Team

Sorin Petre, MD

Sorin Petre, MD is a gastroenterologist and board certified by the American Board of Medicine in Internal Medicine; Gastroenterology and Transplant Hepatology.

He graduated from Universitatae de Medicina si Farmacie Grigore T Popa, Lasi, Romania. Dr. Petre also completed his residency in Internal Medicine at Maricopa Integrated Health System in Phoenix, Arizona and his fellowship at the Mayo Clinic Hospital in Phoenix, AZ.

Shaun McGowan, PA-C

Shaun McGowan PA-C received his undergraduates and masters degree in Physician Assistant Studies at Duquesne University Pittsburgh, PA. Shaun specializes in the management of hepatology, benign anorectal diseases, and functional disorders. In his spare time, Shaun enjoys snowboarding, rock climbing, and spending time outside exploring his new home.

John Walker, MD, FACG

John Walker, MD, FACG is a gastroenterologist and board certified by the American Board of Medicine in Internal Medicine and Gastroenterology.

He graduated from University of Texas Health Science Center Southwestern Medical School, in Dallas, Texas. Dr. Walker completed his Fellowship in Gastroenterology at the University of Miami Affiliated Hospitals in Miami, Florida

In his spare time, Dr. Walker enjoys working out, hiking, traveling and spending time with his family and dogs.

Surin Vasdev, MD

Surin Vasdev, MD is a gastroenterologist and board certified by the American Board of Medicine in Gastroenterology.

He graduated from University of London and completed his Fellowship and Residency in Gastroenterology at the Mayo School of Medicine in Rochester, MN.

Dr. Vasdev practiced in the Corvallis area and has been an assistant professor at Western University of Health Sciences in Lebanon, OR. He joins Centennial Gastroenterology with multiple years in the field and is excited to explore Douglas County.

In his spare time, Dr. Vasdev enjoys painting, hiking, biking, and studying history.

Samantha B. Griffin, FNP-C

Samantha B. Griffin is a Family Nurse Practitioner with experience in Primary Care and Interventional Pain Management. She is additionally licensed as a registered nurse with twelve years of experience in Critical Care and Cardiac Medicine.

After graduating from Roseburg High School, she attended Oregon State University in Corvallis, Oregon, graduating with her Bachelor of Science in Exercise Sport Science and later obtained her Bachelor of Science in Nursing at the University of North Alabama. Samantha completed her Family Nurse Practitioner education at Saint Joseph’s College of Maine in 2016. Samantha is a current member of the American Association of Nurse Practitioners and the American Gastroenterological Association.

In her spare time, Samantha enjoys hiking, spending time with her family and gardening.