Jacksonville, Florida


Casler.John@mayo.edu Clinical Profile


The research interests of John D. Casler, M.D., center on head and neck tumors (neoplasms) and thyroid disorders. Dr. Casler has a keen interest in identifying factors that indicate more aggressive head and neck tumors to tailor treatment to optimize patient outcomes. He also has an interest in tissue banking and has participated in research to investigate the impact of pharmaceuticals on cell lines.

Dr. Casler's surgical practice is limited to care of patients with head and neck neoplasms and thyroid disorders. He has been practicing for more than 30 years and has worked in an integrated clinical research setting for much of that time. Dr. Casler has been the principal investigator for numerous research protocols seeking to optimize outcomes for patients with head and neck cancers.

Focus areas

  • Management of endocrine disorders in the head and neck; surgical care of the thyroid and parathyroid. Dr. Casler is engaged in numerous research projects related to thyroid and parathyroid problems, molecular investigation of thyroid cancers, and imaging techniques in hyperparathyroidism.
  • Management of benign and malignant tumors of the head and neck. Dr. Casler works to find better ways to treat patients with salivary tumors, throat (oropharyngeal and hypopharyngeal) tumors, and skin cancers (cutaneous malignancies) of the head and neck. He collaborates with basic scientists, endocrinologists, radiation experts, medical oncologists and other surgeons. Their research impacts treatment protocols and patient outcomes and includes open and robotic approaches to head and neck tumors.
  • Management of selected skull base tumors. Dr. Casler is involved in developing endoscopic approaches to pituitary gland and anterior skull base surgery.

Significance to patient care

Dr. Casler's head and neck and reconstructive surgery research is aimed at improving patient outcomes, including lower readmission rates, better quality of life, and higher rates of survival.


Primary Appointment

  1. Consultant, Department of Otolaryngology - Head & Neck Surgery/Audiology

Joint Appointment

  1. Consultant, Department of Neurosurgery

Academic Rank

  1. Associate Professor of Otolaryngology


  1. Fellow - Combined Head and Neck Surgery / Facial Plastic and Reconstructive Surgery with Columbia Presbyterian Hospital and St. Vincent's Hospitals St. Vincents Hospital and Medical Center
  2. Resident - Otolaryngology / Head & Neck Surgery Walter Reed Army Medical Center
  3. Internship - Transitional Walter Reed Army Medical Center
  4. MD George Washington University Medical School
  5. BA - Cum laude -Natural Sciences The Johns Hopkins University

Clinical Studies

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