Advisory Committees

Mark J. Fesler, MD, is a hematology oncologist in his eleventh year as associate professor of internal medicine at Saint Louis University. He was formerly the director of the Blood and Marrow Transplant Program at SSM Saint Louis University hospital. He is a member of the American Society of Hematology and the American Society of Transplant and Cellular Therapy and has expertise in hematological malignancies including Hodgkin and non-Hodgkin lymphoma, multiple myeloma, acute myeloid leukemia, acute lymphoblastic leukemia, chronic lymphocytic leukemia, chronic myeloid leukemia, and myelodysplastic syndrome. 

Dr. Fesler earned a medical degree from Saint Louis University School of Medicine, followed by internal medicine residency at the University of Colorado Health Sciences Center, where he was chief resident in his final year. He completed a fellowship in hematology and oncology at Saint Louis University School of Medicine and is board-certified in both hematology and medical oncology. 

Mark J. Fesler, MD, is a hematology oncologist in his eleventh year as associate professor of internal medicine at Saint Louis University. He was formerly the director of the Blood and Marrow Transplant Program at SSM Saint Louis University hospital. He is a member of the American Society of Hematology and the American Society of Transplant and Cellular Therapy and has expertise in hematological malignancies including Hodgkin and non-Hodgkin lymphoma, multiple myeloma, acute myeloid leukemia, acute lymphoblastic leukemia, chronic lymphocytic leukemia, chronic myeloid leukemia, and myelodysplastic syndrome. 

Dr. Fesler earned a medical degree from Saint Louis University School of Medicine, followed by internal medicine residency at the University of Colorado Health Sciences Center, where he was chief resident in his final year. He completed a fellowship in hematology and oncology at Saint Louis University School of Medicine and is board-certified in both hematology and medical oncology. 

Mark J. Fesler, MD, is a hematology oncologist in his eleventh year as associate professor of internal medicine at Saint Louis University. He was formerly the director of the Blood and Marrow Transplant Program at SSM Saint Louis University hospital. He is a member of the American Society of Hematology and the American Society of Transplant and Cellular Therapy and has expertise in hematological malignancies including Hodgkin and non-Hodgkin lymphoma, multiple myeloma, acute myeloid leukemia, acute lymphoblastic leukemia, chronic lymphocytic leukemia, chronic myeloid leukemia, and myelodysplastic syndrome. 

Dr. Fesler earned a medical degree from Saint Louis University School of Medicine, followed by internal medicine residency at the University of Colorado Health Sciences Center, where he was chief resident in his final year. He completed a fellowship in hematology and oncology at Saint Louis University School of Medicine and is board-certified in both hematology and medical oncology. 

Nikki Yuill is a bilingual (Spanish) Clinical Oncology Social Worker with more than 25 years of healthcare and oncology experience. She attended Purdue University in Indiana for her undergraduate degrees, and she completed her graduate work at the University of Texas at Austin.

Yuill has experience in blood cancers, solid tumors, andhematopoietic stem cell transplantation. She has extensive knowledge of and experience in advocacy, education, and support of blood cancer patients and their families. Yuill has a particular interest in adolescent and young adult cancer care, healthcare disparities, and serving the Latinx community.

Yuill is the director of the Information Resource Center at The Leukemia & Lymphoma Society (LLS), a global leader in the fight against cancer. LLS funds lifesaving blood cancer research around the world, provides free information and support services, and is the voice for all blood cancer patients seeking access to quality, affordable, coordinated care. Yuill is a proud member of the AOSW (Association of Oncology Social Workers). In 2020 she was awarded the AOSW LLS Oncology-Hematology Lifetime Achievement Award because of her longstanding efforts on behalf of cancer patients.