had radiological responses.

CONCLUSIONS

Nofazinlimab monotherapy was well tolerated and demonstrated preliminary anti-tumor activity in multiple tumor types. Regorafenib plus nofazinlimab had a manageable safety profile but was not associated with any response in mCRC.

CLINICAL TRIAL REGISTR ATION

Clinicaltrials.gov (NCT03475251).

A phase I trial of LXS196, a protein kinase C (PKC) inhibitor, for metastatic uveal melanoma

BACKGROUND

Up to 50% of patients with uveal melanoma develop metastases (MUM) with a poor prognosis and median overall survival of approximately 1 year.

METHODS

This phase I study evaluated the safety, tolerability, pharmacokinetics, pharmacodynamics and efficacy of the oral protein kinase C inhibitor LXS196 in 68 patients with MUM (NCT02601378). Patients received LXS196 doses ranging from 100-1000 mg once daily (QD; n = 38) and 200-400 mg twice daily (BID; n = 30).

RESULTS

First cycle dose-limiting toxicities (DLTs) were observed in 7/38 (18.4%) QD and 2/17 (11.8%) BID patients. Hypotension was the most common DLT, occurring at doses ≥500 mg/day, and manageable with LXS196 interruption and dose reduction. Median duration of exposure to LXS196 was 3.71 months (range: 1.81-15.28) for QD and 4.6 months (range: 0.33-58.32) for BID dosing. Clinical activity was observed in 6/66 (9.1%) evaluable patients achieving response (CR/PR), with a median duration of response of 10.15 months (range: 2.99-41.95); 45/66 had stable disease (SD) per RECIST v1.1. At 300 mg BID, the recommended dose for expansion, 2/18 (11.1%) evaluable patients achieved PR and 12/18 (66.7%) had SD.

CONCLUSION

These results suggest manageable toxicity and encouraging clinical activity of single-agent LXS196 in patients with MUM.

Use of Botulinum Toxin Injections for the Treatment of Chronic Anal Fissure: Results From an American Society of Colon and Rectal Surgeons Survey

BACKGROUND

Chronic anal fissure (CAF) is commonly treated by colorectal surgeons. Pharmacological treatment is considered first-line therapy. An alternative treatment modality is chemical sphincterotomy with injection of botulinum toxin (BT). However, there is a lack of a consensus on the BT administration procedure among colorectal surgeons.

METHODS

A national survey approved by the American Society of Colon and Rectal Surgeons (ASCRS) Executive Council was sent to all members. An eight-question survey was sent via ASCRS email correspondence between December 2019 and February 2020. Questions were derived from available meta-analyses and expert opinions on BT use in CAF patients and included topics such as BT dose, injection technique, and concomitant therapies. The survey was voluntary and anonymous, and all ASCRS members were eligible to complete it. Responses were recorded and analyzed via an online survey platform.

RESULTS

216 ASCRS members responded to the survey and 90% inject 50-100U of BT. Most procedures are performed under MAC anesthesia (56%). A majority of respondents (64%) inject into the internal sphincter and a majority (53%) inject into 4 quadrants in the anal canal circumference. Some respondents perform concomitant manual dilatation (34%) or fissurectomy (38%). Concomitant topical muscle relaxing agents are not used uniformly among respondents.

DISCUSSION

Injection of BT for CAF is used commonly by colorectal surgeons. There is consensus on BT dosage, administration site, technique, and the use of monitored anesthesia care.

Temporary Vascular Occlusion with Retrievable Microvascular Plugs to Protect Normal Liver during Yttrium-90 Radioembolization

This case series describes a technique to protect nondiseased liver parenchyma during transarterial radioembolization (TARE) using microvascular plugs to occlude nontarget vessels temporarily and protect normal liver. This technique, defined as temporary vascular occlusion, was performed in 6 patients, with complete vessel occlusion obtained in 5 of the 6 patients and partial occlusion with flow reduction in 1 of the 6 patients. A statistically significant (P = .001) dose decrease of 5.7 ± 3.1 times was measured using postadministration yttrium-90 positron emission tomography/computed tomography in the protected zone compared with that in the treated zone.

Case Series: "Silent" Spinal Epidural Metastases in Metastatic Castrate-Resistant Prostate Cancer

Introduction

Spinal epidural metastases (SEM) are an uncommon phenomenon and traditionally occur as a preterminal event in heavily pre-treated patients. The introduction of novel anti-androgen therapies, such as enzalutamide and abiraterone acetate, has greatly improved the survival of patients with metastatic prostate cancer but may be changing the pattern of disease.

Case Presentation

Four patients diagnosed with metastatic castrate-resistant prostate cancer (CRPC) were commenced on enzalutamide prior to chemotherapy. Baseline scans in all patients demonstrated extensive bony disease and lymph node involvement. All patients experienced a moderate initial PSA response to treatment (median PSA at baseline 53.5 ng/mL to median nadir 24.5 ng/mL). In all four cases, clinical presentation of spinal cord compression was unexpected with no prodromal neurological symptoms, PSA levels either stable or slowly rising, and CT scans and whole-body bone scans showing stable disease at other metastatic sites. Whole-spine MRI on presentation of neurological deficits showed epidural and dural metastases on the background of stable bone disease. Spinal cord compression occurred at a median of 11.4 months after starting enzalutamide.

Conclusion

Clinicians should be aware of this change in the pattern of CRPC in patients treated with novel anti-androgen therapy. Onset of "silent" spinal cord compression due to SEM rather than bone metastases, can occur relatively early with minimal warning despite stable disease on PSA and standard imaging. Differential progression in nontraditional sites suggests that research into the androgen microenvironment in a wide range of tissue sites should be undertaken, and may explain why prostate cancer metastasizes preferentially to bone and lymph nodes.

Protein kinase inhibitor responses in uveal melanoma reflects a diminished dependency on PKC-MAPK signaling

Uveal melanoma (UM) is a rare cancer arising from melanocytes in the uveal tract of the eye. Despite effective primary treatment, there is no approved therapy for metastatic UM and prognosis and survival remain poor. Over 90% of UM are driven by mutations affecting the Gα subunits encoded by the GNAQ and GNA11 genes. These mutations activate downstream and targetable signaling pathways, including the protein kinase C (PKC) cascade. PKC inhibitors have been used in clinical trials for metastatic UM but have shown limited efficacy. In this study, we examined the signaling and functional effects of two PKC inhibitors (AEB071 and IDE196) in a panel of UM cell models. In response to PKC inhibition, all UM cell lines showed potent suppression of PKC activity, but this was not sufficient to predict PKC inhibitor sensitivity and only two UM cell lines showed substantial PKC inhibitor-induced cell death. The differences in UM cell responses to PKC inhibition were not attributable to the degree or timing of PKC suppression or inhibition of the downstream mitogen-activated protein kinase (MAPK) or phosphatidylinositol-3-kinase (PI3K) pathways. Instead, UM cell show complex, PKC-independent signaling pathways that contribute to their survival and resistance to targeted therapies.

Importance of catecholamine signaling in the development of platelet exhaustion after traumatic injury

BACKGROUND

Impaired ex vivo platelet aggregation is common in trauma patients. The mechanisms driving these impairments remain incompletely understood, but functional platelet exhaustion due to excessive in vivo activation is implicated. Given platelet adrenoreceptors and known catecholamine surges after injury, impaired ex vivo platelet aggregation in trauma patients may be linked to catecholamine-induced functional platelet exhaustion.

OBJECTIVE

To determine the relationship of catecholamines with platelet-dependent hemostasis after injury and to model catecholamine-induced functional platelet exhaustion in healthy donor platelets.

PATIENTS/METHODS

Whole blood was collected from 67 trauma patients as part of a prospective cohort study. Platelet aggregometry and rotational thromboelastometry were performed, and plasma epinephrine (EPI) and norepinephrine (NE) concentrations were measured. The effect of catecholamines on healthy donor platelets was examined in a microfluidic model, with platelet aggregometry, and by flow cytometry examining surface markers of platelet activation.

RESULTS

In trauma patients, EPI and NE were associated with impaired platelet aggregation (both p < 0.05), and EPI was additionally associated with decreased viscoelastic clot strength, increased fibrinolysis, and mortality (all p < 0.05). In healthy donors, short duration incubation with EPI enhanced platelet aggregation, platelet adhesion under flow, and increased glycoprotein IIb/IIIa activation, while weaker effects were observed with NE. Compared with short incubation, longer incubation with EPI resulted in decreased platelet adhesion, platelet aggregation, and surface expression of glycoprotein IIb/IIIa.

CONCLUSIONS

These findings suggest sympathoadrenal activation in trauma patients contributes to impaired ex vivo platelet aggregation, which mechanistically may be explained by a functionally exhausted platelet phenotype under prolonged exposure to high plasma catecholamine levels.

Leveraging metabolic modeling to identify functional metabolic alterations associated with COVID-19 disease severity

OBJECTIVE

Since the COVID-19 pandemic began in early 2020, SARS-CoV2 has claimed more than six million lives world-wide, with over 510 million cases to date. To reduce healthcare burden, we must investigate how to prevent non-acute disease from progressing to severe infection requiring hospitalization.

METHODS

To achieve this goal, we investigated metabolic signatures of both non-acute (out-patient) and severe (requiring hospitalization) COVID-19 samples by profiling the associated plasma metabolomes of 84 COVID-19 positive University of Virginia hospital patients. We utilized supervised and unsupervised machine learning and metabolic modeling approaches to identify key metabolic drivers that are predictive of COVID-19 disease severity. Using metabolic pathway enrichment analysis, we explored potential metabolic mechanisms that link these markers to disease progression.

RESULTS

Enriched metabolites associated with tryptophan in non-acute COVID-19 samples suggest mitigated innate immune system inflammatory response and immunopathology related lung damage prevention. Increased prevalence of histidine- and ketone-related metabolism in severe COVID-19 samples offers potential mechanistic insight to musculoskeletal degeneration-induced muscular weakness and host metabolism that has been hijacked by SARS-CoV2 infection to increase viral replication and invasion.

CONCLUSIONS

Our findings highlight the metabolic transition from an innate immune response coupled with inflammatory pathway inhibition in non-acute infection to rampant inflammation and associated metabolic systemic dysfunction in severe COVID-19.

A phase I dose-escalation and expansion study of HBM4003, an anti-CTLA-4 heavy chain only monoclonal antibody, in patients with advanced solid tumors

2641

Background: HBM4003 is a fully human heavy chain only monoclonal antibody (HCAb) to CTLA-4, which has been engineered to deplete Treg cells by enhanced antibody-dependent cellular cytotoxicity (ADCC) activity. In the Phase 1 dose escalation part, HBM4003 showed favorable safety and efficacy profile in patients (pts) with advanced solid tumors. Here, we present the updated data from the dose escalation part and most recent safety and clinical activity data from three expansion cohorts of pts with advanced hepatocellular carcinoma (HCC), melanoma, and renal cell carcinoma (RCC). Methods: In the dose-escalation part, pts were enrolled into 3 dose levels (DL): 0.3mg/kg QW (28-day cycle), 0.45mg/kg Q3W (21-day cycle), and 0.6mg/kg Q3W (21-day cycle). In the dose-expansion part, pts with advanced HCC, melanoma, and RCC received 0.45 mg/kg Q3W (21-day cycle). Tumor measurements were performed every 6 weeks for up to 12 months and subsequently every 12 weeks per RECIST v1.1. Results: In total 60 pts were included for this analysis, including 24 pts with advanced solid tumors in the dose escalation part and 36 pts in the dose expansion part: 18 pts with HCC, 4 pts with melanoma, and 14 pts with RCC, from 12 sites in mainland China, 5 sites in Australia, and 1 site in Hong Kong. 46 pts (77%) received ≥ 2 lines of previous systemic therapies and 37 pts (62%) received previous PD-1/PD-L1 treatment. For the HCC cohort, 19 pts were treated in dose-escalation (1 pt, 0.45 mg/kg Q3W) and dose-expansion parts. All 19 pts received previous PD-1/PD-L1 therapy. 12 pts were evaluable for efficacy. Two had stable disease (SD), 2 pts had partial response (PR) as best response. For 12 evaluable pts, ORR was 16.7% and disease control rate (DCR) was 33.3%. For the RCC cohort, 19 pts were treated in dose-escalation and dose-expansion parts; 18 pts were evaluable for efficacy. Eight had SD as best response; the DCR was 44.4%. Overall, the most common treatment-related adverse event (TRAE) (incidence ≥ 10%) of all grades was rash (16 [26.7%] pts). At the 0.45 mg/kg Q3W DL, the most common TRAE of all grades was hepatic function abnormalities (12 [27.9%] pts) and rash (12 [27.9%] pts). 30 (69.8%) pts reported Gr 1 or 2 TRAEs. Gr ≥3 TRAEs occurred in 4 (9.3%) pts. 1 pt reported Gr 4 TRAE: blood creatine phosphokinase increased. No Gr 5 TRAE was reported. TRAE leading to discontinuation occurred in 4 pts. In mouse model, only tumor infiltrating lymphocytes Treg was depleted upon HBM4003 treatment while no Treg change in blood and spleen. In pts, Treg depletion was observed only in tumor tissue on day 21 post dosing. Overall, HBM4003 demonstrated dose proportional pharmacokinetics and low immunogenicity. Conclusions: HBM4003 showed a favorable safety profile, promising antitumor activity and intratumoral Treg depletion in pts with advanced solid tumors at the 0.45 mg/kg Q3W DL. Clinical trial information: NCT04135261.

IMPRINTER: An open label, multicenter, dose escalation/expansion, phase 1 study of imu-201 (PD1-Vaxx), a B-cell immunotherapy as monotherapy or in combination with atezolizumab, in adults with non-small cell lung cancer (IMU.201.101)

e21134

Background: Therapies with monoclonal antibodies targeting PD-1 and its ligands are associated with remarkable outcomes and have revolutionized cancer treatment (Honey 2017). However, patients treated with PD-1/PD-L1 blockade may develop “a primary or secondary resistance” to therapy (Sharma, Hu-Lieskovan et al. 2017). Contrary to monoclonal antibodies, chimeric B-cell cancer vaccines have the advantage of producing polyclonal B-cell antibodies that can potentially induce memory B- and T-cell responses, while reducing immune evasion and suppression. The hypothesis is that a polyclonal induced B-cell antibody response will be more effective or as effective with improved safety over current monoclonal antibody therapy. IMU-201 (PD1-Vaxx) is being developed using an active immunization approach to treat cancers that overexpress PD-L1 by inducing the production of anti-PD-1 antibodies with a peptide epitope designed to stimulate polyclonal antibodies against PD-1 (Kaumaya et al. 2020). Methods: The IMPRINTER study is an ongoing open-label dose escalation study of IMU-201 as monotherapy (Phase 1) or in combination with atezolizumab (Phase 1b) for patients with PD-L1 expressing non-small cell lung cancer (NSCLC). All patients enrolled in Phase 1 of the study must have previously received an immune checkpoint inhibitor and experienced disease progression. The primary objective is to evaluate the safety and tolerability of IMU-201 and identify the optimal biological dose (OBD). The secondary objective is to evaluate the efficacy of IMU-201 as monotherapy and in combination with atezolizumab. Humoral and cellular immunogenicity data will be evaluated, including IMU-201 and PD-1 specific antibodies (IgG, IgM), vaccine-specific cytokine levels, and regulatory and effector T and B cells. IMU-201 is administered by intramuscular (IM) injection on Day 1, Day 15, and Day 29. Dose-limiting toxicity (DLT) assessment is completed after 29 days on treatment. Tumor progression is evaluated according to RECIST 1.1 at Day 43 then every 42 days until progression or withdrawal. Results: In Phase 1, four patients were enrolled into each of the three cohorts at 10 μg/dose, 50 μg/dose and 100 μg/dose IMU-201 with no DLTs observed. In the 10 μg/dose cohort, one patient achieved CR and one patient SD; in the 50 μg/dose cohort, four patients achieved SD; and in the 100 μg/dose cohort, one patient achieved PR and two patients achieved SD. Within the 100 μg/dose cohort, one patient experienced an immune related pneumonitis after two IMU-201 administrations and discontinued from study treatment. Conclusions: IMU-201 had no observed DLT and demonstrated preliminary signs of efficacy. The study will therefore move into Phase 1b with IMU-201 being assessed in combination with atezolizumab. Clinical trial information: NCT04432207.

Safety and efficacy of YBL-006, an anti-PD-1 monoclonal antibody in advanced solid tumors: A phase I study

e14557

Background: YBL-006 is a fully human anti-programmed death-1 (PD-1) antibody under evaluating its safety and efficacy in phase I clinical trial. We have reported interim analysis of dose escalation cohort which showed a tolerable safety profile. Here, we present the updated clinical activity of YBL-006 in dose escalation and expansion cohorts. Methods: Dose escalation (0.5, 2, 5, 10 mg/kg) and dose expansion (flat doses of 200 mg every 2 weeks [Q2W] and 300 mg every 3 weeks [Q3W]) cohorts explored the safety, pharmacokinetics (PK) and objective response rate (ORR) in the patients with advanced solid tumors who failed or were ineligible to the standard of care. Adverse events (AEs) were graded using the CTCAE v5. ORR was assessed using the RECIST (v1.1). Lunit SCOPE IO, an H&E analysis tool, was applied as an exploratory biomarker, and samples with “Immune inflamed phenotype” were defined as those with high intratumoral TIL density in ≥ 20% of the tumor microenvironment. The cut-off date for analysis was Jan 4th, 2022. Results: A total of 67 patients (safety set) with advanced solid tumors were enrolled in the study. Median follow-up duration of the safety set was 1.6 months (range 0.2-16.8). There was no dose-limiting toxicity during dose escalation phase. Most frequent AEs were grade 1 or 2; fatigue (19.4%), pruritus (10.4%), and fever (7.5%), and two hypothyroidism (3.0%), one pneumonitis (1.5%), and one cytokine-releasing syndrome (1.5%) were observed. One subject experienced grade 3 diarrhea in the safety set. PK study showed that half-life was 8.0 days, and mean Cmax and AUC0-inf were 4.15 x 104 ng/ml and 1.12 x 107 ng/ml*h for 200 mg dose, and 6.26 x 104 ng/ml and 1.53 x 107 ng/ml*h for 300 mg dose, respectively. A total of 52 patients were evaluable for efficacy. ORR was 15.4%, including 1 complete response (penile squamous cell carcinoma [SqCC]), and 7 partial responses (two gastric adenocarcinomas, anal SqCC, paranasal sinus SqCC, nasopharyngeal carcinoma, neuroendocrine carcinoma, and thyroid Hurthle cell carcinoma). Durable responses were seen in 2 patients for over 12 months. Median duration of response was 4.9 weeks (range 1-65). Among efficacy set, 32 samples were available for Lunit SCOPE IO. ORR was significantly higher in inflamed immune phenotype compared to non-inflamed samples (62.5% vs 8.3% p = 0.005). Conclusions: Interim analysis of phase I trial of YBL-006 shows a tolerable safety profile and clinical activity. Notable anti-tumor efficacy was observed in inflamed immune phenotype. Clinical trial information: NCT04450901.

TACTI-003: A randomized phase IIb study of eftilagimod alpha (soluble LAG-3 protein) and pembrolizumab as first-line treatment of patients with recurrent or metastatic head and neck squamous cell carcinoma

TPS6099

Background: Eftilagimod alpha (efti) is a soluble LAG-3 protein targeting a subset of MHC class II molecules that mediate antigen presenting cell (APC) and CD8 T-cell activation. Data from a non-randomized, phase II trial of efti plus pembrolizumab (TACTI-002) showed encouraging antitumor activity and manageable safety when given as second-line treatment of patients with recurrent or metastatic head and neck squamous-cell carcinoma (RM-HNSCC). TACTI-003 (NCT04811027) is a multicenter, open label, randomized phase IIb trial to investigate efti plus pembrolizumab in the first-line setting for RM-HNSCC. Methods: A total of 154 patients (pts) are currently being recruited into two cohorts (A+B). In cohort A, pts with tumors that are CPS≥1 will be randomly assigned 1:1 to receive either efti (30 mg subcutaneously Q2W for initial 6 months, thereafter Q3W) plus pembrolizumab (400 mg intravenously Q6W) for up to two years or pembrolizumab alone. Randomization will be stratified by CPS (1-19 vs. ≥ 20) and ECOG PS (0 vs. 1). Pts with tumors that are CPS < 1 will receive efti plus pembrolizumab (cohort B). Imaging will be performed every 9 weeks. The primary endpoint (EP) is objective response rate (ORR) by RECIST1.1. Secondary EPs include overall survival, ORR according to iRECIST, time to and duration of response, disease control rate, progression-free survival, occurrence of anti-efti -specific antibodies, safety, and quality of life. Exploratory endpoints comprise biomarkers. The study has been approved by relevant competent authorities, ethic committees and IRBs. Clinical trial information: NCT04811027.

Disparities in Screening for Colorectal Cancer Based on Limited Language Proficiency

BACKGROUND

This study analyzes the association between limited language proficiency and screening for colorectal cancer.

METHODS

This is a retrospective cohort study from the 2015 sample of the National Health Interview Survey database utilizing univariate and multivariate regression analysis. The study population includes subjects between 50 and 75 years of age. The main outcome analyzed was rates of screening colonoscopies between limited English-language proficiency (LEP) subjects and those fluent in English. Secondary outcomes included analysis of baseline, socioeconomic, access to health care variables, and other modalities for colorectal cancer screening between the groups.

RESULTS

Incidence of limited language proficiency was 4.8% (n = 1978, count = 4 453 599). They reported lower rates of screening colonoscopies (61% vs 34%, P < .001), less physician recommendation for a colonoscopy (87 vs 60%, P < .001), fewer polyps removed in the previous 3 years (24% vs 9.1%; P < .001), and fewer fecal occult blood samples overall (P < .001). Additionally, Hispanic non-LEP subjects have higher rates of colonoscopies compared to those with language barriers (50% vs 33%, P < .001). On multivariate analysis, LEP was associated with a lower likelihood to have a screening colonoscopy (OR .67 95% CI .49-.91). A second regression model with "Spanish language" and "other language" variables included, associated Spanish speakers with a lower likelihood for a screening colonoscopy (OR .71 95% CI .52-.97) when controlling for baseline, socioeconomic, and access to health care covariates.

DISCUSSION

Patients with limited English-language proficiency are associated with lower rates of screening for colorectal cancer, in particular the Spanish speaking subgroup.

Correlation of Tumor Response Between Flexible Sigmoidoscopy and Magnetic Resonance Imaging in Patients Undergoing Neoadjuvant Therapy for Locally Advanced Rectal Cancer: A Retrospective Review

BACKGROUND

The National Accreditation Program for Rectal Cancer recommends a pelvic MRI to assess the response to neoadjuvant therapy for advanced rectal cancers. However, there is no single restaging modality that can identify all patients with complete tumor response. At our institution, we perform both a pelvic MRI and a flexible sigmoidoscopy (FS) after neoadjuvant therapy prior to surgical resection.

OBJECTIVE

The objective is to elucidate the correlation of tumor response between FS and MRI in patients undergoing neoadjuvant therapy for locally advanced rectal cancer.

DESIGN

Single institution from 2010 to 2019. Retrospective cohort study comparing local tumor response on FS to MRI utilizing final pathology as the gold standard for comparison.

PATIENTS

Patients with confirmed locally advanced rectal adenocarcinoma (stage II or III) who underwent neoadjuvant therapy prior to surgical intervention and underwent flexible endoscopy and a standardized rectal cancer protocol MRI to evaluate tumor response.

RESULTS

A total of 48 patients were evaluated. Seven (14%) patients had a complete pathological response. MRI adequately reported 1 (14%), while FS found 4 (57.14%) out of the 7 complete responders. Nevertheless, this did not reach statistical significance (P = .06). On logistic regression analysis, flexible sigmoidoscopy had a 5.5 higher likelihood to report an accurate complete response (OR 5.5, 95% CI: 1.02-29.64; P = .047).

CONCLUSIONS

Flexible sigmoidoscopy should be used in conjunction with MRI in the work up of patients who have received neoadjuvant therapy for advanced rectal cancer prior to surgical resection.

Clinical Models to Define Response and Survival With Anti-PD-1 Antibodies Alone or Combined With Ipilimumab in Metastatic Melanoma

PURPOSE

Currently, there are no robust biomarkers that predict immunotherapy outcomes in metastatic melanoma. We sought to build multivariable predictive models for response and survival to anti-programmed cell death protein 1 (anti-PD-1) monotherapy or in combination with anticytotoxic T-cell lymphocyte-4 (ipilimumab [IPI]; anti-PD-1 ± IPI) by including routine clinical data available at the point of treatment initiation.

METHODS

One thousand six hundred forty-four patients with metastatic melanoma treated with anti-PD-1 ± IPI at 16 centers from Australia, the United States, and Europe were included. Demographics, disease characteristics, and baseline blood parameters were analyzed. The end points of this study were objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). The final predictive models for ORR, PFS, and OS were determined through penalized regression methodology (least absolute shrinkage and selection operator method) to select the most significant predictors for all three outcomes (discovery cohort, N = 633). Each model was validated internally and externally in two independent cohorts (validation-1 [N = 419] and validation-2 [N = 592]) and nomograms were created.

RESULTS

The final model for predicting ORR (area under the curve [AUC] = 0.71) in immunotherapy-treated patients included the following clinical parameters: Eastern Cooperative Oncology Group Performance Status, presence/absence of liver and lung metastases, serum lactate dehydrogenase, blood neutrophil-lymphocyte ratio, therapy (monotherapy/combination), and line of treatment. The final predictive models for PFS (AUC = 0.68) and OS (AUC = 0.77) included the same variables as those in the ORR model (except for presence/absence of lung metastases), and included presence/absence of brain metastases and blood hemoglobin. Nomogram calculators were developed from the clinical models to predict outcomes for patients with metastatic melanoma treated with anti-PD-1 ± IPI.

CONCLUSION

Newly developed combinations of routinely collected baseline clinical factors predict the response and survival outcomes of patients with metastatic melanoma treated with immunotherapy and may serve as valuable tools for clinical decision making.

Therapeutic Anticoagulation with Heparin in Critically Ill Patients with Covid-19

BACKGROUND

Thrombosis and inflammation may contribute to morbidity and mortality among patients with coronavirus disease 2019 (Covid-19). We hypothesized that therapeutic-dose anticoagulation would improve outcomes in critically ill patients with Covid-19.

METHODS

In an open-label, adaptive, multiplatform, randomized clinical trial, critically ill patients with severe Covid-19 were randomly assigned to a pragmatically defined regimen of either therapeutic-dose anticoagulation with heparin or pharmacologic thromboprophylaxis in accordance with local usual care. The primary outcome was organ support-free days, evaluated on an ordinal scale that combined in-hospital death (assigned a value of -1) and the number of days free of cardiovascular or respiratory organ support up to day 21 among patients who survived to hospital discharge.

RESULTS

The trial was stopped when the prespecified criterion for futility was met for therapeutic-dose anticoagulation. Data on the primary outcome were available for 1098 patients (534 assigned to therapeutic-dose anticoagulation and 564 assigned to usual-care thromboprophylaxis). The median value for organ support-free days was 1 (interquartile range, -1 to 16) among the patients assigned to therapeutic-dose anticoagulation and was 4 (interquartile range, -1 to 16) among the patients assigned to usual-care thromboprophylaxis (adjusted proportional odds ratio, 0.83; 95% credible interval, 0.67 to 1.03; posterior probability of futility [defined as an odds ratio <1.2], 99.9%). The percentage of patients who survived to hospital discharge was similar in the two groups (62.7% and 64.5%, respectively; adjusted odds ratio, 0.84; 95% credible interval, 0.64 to 1.11). Major bleeding occurred in 3.8% of the patients assigned to therapeutic-dose anticoagulation and in 2.3% of those assigned to usual-care pharmacologic thromboprophylaxis.

CONCLUSIONS

In critically ill patients with Covid-19, an initial strategy of therapeutic-dose anticoagulation with heparin did not result in a greater probability of survival to hospital discharge or a greater number of days free of cardiovascular or respiratory organ support than did usual-care pharmacologic thromboprophylaxis. (REMAP-CAP, ACTIV-4a, and ATTACC ClinicalTrials.gov numbers, NCT02735707, NCT04505774, NCT04359277, and NCT04372589.).

Outcomes after ultramassive transfusion in the modern era: An Eastern Association for the Surgery of Trauma multicenter study

BACKGROUND

Despite the widespread institution of modern massive transfusion protocols with balanced blood product ratios, survival for patients with traumatic hemorrhage receiving ultramassive transfusion (UMT) (defined as ≥20 U of packed red blood cells [RBCs]) in 24 hours) remains low and resource consumption remains high. Therefore, we aimed to identify factors associated with mortality in trauma patients receiving UMT in the modern resuscitation era.

METHODS

An Eastern Association for the Surgery of Trauma multicenter retrospective study of 461 trauma patients from 17 trauma centers who received ≥20 U of RBCs in 24 hours was performed (2014-2019). Multivariable logistic regression and Classification and Regression Tree analysis were used to identify clinical characteristics associated with mortality.

RESULTS

The 461 patients were young (median age, 35 years), male (82%), severely injured (median Injury Severity Score, 33), in shock (median shock index, 1.2; base excess, -9), and transfused a median of 29 U of RBCs, 22 U of fresh frozen plasma (FFP), and 24 U of platelets (PLT). Mortality was 46% at 24 hours and 65% at discharge. Transfusion of RBC/FFP ≥1.5:1 or RBC/PLT ≥1.5:1 was significantly associated with mortality, most pronounced for the 18% of patients who received both RBC/PLT and RBC/FFP ≥1.5:1 (odds ratios, 3.11 and 2.81 for mortality at 24 hours and discharge; both p < 0.01). Classification and Regression Tree identified that age older than 50 years, low initial Glasgow Coma Scale, thrombocytopenia, and resuscitative thoracotomy were associated with low likelihood of survival (14-26%), while absence of these factors was associated with the highest survival (71%).

CONCLUSION

Despite modern massive transfusion protocols, one half of trauma patients receiving UMT are transfused with either RBC/FFP or RBC/PLT in unbalanced ratios ≥1.5:1, with increased associated mortality. Maintaining focus on balanced ratios during UMT is critical, and consideration of advanced age, poor initial mental status, thrombocytopenia, and resuscitative thoracotomy can aid in prognostication.

LEVEL OF EVIDENCE

Prognostic, level III.

Interim analysis of first-in-human phase 1 study to assess safety and efficacy of YBL-006, an anti-PD-1 antibody in advanced solid tumor with exploratory biomarker analysis of tumor mutational burden and artificial intelligence (AI)-powered spatial analysis of tumor-infiltrating lymphocytes

e14552

Background: YBL-006 is an anti-programmed death-1 (PD-1) antibody with a higher affinity compared to that of other PD-1 antibodies, which showed a favorable safety profile in animal models. We designed the first-in-human phase I trial of YBL-006 to assess its safety and efficacy with exploratory biomarker analysis in patients with advanced solid tumors refractory to standard of treatment. Methods: A modified “3+3” design, with the first patient dosed at 0.5 mpk, was followed by conventional dose escalation of 2, 5, and 10 mpk IV. Pharmacokinetics (PK) and pharmacodynamics, including PD-1 receptor occupancy (RO) and serum levels of interferon-gamma (IFN-γ), were assessed. Adverse events (AEs) were graded using the CTCAE v4.03. Tumor response was assessed using the RECIST v1.1 every 8 weeks. For exploratory analysis, tumor mutational burden (TMB) and AI-powered spatial analysis of tumor-infiltrating lymphocyte (TIL) of tumor tissues collected before YBL-006 treatment were performed. The cut-off date for analysis was February 12, 2021. Results: A total of 8 patients enrolled in the 0.5, 2, and 5 mpk cohorts received at least one dose of YBL-006 and median exposure was 15 weeks (ranged 4-26). No dose limiting toxicity occurred and the maximum tolerated dose was not reached until progressing to the 5 mpk. The common treatment-related AEs were G1 fatigue (25%), and G1 hypothyroidism (12.5%). We also observed 1 case of G2 cytokine release syndrome during cycle 1 in 2 mpk which was managed with supportive care alone. No treatment-related deaths have occurred to date. YBL-006 showed a linear PK prolife and both PD-1 RO and serum IFN-γ increased by > 2 times 8 h after the first dose. Tumor evaluation data were available for 7 patients, which showed 1 confirmed complete response (CR, penile squamous cell carcinoma, 2 mpk) and 1 confirmed partial response (PR, anal squamous cell carcinoma, 2 mpk) with durable responses lasting more than 19+ and 10+ weeks respectively, 2 stable disease (SD) and 3 progressive disease (PD). Four tumor samples were available for biomarker analysis. TMBs of patients with CR (8.3/Mb) or PR (9.3/Mb) were higher than those in 2 patients with PD (5.5 and 1.7/Mb). AI-powered spatial analysis of TIL showed that intratumoral TIL density was increased in patients who achieved CR and PR (66.1% and 95.8%, respectively) compared to those in patients who exhibited PD (25.1% and 16.5%, respectively). Conclusions: Interim analysis of phase I study showed that YBL-006 is well tolerated and preliminary biomarker analysis showed that the TMB, and intratumoral TIL infiltration are potentially related to the response to YBL-006. Clinical trial information: NCT04450901.

A first-in-human phase dose-escalation study of YH002, a recombinant humanized agonistic anti-OX40 IgG1 monoclonal antibody, in patients with advanced solid tumors

e14501

Background: YH002 is a recombinant humanized IgG1 antibody that targets the human OX40 receptor. Preclinical studies have demonstrated the specificity, potency, and anti-cancer efficacy of YH002 in a comprehensive panel. The totality of nonclinical data supports progression of YH002 into clinical studies in adult patients (pts) with advanced solid tumors. Methods: This is an ongoing phase 1 dose-escalation study. Patients with advanced or metastatic refractory solid tumors received YH002 as single agent by IV administration at 0.01 to12.0 mg/kg dose levels every 21 days (Q3W), to evaluate the safety, tolerability and preliminary efficacy. An accelerated titration dose escalation design followed by a traditional 3+3 dose algorithm were utilized to assess dose-limiting toxicity (DLT) and identify MTD and/or RP2D. Tumor assessments were performed per RECIST v1.1 every 9 weeks. Results: By December 31 2020, six patients were enrolled and treated at escalating dose levels of 0.01 (n=1), 0.03 (n=1), 0.1 (n=1) and 0.3mg/kg (n=3), with tumor types including colon cancer, thymic cancer, prostate cancer, colorectal cancer, breast cancer and bladder cancer. Median treatment duration was 10.2 weeks (range 2 – 18). The median age of patients was 67 years old (range 47-78). These patients had progressed after a median of 2 prior lines of available standard therapy. As of data cutoff, no dose limiting toxicities (DLTs), no Grade (G) 3 or above adverse events (AE) or AEs leading to treatment discontinuation were reported. Drug-related adverse events (AEs) were all G1/2 events and occurred in 4 patients, including 8 G1 AEs (pneumonitis, rash, pruritus, arthralgia, myalgia, fatigue, lethargy, rash pruritic) and 3 G2 AEs (1 pneumonitis and 2 fatigue). Out of 5 patients having tumor assessment by RECIST, one pt with Thymic SCC at 0.3 mg/kg had best response of stable disease at week 9, one pt with prostate cancer at 0.1 mg/kg experienced Non-CR/Non-PD, and rest of 3 pts experienced progressive disease. Conclusions: These preliminary results demonstrate that YH002 was safe and tolerable up to 0.3mg/kg. Updated safety and antitumor activity will be presented. Clinical trial information: NCT04353102.

Circulating Tumor DNA Reflects Uveal Melanoma Responses to Protein Kinase C Inhibition

Simple Summary

Uveal melanoma (UM) is a rare cancer, with no effective standard systemic therapy in the metastatic setting. Over 95% of UM harbor activating driver mutations that can be detected in the circulation. In this study, circulating tumor DNA (ctDNA) was measured in 17 metastatic UM patients treated with protein kinase C inhibitor (PKCi)-based therapy. ctDNA predicted response to targeted therapy and increasing UM ctDNA preceded radiological progression with a lead-time of 4–10 weeks. Next generation sequencing (NGS) of ctDNA also identified prognostic and treatment resistance mutations. Longitudinal ctDNA monitoring is useful for monitoring disease response and progression in metastatic UM and is a valuable addition to adaptive clinical trial design.

Abstract

The prognosis for patients with UM is poor, and recent clinical trials have failed to prolong overall survival (OS) of these patients. Over 95% of UM harbor activating driver mutations, and this allows for the investigation of ctDNA. In this study, we investigated the value of ctDNA for adaptive clinical trial design in metastatic UM. Longitudinal plasma samples were analyzed for ctDNA in 17 metastatic UM patients treated with PKCi-based therapy in a phase 1 clinical trial setting. Plasma ctDNA was assessed using digital droplet PCR (ddPCR) and a custom melanoma gene panel for targeted next generation sequencing (NGS). Baseline ctDNA strongly correlated with baseline lactate dehydrogenase (LDH) (p < 0.001) and baseline disease burden (p = 0.002). Early during treatment (EDT) ctDNA accurately predicted patients with clinical benefit to PKCi using receiver operator characteristic (ROC) curves (AUC 0.84, [95% confidence interval 0.65–1.0, p = 0.026]). Longitudinal ctDNA assessment was informative for establishing clinical benefit and detecting disease progression with 7/8 (88%) of patients showing a rise in ctDNA and targeted NGS of ctDNA revealed putative resistance mechanisms prior to radiological progression. The inclusion of longitudinal ctDNA monitoring in metastatic UM can advance adaptive clinical trial design.

Feasibility assessment of outpatient colorectal resections at a tertiary referral center

PURPOSE

Enhanced Recovery After Surgery (ERAS) protocols, particularly when paired with advanced laparoscopy, have reduced recovery time following colorectal procedures. The aim of this study was to determine if length of stay (LOS) could be reduced to an overnight observation stay (< 24 h) with comparable perioperative morbidity. The secondary aim was to establish predictive factors contributing to early discharge.

METHODS

This is a retrospective cohort study of all colectomies at a tertiary care center between January 2016 and January 2019. Inclusion criteria included all colorectal resections with varying surgical approaches. Patients underwent a standardized ERAS protocol. A logistical regression model was conducted for predictive factors.

RESULTS

Three hundred sixty patients were included (55.3% female). Of these, 78 (21.7%) patients were discharged within < 24 h and 112 (31.1%) were discharged within 24-48 h. The remainder comprised the > 48 h group. Age differed significantly between the < 24 h and 24-48 h groups (p < 0.0001). Patients discharged within 24 h were younger (59.4 ± 12.3 years), had a lower CCI score (3.1; p = 0.0026), and lower ASA class (p < 0.0001). Emergency department visits (p = 0.3329) and readmissions (p = 0.6453) prior to POD 30 remained comparable among all groups. Younger age, low ASA, and minimally invasive surgical approach all contributed to ultra-fast discharge.

CONCLUSION

ERAS protocols may allow for discharge within 24 h following a major colorectal resection, all with low perioperative morbidity and mortality. The predictive factors for discharge within 24 h include a low ASA (I or II), and a minimally invasive surgical approach.

Immunomodulatory lipid mediator profiling of cerebrospinal fluid following surgery in older adults

Arachidonic acid (AA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) derived lipids play key roles in initiating and resolving inflammation. Neuro-inflammation is thought to play a causal role in perioperative neurocognitive disorders, yet the role of these lipids in the human central nervous system in such disorders is unclear. Here we used liquid chromatography–mass spectrometry to quantify AA, DHA, and EPA derived lipid levels in non-centrifuged cerebrospinal fluid (CSF), centrifuged CSF pellets, and centrifuged CSF supernatants of older adults obtained before, 24 h and 6 weeks after surgery. GAGE analysis was used to determine AA, DHA and EPA metabolite pathway changes over time. Lipid mediators derived from AA, DHA and EPA were detected in all sample types. Postoperative lipid mediator changes were not significant in non-centrifuged CSF (p > 0.05 for all three pathways). The AA metabolite pathway showed significant changes in centrifuged CSF pellets and supernatants from before to 24 h after surgery (p = 0.0000247, p = 0.0155 respectively), from before to 6 weeks after surgery (p = 0.0000497, p = 0.0155, respectively), and from 24 h to 6 weeks after surgery (p = 0.0000499, p = 0.00363, respectively). These findings indicate that AA, DHA, and EPA derived lipids are detectable in human CSF, and the AA metabolite pathway shows postoperative changes in centrifuged CSF pellets and supernatants.

Enhanced Recovery After Surgery Protocols. Does Frailty Play a Role?

INTRODUCTION

The 5-modified frailty index (mFI) is a valid predictor of 30-day mortality after surgery. With the wide implementation of enhanced recovery after surgery (ERAS) protocols in colorectal patients, the predictive power of frailty and its contribution to morbidity and length of stay (LOS) can be underestimated.

METHODS

We reviewed all colectomy patients undergoing ERAS protocol at a single, tertiary care institution from January 2016-January 2019. The 5-mFI score was calculated based on the presence of 5 comorbidities: Congestive heart failure (CHF), diabetes mellitus, chronic obstructive pulmonary disease, functional status, and hypertension (HTN). Multivariate analysis was used to assess the impact of 5-mFI score on morbidity, emergency department (ED) visits, readmissions, and LOS.

RESULTS

360 patients were evaluated including 163 elderly patients. Frailer patients had a higher rate of ED visits (P = .024), readmissions (P = .029), and LOS (P < .001). Patients with CHF had a higher chance of prolonged LOS, whereas patients with HTN had a higher chance of ED. Elderly patients with an mFI score of 3 and 4 were likely to have longer LOS (P = .01, P = .07, respectively). Elderly patients with an mFI score of 4 were 15 times more likely to visit ED and 22 times more likely to be readmitted than patients with an mFI score of 0.

DISCUSSION

An increase in 5-mFI for elderly patients undergoing colorectal procedures increases ED visits or readmissions, and it correlates to a higher LOS, especially in elderly patients. This instrument should be used in the assessment of frail, elderly patients undergoing colorectal procedures.

Protocol-Based Intravenous Fluid Hydration for Newly Created Ileostomies Decreases Readmissions Secondary to Dehydration

BACKGROUND

Newly created ileostomies often result in patient readmission due to dehydration secondary to high ostomy output. Implementation of a mandatory home intravenous hydration protocol can avoid this. We aim to evaluate the impact of mandatory home intravenous hydration for patients with newly created ileostomies.

MATERIALS AND METHODS

All patients at a single, tertiary care center who underwent ileostomy creation during a period of sporadic home intravenous hydration (February 2011-December 2013) and mandatory protocol hydration (March 2016-December 2018) were reviewed for incidence of dehydration, readmissions, and emergency department visits.

RESULTS

241 patients were evaluated. 119 were in the "sporadic" group and 122 were in the "protocol" group. Operative approach differed among both groups, with hydration protocol patients undergoing 15% less open procedures and 4.9% more hand-assisted laparoscopic procedures (P = .0017). Prior to protocol implementation, 23.5% of patients were sent home with intravenous hydration. Length of hospital stay after index ileostomy creation was shorter for "protocol" patients by 3.3 days (P < .0001). 15.1% of "sporadic" patients experienced dehydration as compared to 7.4% of "protocol" patients (P = .0283). Following protocol implementation, the number of patients readmitted due to dehydration increased from 13 to 14 (P = .01).

DISCUSSION

Standardized, mandatory at-home intravenous hydration following ileostomy creation leads to a significant reduction in postoperative incidence of dehydration and dehydration-associated readmissions. This protocol should be followed for all patients with newly created ileostomies, so long as adequate home health nursing support and active surveillance are available.

Findings on Colonoscopy after Diverticulitis: A Multicenter Review

Diverticular disease is a common problem where patients with diverticulosis have a 1–4 per cent risk of acute diverticulitis. Current guidelines recommend a colonoscopy after.the resolution of acute diverticulitis. The aim of this study was to evaluate the yield of significant findings on colonoscopy after an episode of diverticulitis. This is a retrospective analysis of patients who underwent colonoscopy after an episode of diverticulitis between November 2005 and August 2017 at three major teaching hospitals. Advanced adenomas were defined as adenomas ≥1 cm, serrated adenomas, and tubulovillous or villous adenomas. A total of 584 patients (298 males; 51%) underwent colonoscopy for a history of diverticulitis after resolution of acute symptoms. Colonoscopy was complete in 488 patients (84%). Among these 488 patients, 446 had diverticular disease, 31 had advanced adenomas, and four had adenocarcinomas. Colonoscopies were incomplete in 96 patients (16%). Forty-six of those patients underwent surgery. The overall incidence of advanced adenomas and adenocarcinomas was 32 (5.4%) and nine (1.5%), respectively. In our study, the prevalence of advanced adenomas and adenocarcinomas was relatively high compared with the average risk individuals. Our findings support that patients after an episode of diverticulitis should continue to get a colonoscopy.

Circulating tumor DNA (ctDNA) in patients (pts) with metastatic uveal melanoma (UM) treated with protein kinase C inhibitor (PKCi)

e22054

Background: UM is the most common primary intraocular malignancy. About 50% of pts with UM will develop metastatic disease and currently there is no effective treatment in metastatic UM. Nearly 95% of UM harbour mutually exclusive activating mutations in GNAQ, GNA11, CYSTLR2 and PLCb4. We sought to evaluate ctDNA in metastatic UM pts receiving experimental early phase clinical trial of LXS196, a PKCi, using digital droplet PCR (ddPCR) and targeted ion torrent next generation sequencing (NGS). Methods: 17 pts with metastatic UM were identified from a single institution. Pt characteristics including mutation status, disease volume using sum of product of disease (SPOD), best response and clinical benefit defined as partial response (PR) or stable disease (SD) > 6 months were assessed. Plasma samples at baseline and early on treatment (EOT) (14 – 30 days on treatment) were analysed for ctDNA using mutation specific ddPCR. A custom made NGS panel covering 95% of UM mutations was used on plasma ctDNA samples at baseline and on treatment. The allele frequency (AF) of activating mutations identified using ion torrent NGS analysis were then validated using ddPCR. Results: Using ddPCR, 16/17 pts had a +ve ctDNA at baseline with baseline ctDNA copies correlating with LDH (n = 17, p = < 0.001, Spearman’s rank r = 0.8015) and SPOD (n = 17, p = 0.005, r = 0.6642). 16/17 pts had paired samples at baseline and EOT and only 4/16 pts were undetectable at EOT. These 4 pts were GNA11 Q209L positive, had below median SPOD (median 5986, range 200 – 16782), and low numbers of liver metastases (median 9, range 1 – 49). Of these 4 pts, one had PR and three had SD (two with SD > 6 months) as best response. A further 8 pts had +ve ctDNA at baseline and showed a reduction in EOT (reduction range 46 – 99%). Of these 8 pts, one had PR, four had SD (two with SD > 6 months) and three had progressive disease (PD) as best response. The remaining 4 pts showed increasing ctDNA from baseline to EOT and all had SD/PD. Using ROC analysis, EOT ctDNA predicted clinical benefit to PKCi (AUC 0.84, [95% confidence interval, 0.65-1.0, p = 0.026]). AF of ion torrent NGS correlated significantly with ddPCR AF (n = 30, p = < 0.001, r = 0.968). Ion torrent NGS was able to detect additional mutations implicated in UM prognosis including SF3B1 mutations in 4 pts. Conclusions: Baseline ctDNA correlates with baseline LDH level and disease volume. EOT ctDNA predicted clinical benefit to PKCi. The ctDNA AF derived from ddPCR and NGS was comparable and targeted ion torrent NGS was useful in detecting driver as well as additional mutations in UM.

Whole genome landscapes of uveal melanoma show an ultraviolet radiation signature in iris tumours

Uveal melanoma (UM) is the most common intraocular tumour in adults and despite surgical or radiation treatment of primary tumours, ~50% of patients progress to metastatic disease. Therapeutic options for metastatic UM are limited, with clinical trials having little impact. Here we perform whole-genome sequencing (WGS) of 103 UM from all sites of the uveal tract (choroid, ciliary body, iris). While most UM have low tumour mutation burden (TMB), two subsets with high TMB are seen; one driven by germline MBD4 mutation, and another by ultraviolet radiation (UVR) exposure, which is restricted to iris UM. All but one tumour have a known UM driver gene mutation (GNAQ, GNA11, BAP1, PLCB4, CYSLTR2, SF3B1, EIF1AX). We identify three other significantly mutated genes (TP53, RPL5 and CENPE).

Uveal melanoma has a propensity to metastasise. Here, the authors report the whole genome sequence of 103 uveal melanomas and find that the tumour mutational burden is variable and that two subsets of tumours are characterised by MBD4 mutations and a UV exposure signature.

The Impact of Nonsteroidal Anti-Inflammatory Drugs, Beta Blockers, and Metformin on the Efficacy of Anti-PD-1 Therapy in Advanced Melanoma

Anti-programmed cell death protein-1 (anti-PD-1) therapy has greatly improved outcomes of patients with melanoma; however, many fail to respond. Although preclinical studies suggest a potentially synergistic relationship with anti-PD-1 therapy and certain concurrent medications, their clinical role remains unclear. Here, we retrospectively evaluated the use of nonsteroidal anti-inflammatory drugs (NSAIDs) and other drugs in 330 patients with melanoma treated with anti-PD-1 therapy from four academic centers. In the cohort, 37% of patients used NSAIDs including aspirin (acetylsalicylic acid; ASA; 47%), cyclooxygenase (COX)-2 inhibitors (2%), and non-ASA/nonselective COX inhibitor NSAIDs (59%). The objective response rates (ORRs) were similar in patients with NSAID (43.4%) and no NSAID (41.3%) use with no significant difference in overall suvival (OS). There was a trend toward improved progression-free survival (PFS) in patients who took NSAIDs (median PFS: 8.5 vs. 5.2 months; p = .054). Most patients (71.3%) took NSAIDs once daily or as needed. Multivariate analysis did not reveal an association with NSAID use with ORR, PFS, or OS. Concurrent use of metformin or beta blockers did not affect ORR, PFS, or OS. Our study found no conclusive association of concurrent NSAID or other medication use with improved outcomes in patients with melanoma treated with anti-PD-1 therapy. Larger and more systematic analysis is required to confirm these findings.

P785 Left ventricular geometry and myocardial contractility modulate impact of statins on prognosis in patients with acute heart failure

Funding Acknowledgements

N/A

Background/Introduction: The benefit of statins in patients with heart failure (HF) remains controversial and the mechanism of action is largely speculative. We investigated whether survival benefit with statins differs according to left ventricular (LV) geometry and myocardial contractility in acute HF patients.

Methods

We enrolled 1792 acute HF patients receiving statins and 2296 patients not receiving statins admitted from 2009 to 2016. The LV and right ventricular (RV) global longitudinal strain (GLS) was assessed as a measure of myocardial contractility. Patients were classified into 2 groups based on ischemic etiology of HF and further divided into 4 subgroups according to the median values of LV-GLS or RV-GLS. The primary outcome was 5-year all-cause mortality. The study protocol was approved by the ethics committee at each institute and complied with the Declaration of Helsinki. The need for written informed consent was waived.

Results

During the 5-year follow-up, 1740 (40.4%) patients died and they had more unfavorable baseline characteristics. Statin therapy was significantly associated with improved survival in overall patients and in both groups with and without ischemic etiology (all p &lt;0.001). Patients with concentric remodeling/hypertrophy and eccentric hypertrophy demonstrated survival benefit with statin therapy (P = 0.033, 0.004, and 0.008, respectively), while those with normal geometry did not (p = 0.123). In the non-ischemic HF group, survival benefit with statin therapy was confined to patients with low LV-GLS (p = 0.045) or those with low RV-GLS p = 0.003). On the contrary, in ischemic HF group, survival benefit with statin therapy was observed in all patients regardless of the values of LV-GLS or RV-GLS. Significant interactions were present between statin use and diabetes mellitus and IHD (p for interaction = 0.027 and 0.003, respectively) regarding mortality.

Conclusions

LV geometry and myocardial contractility may modulate the effects of statins in patients with acute HF. These echocardiographic measures can provide prognostic information to guide tailored statin treatment in this population. Our findings may also help to develop more well-designed prospective studies, in terms of a more homogenous study population, to confirm survival benefit with statin therapy.

Abstract P785 Figure. Multivariate Cox survival curves

Findings on Colonoscopy after Diverticulitis: A Multicenter Review

Diverticular disease is a common problem where patients with diverticulosis have a 1-4 per cent risk of acute diverticulitis. Current guidelines recommend a colonoscopy after.the resolution of acute diverticulitis. The aim of this study was to evaluate the yield of significant findings on colonoscopy after an episode of diverticulitis. This is a retrospective analysis of patients who underwent colonoscopy after an episode of diverticulitis between November 2005 and August 2017 at three major teaching hospitals. Advanced adenomas were defined as adenomas ≥1 cm, serrated adenomas, and tubulovillous or villous adenomas. A total of 584 patients (298 males; 51%) underwent colonoscopy for a history of diverticulitis after resolution of acute symptoms. Colonoscopy was complete in 488 patients (84%). Among these 488 patients, 446 had diverticular disease, 31 had advanced adenomas, and four had adenocarcinomas. Colonoscopies were incomplete in 96 patients (16%). Forty-six of those patients underwent surgery. The overall incidence of advanced adenomas and adenocarcinomas was 32 (5.4%) and nine (1.5%), respectively. In our study, the prevalence of advanced adenomas and adenocarcinomas was relatively high compared with the average risk individuals. Our findings support that patients after an episode of diverticulitis should continue to get a colonoscopy.

Medicaid And Private Insurance Coverage For Low-Income Asian Americans, Native Hawaiians, And Pacific Islanders, 2010-16

To determine how low-income Asian American, Native Hawaiian, and Pacific Islander (AANHPI) adults gained health insurance coverage-specifically, via Medicaid or private insurance-under the Affordable Care Act, we used a difference-in-differences approach to compare uninsurance rates in 2010-13 and 2015-16. In Medicaid expansion states, adjusted Medicaid coverage gains were 9.67 percentage points larger than in nonexpansion states; however, adjusted private coverage gains in expansion states were 10.19 percentage points lower. These results indicate that, in contrast to the case for other racial/ethnic groups, for AANHPI the Medicaid coverage increases in expansion states were of similar magnitude to the private insurance coverage increases in nonexpansion states. Reasons for this may include differences in willingness to enroll in public versus private coverage, barriers related to language or citizenship status, or other factors. Future studies are needed to understand these patterns and promote health equity for this population.

A Novel Collateral Imaging Method Derived from Time-Resolved Dynamic Contrast-Enhanced MR Angiography in Acute Ischemic Stroke: A Pilot Study

BACKGROUND AND PURPOSE

Assessment of the collateral status has been emphasized for appropriate treatment decisions in patients with acute ischemic stroke. The purpose of this study was to introduce a multiphase MRA collateral imaging method (collateral map) derived from time-resolved dynamic contrast-enhanced MRA and to verify the value of the multiphase MRA collateral map in acute ischemic stroke by comparing it with the multiphase collateral imaging method (MRP collateral map) derived from dynamic susceptibility contrast-enhanced MR perfusion.

MATERIALS AND METHODS

From a prospectively maintained registry of acute ischemic stroke, MR imaging data of patients with acute ischemic stroke caused by steno-occlusive lesions of the unilateral ICA and/or the M1 segment of the MCA were analyzed. We generated collateral maps using dynamic signals from dynamic contrast-enhanced MRA and DSC-MRP using a Matlab-based in-house program and graded the collateral scores of the multiphase MRA collateral map and the MRP collateral map independently. Interobserver reliabilities and intermethod agreement between both collateral maps for collateral grading were tested.

RESULTS

Seventy-one paired multiphase MRA and MRP collateral maps from 67 patients were analyzed. The interobserver reliabilities for collateral grading using multiphase MRA or MRP collateral maps were excellent (weighted κ = 0.964 and 0.956, respectively). The agreement between both collateral maps was also excellent (weighted κ = 0.884; 95% confidence interval, 0.819-0.949).

CONCLUSIONS

We demonstrated that the dynamic signals of dynamic contrast-enhanced MRA could be used to generate multiphase collateral images and showed the possibility of the multiphase MRA collateral map as a useful collateral imaging method in acute ischemic stroke.

Clinical models to predict response and survival in metastatic melanoma (MM) patients (pts) treated with anti-PD-1 alone (PD1) or combined with ipilimumab (IPI+PD1)

9542

Background: Currently there are no robust biomarkers to predict immunotherapy response in MM. Specific clinical and molecular variables have been proposed, but in most cases, these factors have been studied individually. We sought to build a predictive model for response rate (RR), progression-free survival (PFS) and overall survival (OS), by including clinical data available at the point of treatment selection for MM pts treated with PD1 or IPI+PD1. Methods: 786 MM pts were included in 4 cohorts; 447 pts treated with PD1 (discovery, n = 343; validation, n = 104) and 339 pts treated with IPI+PD1 (discovery, n = 229; validation, n = 110). Demographics, disease characteristics and baseline blood parameters were examined. Predictive models were selected using multivariate Cox proportional hazard model, logistic regression and LASSO. ROC curve analyses were performed for each model and validation was measured by discrimination índex (c-statistic). Results: Predictive models for RR and PFS in PD1 pts (AUC = 0.69 and AUC = 0.71, respectively) included mutational status (HR for PFS: BRAF 1; NRAS 0.68; WT 0.57; P = 0.002), primary melanoma site (HR for PFS: occult 1; head and neck 0.67, others 1.04; P = 0.052), elevated LDH (HR for PFS: 1.77, P < 0.0001) and monocyte count > median (HR for PFS: 1.56, P = 0.003). Predictive models for RR and PFS in IPI+PD1 treated pts (AUC = 0.71 and AUC = 0.73, respectively) included AJCC stage M1C/M1D (HR for PFS: 2.12, P = 0.009), elevated LDH (HR for PFS: 2.65, P < 0.0001), liver mets (HR for PFS: 1.63, P = 0.038) and basophil count > median (HR for PFS: 0.50, P = 0.003). ECOG ≥ 1, elevated LDH and brain mets associated with worse OS and were included in predictive models for OS in PD1 (AUC = 0.74) and IPI+PD1 (AUC = 0.85). These models showed consistency with internal and external validation (c-statistic: < 10% difference between the original model and validations for all outcomes). Conclusions: A combination of routinely collected clinical factors are highly predictive of outcome in MM pts treated with PD1 and IPI+PD1. A prognostic index will be presented for each treatment. Such tools may be practical, cheap and valuable for clinical decision making.

Yttrium-90 Radioembolization After Local Hepatic Therapy: How Prior Treatments Impact Patient Selection, Dosing, and Toxicity

Numerous local treatment strategies now exist for patients with primary and metastatic liver tumors. Increasingly, patients who cannot be adequately treated with a single form of focal therapy, go on to receive a variety of sequential treatments. However, the impact of each prior therapy on subsequent treatments and the cumulative toxicity of these therapies remains uncertain. Yttrium-90 radioembolization is becoming an increasingly common treatment for patients with hepatic malignancies. Though the baseline toxicity of radioembolization is low, greater care must be taken when treating patients who have undergone prior hepatic treatments. While this population can be treated safely, additional measures should be taken to ensure that patients are carefully screened and all effort is made to minimize liver toxicity.

Rectal Cancer Complete Response Outcomes in a Community-Based Hospital Comparable with Large Cancer Centers When Multidisciplinary Approach to Rectal Cancer is Used

Achievement of pathologic complete response (pCR) in patients with locally advanced rectal cancer correlates with improved prognosis relative to non-pCR counterparts. Such correlations are not well established in the context of a community-based hospital. This study aims to examine pCR rates, recurrences, and survival data for locally advanced rectal cancer patients in community settings. A single-center retrospective chart review was performed at a community-based hospital. Study population consisted of 119 patients with locally advanced rectal cancer treated with neo-adjuvant chemoradiotherapy, followed by surgical resection. Patients with a history of metastasis, inflammatory bowel disease, hereditary cancer syndromes, concurrent or prior malignancy, and emergent surgery were excluded. Twenty-four patients (20.2%) achieved pCR. Across both groups, all demographics and perioperative characteristics were comparable. The five-year survival was 73.7 per cent in the non-pCR group and 95.8 per cent in the pCR group ( P = 0.0243). At five years, 27.7 per cent of the non-pCR group had a recurrence, as compared with none in the pCR group ( P = 0.0018). Based on our study, we believe that a multidisciplinary approach to rectal cancer used at a community-based hospital can achieve oncological outcomes and survival benefits similar to those of larger academic tertiary care institutions.

Rectal Cancer Complete Response Outcomes in a Community-Based Hospital Comparable with Large Cancer Centers When Multidisciplinary Approach to Rectal Cancer Is Used

Achievement of pathologic complete response (pCR) in patients with locally advanced rectal cancer correlates with improved prognosis relative to non-pCR counterparts. Such correlations are not well established in the context of a community-based hospital. This study aims to examine pCR rates, recurrences, and survival data for locally advanced rectal cancer patients in community settings. A single-center retrospective chart review was performed at a community-based hospital. Study population consisted of 119 patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy, followed by surgical resection. Patients with a history of metastasis, inflammatory bowel disease, hereditary cancer syndromes, concurrent or prior malignancy, and emergent surgery were excluded. Twenty-four patients (20.2%) achieved pCR. Across both groups, all demographics and perioperative characteristics were comparable. The five-year survival was 73.7 per cent in the non-pCR group and 95.8 per cent in the pCR group (P = 0.0243). At five years, 27.7 per cent of the non-pCR group had a recurrence, as compared with none in the pCR group (P = 0.0018). Based on our study, we believe that a multidisciplinary approach to rectal cancer used at a community-based hospital can achieve oncological outcomes and survival benefits similar to those of larger academic tertiary care institutions.

Systematic review of evidence on public health in the Democratic People's Republic of Korea

Background

Engaging in public health activities in the Democratic People’s Republic of Korea (DPRK, also known as North Korea) offers a means to improve population health for its citizens and the wider region. Such an engagement requires an understanding of current and future needs.

Methods

We conducted a systematic search of five English and eight Korean language databases to identify available literature published between 1988 and 2017. A narrative review of evidence was conducted for five major categories (health systems, communicable diseases (CDs), non-communicable diseases (NCDs), injuries, and reproductive, maternal, newborn and child health (RMNCH) and nutrition).

Findings

We found 465 publications on the DPRK and public health. Of the 253 articles that addressed major disease categories, we found under-representation of publications relative to proportion of disease burden for the two most significant causes: NCDs (54.5% publications vs 72.6% disability adjusted life years (DALYs)) and injuries (0.4% publications vs 12.1% DALYs), in comparison to publications on the third and fourth largest disease burdens, RMNCH and nutrition (30.4% publications vs 8.6% DALYs) and CDs (14.6% publications vs 6.7% DALYs) which were over-represented. Although most disease category articles were on NCDs, the majority of NCD articles addressed mental health of refugees. Only 165 articles addressed populations within the DPRK and among these, we found publication gaps on social and environmental determinants of health, CDs, and NCDs.

Conclusion

There are gaps in the public health literature on the DPRK. Future research should focus on under-studied, significant burdens of disease. Moreover, establishing more precise estimates of disease burden and their distribution, as well as analysis on health systems responses aimed at addressing them, can result in improvements in population health.