Our Team
The exceptional team and faculty members that lead our APP Hematology/Oncology Fellowship program share a passion for teaching and clinical education. They mentor and guide our fellows to provide them with a comprehensive education and the tools they need to practice Hematology/Oncology.
We aim to build a supportive culture where APPs transition into confident, autonomous providers who are leaders in quality and comprehensive hematology/oncology care. Through innovative education, practice-based learning and evidence-based practice, our program cultivates APPs who are deeply connected to the people they serve and driven to improve health outcomes.
Kristina Diaz, M.D.
Designated Institutional Official
Kristina Diaz, MD, serves as President of Onvida Health’s Medical Group where she leads the group’s collaborative vision while advocating for nearly 400 physicians and advanced practice providers who represent more than 35 ambulatory clinics. Dr. Diaz began her leadership career in 2014 as the Associate Program Director of the Onvida Health’s Family and Community Medicine Residency Program. In that role, she elevated the program nationally, while also expanding her professional scope and oversight. Dr. Diaz then served as Executive Medical Director of Primary Care, Chief Academic Officer and Program Director of the Family Medicine Residency Program.
Raised in Yuma, Dr. Diaz has a true passion for local healthcare and understands the impact on the community. A graduate of Yuma High School, she went on to earn her undergraduate degree at the University of Arizona and her medical degree from Ross University School of Medicine. She completed her Family Medicine Residency at the University of Kansas Medical Center and was appointed chief resident of her class.
In 2025, Dr. Diaz was selected as a fellow in the Carol Emmott Fellowship. This competitive and nationally recognized program empowers women healthcare leaders with mentorship, resources, and opportunities to drive change in their organizations and communities. In 2023, Dr. Diaz served as President of both the Arizona Academy of Family Physicians and the Association of Family Medicine Residency Directors. Dr. Diaz was also selected as Yuma County Chamber of Commerce’s 2022 Athena Award recipient. The Athena Award recognizes women who have achieved the highest level of professional excellence while dedicating their lives to community and family.
Margery Smith, D.N.P., F.N.P-C
Program Director – APP Hematology/Oncology Fellowship
Margery serves as the Program Director for the Advanced Practice Professional (APP) Hematology/Oncology Fellowship at Onvida Health, bringing over a decade of hands-on clinical and leadership experience to this role. Margery began her healthcare journey in 2012, advancing through multiple nursing roles and earned her Doctor of Nursing Practice degree from Frontier Nursing University. She has served as a Family Nurse Practitioner since 2021 at the Transitional Care Clinic and the Inpatient Behavioral Health Unit at Onvida Health.
Her commitment to education and quality improvement is evident in her robust preceptorship and mentorship of a diverse group of learners including registered nurses, nurse practitioners, physician assistants, resident physicians and PharmD residents. As a primary preceptor for the PharmD residents, she works closely with two residents annually, helping to guide their learning goals and provide dedicated mentorship.
Her dedication to mentorship and innovation has earned her multiple honors including completion of the 2025 cohort of the AzHHA Healthcare Leadership Academy, published author in The Joint Commission Journal on Quality and Patient Safety (2025), nominations for the Excellence in Nursing Mentorship Award for Yuma County (2024, 2025), recipient of the Foundation of Onvida Health Webb Nursing Scholarship (2024), and the Quality Improvement Award from Southwest Arizona Regional Grand Rounds (2024). She also spearheaded various A3 process improvement projects at Onvida Health since 2017, aimed at enhancing care delivery across the organization.
As Program Director, Margery brings heart, vision and a deep commitment to evidence-based, interprofessional collaboration, and the cultivation of clinical excellence among APPs fellows.
Abhinav Chandra, M.D., M.Sc., F.A.C.P., M.B.A.
Faculty
Dr. Abhinav Chandra is the Vice President of Specialty Care Services at Onvida Health. He serves as the Medical Director of the Onvida Health Cancer and Blood Disorder Center and Director of Institutional Research for Onvida Health. He holds the rank of Assistant Professor of Medicine, New York Medical College. He completed his MBA from UCLA Anderson School of management in 2021. He is also the Chair of Treatment Steering Committee, Arizona Cancer Coalition, and Arizona Department of Health Services. Dr. Abhinav Chandra received the Visionary Leadership award (2025) and has more than 30 peer-reviewed publications with over 2000 citations, 3 book chapters and over 60 posters presented in national and international conferences. As the Principal Investigator for his site for more than 30 industry sponsored and population health based clinical studies, Dr. Chandra has expanded innovative treatments and has led to the transformation of cancer care in Yuma. His areas of interest include evaluating the role of AI/ML in healthcare, health care disparity and health services research
Bridgett Allen, D.N.P., F.N.P-C, A.O.C.N.P.
Faculty
Bridgett has been a hematology/oncology nurse practitioner at Onvida Health Cancer and Blood Disorder Center since 2017. She is also involved in the Institutional Research Department at Onvida Health, having served as the Sub-Investigator on multiple clinical trials. After working as an RN for over 10 years, she completed her Masters in Nursing and Nurse Practitioner Certification through AANP in 2013. She completed a Post-Masters Certification in Nursing Education in 2015, an Advanced Oncology NP certification in 2018 and her DNP in 2021. She was a preceptor to many NP students during her four years working in Family Practice. Her areas of interest include hematology, oncology and clinical research. She hopes to complete her PhD in the coming years and be a strong contributor to improved cancer care through EBP.
Carrie Lopez, D.N.P., F.N.P-C, A.O.C.N.P.
Faculty
Carrie Lopez is a board-certified Advanced Oncology Certified Nurse Practitioner (AOCNP) with a Doctor of Nursing Practice from the University of Arizona. Specializing in hematology and oncology, Carrie focuses on breast cancer, solid malignancies, cancer survivorship, and palliative care. With a deep commitment to patient-centered care, Carrie believes in using a comprehensive, multidisciplinary approach to educate, support, and treat patients and their families throughout their cancer journeys.
In addition to clinical practice, she actively contributes to support initiatives as a member of the Peer Support Team, APP Medical Staff, and the Bioethics Committee. Her goal is to help patients achieve optimal health outcomes and an improved quality of life at every stage of care.
Sarah Thompson, M.S.N., F.N.P-C
Faculty
Sarah Thompson has been with the hematology/oncology team at Onvida Health and Blood Disorders Center since 2024. She works alongside the medical oncologists/hematologist’s and radiation oncologist to provide care to our patients. Her primary focus is benign hematology and lung cancer. She is a member of the Onvida medical group’s peer support program where she has training in providing peer to peer support to fellow MD’s and APP’s. Prior to becoming an NP, Sarah worked as an emergency room nurse for 9 years, finishing her master’s in nursing and Nurse Practitioner certification in December of 2023. She continues to grow and learn in the field of oncology and hematology with the goal of contributing even more to the team’s successes.
When she is not focused on cancer care she enjoys spending time with her family, watching movies, scuba diving, and taking naps.
Hannah Ponder, M.B.A., C-T.A.G.M.E.
Administrative Director, Medical Education
Hannah Ponder is the Administrative Director of Medical Education at Onvida Health – Yuma Medical Center, where she oversees Graduate, Undergraduate, and Continuing Medical Education programs. With nearly a decade of experience in academic medicine, she brings expertise in accreditation, compliance, and operational leadership, supporting the successful expansion and optimization of residency and fellowship programs.
Hannah is known for her strategic thinking, team development, and process improvement, backed by certifications in TAGME, Lean, and a Project Management–focused MBA. She has led institutional audits, built onboarding and evaluation systems, and served as a trusted liaison to C-Suite leadership, program directors, and medical school affiliates. Her ability to lead through growth and change has resulted in sustained programmatic excellence.
As Immediate Past-President of the Association of Family Medicine Administration (AFMA) and a frequent national presenter, Hannah is a vocal advocate for the role of medical education in strengthening the healthcare workforce. She is passionate about building strong training environments that elevate both medical education and patient care—believing that when training programs thrive, communities thrive.
Nohemi Ortega
Graduate Medical Education Coordinator
Dedicated program administrator with over 20 years of experience leading and coordinating health, education and community-based programs. Throughout her career, Nohemi has built a reputation for excellence in organization, stakeholder collaboration, and culturally competent service delivery. Nohemi has led large-scale health and education initiatives with state, tribal and nonprofit organizations, developing programs that promote equitable access to care and education. With a deep commitment to fostering excellence, Nohemi is dedicated to supporting residents/fellows, faculty, and programs that cultivate the next generation of skilled and compassionate APPs and physicians. Originally from Sonora Mexico, Nohemi has made her home in Yuma.
Outside of work she enjoys spending time with her family, cooking traditional meals, and taking long walks.
