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Featured researches published by Thomas DeLeon.


Hepatology | 2018

Surveillance for hepatobiliary cancers in patients with primary sclerosing cholangitis

Ahmad H. Ali; James H. Tabibian; Navine Nasser-Ghodsi; Ryan J. Lennon; Thomas DeLeon; Mitesh J. Borad; Moira Hilscher; Marina G. Silveira; Elizabeth J. Carey; Keith D. Lindor

Primary sclerosing cholangitis (PSC) is a risk factor for cholangiocarcinoma (CCA) and gallbladder carcinoma (GBCa). Surveillance for GBCa is recommended, but the clinical utility of surveillance for other hepatobiliary cancers (HBCa) in PSC, namely CCA and hepatocellular carcinoma (HCC), remains unclear. We aimed to determine whether surveillance is associated with better survival after diagnosis of HBCa in patients with PSC. Medical records of PSC patients seen at the Mayo Clinic Rochester from 1995 to 2015 were reviewed. Patients were included if they had ≥1 year of follow‐up and developed HBCa. Patients were categorized according to their surveillance status (abdominal imaging, carbohydrate antigen 19‐9, and alpha‐fetoprotein). The primary endpoints were HBCa recurrence, HBCa‐related death, and all‐cause mortality. Overall survival was assessed by the Kaplan‐Meier survival method; HBCa‐related survival was assessed using competing risk regression. Tests of significance were two‐tailed, and a P value <0.05 was considered statistically significant. From 1995 to 2015, a total of 79 of 830 PSC patients were diagnosed with HBCa. Cumulative follow‐up was 712 and 283 person‐years pre‐ and post‐HBCa diagnosis, respectively. Seventy‐eight percent of patients (54/79) developed CCA, 21% (17/79) HCC, 6% (5/79) GBCa, 3% (2/79) both CCA and HCC, and 1% (1/79) both HCC and GBCa. Fifty‐one percent (40/79) were under HBCa surveillance, and 49% (39/79) were not. Patients in the surveillance group had significantly higher 5‐year overall survival (68% versus 20%, respectively; P < 0.001) and significantly lower 5‐year probability of experiencing an HBCa‐related adverse event (32% versus 75%, respectively; P < 0.001) compared with the no‐surveillance group. Conclusion: This study demonstrates that HBCa surveillance significantly improves outcomes, including survival, in patients with PSC. (Hepatology 2018;67:2338‐2351).


Future Oncology | 2018

Novel targeted therapy strategies for biliary tract cancers and hepatocellular carcinoma

Thomas DeLeon; Daniel H. Ahn; James M Bogenberger; Panos Z. Anastasiadis; Mansi Arora; Ramesh K. Ramanathan; Bashar Aqel; George Vasmatzis; Mark J. Truty; Rahmi Oklu; Tanios Bekaii-Saab; Mitesh J. Borad

Worldwide hepatobiliary cancers are the second leading cause of cancer related death. Despite their relevance, hepatobiliary cancers have a paucity of approved systemic therapy options. However, there are a number of emerging therapeutic biomarkers and therapeutic concepts that show promise. In hepatocellular carcinoma, nivolumab appears particularly promising and recently received US FDA approval. In intrahepatic cholangiocarcinoma, therapies targeting FGFR2 and IDH1 and immune checkpoint inhibitors are the furthest along and generating the most excitement. There are additional biomarkers that merit further exploration in hepatobiliary cancers including FGF19, ERRFI1, TERT, BAP1, BRAF, CDKN2A, tumor mutational burden and ERBB2 (HER2/neu). Development of new and innovative therapies would help address the unmet need for effective systemic therapies in advanced and metastatic hepatobiliary cancers.


JCO Precision Oncology | 2018

Cholangiocarcinoma With FGFR Genetic Aberrations: A Unique Clinical Phenotype

Apurva Jain; Mitesh J. Borad; Ying Wang; Reham Abdel-Wahab; Funda Meric-Bernstam; Keith A. Baggerly; Ahmed Kaseb; Humaid O. Al-Shamsi; Daniel H. Ahn; Thomas DeLeon; Andrea Grace Bocobo; Tanios Bekaii-Saab; Rachna T. Shroff; Milind Javle

PurposeFGFR genetic aberrations (GAs) occur in an estimated 10% to 16% of intrahepatic cholangiocarcinomas (CCAs). The natural history of CCA with FGFR GAs, the prognostic role of coexisting GAs, and the outcome with FGFR-targeted inhibitors are unknown.Patients and MethodsPatients with CCA with FGFR GAs were identified using next-generation sequencing or fluorescence in situ hybridization from four tertiary cancer centers and compared with FGFR wild-type counterparts. Data reviewed included demographic, treatment, overall survival (OS), and GA data. Fisher’s exact test, Kaplan-Meier plots, and log-rank tests were used for statistical analysis.ResultsThree hundred seventy-seven patients with CCA were identified, and 95 had FGFR GAs. FGFR2 GA was most common (n = 74, with 63 fusions) and seen in intrahepatic CCA. In patients with CCA, FGFR GAs occurred more frequently in younger patients (≤ 40 years; 20%) compared with older patients (> 40 years; 6.7%; P < .001), presented at an earlier stage (TNM stage I/...


Oncolytic Virotherapy | 2017

Oncolytic virus delivery: from nano-pharmacodynamics to enhanced oncolytic effect

Raquel Yokoda; Bolni Marius Nagalo; Brent Vernon; Rahmi Oklu; Hassan Albadawi; Thomas DeLeon; Yumei Zhou; Jan B. Egan; Dan G. Duda; Mitesh J. Borad

With the advancement of a growing number of oncolytic viruses (OVs) to clinical development, drug delivery is becoming an important barrier to overcome for optimal therapeutic benefits. Host immunity, tumor microenvironment and abnormal vascularity contribute to inefficient vector delivery. A number of novel approaches for enhanced OV delivery are under evaluation, including use of nanoparticles, immunomodulatory agents and complex viral–particle ligands along with manipulations of the tumor microenvironment. This field of OV delivery has quickly evolved to bioengineering of complex nanoparticles that could be deposited within the tumor using minimal invasive image-guided delivery. Some of the strategies include ultrasound (US)-mediated cavitation-enhanced extravasation, magnetic viral complexes delivery, image-guided infusions with focused US and targeting photodynamic virotherapy. In addition, strategies that modulate tumor microenvironment to decrease extracellular matrix deposition and increase viral propagation are being used to improve tumor penetration by OVs. Some involve modification of the viral genome to enhance their tumoral penetration potential. Here, we highlight the barriers to oncolytic viral delivery, and discuss the challenges to improving it and the perspectives of establishing new modes of active delivery to achieve enhanced oncolytic effects.


npj Precision Oncology | 2018

Emerging role of precision medicine in biliary tract cancers

James M Bogenberger; Thomas DeLeon; Mansi Arora; Daniel H. Ahn; Mitesh J. Borad

Biliary tracts cancers (BTCs) are a diverse group of aggressive malignancies with an overall poor prognosis. Genomic characterization has uncovered many putative clinically actionable aberrations that can also facilitate the prognostication of patients. As such, comprehensive genomic profiling is playing a growing role in the clinical management of BTCs. Currently however, there is only one precision medicine approved by the US Food and Drug Administration (FDA) for the treatment of BTCs. Herein, we highlight the prevalence and prognostic, diagnostic, and predictive significance of recurrent mutations and other genomic aberrations with current clinical implications or emerging relevance to clinical practice. Some ongoing clinical trials, as well as future areas of exploration for precision oncology in BTCs are highlighted.


Oncolytic Virotherapy | 2018

Oncolytic virotherapy in upper gastrointestinal tract cancers

Raquel Yokoda; Bolni Marius Nagalo; Mansi Arora; Jan B. Egan; James M Bogenberger; Thomas DeLeon; Yumei Zhou; Daniel H. Ahn; Mitesh J. Borad

Upper gastrointestinal tract malignancies are among the most challenging cancers with regard to response to treatment and prognosis. Cancers of the esophagus, stomach, pancreas, liver, and biliary tree have dismal 5-year survival, and very modest improvements in this rate have been made in recent times. Oncolytic viruses are being developed to address these malignancies, with a focus on high safety profiles and low off-target toxicities. Each viral platform has evolved to enhance oncolytic potency and the clinical response to either single-agent viral therapy or combined viral treatment with radiotherapy and chemotherapy. A panel of genomic alterations, chimeric proteins, and pseudotyped capsids are the breakthroughs for vector success. This article revisits developments for each viral platform to each tumor type, in an attempt to achieve maximum tumor selectivity. From the bench to clinical trials, the scope of this review is to highlight the beginnings of translational oncolytic virotherapy research in upper gastrointestinal tract malignancies and provide a bioengineering perspective of the most promising platforms.


Immunotherapy | 2018

Novel immunotherapy strategies for hepatobiliary cancers

Thomas DeLeon; Yumei Zhou; Bolni Marius Nagalo; Raquel Yokoda; Daniel H. Ahn; Ramesh K. Ramanathan; Marcela Salomao; Bashar Aqel; Amit Mahipal; Tanios Bekaii-Saab; Mitesh J. Borad

Despite recent advancements in therapeutic options for advanced hepatobiliary cancers, there remains an unmet need for innovative systemic treatments. Immunotherapy has shown an ability to provide prolonged clinical benefit, but this benefit remains limited to a small subset of patients. Numerous ongoing endeavors are investigating novel immunotherapy concepts. Immunotherapies that have demonstrated clinical efficacy in hepatobiliary cancers includexa0PD-1 inhibitor therapy andxa0CTLA-4 inhibitor therapy. Novel immunotherapy concepts include targeting emerging checkpoint proteins, bispecific T-cell engagers, combinatorial trials with checkpoint inhibitors, oncolytic virotherapy and chimeric antigen receptor T cells. The goal for these new treatment strategies is to achieve a meaningful expansion of patients deriving prolonged clinical benefit from immunotherapy.


Journal of gastrointestinal oncology | 2018

Pilot evaluation of PD-1 inhibition in metastatic cancer patients with a history of liver transplantation: the Mayo Clinic experience

Thomas DeLeon; Marcela Salomao; Bashar Aqel; Mohamad Bassam Sonbol; Raquel Yokoda; Ahmad H. Ali; Adyr A. Moss; David M. Chascsa; Jorge Rakela; Alan H. Bryce; Mitesh J. Borad


Journal of Clinical Oncology | 2018

The effect of neutropenic diets on infection and mortality rates in cancer patients: An updated systematic review and meta- analysis.

Mohamad Bassam Sonbol; Belal Firwana; Thomas DeLeon; Tania Jain


Journal of Clinical Oncology | 2018

Assessing clinical outcomes following liver transplantation in intrahepatic cholangiocarcinoma and mixed hepatocellular carcinoma-cholangiocarcinoma patients: The Mayo Clinic experience.

Thomas DeLeon; David D. Lee; Marcela Salomao; Marlene E. Girardo; Charles B. Rosen; Julie K. Heimbach; Adyr A. Moss; Amit Mathur; Denise M. Harnois; Bashar Aqel; Sumera Rizvi; Kabir Mody; Mohamad Bassam Sonbol; Heidi E. Kosiorek; Mitesh J. Borad

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