Exceptional Response to Erdafitinib in FGFR2-Mutated Metastatic Pancreatic Ductal Adenocarcinoma

Despite advances in cancer therapeutics, pancreatic ductal adenocarcinoma (PDAC) remains among the deadliest malignancies, with a poor prognosis at time of diagnosis. Research in PDAC has suggested that adaptive signaling in the tumor microenvironment may promote tumor proliferation and survival. Several FGFR fusion genes—specifically FGFR2—are involved with the creation and progression of cancer. These mutations are found in a variety of cancer types. This report presents a unique case of a young patient with stage IV PDAC with a known FGFR2 fusion. This molecular alteration afforded a remarkable response to FGFR inhibitor therapy, erdafitinib, after the patient experienced disease progression on multiple chemotherapy regimens.

Phase I trial of Bermekimab with nanoliposomal irinotecan and 5-fluorouracil/folinic acid in advanced pancreatic ductal adenocarcinoma

In this phase I dose-escalation trial, we assess the maximum tolerated dose (MTD) of Bermekimab in combination with Nanoliposomal Irinotecan (Nal-Iri) and 5-Fluorouracil/Folinic Acid (5-FU/FA). Secondarily, we investigate effects on weight, lean body mass, quality-of-life, the gut microbiome composition, inflammatory biomarkers, progression-free survival, and overall survival. This was a single-arm, open-label adaptive Bayesian dose-escalation study of Bermekimab combined with Nal-Iri and 5FU/FA in patients with advanced or locally advanced PDAC who failed gemcitabine-based chemotherapy. 22 patients enrolled between 2017 and 2019. 3 of 21 patients experienced dose-limiting toxicities attributable to the chemotherapy backbone. 58% (10/17) of patients exhibited weight stability. Physical performance status was preserved among all subjects. Patients reported improvements in quality-of-life metrics via QLQ-PAN26 questioner (-3.6, p = 0.18) and functional well-being (1.78, p = 0.02). Subjects exhibited a decrease in inflammatory cytokines, notably, vascular endothelial growth factor (-0.86, p = 0.017) with Bermekimab. Bermekimab treatment was associated with an increased abundance of gut health-promoting bacterial genera Akkermansia, with 3.82 Log2-fold change from baseline. In sum, Bermekimab is safe to be used in conjunction with Nal-Iri and 5-FU/FA chemotherapy. This benign toxicological profile warrants further Phase I/II investigation of Bermekimab in combinatorial strategies, and the impact of anti-IL-1α antibodies on the gut microbiome.Clinical trials registration: NCT03207724 05/07/2017.

Gut microbiome and pancreatic cancer cachexia: An evolving relationship

Nearly 80% of patients with pancreatic ductal adenocarcinoma (PDAC) develop cachexia along their disease course. Cachexia is characterized by progressive weight loss, muscle wasting, and systemic inflammation and has been linked to poorer outcomes and impairments in quality of life. Management of PDAC cachexia has historically involved a multidisciplinary effort comprised of nutritional support, pancreatic enzyme replacement therapy, and/or pharmacologic interventions. Despite current interventions to mitigate PDAC cachexia, a significant proportion of patients continue to die from complications associated with cachexia underscoring the need for novel insights and treatments for this syndrome. We highlight the feasibility and effectiveness of a recent enteral feeding prospective trial at our institution to improve cachexia outcomes in patients with advanced PDAC. Additionally, we were among the first to characterize the stool microbiome composition in patients with advanced PDAC receiving enteral feeding for the treatment of cachexia. Novel insights into the relationship between enteral nutritional support, cachexia, and the gut microbiome are presented. These promising results are discussed in the context of a potential ability to modulate the stool microbiome as a new interventional strategy to mitigate PDAC cachexia.

Genomic correlates of response to capecitabine and temozolomide (CAPTEM) in pancreatic neuroendocrine tumors

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Background: Despite the frequent use of capecitabine and temozolomide (CAPTEM) to treat metastatic, well-differentiated pancreatic neuroendocrine tumors (PNETs), no reliable genomic predictors of response currently exist. PNETs commonly harbor mutations in MEN1, ATRX, DAXX, and the PI3K/AKT/mTOR pathway. We sought to determine whether the mutational status of these genes correlates with response to CAPTEM. Methods: A retrospective cohort of PNET cases seen at Cedars-Sinai Medical Center or from Perthera’s Real-World Evidence Database included 23 patients who were treated with CAPTEM in 1st or 2nd line and had targeted next-generation sequencing (NGS) of their tumors available. Genomic alterations were correlated with progression-free survival (PFS) using multivariate Cox regression analysis. Results: We analyzed 23 PNET patients, 4 (17.4%) of whom had documented functional tumors. We identified MEN1 mutations as positively associated with CAPTEM response, but this effect was less pronounced for the subset with co-occurring DAXX mutations, which are commonly found alongside MEN1 alterations. With and without accounting for line of therapy, we found that PFS on CAPTEM was significantly longer in MEN1-mutated, DAXX-wildtype tumors compared to other mutation profiles ( P < 0.01, see Table). ATRX (67%) and PTEN (33%) alterations were also enriched in the MEN1-mutated/ DAXX-wildtype subset; however, other PI3K/AKT/mTOR alterations were common across all MEN1-mutated cases. Conclusions: We describe a novel genomic signature ( MEN1 mut/ DAXX wt) that correlates with PNET response to CAPTEM therapy and is exploratory in nature. Prospective validation of these associations is warranted while taking into account other therapies, histopathologic factors, and other genomic correlates. [Table: see text]

Impact of site-specific metastases on survival outcomes in pancreatic adenocarcinoma (PDAC) patients: A national analysis

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Background: PDAC is the third most fatal cancer, where most patients present with metastases at diagnosis. Previous studies, including a retrospective analysis from our single-center experience, suggests survival rates are significantly higher for those with lung-only metastases (mets) when compared to liver metastasis or other sites of metastases (liver+other). The objective of this analysis is to explore this difference based on sites and metastasis and the impact of chemotherapy from a national cohort. Methods: We identified PDAC patients (>18years) from with metastases to either 1) lung-only; 2) liver+other sites in the National Cancer Database diagnosed between 2010 and 2015.We analyzed patient characteristics, demographics, type of chemotherapy, and survival outcomes. Kaplan Meir survival curves were generated, and Cox proportional hazard models adjusted for age and sex were fit to evaluate associations between met site and survival. Survival was calculated from time of diagnosis to death and compared across mets site, receipt of chemotherapy, and treatment and type (single versus multi-agent). Results: 15359 PDAC patients were included in the analysis [51.6% male 48.4% female, mean age 69 years] of which 4512 (29.4%) patients had lung only mets and 10847 (70.6%) had liver + other mets. Median survival was 5.72 and 2.37 months for lung only vs. liver+other mets, respectively (log rank p<0.001). From a subset population of 8440 patients who received chemotherapy, median survival of 9.4 and 4.9 months for lung only and liver+other mets was observed, respectively [Table]. Median OS for single agent chemotherapy was 4.4 months (n=2637), with patients with lung only mets having a median OS of 7.1 months and those with liver+other mets having a median OS of 3.6 months. Median OS for patients treated with multi-agent chemotherapy (n=5380) was 7.4 months, with lung only met patients having a median OS of 11.6 months and those with liver+other mets having a median OS of 6.1 months. Hazard ratios (HR) and 95% confidence intervals (CI) are displayed in the table. Conclusions: In a national cohort, patients with metastatic PDAC and lung-only metastasis had improved survival when compared with liver +other metastasis. Further contemporary research is needed to understand the underlying biology that dictates the survival difference between lung metastasis vs other sites of metastatic disease in pancreatic cancer.[Table: see text]

Metabolomics in advanced pancreatic cancer (PC) patients (pts) achieving weight stability on enteral feeding for cachexia

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Background: We previously showed that enteral feeding was associated with weight stability and compositional changes in the gut microbiome with increased abundance of the gram-negative genera Veillonella over time. Here, we evaluated the potential of plasma metabolites as predictors of weight stability and high Veillonella abundance in enteral fed pts. Methods: The PANCAX-1 (NCT02400398) prospective trial enrolled 31 cachectic advanced PC pts to receive jejunal tube peptide-based diet for 12 weeks (wks) who were planned for standard chemotherapy. In preplanned exploratory analyses, serial blood samples were collected over 12 wks of enteral feeding. Up to 219 plasma metabolites were analyzed by mass spectrometry and high-performance liquid chromatography. Analytes were compared by relative area under the curve (AUC) and differences evaluated by two-sample t-tests. Pts were stratified by weight stable (WS, defined as weight change < 0.1 kg/baseline BMI-unit over 12 wks of enteral feeding) vs. weight unstable (WU) and high (HV) vs. low Veillonella (LV) abundance (defined by dichotomizing at the mean relative abundance in WS pts). Results: Of 31 cachectic pts enrolled into PANCAX-1, a total of 55 blood samples were collected from 28 pts for plasma metabolomics. Out of 16 evaluable pts, 62.5% receiving enteral feeding met the primary endpoint of weight stability at 12 wks. Plasma metabolomics in 10 pts showed that WU pts (n = 4) had significantly decreased levels of essential amino acids (AAs, L-histidine, L-phenylalanine) and non-essential AAs (L-citrulline, L-tyrosine, all p < 0.05) than WS pts (n = 6) at the end of 12 wks of enteral feeding. In 7 WS pts with complete serial sets of blood samples available, enteral feeding over 12 wks was associated with increases in markers of muscle mass (creatinine) but decreases in nucleotide precursors (all p < 0.05) compared to baseline. Comparison of baseline metabolites between 6 WS pts with HV and 4 WU pts with LV showed that HV was associated with increases in the nucleotide dCDP and essential AA L-isoleucine but decreased TCA cycle metabolite alpha-ketoglutarate (all p < 0.05). Decreases in lactic acid was observed at 12 wks of enteral feeding in HV pts when compared to baseline (p < 0.05). Conclusions: Our findings are hypothesis-generating in that metabolites unique to weight stability and Veillonella abundance may inform future studies of anti-cachexia therapies involving enteral feeding or microbial modulation.

Retrospective study of survival outcomes in patients with hereditary pathogenic and variants of unknown significance mutations in pancreatic adenocarcinoma

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Background: Since 2019, all patients with pancreatic adenocarcinoma (PDAC) are recommended to undergo germline testing per the National Comprehensive Cancer Network guidelines. Outside of PARP inhibitors in germline BRCA mutated PDAC, the predictive and prognostic implications of these genetic alterations are unclear. Many hereditable mutations are continually discovered, but the majority are considered Variants of Unknown Significance (VUS). The purpose of this retrospective study is to characterize the clinical characteristics of multiple pathogenic and VUS germline mutations in PDAC. Methods: An IRB approved institutional database of PDAC patients (n=442) was queried for patients diagnosed between 2007 and 2021. Only patients who tested positive for hereditary mutations (n=35) or VUS (n=41) were included. Patients with both pathogenic mutation and VUS were considered in the pathogenic mutation group. Results: 76 patients (35 pathogenic, 41 VUS) were included in the analysis. Pathogenic mutations were divided into subcategories including DNA repair (n=21), polyposis (n=2), pancreatitis-associated (n=11), and other (n=2). With a mean follow-up period of 636 days, the overall survival (OS) for pathogenic mutations at 90 days, 180 days, 1 year, and 2 years was 100%, 97.1%, 88.6%, and 74.3% respectively. The cumulative recurrence was 2.9%, 11.4%, 22.9%, and 37.1%. For VUS, the OS was 97.6%, 95.1%, 75.6%, and 56.1% and cumulative recurrence was 0%, 14.6%, 31.7%, and 43.9% in the same time intervals. Conclusions: This data suggests that patients with germline mutations may have favorable outcomes when compared to the general population. Overall germline alterations in our intuitional cohort had a 2-year survival of nearly 75%. Notably, pancreatitis-associated hereditable mutations consisted a sizeable portion of our overall cohort. Although current therapy is most focused on DNA repair mechanisms, these results show that other novel germline genetic alterations may be prognostic and warrant further investigation.[Table: see text]

Real-world clinical outcomes and molecular features of lung-specific and liver-specific metastases in pancreatic ductal adenocarcinoma (PDAC)

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Background: PDAC remains one of the most lethal malignancies following metastatic presentation, typically to the liver or lung. Previous studies have observed that advanced PDAC patients have variable outcomes depending on site of involvement. Here, we aim to understand survival outcomes and molecular features for PDAC based on involvement of lung vs liver. Methods: We retrospectively analyzed longitudinal clinical outcomes across 787 patients with PDAC with next generation sequencing (NGS) from Perthera’s Real-World Evidence database whose tumors first metastasized to either the lung or the liver. Median overall survival (mOS) was measured from either the date of initial diagnosis (resectable cases only, stage I-III) or advanced diagnosis (stage IV) until death. Differences in survival and frequencies of mutations were evaluated between patients with lung-specific and liver-specific metastases using Cox regression and Fisher's exact test, respectively. Results: Among resectable PDAC, mOS from initial diagnosis was significantly shorter in patients that developed liver only metastasis (Table, left) compared to those patients that developed lung only metastasis (p=2.4e-08, HR=3.04 [2.06-4.49]). In the advanced PDAC cohort, mOS from diagnosis of advanced disease was also significantly shorter (Table, right) in liver only versus lung only metastasis (p=0.0013, HR=1.62 [1.21-2.18]). Differences in treatment-specific outcomes were not significant supporting a potential prognostic role for lung only metastases. PDAC tumors presenting to the liver first were modestly enriched (unadjusted p<0.05) for TP53 mutations (81.4% in liver vs 69.2% in lung), MYC amplifications (8.6% vs 3.0%), and inactivating CDK2NA alterations (51.5% vs 39.1%) whereas lung-specific mutation frequencies were higher for STK11 mutations (2.4% in liver vs 7.5% in lung), CCND1 amplifications (0.5% vs 3.0%), GNAS alterations (2.0% vs 8.5%). No differences in KRAS mutations nor specific isoforms were noted between lung vs liver only metastasis. Conclusions: Lung only metastasis in both resectable and advanced PDAC confers a significant survival advantage compared to liver only metastasis. Deeper investigation into the molecular drivers of site-specific metastases is warranted.[Table: see text]

Race, sex, age, and geographic disparities in pancreatic cancer incidence

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Background: Pancreatic cancer has a poor prognosis and a 5-year survival rate of 10%. A population-risk level analysis of pancreatic cancer will identify epidemiologic risk factors including geographic, racial, ethnic, and sex inequities which could lead to improved prevention strategies. Methods: Incidence data for invasive pancreatic cancer from 2009 through 2018 was obtained from the Surveillance, Epidemiology, and End Results Research (SEER) Plus Limited-Field database (SEER 21) that covers about 37% of the US population. Age-adjusted incidence rates (AAIR) and trends were estimated by race, sex, age categories (ten-year age groups starting from age 30), and county-level rural-urban classification developed by the United States Department of Agriculture (USDA). Trends over the period are described using the annual percent change (APC) calculated using weighted least squares method. Results: Overall pancreatic cancer incidence (per 100,000 population) for all ages during 2009-2018 was 13.0. Rates were highest among Black (15.4), followed by non-Hispanic white (13.2) and Hispanic (11.6) groups in both men and women. Males carries a higher rate of incidence (14.8) than females (11.6) in pancreatic cancer although both sexes experienced a 0.6% increase in incidence yearly. Incidence of pancreatic cancer increased with age across all ethnicities in men and women. The highest rate of incidence was found in ages 80 and above (99.5) and the lowest in age group 30-39 (1.0). Pancreatic cancer rates increased by 0.6% yearly and increased in every racial/ethnic group for both males and females, except Black males (0.0) and American Indian/Alaska Native females (-0.2). Although incidence in urban counties (13.1, n = 321) and rural counties (12.8, n = 411) was comparable, rural countries observed a faster increase in rates between 2009 and 2018 (p < 0.05). Conclusions: Incidence of pancreatic cancer has increased from 2009 to 2018 across all ethnicities and in both men and women. Minorities, males, and individuals living in rural counties are disproportionately affected by pancreatic cancer. Additionally, older individuals have a higher incidence of pancreatic cancer, suggesting an increased risk in this patient population. This data will inform strategies to identify high-risk populations and implement preventative care, screening, and surveillance.[Table: see text]

Advances in Pancreatic Ductal Adenocarcinoma Treatment

Pancreatic Ductal Adenocarcinoma (PDAC) is one of the deadliest malignancies among all cancers. Despite curative intent, surgery and the use of standard cytotoxic chemotherapy and radiation therapy, PDAC remains treatment-resistant. In recent years, more contemporary treatment modalities such as immunotherapy via checkpoint inhibition have shown some promise in many other malignancies, yet PDAC still eludes an effective curative treatment. In investigating these phenomena, research has suggested that the significant desmoplastic and adaptive tumor microenvironment (TME) of PDAC promote the proliferation of immunosuppressive cells and act as major obstacles to treatment efficacy. In this review, we explore challenges associated with the treatment of PDAC, including its unique immunosuppressive TME. This review examines the role of surgery in PDAC, recent advances in surgical approaches and surgical optimization. We further focus on advances in immunotherapeutic approaches, including checkpoint inhibition, CD40 agonists, and discuss promising immune-based future strategies, such as therapeutic neoantigen cancer vaccines as means of overcoming the resistance mechanisms which underly the dense stroma and immune milieu of PDAC. We also explore unique signaling, TME and stromal targeting via novel small molecule inhibitors, which target KRAS, FAK, CCR2/CCR5, CXCR4, PARP and cancer-associated fibroblasts. This review also explores the most promising strategy for advancement in treatment of pancreatic cancer by reviewing contemporary combinatorial approaches in efforts to overcome the treatment refractory nature of PDAC.

Neoadjuvant PET and MRI-based intensity modulated radiotherapy leads to less toxicity and improved pathologic response rates in locally advanced rectal cancer

Background

Neoadjuvant chemoradiation (NeoCRT) is standard of care for the treatment of locally advanced rectal cancer (LARC). Contemporary radiation techniques and pre-treatment imaging may impact toxicities and pathologic response (PR). Herein we compare intensity modulated radiotherapy (IMRT) and advanced pre-treatment imaging in the neoadjuvant treatment of LARC and resulting impact on toxicities and pathologic outcomes relative to 3 dimensional conformal radiotherapy (3DCRT).

Methods

LARC patients treated at 4 large academic centers in the US from 2007-2016 were reviewed. Patients received 5-FU-based NeoCRT concurrently with IMRT or 3DCRT. PR was recorded as none, partial, or complete. Common terminology for adverse events version 4 was used to grade toxicities. Toxicity rates were compared using Chi-square analysis. Multivariable models were fit adjusting for age, gender, pre-tx CT to identify independent predictors of PR and toxicity.

Results

A total of 128 patients were analyzed: 60.1% male and 39.8% female, median age 57.7 years (range, 31-85 years). Clinical characteristics were similar across RT groups. The outcome of partial and complete PR was similar for IMRT and 3DCRT (48.1%, 23.1% vs. 31.7%, 23.3%), respectively. After adjusting for gender, age, and pre-RT chemotherapy type, IMRT and pretreatment PET and/or MRI imaging was significantly associated with increased odds for complete and partial response (OR =2.95, 95% CI: 1.21-7.25, P=0.018; OR =14.70, 95% CI: 3.69-58.78, P<0.0001). Additionally, IMRT was associated with reduced rates of dehydration, dermatitis, rectal pain, rectal bleeding, and diverting ostomy (P<0.05). Overall rates of grade 2 and higher toxicities were significantly reduced in IMRT vs. 3DCRT after adjusting for confounders (OR =0.27, 95% CI: 0.08-0.87).

Conclusions

NeoCRT IMRT with pretreatment PET and/or MRI for LARC leads to reduced acute toxicities and improved PR compared to 3DCRT. Given the challenges associated with prospective validation of these data, IMRT with pretreatment PET and/or MRI should be considered standard treatment for LARC.

Impact of chemoradiotherapy on PD1/PDL1 expression and clinical outcomes in gastroesophageal cancers

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Background: Expression of the immune modulating proteins, programmed death receptor-1 (PD1) and its ligand (PDL1), in gastrointestinal malignancies is associated with poor prognosis. PD1/PDL1 expression levels have also been identified as predictors of response to checkpoint inhibition. Minimal data is available on how expression of PD1 and PDL1 is influenced by chemoradiotherapy (CRT). In this study, we investigated the relationship between PDL1/PD1 expression, CRT, and clinical outcomes in gastroesophageal (GE) cancer. Methods: With IRB approval, we identified 28 patients with gastric cardia or GE junction tumors who underwent neoadjuvant standard CRT followed by surgical resection. Pre-CRT biopsies and post-CRT surgical specimens were analyzed using quantitative immunohistochemistry for the expression of PDL1 and PD1. Samples were categorized as trace-low (TL) or moderate-high (MH) expressors of PDL1 and PD1. The impact of these and other clinical and pathologic variables on overall survival (OS) was assessed using multivariate cox proportional hazards modeling. Co-expression of PDL1 and PD1 in matched samples was determined by regression analysis. Results: Following CRT, PDL1 and PD1 expression increased in 54% and 32% of patients, respectively. On multivariate analysis, patients with MH expression of PD1 after CRT irrespective of pre-CRT expression levels had a significant decrease in OS compared to those with TL expression (median survival 23.1 vs 74.1 months; HR,3.31; CI,1.05-10.35; p = 0.039). In patients with gastric confined tumors, an increase in PD1 expression from TL to MH after CRT was associated with significantly lower OS rates (p = 0.003). Regression analysis of PD1 to PDL1 was significant (p < 0.01) both before and after CRT, with a correlation coefficient of 0.34 in pre-CRT and 0.49 in post-CRT specimens. Conclusions: Elevated expression of PD1 is associated with poor OS in patients with GE cancer. Neoadjuvant CRT upregulates both PDL1 and PD1. In gastric cancer patients, this led to significantly worse survival. These data identify potential mechanisms of resistance and suggest a role for checkpoint inhibitors in combination with CRT.