PhD in Biology, Baylor College of Medicine, Houston, Texas, 1996
MD, Faculdade de Medicina de Lisboa, Universidade de Lisboa, Portugal, 1984

Antonia R. Sepulveda MD, PhD is a professor in and chairwoman of the Department of Pathology at George Washington University (GW). She is an expert in gastrointestinal pathology and genomic and molecular diagnostic pathology.  Before joining GW, Dr. Sepulveda was the director of the Division of Gastrointestinal Pathology at Columbia University in New York, where she was also director of the gastrointestinal pathology fellowship program and vice-chair for translational research.

Her clinical practice provides specialized gastrointestinal, biliary and pancreas pathology diagnostic services with integration of molecular testing utilizing genomics and specific tumor biomarkers for personalized cancer management and precision medicine of digestive organ cancers and pre-cancer conditions (esophageal cancer and Barrett's esophagus, gastric, colorectal, pancreas, and biliary pre-cancer lesions and cancers).

Dr. Sepulveda is the medical director of the Genomic and Molecular Pathology division at GW University Department of Pathology, which provides testing for cancer and pre-cancer to meet the needs of precision cancer therapies and molecular virology testing, including COVID-19 SARS-CoV-2 testing.

Dr. Sepulveda's leadership is nationally and internationally recognized. She has been the lead co-chair for the “Molecular testing guidelines for colorectal cancer”, a combined initiative of the American Society for Clinical Pathology, College of American Pathologists Pathology and Laboratory Quality Center, Association for Molecular Pathology and the American Society of Clinical Oncology. Dr. Sepulveda has held many leadership positions and is currently President-elect and member of the Board of Directors of the Association for Molecular Pathology (AMP).

Dr. Sepulveda’s research laboratory receives funding from the NCI and is focused on innovative cancer and pre-cancer biomarkers to improve cancer prevention and treatment. The Sepulveda laboratory integrates cutting edge experimental approaches to define the molecular mechanisms and to discover biomarkers of gastric, esophageal, colorectal and pancreatic cancers and pre-cancer lesions. Dr. Sepulveda has over 170 publications (original research, reviews, chapters and books).

Clinical Expertise

Dr. Sepulveda’s clinical practice focus is to provide pathology diagnosis of digestive, pancreatic and biliary tract diseases with integration of molecular testing for personalized cancer therapies.

Dr. Sepulveda and her team provide diagnostic services for molecular pathology: mutation reports from Next Generation Sequencing gene panels, microsatellite instability, DNA mismatch repair IHC, PDL1 scores, HER2 amplification by CISH and other tests (link to genomic and molecular pathology diagnostic services at GW Department of Pathology).


The Sepulveda's Research Laboratory is located in the George Washington University Cancer Center.  Studies are centered primarily in digestive organ cancers (esophagus, stomach, colorectum, biliary tract and pancreas), toward discoveries of underlying molecular mechanisms, biomarkers for cancer risk, prediction of response to therapies and of inherited cancers.

Specific areas of ongoing research in the Sepulveda laboratory include:

Genomics and mechanisms of esophageal and gastric adenocarcinoma, pre-cancer lesions and Barrett’s esophagus:

     -Defining, characterizing and validating genomic, RNA and protein biomarkers to identify patients with Barrett’s esophagus with risk of progression to dysplasia and adenocarcinoma.

     -In vivo and in vitro models of gastric and esophageal cancers, including disease specific organoids and mouse models for chemoprevention of dysplasia and cancer.

     -Genome wide and transcriptomic analyses of pre-cancer and cancer lesions using next generation sequencing (NGS), gene expression microarrays, and single cell RNAseq techniques.

Immune microenvironment of esophageal and gastrointestinal tract (esophageal, gastric and colorectal) pre-cancer and cancer lesions and immunotherapy biomarkers 

     -Characterization of immune microenvironment with multiplex quantitative immunofluorescence (qMIF) and digital pathology applications.

     -Transcriptomic analysis and biomarker validations in tissue microarrays.

Genomic and transcriptomic biomarkers of pre-cancer and cancers

     -Novel biomarker characterization for actionable mutations, transcript fusions, and genomic alterations for precision therapies