Jacksonville, Florida


Kasi.Pashtoon@mayo.edu Clinical Profile


The research interests of Pashtoon M. Kasi, M.D., are in gastrointestinal cancers with a recent primary focus on colorectal cancers.

Focus area

  • Colorectal cancers. With help from the Norma Lee and Morton Funger Clinician Career Development Award in Colon Cancer Research, Dr. Kasi is focused on the establishment and molecular characterization of a patient-derived colorectal cancer tissue registry. This has allowed for the development of avatars or mouse models (xenografts) and cell lines for patients. Dr. Kasi's laboratory mentor for this effort is John A. Copland III, Ph.D. Additionally, Axel Grothey, M.D. has been instrumental in shaping Dr. Kasi's career.
  • BRCA-related pancreas cancers. Dr. Kasi works with the Mayo Clinic Pancreatic Cancer SPORE on patients with BRCA-related pancreas cancers. This work has included compiling treatment outcomes in patients with BRCA and other homologous recombination (HR) pathway-related tumors. This has formed the basis for development of novel clinical trials incorporating the novel class of drugs called PARP inhibitors. Robert R. McWilliams, M.D. has been Dr. Kasi's primary mentor for this research.
  • Liquid biopsies — circulating tumor DNA (ctDNA testing). Dr. Kasi has been able to integrate this groundbreaking area of research into standard care for the patients he treats with gastrointestinal cancers. This has allowed for rapid, dynamic and noninvasive identification of mutational changes in a particular patient's tumor, allowing for therapy to be individualized as the tumor evolves. Clinical trials incorporating liquid biopsy platforms are under development as an outcome from these efforts.
  • Pharmacogenomics. Dr. Kasi and colleagues are not only incorporating tumor-related genetic aberrations into consideration for the patients they treat but also for pharmacogenomics to limit potential toxicities. This further helps personalize their care. Key collaborations in this field have been with ONEOME and Mayo Clinic's Center for Individualized Medicine.
  • Clinical trials. To help provide the most novel and precision-based therapies, development and activation of clinical trials in a timely fashion is crucial. At Mayo Clinic, Dr. Kasi has been able to offer and participate in trials for patients with GI cancers to align with Mayo's goal of being a destination cancer center.

Significance to patient care

Dr. Kasi's research findings allow him to personalize patient care and deliver the promise of precision medicine at multiple levels: considering a patient's genes (pharmacogenomics and germline genetics) when determining treatment; tumor-based genetic testing; and liquid biopsies (cell-free circulating tumor DNA).

Concurrently, work in the lab on cell lines and xenografts serves as a discovery platform for the development of novel drugs and drug combinations. These innovations can then be brought back to the clinic in the shape of clinical trials to serve the unmet need for novel therapeutics that are not only effective but also durable.

Professional highlights

  • Editor, Impact of Circulating Tumor DNA (ctDNA) in Patients with Gastrointestinal Malignancies, Research Topic, 2017-present
  • Recipient, Presidential Award, Best Young Research Scholar, Higher Education Commission, Pakistan, 2011
  • Recipient, Humanism and Excellence in Teaching Award, Arnold P. Gold Foundation, 2011
  • Author, Research: What, Why and How? A Treatise from Researchers to Researchers, AuthorHouse, 2009


See my publications


Academic Rank

  1. Assistant Professor of Oncology
  2. Assistant Professor of Medicine


  1. BASIC SCIENCE MASTERS Clinical and Translational Science, Programs, Mayo Graduate School, Mayo Clinic College of Medicine
  2. Fellow Hematology/Oncology, Programs in Rochester, Mayo School of Graduate Medical Education, Mayo Clinic College of Medicine
  3. Residency - Internal Medicine University of Pittsburgh
  4. Other - Non-Degree student Institute for Clinical Research and Education (ICRE); completed 9 credit courses through the International Scholars Program. University of Pittsburgh
  5. Internship - General Surgery University of Texas Health Science Center at San Antonio, TX

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