Our Team


Stephen G. Diamantoni, M.D.

Dr. Diamantoni is a graduate of Lehigh University and Hahnemann Medical College. He completed his residency training in Family Practice at Lancaster General Hospital in 1985, where he served as Chief Resident. Dr Diamantoni is board certified in Family Practice and has also earned Board Certification in Geriatrics and Sports Medicine. He is Board Certified by the American Board of Medicolegal Death Investigators. He is a Fellow of the American Academy of Family Practice. Dr Diamantoni founded Diamantoni and Associates in 1985 and is the Managing Partner. He is the elected Coroner of Lancaster County. He lives in Manheim Township with his 3 children. He enjoys skiing, scuba diving, and coaching soccer.

Office Locations:

Howard J. Gerstein, M.D.

Dr. Howard Gerstein has been a Pennsylvania boy all his life, graduating from Hazelton High School, Muhlenberg College and Pennsylvania State Medical School. He served in the Navy for seven years, including tours in Argentina, Newfoundland Canada, and in Cherry Point, NC. Dr. Gerstein performed his internship and family practice residency while with the Navy in Charleston, SC.

Dr. Gerstein was initially board certified in Family Practice in 1989 and joined Diamantoni & Associates in 1990. He has hospital privileges at Lancaster Regional Medical Center as well as at Lancaster General Hospital where he was Chairman of the Department of Family Practice from 2009 through 2011.

Dr. Gerstein enjoys studying the Bible and riding his bicycle with the Lancaster Bicycle Club. He considers himself a “car guy/gear head” having raced cars for 17 years. A proud grandfather, he hopes his two-year old grandson, Eli, will drive his 1956 hot-rod Chevrolet station wagon when he gets his driver’s license.

Office Locations:

William R. Vollmar, M.D.

William Vollmar attended the University of Maryland in Baltimore County and graduated with a Bachelor of Arts. He attended the Medical College of Virginia and received his Doctor of Medicine degree. Dr. Vollmar completed his residency with Lancaster General Hospital Family and Community Medicine before joining Diamantoni & Associates in 1992.

Dr. Vollmar was board certified by the American Board of Sports Medicine in 1997 and in 2007. He was board certified by the American Board of Family Medicine in 1992, 1997, and in 2005. He is an active member of American Academy of Family Physicians, Pennsylvania Academy of Family Physicians, American College of Sports Medicine and American Medical Society for Sports Medicine.

Office Locations:

Associate Doctors (listed alphabetically)

Gail F. Bodner, M.D.

Dr. Gail Bodner graduated from Rutgers University with a Bachelor of Science degree in Biochemistry. She received her medical degree from Hahnemann University in Philadelphia and completed her Family Medicine internship at Eastern Virginia Medical School. Dr. Bodner performed her Family Medicine residency at Moses Cone Memorial Hospital in North Carolina.

After working in emergency medicine at Winona Memorial Hospital in Indianapolis, IN Dr. Bodner continued in this field at both Lancaster General Hospital and Reading Hospital and Medical Center. Dr. Bodner joined Diamantoni and Associates in 1989 and is a member of the American Academy of Family Physicians and the Pennsylvania Medical Society. She enjoys treating patients of all ages and considers it a privilege to work with patients and their families.

Office Locations:

Adrian F. Hazbun, M.D.

Dr. Adrian Hazbun attended Yale University where he received a double Bachelor of Science degree in molecular biophysics, biochemistry, and organismal biology. He attended Temple University School of Medicine and graduated in 2002. Dr. Hazbun performed his Family Medicine internship and Family Medicine residency at Ventura County Medical Center in Ventura, California, graduating in 2005.

After travelling to Botswana, Uganda, and Tanzania where he treated children suffering from HIV/AIDS, Dr. Hazbun joined Diamantoni & Associates team in 2008. He is certified by the American Board of Family Medicine and his interests include playing soccer and traveling overseas.

Office Locations:


Maria F. Perlis, M.D.

Dr. Maria Perlis was born and raised in Schenectady, NY. She attended Cornell University for her undergraduate studies, receiving her degree in 1990. Dr. Perlis earned her medical degree in 1994 from the State University of New York Health Science Center. She performed her residency at Lancaster General Hospital from 1994-1997 and joined Diamantoni & Associates in August of 1997.

Dr. Perlis has been board certified by the American Board of Family Medicine since 1997, and is currently certified through 2023. Professional memberships include: the American Academy of Family Physicians, the Pennsylvania Academy of Family Physicians, and the Christian Medical and Dental Associates.

Office Locations:

Jeffrey T. Trost, M.D.

Dr. Jeffrey Trost attended the University of Scranton and received a Bachelor of Science in Biology before attending Temple University for his Doctor of Medicine degree. He completed his residency at Lancaster General Hospital and joined Diamantoni & Associates in 1994.

Dr. Trost enjoys caring for patients of all ages. He feels it is an honor to be a part of so many peoples’ lives and hopes to assist them in their journey.

Dr. Trost has retired from rugby, but still enjoys hockey, skiing and kayaking, making his yard look half-decent, and going to the beach with his wife and dogs.

Office Locations:

Joyce A. Vafeas, M.D.

Dr. Joyce Vafeas graduated from Franklin and Marshall College with a Bachelor of Arts in Chemistry. She received a Master of Science degree in Medicinal Chemistry from Philadelphia College of Pharmacy and Science. She then received her medical degree from Temple University and completed her residency in Family and Community Medicine at Lancaster General Hospital. Dr. Vafeas has been practicing in Lancaster County since then and joined Diamantoni and Associates Family Practice in 2007. She is Board Certified by the American Board of Family Practice and is a member of the following: American, Pennsylvania, and Lancaster County Academies of Family Physicians, the Pennsylvania Medical Society, and the Lancaster City and County Medical Society.

Dr. Vafeas enjoys Family Practice because she can establish a relationship with her patients and take care of them through the years. Her goal is to help her patients be as healthy as they can be, both mentally and physically.

Office Locations:

Physician Assistants (listed alphabetically)

James Bounds, PA-C

After graduating from Conestoga Valley High School, James Bounds went to the University of Richmond where he earned his Bachelor of Science and Bachelor of Arts degrees in 2001. After spending time working and playing in Key West, FL and Portland, OR, James completed his Master of Health Sciences in Physician Assistant Studies at Lock Haven University of Pennsylvania in 2006. He is certified by the National Commission of Certification of Physician Assistants.

James and his wife have three children who are the focus and joy of their lives. If not at home with the kids, you will most likely find James enjoying the outdoors on his skis, bicycle, or with golf clubs or a flying fishing rod in hand.

Office Locations:

Cynthina Brubaker, PA-C

Cynthia Brubaker received her registered nursing degree at St. Joseph Hospital, now known as Lancaster Regional Hospital School of Nursing in Lancaster, PA. She then attended Pennsylvania State University Physician Assistant Program where she received an Associate Degree in Clinical Health Services.

Office Locations:

Melinda Rudy, PA-C

Melinda Rudy PA-C attended Lock Haven University for both her undergraduate and graduate degree. She participated in an accelerated 3+2 program and received her Bachelor’s degree in Health Science and Master’s Degree in Health Science. While in PA school she did a clinical rotation with Diamantoni and Associates and then joined the practice in the summer of 2015. In addition to Family Medicine, Melinda also practices sports medicine as part of the Primary Care Sports Medicine group and takes care of athletes at Peque Valley High School.

In her spare time, she likes to plot new pranks to pull on Dr. Ankur Sadhukhan.

Office Locations:

Sarah Saxon, PA-C

Sarah Saxon is a 2016 graduate of Arcadia University where she earned her Master of Medical Science in Physician Assistant Studies. She completed her undergraduate degree at Towson University, earning a Bachelor of Science in Biology. Sarah enjoys traveling and has studied abroad in England and Costa Rica. She also participated in a service trip to Nicaragua where she and her classmates provided medical care and public health services to under-served communities. Sarah is accredited by the National Commission on Certification of Physician Assistants and is a member of the American Association of Physician Assistants as well as the Pennsylvania Society of Physician Assistants.

Office Locations:

Michael C. Shipman, PA-C

Michael Shipman earned his Bachelor of Science degree at Rutgers University. He attended the College of Medicine and Dentistry of New Jersey and received his Certificate of Training as a Physician’s Assistant. Michael earned his certification of training as a Medical Services Specialist and Medical Services Technician at the U.S. Air Force School of Health Sciences. Michael joined Diamantoni & Associates in 2008.

Office Locations:

Gregory Wright, PA-C

Greg Wright joined Diamantoni & Associates after completing his Master’s Degree in Health Science at Lock Haven University. Prior to Lock Haven, Greg attended Houghton College in Western New York where he majored in biology and played four years of intercollegiate soccer. Greg has played sports his entire life and has a particular interest in sports medicine and adolescent health. He thoroughly enjoys his responsibilities as the team medical provider at Lampeter-Strasburg High School and providing coverage for the Pennsylvania Interscholastic Athletic Association District Three and State Championships.

Greg has an active role as the Region Three Representative in the Pennsylvania Society of Physician Assistants. He is also an active member of the American College of Sports Medicine, American Academy of Physician Assistants, and Society of Physician Assistants in Clinical Ultrasound. He is certified as a physician assistant by the National Commission on Certification of Physician Assistants and is certified in Advanced Cardiac Life Support and Basic Life Support. Greg has also completed additional training in musculoskeletal ultrasound at Duke University School of Medicine.

When not working, Greg enjoys going on walks by the Susquehanna River with his wife and daughter, and running with his Labrador retriever, Lily.

Office Locations:


Daniel D’Elia, D.O.

Daniel D’ Elia was born in Philadelphia, PA but claims Lancaster as his home since he has lived here for 31 years. He graduated from Hope College in Holland, MI in 1977, then from Pennsylvania College of Optometry in 1982. Dr. D’ Elia is a member of Beta Sigma Kappa, the International Optometric Honor Society, and joined Diamantoni and Associates in 1999. In addition to his busy practice at Diamantoni and Associates, Dr. D’Elia also takes care of Alzheimer’s patients at Conestoga View.

Office Locations: