Decreases in Blood Pressure During Thrombectomy Are Associated With Larger Infarct Volumes and Worse Functional Outcome

Background and Purpose- After large-vessel intracranial occlusion, the fate of the ischemic penumbra, and ultimately final infarct volume, largely depends on tissue perfusion. In this study, we evaluated whether blood pressure reduction and sustained relative hypotension during endovascular thrombectomy are associated with infarct progression and functional outcome. Methods- We identified consecutive patients with large-vessel intracranial occlusion ischemic stroke who underwent mechanical thrombectomy at 2 comprehensive stroke centers. Intraprocedural mean arterial pressure (MAP) was monitored throughout the procedure. ΔMAP was calculated as the difference between admission MAP and lowest MAP during endovascular thrombectomy until recanalization. Sustained hypotension was measured as the area between admission MAP and continuous measurements of intraprocedural MAP (aMAP). Final infarct volume was measured using magnetic resonance imaging at 24 hours, and functional outcome was assessed using the modified Rankin Scale at discharge and 90 days. Associations with outcome were analyzed using linear and ordinal multivariable logistic regression. Results- Three hundred ninety patients (mean age 71±14 years, mean National Institutes of Health Stroke Scale score of 17) were included in the study; of these, 280 (72%) achieved Thrombolysis in Cerebral Infarction 2B/3 reperfusion. Eighty-seven percent of patients experienced MAP reductions during endovascular thrombectomy (mean 31±20 mm Hg). ΔMAP was associated with greater infarct growth ( P=0.036) and final infarct volume ( P=0.035). Mean ΔMAP among patients with favorable outcomes (modified Rankin Scale score, 0-2) was 20±21 mm Hg compared with 30±24 mm Hg among patients with poor outcome ( P=0.002). In the multivariable analysis, ΔMAP was independently associated with higher (worse) modified Rankin Scale scores at discharge (adjusted odds ratio per 10 mm Hg, 1.17; 95% CI, 1.04-1.32; P=0.009) and at 90 days (adjusted odds ratio per 10 mm Hg, 1.22; 95% CI, 1.07-1.38; P=0.003). The association between aMAP and outcome was also significant at discharge ( P=0.002) and 90 days ( P=0.001). Conclusions- Blood pressure reduction before recanalization is associated with larger infarct volumes and worse functional outcomes for patients affected by large-vessel intracranial occlusion stroke. These results underscore the importance of BP management during endovascular thrombectomy and highlight the need for further investigation of blood pressure management after large-vessel intracranial occlusion stroke.

Advances in Acute Myeloid Leukemia: Recently Approved Therapies and Drugs in Development

Acute myeloid leukemia (AML) is a genetically heterogeneous malignancy comprised of various cytogenetic and molecular abnormalities that has notoriously been difficult to treat with an overall poor prognosis. For decades, treatment options were limited to either intensive chemotherapy with anthracycline and cytarabine-based regimens (7 + 3) or lower intensity regimens including hypomethylating agents or low dose cytarabine, followed by either allogeneic stem cell transplant or consolidation chemotherapy. Fortunately, with the influx of rapidly evolving molecular technologies and new genetic understanding, the treatment landscape for AML has dramatically changed. Advances in the formulation and delivery of 7 + 3 with liposomal cytarabine and daunorubicin (Vyxeos) have improved overall survival in secondary AML. Increased understanding of the genetic underpinnings of AML has led to targeting actionable mutations such as FLT3, IDH1/2 and TP53, and BCL2 or hedgehog pathways in more frail populations. Antibody drug conjugates have resurfaced in the AML landscape and there have been numerous advances utilizing immunotherapies including immune checkpoint inhibitors, antibody-drug conjugates, bispecific T cell engager antibodies, chimeric antigen receptor (CAR)-T therapy and the development of AML vaccines. While there are dozens of ongoing studies and new drugs in the pipeline, this paper serves as a review of the advances achieved in the treatment of AML in the last several years and the most promising future avenues of advancement.

Copy number signatures predict chromothripsis and clinical outcomes in newly diagnosed multiple myeloma

Chromothripsis is detectable in 20–30% of newly diagnosed multiple myeloma (NDMM) patients and is emerging as a new independent adverse prognostic factor. In this study we interrogate 752 NDMM patients using whole genome sequencing (WGS) to investigate the relationship of copy number (CN) signatures to chromothripsis and show they are highly associated. CN signatures are highly predictive of the presence of chromothripsis (AUC = 0.90) and can be used identify its adverse prognostic impact. The ability of CN signatures to predict the presence of chromothripsis is confirmed in a validation series of WGS comprised of 235 hematological cancers (AUC = 0.97) and an independent series of 34 NDMM (AUC = 0.87). We show that CN signatures can also be derived from whole exome data (WES) and using 677 cases from the same series of NDMM, we are able to predict both the presence of chromothripsis (AUC = 0.82) and its adverse prognostic impact. CN signatures constitute a flexible tool to identify the presence of chromothripsis and is applicable to WES and WGS data.

Chromothripsis is associated with unfavourable outcomes in multiple myeloma (MM), but its detection usually requires whole genome sequencing. Here the authors develop an approach to detect chromothripsis in MM based on copy-number signatures that also works with whole exome sequencing data.

Lesinurad: what the nephrologist should know

Lesinurad is an oral inhibitor of the monocarboxylic/urate transporter URAT1 encoded by the SLC22A12 gene. Market authorization was granted in February 2016 in Europe and December 2015 in the USA. As a potentially nephrotoxic uricosuric drug acting on the kidney, nephrologists should become familiar with its indications and safety profile. The approved indication is treatment of gout in combination with a xanthine oxidase (XO) inhibitor in adult patients who have not achieved target serum uric acid levels with an XO inhibitor alone. It is not indicated for asymptomatic hyperuricaemia or for patients with estimated creatinine clearance <45 mL/min. The only authorized daily dose is 200 mg and cannot be exceeded because of the nephrotoxicity risk. Nephrotoxicity is thought to be related to uricosuria. At the 200 mg/day dose, serum creatinine more than doubled in 1.8% of lesinurad patients (versus 0% in placebo) and in 11% of these it was not reversible. In addition, it is subject to a risk management plan given the potential association with cardiovascular events. In randomized clinical trials, the association of lesinurad with either allopurinol or febuxostat achieved a greater reduction in serum uric acid (∼1 mg/dL lower) than the XO inhibitors alone, and this allowed the serum uric acid target to be met in a higher proportion of patients, which was the primary endpoint. However, no clinical differences were observed in gout flares or tophi, although these were not the primary endpoints.

Genomic Profiling Reveals Germline Predisposition and Homologous Recombination Deficiency in Pancreatic Acinar Cell Carcinoma

PURPOSE

To determine the genetic predisposition underlying pancreatic acinar cell carcinoma (PACC) and characterize its genomic features.

METHODS

Both somatic and germline analyses were performed using an Food and Drug Administration-authorized matched tumor/normal sequencing assay on a clinical cohort of 28,780 patients with cancer, 49 of whom were diagnosed with PACC. For a subset of PACCs, whole-genome sequencing (WGS; n = 12) and RNA sequencing (n = 6) were performed.

RESULTS

Eighteen of 49 (36.7%) PACCs harbored germline pathogenic variants in homologous recombination (HR) and DNA damage response (DDR) genes, including BRCA1 (n = 1), BRCA2 (n = 12), PALB2 (n = 2), ATM (n = 2), and CHEK2 (n = 1). Thirty-one PACCs displayed pure, and 18 PACCs harbored mixed acinar cell histology. Fifteen of 31 (48%) pure PACCs harbored a germline pathogenic variant affecting HR-/DDR-related genes. BRCA2 germline pathogenic variants (11 of 31, 35%) were significantly more frequent in pure PACCs than in pancreatic adenocarcinoma (86 of 2,739, 3.1%; P < .001), high-grade serous ovarian carcinoma (67 of 1,318, 5.1%; P < .001), prostate cancer (116 of 3,401, 3.4%; P < .001), and breast cancer (79 of 3,196, 2.5%; P < .001). Genomic features of HR deficiency (HRD) were detected in 7 of 12 PACCs undergoing WGS, including 100% (n = 6) of PACCs with germline HR-related pathogenic mutations and 1 of 6 PACCs lacking known pathogenic alterations in HR-related genes. Exploratory analyses revealed that in PACCs, the repertoire of somatic driver genetic alterations and the load of neoantigens with high binding affinity varied according to the presence of germline pathogenic alterations affecting HR-/DDR-related genes and/or HRD.

CONCLUSION

In a large pan-cancer cohort, PACC was identified as the cancer type with the highest prevalence of both BRCA2 germline pathogenic variants and genomic features of HRD, suggesting that PACC should be considered as part of the spectrum of BRCA-related malignancies.

Routine Evaluation of Minimal Residual Disease in Myeloma Using Next-Generation Sequencing Clonality Testing: Feasibility, Challenges, and Direct Comparison with High-Sensitivity Flow Cytometry

The 2016 International Myeloma Working Group consensus recommendations emphasize high-sensitivity methods for minimal residual disease (MRD) detection, treatment response assessment, and prognostication. Next-generation sequencing (NGS) of IGH gene rearrangements is highly specific and sensitive, but its description in routine clinical practice and performance comparison with high-sensitivity flow cytometry (hsFC) remain limited. In this large, single-institution study including 438 samples from 251 patients, the use of NGS targeting the IGH and IGK genes for clonal characterization and monitoring, with comparison to hsFC, is described. The index clone characterization success rate was 93.6% (235/251), which depended on plasma cell (PC) cellularity, reaching 98% when PC ≥10% and below 80% when PC <5%. A total of 85% of cases were successfully characterized using leader and FR1 primer sets, and most clones showed high somatic hypermutation rates (median, 8.1%). Among monitoring samples from 124 patients, 78.6% (147/187) had detectable disease by NGS. Concordance with hsFC was 92.9% (170/183). Discordant cases encompassed 8 of 124 hsFC MRD+/NGS MRD− patients (6.5%) and 4 of 124 hsFC MRD−/NGS MRD+ patients (3.2%), all with low-level disease near detection limits for both assays. Among concordant hsFC MRD−/NGS MRD− cases, only 5 of 24 patients (20.8%) showed subsequent overt relapse at 3-year follow-up. HsFC and NGS showed similar operational sensitivity, and the choice of test may depend on practical, rather than test performance, considerations.

Cardiovascular mortality among chronic myeloid leukemia patients in the pre-tyrosine kinase inhibitor (TKI) and TKI eras: a surveillance, epidemiology and end results (SEER) analysis

Despite remarkable efficacy, there is an emerging concern regarding TKI-associated cardiovascular toxicity in CML. Long term follow-up studies on association between TKI therapy and cardiovascular outcome have been limited. CML patients were accessed from the SEER 18 database from 1992 to 2011. Cardiovascular disease (CVD) specific mortality was calculated comparing the pre-TKI era to the TKI era using the Fine-Gray competing risk model. Overall, the TKI era was associated with a reduced cardiovascular mortality compared with the pre-TKI era (HR = 0.72; 95%CI, 0.59-0.89). Our results argue for continued aggressive screening, identification and management of cardiovascular risk factors among all CML patients, especially the elderly, and further investigation into specific mechanisms, factors and predictors of risks in TKI-treated CML.

Pancreatic ductal adenocarcinoma in the era of precision medicine

The paradigm for treatment of PDAC is shifting from a "one size fits all" of cytotoxic therapy to a precision medicine approach based on specific predictive biomarkers for a subset of patients. As the genomic landscape of pancreatic carcinogenesis has become increasingly defined, several oncogenic alterations have emerged as actionable targets and their use has been validated in novel approaches such as targeting mutated germline DNA damage response genes (BRCA) and mismatch deficiency (dMMR/MSI-H) or blockade of rare somatic oncogenic fusions. Chemotherapy selection based on transcriptomic subtypes and developing stroma- and immune-modulating strategies have yielded encouraging results and may open therapeutic refinement to a broader PDAC population. Notwithstanding, a series of negative late-stage trials over the last year continue to underscore the inherent challenges in the treatment of PDAC. Multifactorial therapy resistance warrants further exploration in PDAC "omics" and tumor-stroma-immune cells crosstalk. Herein, we discuss precision medicine approaches applied to the treatment of PDAC, its current state and future perspective.

Methylation Analyses Reveal Promoter Hypermethylation as a Rare Cause of "Second Hit" in Germline BRCA1-Associated Pancreatic Ductal Adenocarcinoma

BACKGROUND AND OBJECTIVE

Pancreatic ductal adenocarcinoma (PDAC) is characterized by the occurrence of pathogenic variants in BRCA1/2 in 5-6% of patients. Biallelic loss of BRCA1/2 enriches for response to platinum agents and poly (ADP-ribose) polymerase 1 inhibitors. There is a dearth of evidence on the mechanism of inactivation of the wild-type BRCA1 allele in PDAC tumors with a germline BRCA1 (gBRCA1) pathogenic or likely pathogenic variant (P/LPV). Herein, we examine promotor hypermethylation as a "second hit" mechanism in patients with gBRCA1-PDAC.

METHODS

We evaluated patients with PDAC who underwent Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) somatic and germline testing from an institutional database. DNA isolated from tumor tissue and matched normal peripheral blood were sequenced by MSK-IMPACT. In patients with gBRCA1-PDAC, we examined the somatic BRCA1 mutation status and promotor methylation status of the tumor BRCA1 allele via a methylation array analysis. In patients with sufficient remaining DNA, a second methylation analysis by pyrosequencing was performed.

RESULTS

Of 1012 patients with PDAC, 19 (1.9%) were identified to harbor a gBRCA1 P/LPV. Fifteen patients underwent a methylation array and the mean percentage of BRCA1 promotor methylation was 3.62%. In seven patients in whom sufficient DNA was available, subsequent pyrosequencing confirmed an unmethylated BRCA1 promotor. Loss of heterozygosity was detected in 12 of 19 (63%, 95% confidence interval 38-84) patients, demonstrating loss of heterozygosity is the major molecular mechanism of BRCA1 inactivation in PDAC. Two (10.5%) cases had a somatic BRCA1 mutation.

CONCLUSIONS

In patients with gBRCA1-P/LPV-PDAC, loss of heterozygosity is the main inactivating mechanism of the wild-type BRCA1 allele in the tumor, and methylation of the BRCA1 promoter is a distinctly uncommon occurrence.

Feasibility and utility of synthetic control arms derived from real-world data to support clinical development

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Background: ‘Synthetic’ control arms (SCAs), created using electronic health records (EHRs), have immense potential to augment clinical trial findings and provide a rich context of real-world evidence (RWE) while reducing patient (pt) and sponsor burden (Gottlieb 2019). PICI0002 (PRINCE) is a ph1b/2 study evaluating APX005M with gemcitabine (gem) and nab-paclitaxel (NP) ± nivolumab for the treatment of metastatic pancreatic adenocarcinoma (mPDAC; NCT03214250). PRINCE pts were enrolled from select US academic cancer centers and a global, ph3 study was utilized for an historical reference control (Von Hoff 2013). To address the perceived limitations of this design, we explored the feasibility and utility of developing a contemporary SCA using real-world data (RWD). Methods: The SCA was derived using retrospective pt data from the two highest enrolling participating centers on PRINCE. Pts meeting key PRINCE eligibility criteria, who received gem/NP in the two years preceding the trial start date, were identified using an electronic phenotyping algorithm applied to cancer registry and EHR data, followed by manual review. Baseline characteristics, treatment exposure, efficacy and survival data were extracted electronically and via manual chart abstraction. Data were stored in a REDCap database built and housed by the Parker Institute for Cancer Immunotherapy. SCA pt characteristics were compared with PRINCE and overall survival (OS; time from initiation of gem/NP to death) was compared to historical reference controls (Table). Results: N=68 pts treated with gem/NP meeting PRINCE eligibility criteria were identified. All pts were deceased at the time of analysis. SCA pts had comparable baseline characteristics to PRINCE pts; key differences included inferior performance status and a higher proportion of pts presenting with a de novo mPDAC diagnosis. Median time on gem/NP was 4.8 months (mos; range 0-39). Median OS was 11.5 mos (95% CI 9.0-13.6) and 1-year OS was 43% (95% CI 31-55), in line with historical controls (Table). Conclusions: This study confirms the feasibility and utility of generating a control arm via a semi-automated approach. Current limitations entail manual oversight requirements as well as the known constraints of RWD, including associated biases and lack of available RECIST data. These limitations stand to evolve alongside EHR technologies. SCAs using RWD may help inform the value of prospective data by providing a contemporary reference of RWE. In some circumstances, SCAs may also serve as an alternative to traditional control arms, particularly for well-characterized standard therapies.[Table: see text]

Tucatinib in the treatment of HER2-overexpressing gastrointestinal cancers: current insights and future prospects

INTRODUCTION

Over the past 20 years, the treatment landscape of HER2-amplified tumors has considerably evolved. Until now, no approved targeted therapies were available for patients with HER2-amplified metastatic colorectal cancer (mCRC). Tucatinib, a highly selective tyrosine kinase inhibitor, demonstrated significant efficacy in combination with trastuzumab in patients with refractory mCRC, leading to its approval by the Food and Drug Administration (FDA).

AREAS COVERED

This review dives into the efficacy of tucatinib-based regimens in gastrointestinal malignancies, with a focus on the pivotal MOUNTAINEER trial, which led to the FDA approval of tucatinib plus trastuzumab in chemo-refractory HER2-amplified mCRC. Additionally, ongoing trials are exploring tucatinib in earlier treatment lines and across other gastrointestinal cancers, including biliary tract, gastric, and pancreatic malignancies. The mechanistic basis of dual HER2 inhibition and its implications for clinical practice are discussed.

EXPERT COMMENTARY

The future of tucatinib-based therapeutic strategies in GI malignancies depends on their integration into different treatment lines. Addressing acquired resistance using liquid biopsy-guided strategies and other TKIs like lapatinib will be paramount to improve outcomes.

Insurance disparity in the United States cancer survivors’ smoking rates: A trend study from NHIS 2008-2017

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Background: Smoking rates have been decreasing in the U.S over the last decade. Smoking cessation is a critical part of cancer treatment and survivorship care. However, little is known about the trend of smoking rates in U.S. cancer survivors and how it varied by individuals’ insurance coverages. Methods: We conducted a retrospective study to evaluate the temporal trend of smoking rates using the National Health Interview Survey from 2008 through 2017. Adult cancer survivors (n = 20122) were included in the analysis. The outcomes were self-reported current smoking behavior. Insurance coverage was categorized into any private (age ≤65), other coverage (age ≤65), uninsured (age ≤65), Medicare + any private (age > 65), and other coverage (age > 65). We combined every two years data to improve statistical power in the subgroup analysis. Weighted analyses were performed with SAS 9.4 to account for the complex design. Results: The smoking rates in cancer survivors decreased from 18.4% in 2008 to 12.5% in 2017. However, the smoking rates varied remarkably by insurance status (p < 0.001). There was a decreasing trend of smoking rates in participants with any private (age ≤65) (17.3% in 2008/2009 to 12.0% in 2016/2017), Medicare + any private (age > 65) (7.5% in 2008/2009 to 5.9% in 2016/2017), and other coverage (age > 65) (13.2% in 2008/2009 to 9.2% in 2016/2017) whereas the current smoking rates remains high in cancer survivors with other coverage (age ≤65) (40.1% in 2008/2009 to 34.4% in 2016/2017) and uninsured (age ≤65) (43.4% in 2008/2009 to 43,1% in 2016/2017). Conclusions: Cancer survivors report less smoking behaviors over the last decade which is similar to the general population. However, the smoking rate remains dangerously high in non-elderly cancer survivors without any private insurance.

Medical marijuana knowledge and attitudes amongst internal medicine residents

BACKGROUND

Mounting evidence suggests the safety and efficacy of medical marijuana (MM) in treating chronic ailments, including chronic pain, epilepsy, and anorexia. Despite incremental use of medical and recreational cannabinoids, current limited evidence shows generalized unpreparedness of medical providers to discuss or recommend these substances to their patients. Herein, the present study aims to examine internal medicine residents' knowledge of marijuana and their attitude towards its medical use.

METHODS

This is a descriptive cross-sectional study. A survey with 12 standardized queries was created and distributed among the internal medicine residents from Mount Sinai Morningside-West (MSMW) program from July 2020 to December 2020. Participants included preliminary and categorical residents from post-graduate years one to three. The survey consisted of self-assessment of residents' knowledge on the indication, contraindication, adverse effects of MM.

RESULTS

Eighty-six (59%) out of 145 residents completed the questionnaire. Despite most trainees (70%) having considered certifying the use of MM for their patients, over 90% reported none to little knowledge on its use. Approximately 80% of the surveyed residents expressed willingness to receive an appropriate educational curriculum.

CONCLUSION

To the best of our knowledge, this is the first study that indicated a critical lack of medical marijuana-related knowledge in surveyed internal medicine residents. In a population with growing cannabis consumption, physician training on the indication, toxicity, and drug interaction of cannabinoids is warranted.

Changes on Dynamic Cerebral Autoregulation Are Associated with Delayed Cerebral Ischemia in Patients with Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Early identification of vasospasm prior to symptom onset would allow prevention of delayed cerebral ischemia (DCI) in aneurysmal subarachnoid hemorrhage (aSAH). Dynamic cerebral autoregulation (DCA) is a noninvasive means of assessing cerebral blood flow regulation by determining independence of low-frequency temporal oscillations of systemic blood pressure (BP) and cerebral blood flow velocities (CBFV).

METHODS

Eight SAH patients underwent prospectively a median of 7 DCA assessments consisting of continuous measurements of BCFV and BP. Transfer function analysis was applied to calculate average phase shift (PS) in low (0.07-0.2 Hz) frequency range for each hemisphere as continuous measure of DCA. Lower PS indicated poorer regulatory response. DCI was defined as a 2-point decrease in Glasgow Coma Score and/or infarction on CT.

RESULTS

Three subjects developed symptomatic vasospasm with median time-to-DCI of 9 days. DCI was significantly associated with lower PS over the entire recording period (Wald = 4.28; p = 0.039). Additionally, there was a significant change in PS over different recording periods after adjusting for DCI (Wald = 15.66; p = 0.001); particularly, a significantly lower mean PS day 3-5 after bleed (14.22 vs 27.51; p = 0.05).

CONCLUSIONS

DCA might be useful for early detection of symptomatic vasospasm. A larger cohort study of SAH patients is currently underway.

Clinicomolecular Profile and Efficacy of Human Epidermal Growth Factor Receptor 2 (HER2)-Targeted Therapy for HER2-Amplified Advanced Biliary Tract Cancer

PURPOSE

This study aimed to investigate the clinicomolecular profiles and the efficacy of human epidermal growth factor receptor 2 (HER2)-targeted therapy in HER2-amplified biliary tract cancer (BTC).

METHODS

This study was an international collaboration that used combined data from the prospective SCRUM-Japan GOZILA and MONSTAR-SCREEN in Japan and retrospective reviews in the United States; patients with advanced BTC who had received systemic therapy were included. The clinicomolecular profiles were evaluated in an exploratory cohort, whereas the efficacy of HER2-targeted therapy was assessed in a biomarker-selected cohort.

RESULTS

Of the 439 patients in the exploratory cohort, 43 (10%) had HER2 amplification. The frequencies of coalterations were higher in patients with HER2 amplification versus patients without HER2 amplification including HER2 mutations (26% v 5%, P < .001), TP53 mutations (84% v 61%, P = .003), and BRAF amplification (9% v 2%, P = .030). There were no KRAS mutations identified in patients with HER2-amplified BTC. No significant difference in overall survival (OS) was observed between patients with and without HER2 amplification (median, 17.7 v 16.9 months; hazard ratio [HR], 0.95 [95% CI, 0.65 to 1.40]). Of the 60 patients with HER2-amplified BTC in the biomarker-selected cohort (43 from Japan and 17 from the United States), the OS was significantly longer in 29 patients who received HER2-targeted therapy than in those who did not receive HER2-targeted therapy (median, 24.3 v 12.1 months; HR, 0.39 [95% CI, 0.23 to 0.82]). Multivariate analysis identified HER2-targeted therapy as an independent prognostic factor for OS (HR, 0.29 [95% CI, 0.14 to 0.58]; P < .001).

CONCLUSION

HER2 amplification was found in 10% of advanced BTC and was not identified as an independent prognostic factor for OS. Patients with HER2-amplified BTC derive significant benefit from HER2-targeted therapy.

Effect of Intracranial Stenosis Revascularization on Dynamic and Static Cerebral Autoregulation

INTRODUCTION

Severe intracranial stenosis might lead to acute cerebral ischemia. It is imperative to better assess patients who may benefit from immediate reperfusion and blood pressure management to prevent injury to peri-infarct tissue.

METHODS

We assessed cerebral autoregulation using static and dynamic methods in an 81-year-old woman suffering acute cerebral ischemia from severe intracranial stenosis in the petrous segment of the left internal carotid artery (LICA).

RESULTS

Static cerebral autoregulation, which is evaluated by magnetic resonance imaging and magnetic resonance perfusion studies showed a progression of infarcts and a large perfusion-diffusion mismatch in the entire LICA territory between the second and third days after onset despite maximized medical therapy. Dynamic methods, including transfer function analysis and mean velocity index, demonstrated an increasingly impaired dynamic cerebral autoregulation (DCA) on the affected side between these days. Revascularization through acute intracranial stenting resulted in improved perfusion in the LICA territory and normalization of both dynamic and static cerebral autoregulation.

CONCLUSION

Thus, DCA, a noninvasive bedside method, may be useful in helping to identify and select patients with large-vessel flow-failure syndromes that would benefit from immediate revascularization of intracranial atherosclerotic disease.

Abstract TP34: Malignant CT Perfusion Profile is Associated With Increased Sensitivity to Blood Pressure Reductions During Endovascular Stroke Therapy

Background: After large-vessel occlusion (LVO), blood flow to the ischemic penumbra largely depends on collateral perfusion. Blood pressure (BP) reductions during endovascular therapy (EVT) have been associated with increased infarct size and unfavorable functional outcome. We hypothesized that patients with poor collateral circulation assessed using CT perfusion imaging are at increased risk for infarct progression associated with intraprocedural BP reductions.

Methods: We prospectively enrolled 90 patients with LVO stroke who underwent perfusion imaging and EVT at two comprehensive stroke centers. Volumes of arterial tissue delay >10 seconds (ATD10) were estimated with RAPID software; a malignant profile was defined as ADT10 >100 ml. BP reduction was defined as the difference between baseline mean arterial pressure (MAP) at the start of EVT and the lowest MAP during the procedure. Sustained relative hypotension was calculated as the area between baseline MAP and continuous measurements of intraprocedural MAP.

Results: Sixty-seven patients (mean age 67 ± 15, 38 F, mean NIHSS 16) who were successfully revascularized (TICI 2B/3) were included in analysis. Mean baseline MAP was 119 ± 23 mmHg and median BP reduction was 28 (IQR 20 - 53). These values did not differ significantly among those with malignant (n=19) and non-malignant (n=48) collateral profiles, yet average infarct volume on follow-up was significantly greater among patients with poor collaterals (65 mL vs 32 ml) after adjusting for age and admission NIHSS (p=0.029). A significant interaction was found between the malignant collateral profile and intraprocedural BP reduction (p=0.02, Figure 1A&B).

Conclusions: Patients with malignant collateral profiles are more sensitive to BP reductions during EVT, leading them to develop significantly larger infarcts. These results emphasize the importance of intraprocedural blood pressure management for this at-risk group.

Clinical benefit of granulocyte-colony stimulating factor (GCSF) use during chemoimmunotherapy treatment for metastatic pancreatic adenocarcinoma (mPDAC)

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Background: GCSF is used for primary/secondary prophylaxis of chemotherapy(chemo)-associated neutropenia in patients (pts) with mPDAC. GCSF may also increase the populations of healthy, naïve immune cells in an otherwise immunologically dysregulated and cold environment, potentially augmenting therapy outcome with immunomodulatory (IO) agents. Here, we describe the impact of GCSF administration on OS, PFS, and time on treatment (TOT) in the setting of mPDAC for (1) a trial in which pts were administered chemo-IO combinations and (2) a synthetic control arm using retrospective real-world data from pts who received standard-of-care (SOC) chemo (PASCAL). Methods: PRINCE is a ph1b/2 study evaluating gemcitabine (gem) and nab-paclitaxel (NP) ± sotigalimab (sotiga; CD40 agonist) ± nivolumab (nivo; anti-PD1) for pts with mPDAC (NCT0324250), where prophylactic GCSF use was prohibited. PASCAL pts received SOC gem/NP and primary/secondary GCSF use was allowed. In this retrospective analysis, GCSF use was defined as receiving at least 1 dose of GCSF anytime during treatment. OS, PFS, and TOT and associated HRs and CIs were calculated using Kaplan-Meier and Cox methods. PFS data not available for PASCAL. Results: 32/123 (26%) and 16/68 (24%) pts received GCSF in PRINCE and PASCAL, with 84% and 88% of pts receiving at least 1 dose within the first 3 cycles, respectively. In PRINCE, GCSF use was associated with significant improvements in OS (HR [95% CI]: 0.62 [0.40-0.97]), PFS (0.71 [0.47-1.08]), and TOT (0.67 [0.45-1.01]). These improvements were most notable in the sotiga-containing arms (table). In the absence of IO treatment, however, no statistical significance was observed in PASCAL (HR [95% CI]: OS = 0.81 [0.44-1.51]; TOT = 0.90 [0.51-1.58]). Additional work is ongoing to understand the association of GCSF usage with known prognostic factors. Conclusions: These analyses suggest that GCSF use may enhance the clinical benefits of chemo-IO in mPDAC. These potential benefits of GCSF usage warrant further evaluation in other chemo-IO trials as well as prospective evaluation in pre-clinical and clinical settings. Clinical trial information: NCT03214250 . [Table: see text]

Abstract WP59: A Clot Burden Score Predicts Functional Outcome and Neurological Complications After Cerebral Venous Sinus Thrombosis

Background and purpose: Involvement of deep venous structures is associated with worse outcomes in patients with cerebral venous sinus thrombosis (CVST); however, the impact of clot burden has not been studied. The aim of this study was to assess the value of a novel quantitative clot burden score as an independent predictor of clinical outcomes.

Methods: We retrospectively reviewed all patients admitted to University of Iowa Health Care with CVST between 2004-2014. All patients received standard of care medical management per AHA/ASA recommendations. The degree of the thrombosis was categorized in admission MR venograms as (partial=1 vs. complete occlusion=2). Clot burden scores were computed as the sum of the thrombosis degree in the following vessels: cerebral veins (cortical veins, internal cerebral, vein of Rosenthal, vein of Galen) and cerebral sinuses (superior sagittal, inferior sagittal, straight, torcula, transverse/sigmoid). The primary outcome was modified Rankin Scale (mRS) at discharge. Secondary outcomes included hemorrhage, infarction, and cerebral edema. Multiple regressions were conducted to examine effects of clot burden scores on each of the four outcomes.

Results: 115 patients met inclusion criteria, 76 women, and mean age 42. Thrombosis in cerebral veins area was noted in 58(50%), clot burden score Median=4, IQR=2; while 108(96%) had thrombosis in the cerebral sinuses area, Median=4, IQR=5. Clot burden in cerebral veins (p=.005) but not in cerebral sinuses, was associated with worse discharge mRS, r= .22. This effect remained significant when adjusting for age and gender (p=.002), but not when adjusting for complications including ICH, infarct, edema. Importantly, higher clot burden score in the cerebral veins predicted ICH (OR=1.73, p<.001), infarct size (OR=1.66, p<.001), and edema (OR=1.71, p<.001).

Conclusion: Quantitative clot burden measurement of the cerebral veins conveys additional prediction on outcomes of CVST. Our findings suggest that the worse clinical outcomes associated with clot burden in the cerebral veins may be mediated by ICH, infarct size, and/or edema. The structural differences between the cerebral veins and sinuses may play a role in the variability in clinical outcomes among patients with CVST.

Update on Emerging Therapies for Advanced Colorectal Cancer

Colorectal cancer (CRC) is the third most common malignancy worldwide. It is projected to increase by 3.2 million new cases and account for 1.6 million deaths by 2040. Mortality is largely due to limited treatment options for patients who present with advanced disease. Thus, the development of effective and tolerable therapies is crucial. Chemotherapy has been the backbone of systemic treatment of advanced CRC, but utility has been limited because of invariable resistance to therapy, narrow mechanisms of action, and unfavorable toxicity profile. Tumors that are mismatch repair-deficient have demonstrated remarkable response to immune checkpoint inhibitor therapy. However, most CRC tumors are mismatch repair-proficient and represent an unmet medical need. Although ERBB2 amplification occurs only in a few cases, it is associated with left-sided tumors and a higher incidence of brain metastasis. Numerous combinations of HER2 inhibitors have demonstrated efficacy, and antibody-drug conjugates against HER2 represent innovative strategies in this area. The KRAS protein has been classically considered undruggable. Fortunately, new agents targeting KRAS G12C mutation represent a paradigm shift in the management of affected patients and could lead the advancement in drug development for the more common KRAS mutations. Furthermore, aberrant DNA damage response is present in 15%-20% of CRCs, and emerging innovative combinations with poly (ADP-ribose) polymerase (PARP) inhibitors could improve the current therapeutic landscape. Multiple novel biomarker-driven approaches in the management of patients with advanced CRC tumors are reviewed in this article.

Systemic therapy for pretreated advanced biliary tract cancer: past developments and recent advances

Biliary tract cancer (BTC) remains among the most challenging malignancies with a poor prognosis and limited treatment options, particularly in pretreated patients. As most patients experience disease progression after first-line treatment, effective second-line and subsequent treatments are required. Although the addition of modified FOLFOX (fluorouracil, leucovorin, and oxaliplatin) to active symptom control improved the overall survival of patients with progressing advanced BTC despite gemcitabine plus cisplatin treatment, its efficacy was modest. Moreover, most clinical trials demonstrated modest efficacy of molecular-targeted agents for molecularly unselected pretreated advanced BTC. Patients with advanced BTC carry a relatively high druggable genetic alteration rate and have shown promising responses to molecular-matched therapies targeting gene alterations such as FGFR2 fusions/rearrangements, IDH1 mutation, and HER2 overexpression/amplification. Additionally, tumor-agnostic approaches, including BRAF V600E, NTRK fusion, and RET fusion, have expanded the treatment options for some patients. Immune checkpoint inhibitors have shown limited efficacy as mono- or combination therapy in patients with pretreated advanced BTC. Therefore, developmental efforts have shifted to immune checkpoint inhibitor and other combinations such as vascular endothelial growth factor receptor inhibitors or radiation. In addition to refining combination strategies to enhance the therapeutic potential of immune checkpoint inhibitor, future research should focus on elucidating the tumor microenvironment. This review delineates the evolution of systemic therapies in patients with pretreated advanced BTC. By examining past developments and recent advances through prospective trials, it highlights novel approaches that may improve outcomes in this challenging disease.

Overcoming Financial and Access Barriers in Global Cancer Care With Low-Dose Immunotherapy: A Systematic Review

PURPOSE

Immune checkpoint inhibitors (ICIs) have significantly improved outcomes in various malignancies. However, the high cost of these therapies limits access for much of the global population. This systematic review aims to evaluate the efficacy of low-dose ICIs compared with standard doses in different malignancies, addressing financial and access barriers in global cancer care.

METHODS

We conducted a systematic review of studies comparing the efficacy of low-dose versus standard-dose ICI regimens in advanced solid tumors. A comprehensive search was performed across multiple electronic databases, including retrospective and prospective studies. Excluded were animal studies, editorials, conference papers, book chapters, and other immunotherapy modalities. Outcomes assessed included overall survival (OS), progression-free survival, and objective response rate. Results were summarized descriptively due to study heterogeneity.

RESULTS

From 1,010 screened articles, four studies with 435 Asian patients were included, covering a variety of solid tumors. All included studies were with a low quality of evidence and a high risk of bias due to retrospective design. Two studies used weight-based dosing (pembrolizumab <2 mg/kg and nivolumab <2.15 mg/kg), showing similar OS to standard dosing in non-small cell lung cancer (NSCLC) and renal cell carcinoma, respectively. Flat dose regimens in two studies (nivolumab 20 mg or 100 mg once every 3 weeks and pembrolizumab 100 mg once every 3 weeks) also demonstrated comparable OS in NSCLC.

CONCLUSION

Low-dose ICIs may offer equivalent clinical benefits to standard dosing, potentially reducing costs and expanding access in developing countries. Although awaiting more representative randomized clinical trials, weight-based ICI regimens could be a viable alternative in low- and middle-income countries.

Abstract WP394: Impact of MRI/A versus CTA/P versus Direct Angiosuite Triage Protocols in Stroke Care Performance and Outcome of Transferred Patients for Endovascular Thrombectomy

Introduction: Transferred thrombectomy patients face additional time delays that might worsen outcome when compared to direct admission. In 2015, we moved from an MRI/A to a CTA/P protocol to decrease treatment times in transferred patients. In 2017, we initiated a direct admission to angiosuite (DAN) strategy. Herein, we aim to describe procedural and clinical outcomes in transfer patients with acute LVO stroke triaged by these protocols.

Method: We reviewed demographics, clot location, and treatment times for all thrombectomies from 2013 to June 2018. Primary outcome was MRS at 90 days. Secondary outcomes were door to groin time, difference between NIHSS at admission and discharge (ΔNIHSS). Distributions are analyzed with Wilcoxon Rank, chi-squared and Fisher’s Exact Tests. Logistic regression is used to evaluate MRS and mortality outcomes and adjusted for clot location, admission NIHSS and tPA use.

Results: The analysis includes 178 patients: 25 MRI/A, 130 CT/A/P, and 23 DAN. The groups significantly differ by tPA (16% vs 4% vs 13%, p=0.03), NIHSS at arrival (median 16 vs 17 vs 21, continuous p=0.03) and clot location (ICA 8% vs 20% vs 35%, BA 24% vs 10% vs 26%, p=0.01) for MRI, CT, and DAN respectively. There is significant reduction in median door to groin time between all groups (MRI 170 min., CT 84 min., DAN 16 min., p<0.001). The median ΔNIHSS is significantly different between CT and MRI (10 vs 4, p=0.01) and borderline significant between DAN and MRI (11 vs 4, p=0.07). There is a trend towards decrease disability (MRS 4-5) for DAN patients when compared to MRI at both discharge (OR=0.847, 95% CI 0.18, 4.10) and 90 days (OR=0.38, 95% CI 0.07, 2.10). There is significant increased risk of mortality when comparing DAN and MRI at 90 days (p=0.02).

Conclusion: DAN is feasible with faster procedural times and may have clinical benefit in select patients. RCTs are needed to assess the advantages and harm of decreasing imaging in benefit of time.

Abstract TMP18: Heparin Resistance is an Independent Predictor of Poor outcome in Cerebral Venous Sinus Thrombosis

Background and purpose: Unfractionated Heparin (UFH) infusion represents the most commonly used therapy in the acute management of cerebral venous sinus thrombosis (CVST). effectiveness of heparin in reaching therapeutic anti-coagulation levels has not been well studied in this population. Identifying subgroup of patients who will not respond to Heparin may prove useful in studying alternative treatments such as the new oral anticoagulants and endovascular therapy. We aimed to evaluate the initial response to heparin infusion measured by partial thromboplastin time (PTT) and it implication in discharge outcome.

Methods: Retrospective review of all consecutive patients at University of Iowa Hospitals and Clinics between 2004-2014 with CVST was conducted. All patients were treated with initial weight based bolus (14units/kg) of UFH followed by infusion. Consecutive PTT values in the first 48hrs of admission were classified as either therapeutic (40-87), supra-therapeutic (>87), or resistant (<40). Then patients were classified as good responders if 80% of PTT values were in the therapeutic range, classified as adequate if 65-79% of PTT values were therapeutic; rest of patients were classified as non-responders. Univariate and multivariate regressions models were performed to assess the association with discharge mRS, the primary outcome.

Results: 115 patients met inclusion criteria (76 women), mean age was 42. Mean PTT was 44.8 (SD=18.6; 95%CI of 41.2-48.5) in the first 48 hours. Patients resistant to Heparin (44%) had significantly worse functional outcomes, mRS [95%CI 2.3-3.6], compared to good [41%, 95%CI 1.2-2.3] and adequate responders to Heparin [15%, 95%CI 0.5-2.3] (p=.003). Mean PTT in the first 48 hours predicted discharge mRS, r=-.28,p<.005 and this effect remained significant when age, sex, altered mental status at admission were controlled, p=.001.

Conclusion: A significant portion of patients that receive heparin do not reach therapeutic levels within the initial days after hospitalization, and this does not appear to be a consequence of disease burden in our population. Specifying clinical features that predict heparin resistance might help to identify patients that benefit from alternative anticoagulation therapies.