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​​​“Patients always come first for me. I treat everyone as relatives and friends. I will give everyone my best, every time!”

Provider Bio down arrow

Dr. Adedayo Onitilo is the director of Cancer Care and Research. He is principal investigator of WinCORP, which provides access to NCI-sponsored clinical trials to more than 680,000 people in Wisconsin, and parts of Michigan, Iowa and Minnesota. He is editor-in-chief for Clinical Medicine and Research, a publication of original scientific medical research. He also holds a clinical faculty position at the University of Wisconsin.

Dr. Onitilo enjoys working in the Health System because it allows him to practice exceptional medicine and conduct landmark research. “It’s rare to be able to wear both hats,” he said. “We are doing groundbreaking research now that may help patients worldwide.”

Dr. Onitilo is board certified in internal medicine, hematology, medical oncology and hospice and palliative medicine. He earned his medical degree at Ogun State University in Nigeria. He did his residency at Columbia University, College of Physicians and Surgeons - Harlem Hospital in New York. Dr. Onitilo completed a fellowship in oncology/ hematology and earned a master of science degree in clinical research at the Medical University of South Carolina. He earned a doctorate degree in epidemiology from The University of Queensland, Australia. Dr. Onitilo is a member of the Wisconsin chapter of the American Cancer Society and Wisconsin Cancer Council steering committee.

In his spare time, you’ll find Dr. Onitilo displaying his ping-pong skills or working on his golf game. As a physician who has lived and practiced throughout the world, he loves to travel and meet new people. He is happily married with children.​

Professional Summary down arrow

  • Medical School
    Ogun State University Sagamu, Ogun State, Nigeria, M.D. 1995

    Internship
    Columbia University College of Physicians & Surgeons - Harlem Hospital Center New York, NY, United States, Internal Medicine 1999

    Residency
    Columbia University College of Physicians & Surgeons - Harlem Hospital Center New York, NY, United States, Internal Medicine 2001

    Fellowship
    Medical University of South Carolina Charleston, SC, United States Oncology/Hematology 2004

    Medical University of South Carolina Charleston, SC, United States Master of Science - Clinical Research 2004

  • Academic Appointments
    Clinical Associate Professor, Department of Medicine-University of Wisconsin School of Medicine and Public Health Madison, WI

    Professional Societies
    American College of Physicians American Society of Clinical Oncology American Society of Hematology International Society for Experimental Hematology

    Board Certifications
    Hematology: 2004, recertified 2014 Hospice & Palliative Medicine: 2005 Internal Medicine: 2002, recertified 2012 Medical Oncology: 2004, recertified 2014

    State Licenses
    South Carolina Wisconsin

    Areas of Interest
    Associate Editor, Clinical Medicine & Research Journal Clinical Practice & Research

Patient Ratings down arrow

4.8
out of 5 (241 ratings, 21 comments)
4.8
Provider explanations of my problem
4.8
Provider concern for my questions
4.8
Provider's efforts to include me in treatment decisions
4.8
Provider's discussion of proposed treatment
4.8
My likelihood of recommending this provider

Patient Comments down arrow

Comments are also gathered from the Press Ganey patient satisfaction survey and displayed in their entirety with the exception of any language that may be considered slander, libel or contain private health information, which will be removed prior to publishing.
Comments are from Press Ganey surveys. Slander, libel and private health information are removed.
Sort by:
February 22, 2023
Dr. O is a great doctor great communicator.
April 24, 2023
Excellent care
May 18, 2023
Good.
June 12, 2023
Great, both doctor and nurses
June 14, 2023
Dr. Onitilo is a caring, gentle person, AND PATIENT!
June 22, 2023
I would definitely refer Dr. O. to anyone else - I find he is an INTELLIGENT DR.
August 28, 2023
Doctor very knowledgeable and concerned about me and my concerns.
September 13, 2023
I have shared my experience with this doctor and staff, and they now are taking advantage seeing this doctor and staff.
October 2, 2023
Dr. Onitilo is very caring & respectful.
October 25, 2023
I highly recommend this clinic!!!
November 17, 2023
Dr. Onitilo is the best!
November 22, 2023
I have recommended friends with similar cancer to Marshfield Cancer Clinic. They too feel they are receiving outstanding care
November 28, 2023
The cancer care and research staff are OUTSTANDING!!
November 29, 2023
My interaction with all levels of staff at an individual level was very positive
November 29, 2023
Dr. Onitillo was excellent.
December 18, 2023
I am so happy to have found Dr Onitillo. He provides compassionate and professional care.
December 29, 2023
Dr. Onitillo always is very professional and caring to me as his patient. He literally has saved my life with his precise treatment.
July 18, 2023
Lucky to have such a talented oncolcgist.
April 24, 2023
Good.
October 9, 2023
Prior to treatment, did not discuss options with me. During treatment had no interest in addressing side effects. Extremely short visits. I could have just viewed my results online. No reason to actually see the doctor.
November 21, 2023
Dr. Onitilo is always in a hurry. Does not explain anything. Becomes very "short" when we ask question. Does not like to be challenged. Do not friendly.
November 21, 2023
Dr. Onitilo is always in a hurry. Does not explain anything. Becomes very "short" when we ask question. Does not like to be challenged. Do not friendly.
October 9, 2023
Prior to treatment, did not discuss options with me. During treatment had no interest in addressing side effects. Extremely short visits. I could have just viewed my results online. No reason to actually see the doctor.
April 24, 2023
Good.
July 18, 2023
Lucky to have such a talented oncolcgist.
February 22, 2023
Dr. O is a great doctor great communicator.
April 24, 2023
Excellent care
May 18, 2023
Good.
June 12, 2023
Great, both doctor and nurses
June 14, 2023
Dr. Onitilo is a caring, gentle person, AND PATIENT!
June 22, 2023
I would definitely refer Dr. O. to anyone else - I find he is an INTELLIGENT DR.
August 28, 2023
Doctor very knowledgeable and concerned about me and my concerns.
September 13, 2023
I have shared my experience with this doctor and staff, and they now are taking advantage seeing this doctor and staff.
October 2, 2023
Dr. Onitilo is very caring & respectful.
October 25, 2023
I highly recommend this clinic!!!
November 17, 2023
Dr. Onitilo is the best!
November 22, 2023
I have recommended friends with similar cancer to Marshfield Cancer Clinic. They too feel they are receiving outstanding care
November 28, 2023
The cancer care and research staff are OUTSTANDING!!
November 29, 2023
My interaction with all levels of staff at an individual level was very positive
November 29, 2023
Dr. Onitillo was excellent.
December 18, 2023
I am so happy to have found Dr Onitillo. He provides compassionate and professional care.
December 29, 2023
Dr. Onitillo always is very professional and caring to me as his patient. He literally has saved my life with his precise treatment.
February 22, 2023
Dr. O is a great doctor great communicator.
April 24, 2023
Good.
April 24, 2023
Excellent care
May 18, 2023
Good.
June 12, 2023
Great, both doctor and nurses
June 14, 2023
Dr. Onitilo is a caring, gentle person, AND PATIENT!
June 22, 2023
I would definitely refer Dr. O. to anyone else - I find he is an INTELLIGENT DR.
July 18, 2023
Lucky to have such a talented oncolcgist.
August 28, 2023
Doctor very knowledgeable and concerned about me and my concerns.
September 13, 2023
I have shared my experience with this doctor and staff, and they now are taking advantage seeing this doctor and staff.
October 2, 2023
Dr. Onitilo is very caring & respectful.
October 9, 2023
Prior to treatment, did not discuss options with me. During treatment had no interest in addressing side effects. Extremely short visits. I could have just viewed my results online. No reason to actually see the doctor.
October 25, 2023
I highly recommend this clinic!!!
November 17, 2023
Dr. Onitilo is the best!
November 21, 2023
Dr. Onitilo is always in a hurry. Does not explain anything. Becomes very "short" when we ask question. Does not like to be challenged. Do not friendly.
November 22, 2023
I have recommended friends with similar cancer to Marshfield Cancer Clinic. They too feel they are receiving outstanding care
November 28, 2023
The cancer care and research staff are OUTSTANDING!!
November 29, 2023
My interaction with all levels of staff at an individual level was very positive
November 29, 2023
Dr. Onitillo was excellent.
December 18, 2023
I am so happy to have found Dr Onitillo. He provides compassionate and professional care.
December 29, 2023
Dr. Onitillo always is very professional and caring to me as his patient. He literally has saved my life with his precise treatment.
December 29, 2023
Dr. Onitillo always is very professional and caring to me as his patient. He literally has saved my life with his precise treatment.
December 18, 2023
I am so happy to have found Dr Onitillo. He provides compassionate and professional care.
November 29, 2023
My interaction with all levels of staff at an individual level was very positive
November 29, 2023
Dr. Onitillo was excellent.
November 28, 2023
The cancer care and research staff are OUTSTANDING!!
November 22, 2023
I have recommended friends with similar cancer to Marshfield Cancer Clinic. They too feel they are receiving outstanding care
November 21, 2023
Dr. Onitilo is always in a hurry. Does not explain anything. Becomes very "short" when we ask question. Does not like to be challenged. Do not friendly.
November 17, 2023
Dr. Onitilo is the best!
October 25, 2023
I highly recommend this clinic!!!
October 9, 2023
Prior to treatment, did not discuss options with me. During treatment had no interest in addressing side effects. Extremely short visits. I could have just viewed my results online. No reason to actually see the doctor.
October 2, 2023
Dr. Onitilo is very caring & respectful.
September 13, 2023
I have shared my experience with this doctor and staff, and they now are taking advantage seeing this doctor and staff.
August 28, 2023
Doctor very knowledgeable and concerned about me and my concerns.
July 18, 2023
Lucky to have such a talented oncolcgist.
June 22, 2023
I would definitely refer Dr. O. to anyone else - I find he is an INTELLIGENT DR.
June 14, 2023
Dr. Onitilo is a caring, gentle person, AND PATIENT!
June 12, 2023
Great, both doctor and nurses
May 18, 2023
Good.
April 24, 2023
Good.
April 24, 2023
Excellent care
February 22, 2023
Dr. O is a great doctor great communicator.

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