Board Certified Pathologists
Summit Pathology is an independent pathology laboratory, owned by a practice of sixteen board certified pathologists serving hospital systems and physician offices in Colorado, Wyoming, and Nebraska.
Ross Barner, MD
Dr. Barner is board certified in Anatomic and Clinical Pathology with extensive subspecialty experience in gynecologic and breast pathology. Dr. Barner is a well-rounded, customer service oriented general surgical pathologist who has authored numerous articles and abstracts. He has presented at nationally attended meetings and is active in several local and national pathology organizations.
Dr. Barner earned his Bachelor of Science degree from Washington State University and completed medical school at the Uniformed Services University in Bethesda, MD. Following medical school, Dr. Barner served twenty one years in the US Army including assignments as a Transitional Intern at Fitzsimmons Army Medical Center in Aurora, CO; flight surgeon at Hunter Army Air Field in Savannah, GA; Anatomic and Clinical Pathology resident at Walter Reed Army Medical Center in Washington, DC; Chief of Clinical Pathology at 121st General Hospital in Seoul, Korea; staff pathologist and interim Chair of the Department of Gynecologic and Breast Pathology at the Armed Forces Institute of Pathology; and six years as the National Capital Consortium’s pathology residency program director, Walter Reed Army Medical Center and National Naval Medical Center in Washington, DC. Dr. Barner left the Army as a Colonel following his last assignment as Anatomic Pathology Service Chief, Walter Reed National Military Medical Center, Bethesda, MD.
Richard Halbert, MD
Dr. Halbert is board certified in Anatomic and Clinical Pathology with subspecialty board certification in Hematopathology. He has special interest in general surgical pathology, dermatopathology, hematopathology and coagulation, and blood bank and transfusion medicine.
Dr. Halbert is a Colorado native and a graduate of the University of Colorado for both his undergraduate and medical degrees. He was elected to the Alpha Omega Alpha Medical Honor Society while at CU. His internship and pathology residency were both performed at the Naval Medical Center in San Diego, CA. Dr. Halbert served in the United States Navy for eight years. Since leaving the military, he enjoyed faculty appointments at the University of California, San Diego and Creighton University prior to returning to Colorado in 1998.
Jennifer Leidy, MD
Dr. Leidy is board certified in Anatomic and Clinical Pathology. She received her undergraduate degree from Northwestern University in Evanston, Illinois and attended medical school at West Virginia University School of Medicine in Morgantown, West Virginia.
Dr. Leidy completed her residency at the University of Massachusetts Medical School in Worcester, Massachusetts. She went on to complete her fellowship in Breast and Gynecologic Pathology at Magee Women’s Hospital of UPMC in Pittsburgh, Pennsylvania. Dr. Leidy is a member of the United States and Canadian Academy of Pathology.
Catherine Salisbury, MD
Dr. Catherine Salisbury is board cerified in Anatomic and Clinical Pathology as well as Dermatopathology. She completed her undergraduate degree at the University of Arkansas-Fayetteville and her medical degree at the University of Arkansas for Medical Sciences. Dr. Salisbury was a resident at Emory University in Atlanta, Georgia, and completed her fellowship in Dermatopathology, also at Emory University.
Dr. Salisbury is a member of the College of American Pathologists and the United States and Canadian Academy of Pathology. Before joining Summit Pathology, Dr. Salisbury served as partner and president of Pathologists of Kitsap County in Silverdale, Washington.
Christopher Bee, MD
Dr. Bee is board certified in Anatomic and Clinical Pathology as well as in Hematopathology. He is currently the Laboratory Medical Director at Poudre Valley Hospital and Medical Center of the Rockies. Dr. Bee has authored several articles and given lectures, nationally and locally, on the uses of flow cytometry in diagnosing disease, and is an active member of several national pathology organizations, most notably the College of American Pathologists (CAP). Dr. Bee is a past member of the CAP Diagnostic Immunology Resource and Professional Affairs Committee and currently serves on the Economic Affairs Committee and the Policy Roundtable Committee. Dr. Bee also serves as the Colorado Delegate Chair for the CAP House of Delegates, and is a past President of the Colorado Society of Clinical Pathologists. His areas of interest and expertise include general surgical pathology, head and neck pathology, and all aspects of hematopathology with an emphasis on flow cytometry.
Dr. Bee graduated from McKendree University in Lebanon, Illinois in 1989 with a Bachelor of Science degree in Biology, where he was also an Academic All-American in soccer. He then completed medical school, Anatomic and Clinical Pathology residency and Hematopathology fellowship at The Saint Louis University School of Medicine. He moved to Colorado in 2003 after serving four years in the United States Air Force as a staff pathologist and as the medical director of flow cytometry at Wilford Hall Medical Center in San Antonio, TX.
H. Wentzell Hamner, MD
Dr. Hamner serves at Managing Partner of Summit Pathology and Medical Director of the Harmony Surgery Center, Sterling Regional Medical Center, Centers for Gastroenterology and Gastroenterology of the Rockies. Dr. Hamner is board certified in Anatomic and Clinical Pathology and is the group’s expert consultant in gastrointestinal pathology. He also has special interest and expertise in general surgical pathology and microbiology. Dr. Hamner holds memberships in numerous local and national pathology organizations.
Dr. Hamner earned his Bachelor of Arts degree from the University of the South in Sewanee, TN, and is a proud graduate of the University of Tennessee College of Medicine. He performed his anatomic and clinical pathology training at Baylor College of Medicine in Houston, TX. Following his residency, he enjoyed a two year gastrointestinal pathology fellowship under the tutelage of the late Rodger C. Haggitt at the University of Washington in Seattle, WA.
Arlene Libby, MD
Dr. Libby is a diplomate of the American Board of Pathology in Anatomic and Clinical Pathology and holds subspecialty board certification in Cytopathology as well. Dr. Libby is Medical Director of Summit Pathology Laboratories Cytology and Molecular Services, and the Long-Term Acute Care Hospital. She is one of the group’s expert consultants for breast pathology and gynecologic pathology. She is also the group’s only cytopathologist. She has published numerous articles and abstracts in peer reviewed pathology journals on these topics.
Dr. Libby received her Bachelor of Science degree Summa Cum Laude at Oral Roberts University in Tulsa, OK. She remained in Tulsa for her medical studies, graduating from the University of Oklahoma School of Medicine. She performed her Anatomic and Clinical Pathology residency at Wilford Hall Medical Center in San Antonio, TX. Dr. Libby has successfully completed three post-graduate fellowship programs in surgical pathology (at Wilford Hall Medical Center), cytopathology (also at Wilford Hall) and breast pathology (at the University of Texas Health Science Center, San Antonio, TX). She moved to northern Colorado from Greensboro, NC, where she practiced with Greensboro Pathology Associates.
Jakub Stefka, MD
Dr. Stefka is board certified in Anatomic and Clinical Pathology, as well as Hematology. He is the laboratory Medical Director at VA Medical Center in Cheyenne, Wyoming, Platte County Memorial Hospital in Wheatland, Wyoming and Kimball Health Services, Kimball, Nebraska. Dr. Stefka completed his medical education at Palacky University in Olomouc, Czech Republic. He completed a residency in Internal Medicine at the Institute of Allergy and Clinical Immunology, Faculty Hosptial, also in Olomouc. Dr. Stefka completed an internship at Rush University Medical Center in Chicago, Illinos before becoming a resident in pathology at University of Colorado Health Sciences Center in Denver, Colorado. He also completed a fellowship in surgical pathology at University of Colorado, and a fellowship in hematopathology at the University of Utah, Salt Lake City, Utah. Previously, Dr. Stefka served as a pathologist with Anapath Diagnostics in Cheyenne, Wyoming. Anapath Diagnostics became Summit Pathology in 2015.
Cory Dunn, MD
Dr. Dunn has recently been appointed as laboratory section chief at the UC Health South: Memorial Hospital System in Colorado Springs. Prior to this he served for many years as Chairman of the Department of Pathology at North Colorado Medical Center laboratory, as Medical Director at East Morgan County Hospital Laboratory and Colorado Plains Medical Center laboratory, Dr. Dunn is board certified in Anatomic and Clinical Pathology as well as Hematopathology. He has special interests and expertise in hematopathology (including flow cytometry) and pioneered medical directorship of the molecular lab at NCMC. Dr. Dunn has published numerous papers in peer-reviewed journals on various topics in hematopathology, urologic pathology and toxicology. He has also presented numerous abstracts in platform presentations at national hematopathology and molecular pathology meetings.
Dr. Dunn attended Idaho State University earning his MD from the Saint Louis University School of Medicine. Following a stint as a general medical officer in the United States Air Force, his Anatomic and Clinical Pathology residency was at Wilford Hall Medical Center in San Antonio, TX. Dr. Dunn’s Hematopathology fellowship was under the tutelage of Dr. Peter Banks at the University of Texas Health Science Center in San Antonio. He joined Summit Pathology after directing Immunology and Molecular Diagnostics at Wilford Hall Medical Center Laboratory
Charlene Hellman, MD
Dr. Hellman is board certified in Anatomic and Clinical Pathology , Hematopathology, and Molecular Genetic Pathology. She is a member of the Unites States and Canadian Academy of Pathology, the American Society for Clinical Pathology, the College of American Pathologists, and the Association for Molecular Pathology. She has presented several abstract publications and lectures on various genetic topics such as the genetics of warfarin susceptibility, and authored an article on early T cell precursor leukemia.
Dr. Hellman received her Bachelor of Science from the University of California, Los Angeles and her Medical Doctorate from Louisiana State University in New Orleans. Dr. Hellman then completed her Anatomic and Clinical Pathology residency at the University of New Mexico, Albuquerque and went on to fellowships in Molecular Genetic Pathology and Hematopathology at the University of Pittsburgh Medical Center.
Craig Nerby, MD
Dr. Nerby is board certified in Anatomic and Clinical pathology. He is a member of the American Society for Clinical Pathology and the College of American Pathologists. Dr. Nerby has authored several articles and abstracts and has taught pathology residents at both the Mayo Clinic and several Uniformed Services Health locations.
Dr. Nerby received his Bachelor of Arts degree from Moorhead State University in Moorhead, Minnesota, and attended Medical School at Wayne State University School of Medicine in Detroit, Michigan. His residency was completed at the University of Nebraska Medical Center, where he served as Chief Resident. Dr. Nerby’s fellowship in Surgical Pathology was completed at the Mayo clinic. Dr. Nerby was a staff pathologist at both Wilford Hall Medical Center and Brook Army Medical Center before arriving at Summit Pathology.
Michael Walts, MD
Dr. Walts is board certified in Anatomic and Clinical Pathology. He is the Medical Director of Horizon Laboratories, Greeley Medical Clinic Laboratory (MCR), Greeley Oncology Laboratory (MCR), Greeley Emergency and Surgery Center laboratory (UCH) and Physician Director of Summit Pathology Outreach Services. He is the Medical Director of the Garth Englund Blood Donor Centers at Poudre Valley Hospital and Medical Center of the Rockies. In addition, he is the Medical Director of transfusion services at McKee Medical Center, Medical Center of the Rockies and Poudre Valley Hospital. He has special interest and expertise in general surgical pathology, gastrointestinal pathology and transfusion medicine. Dr. Walts is a member of several national pathology organizations and has published articles in peer reviewed journals on topics in breast pathology and cervical pathology.
Dr. Walts grew up in northern Colorado and earned his Bachelor of Science Degree from The Colorado College in Colorado Springs, CO. He completed medical school at the Uniformed Services University School of Medicine in Bethesda, MD. His Anatomic and Clinical Pathology residency was performed at the National Capital Consortium, a joint residency program between Walter Reed Army Medical Center and the National Naval Medical Center. Dr. Walts left the army as a Lieutenant Colonel, after serving at Madigan Army Medical Center in Tacoma, WA, and Evans Army Community Hospital at Fort Carson, CO, where he was chief of the Pathology Department.
Phil Haberman, MD
Dr. Haberman is board certified in Anatomic and Clinical Pathology, with additional certification in Cytopathology. Dr. Haberman graduated from Chadron State College in Chadron Nebraska before attending medical school at the University of Nebraska Medical Center in Omaha, Nebraska. He completed his internship and residency also at the University of Nebraska Medical Center.
After his residency, Dr. Haberman has been in private practice for 22 years serving in a variety of roles including director of a Fine Needle Aspiration Service, hospital committee chairmanships, hospital board member, board member of a number of health care organizations, laboratory medical directorships, and most recently as laboratory medical director at Cheyenne Regional Medical Center in Cheyenne Wyoming, and as President and Medical Director of AnaPath Diagnostics also in Cheyenne, WY. AnaPath Diagnostics became part of Summit Pathology in 2015.
Nathan Johnston, DO
Dr. Johnston is board certified in Anatomic and Clinical Pathology. He currently serves as the Medical Director of the blood bank services at both Memorial Hospital locations in Colorado Springs. He has special interest in surgical pathology, gastrointestinal and hepatic pathology and transfusion medicine.
Dr. Johnston received his undergraduate degree from Brigham Young University in Provo, Utah, and went on to medical school at Kirksville College of Osteopathic Medicine in Kirksville, Missouri. He completed a fellowship in pathology at the University of Missouri, Columbia and his residency at Baylor College of Medicine in Houston, Texas. Dr. Johnston served as a staff pathologist at Wilford Hall Medical Center and Brooke Army Medical Center in San Antonio, Texas, where he instructed residents and served as the Assistant then Acting Medical Director of the Blood Donor Center and Transfusion Services (at WHMC). He achieved the rank of Captain in the United States Air Force. Before joining Summit Pathology, Dr. Johnston served as a pathologist in Tucson, AZ at Northwest Medical Center and Oro Valley Hospital, serving as the medical director at latter. He is a fellow of the College of American Pathologists and the American Society for Clinical Pathology.
Carrie Pizzi, MD
Dr. Pizzi is board certified in Anatomic and Clinical Pathology and has additional training in Breast and Gynecological Pathology. She is a member of the College of American Pathologists and the United States and Canadian Academy of Pathology. Dr. Pizzi has authored several articles, including the study of Molecular Pathogenesis of Hereditary Ovarian Carcinoma.
Dr. Pizzi received her Bachelor of Science degree in Molecular Biology from Princeton University in Princeton, NJ graduating Phi Beta Kappa. She attended medical school at Duke University graduating Alpha Omega Alpha and completed her residency in Anatomic and Clinical pathology at the University of Washington Medical Center in Seattle, WA. Dr. Pizzi also completed a fellowship in Breast and Gynecological Pathology at the University of Washington.
Heath Worcester, MD
Dr. Worcester is board certified in Anatomic and Clinical Pathology. He holds additional board certification in Dermatopathology and Hematopathology. Dr. Worcester received his Bachelor of Science degree in Biology from Ohio University. He attended medical school at the University of Toledo School of Medicine and then completed a residency in Anatomic and Clinical Pathology at Emory University in Atlanta, Georgia. Dr. Worcester completed a fellowship in Hematopathology at the University of New Mexico under the direction of Dr. Kathryn Foucar and a second fellowship in Dermatopathology at Emory University under the direction of Dr. Douglas Parker. He has authored several articles in general anatomic pathology, hematopathology, pediatric pathology and dermatopathology.