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Marisa O'Neill, DO

Marisa O'Neill, DO

Breast Surgery

Provider Groups

  • Trinity Health IHA Medical Group

Primary Contact

(734) 712-1700

Services & Specialties

Areas of Specialization

  • Breast Surgery

Locations & Contact

Primary Location

Trinity Health IHA Medical Group, Breast Surgery - Ann Arbor Campus

5320 Elliott Dr
Ste 203
Ypsilanti, MI 48197

View hours
Monday
8:00am - 5:00pm
Tuesday
8:00am - 5:00pm
Wednesday
8:00am - 5:00pm
Thursday
8:00am - 5:00pm
Friday
8:00am - 5:00pm
Trinity Health IHA Medical Group, Breast Surgery - Ann Arbor Campus

Trinity Health IHA Medical Group, Breast Surgery - Chelsea

14650 E Old US Hwy 12
Ste 303
Chelsea, MI 48118

View hours
Monday
8:00am - 5:00pm
Tuesday
8:00am - 5:00pm
Wednesday
8:00am - 5:00pm
Thursday
8:00am - 5:00pm
Friday
8:00am - 5:00pm
Trinity Health IHA Medical Group, Breast Surgery - Chelsea

About

Marisa O’Neill, D.O., is a board-certified surgeon specializing in breast surgical oncology. Dr. O’Neill specializes in the care of patients with breast cancer and benign breast diseases, including the evaluation and management of high-risk breast lesions. Her surgical practice incorporates advanced techniques such as oncoplastic surgery and nipple-sparing mastectomy. She is dedicated to shared decision-making and prioritizes comprehensive patient education to ensure informed choices aligned with individual goals and values.

Insurances Accepted

  • Aetna
  • Aetna (Medicare Advantage)
  • Aetna Better Health of Michigan
  • BCBS Michigan (Medicare Advantage)
  • Blue Care Network of Michigan
  • Blue Cross Complete of Michigan
  • BlueCross Blue Shield Michigan
  • Cofinity
  • Community Care Associates
  • Health Alliance Plan of Michigan
  • Humana Medicare Advantage
  • McLaren Health Plan
  • Medicaid Michigan
  • Medicare Michigan
  • Meridian Health Plan
  • Molina Healthcare of Michigan
  • Priority Health
  • Priority Health Medicaid
  • Priority Health Medicare
  • Railroad Medicare Michigan
  • Tricare Humana Military
  • Tricare Prime Remote
  • Trinity Health
  • United Healthcare
  • UnitedHealthcare Community Plan Michigan
  • University of Michigan Health Plan
  • Veterans Choice Program
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Education & Certifications

Education

Fellowship:
McLaren Flint Hospital

Residency:
Corewell Health Farmington Hills Hospital

Internship:
Corewell Health Farmington Hills Hospital

Medical School:
Michigan State University at East Lansing

Board Certifications

American Board of Surgery

Provider Groups

Trinity Health IHA Medical Group

Provider Ratings

The following ratings and reviews are based on verified feedback collected from independently administered patient experience surveys. The ratings and comments submitted by patients reflect their own views and opinions. Patient identities are withheld to ensure confidentiality and privacy. Learn More >

4.9 out of 5

(219 ratings)

The Patient Satisfaction Rating is an average of all responses to the care provider related questions shown below from our survey. Patients that are treated in outpatient or hospital environments may receive different surveys, and the volume of responses will vary by question.

86 Reviews

03/06/2026

She did a great job for me last and I have no concerns about my upcoming lumpec

03/06/2026

Dr. O'Neill is very thorough and makes you feel comfortable. She explains everything to you to help you understand what is going on. She listens to you and answers any questions you may have.

03/02/2026

Marisa was friendly but professional and thorough. Even her attire was professional. In reviewing her education and credentials I feel she is well educated and capable. I spent many years working in surgery myself and am confident that I have an excellent surgeon.

02/27/2026

Dr O’Neill is an excellent doctor. She explains things thoroughly and makes her patients feel comfortable.

02/27/2026

Beautiful woman inside and out.

02/27/2026

Wonderful Dr!

02/17/2026

Her examination was thorough, and her instructions were clear.

02/17/2026

Dr. O'Neill put me at ease.

02/13/2026

I would definitely recommend Dr. O’Neil to anyone that I know to be cared for by her. She is very caring and thoughtful.

02/06/2026

She was very professional and caring.

01/30/2026

The surgeon was incredibly communicative, validating my concerns and ensuring I understood and felt comfortable with the plan.

01/27/2026

I felt comfortable with Dr. O'Neill and she was honest and forthright in her opinion as to how my treatment should proceed. She gave me the assurance I needed to make the right decision about my treatment.

01/23/2026

Excellent doctor, will refer to ladies in the future if/when they gave breast cancer.

01/20/2026

A friend gave me Dr. O'Neill's name after she went through treatment with her. I was initially diagnosed through U of M. I switched doctors after having a horrible experience during a breast biopsy. They wanted me to go through another biopsy for another spot that they did not test in the first biopsy. Dr. O'Neill did not make me go through another biopsy. The spot was dealt with during the lumpectomy. Dr. O'Neill is great. I highly recommend her!!

01/02/2026

I feel she is a wonderful doctor and I trust her with my care.

12/19/2025

She is an Angel- My family and I are so grateful for her! She is so real and down to earth and comforting

12/12/2025

I have only heard very positive reviews about Dr. O’Neill.

08/29/2025

A wonderful, caring very competent physician!

08/22/2025

I highly recommend Dr. O'Neill to anyone needing breast surgery. Her attention to my questions was outstanding. I am still healing from my procedure but expect my incision will be almost invisible once fully healed.

08/14/2025

Personable & professional excellent Dr

08/12/2025

Very knowledgeable, polite, answered our questions.

08/09/2025

She was very concern about me! I truly appreciate how she cared for me!

08/08/2025

Shes very professional & personable. Excellent Dr

08/08/2025

She listened to what I had to say and answered my questions clearly.

08/01/2025

I’m feeling confident she will take good care of me in my sirgery.

07/15/2025

She made me feel very comfortable and explained everything completely.

07/13/2025

explains thoroughly in a way we could understand.

07/11/2025

Loved her-I felt well cared for

07/11/2025

Dr. O’Neill made me feel comfortable from the beginning to the end of my appointment. She did a wonderful job explaining my test results & answered all of our questions.

07/08/2025

I really like Dr. O'Neill. She was very understanding and explained everything in a way I could understand.

07/03/2025

Dr. O'Neill, listens, problem solves, is compassionate and very good at explaining in a way that you can follow and understand.

07/01/2025

I appreciate feeling I've been heard and feel the best solutions decisions have been made for my care.

07/01/2025

Very courteous..explanation...listens carefully..spends time with you and does not rush out..even before my surgery explanation of what I was to expect and outcome.

06/21/2025

Dr. O’Neill is amazing. She makes you feel so comfortable. She listens and cares about your feelings. I come in feeling anxious and leave feeling everything is going to be fine! My surgery from last year healed up wonderfully also. I really do appreciate her and I am so happy I chose her to be my surgeon.

06/13/2025

I left my appointment well informed.

06/13/2025

Kind and compassionate, reassuring

06/11/2025

Dr. O'Neill was great! She was very thorough and professional while at the same time treated me as though I was her only patient that day. She spent plenty of time making sure that I understood everything and answered any questions I had without making me feel rushed. I would definitely recommend Dr. O'Neill and her staff.

06/10/2025

I would highly recommend Dr. O'Neill. She was very personable, thorough, yet professional.

06/10/2025

She was very patient with me as I vented a bit.

06/07/2025

Professional, caring patient in her explanations.

05/21/2025

Pleasant, knowledgeable and takes the time to explain everything clearly, and answers all questions.

04/29/2025

Dr. O'Neill was kind, caring and compassionate. She spent a great deal of time explaining my diagnosis and treatment plan. I never felt as if there was anything more important than me during the time I was with her.

04/29/2025

Visit was excellent...no problems

04/22/2025

Dr O’Neill was caring and knowledgeable. She provided excellent care.

04/22/2025

This process is challenging to go through. It really helps to feel comfortable and to trust the people treating you.

04/18/2025

It was informative, comfortable. I left feeling I was in the right hands.

04/15/2025

I never felt as though I was just another patient. I was treated with courtesy and respect at all times

04/15/2025

From the 1st time I met Dr. O'Neill I was impressed with her knowledge, compassion, and communication skills. Feeling this way made me comfortable the day of surgery. I was relaxed which always leads to a better experience.

04/01/2025

Really it was a crappy day and it wasn't their fault. I was treated good.

03/30/2025

dr. o'neill is very bright, extremely professional, well-informed with good bedside manner. I'm relieved she is my breast surgeon.

03/28/2025

I didn't know anything about dr. o'neill, as she was assigned to my case, rather than my choosing the breast surgeon of my choice, as I did in 2002 for my first go-around with breast cancer. I was nervous that we wouldn't connect, but extremely relieved that she was a good choice for me. I feel I'm in good hands with a well-informed doctor with good bed-side manner.

03/28/2025

Had a great experience

03/04/2025

I left with a smile on my face!

03/04/2025

I recognized her knowledge and ability to present it. I appreciated having my out of state son join us by phone.

02/19/2025

Lucky to have Dr. O’Neill as my surgeon!

02/18/2025

Totally satisfied!

02/18/2025

Dr. O’Neill at the very first made us feel very comfortable. She explained the results and answered our questions so that we could understand. She took her time with us and made sure we knew we could call if we had additional needs or questions.

02/14/2025

Professional, friendly, kind, patient

02/11/2025

My husband and I were very impressed with her and feel very confident in her ability.

02/01/2025

Dr. O'Neill's ability to explain and to instill confidence in me was above the usual initial doctor/patient experience.

01/31/2025

I think the scheduler went above and beyond the call of duty.

01/31/2025

I very much appreciate the promptness with which I was contacted by office staff and being seen within 2 days.

01/21/2025

This was my first meeting with Dr. O'Neill. She was warm, attentive, and unhurried.

01/14/2025

Felt confidence in her and respected her

01/08/2025

Very knowledgeable and addressermy concerns

01/07/2025

My visit went well and I will be back for a follow up in May.

01/07/2025

worked with me fand rescheduled a new date to see the surgon on the same day I was their

01/02/2025

Doctor O‘Neill took her time to explain my future health care and to make my decision on how to proceed. Her knowledge of my upcoming procedure made me relaxed and comfortable!

12/27/2024

Satisfied all the way around!

12/13/2024

Dr. O’Neill you are an amazing surgeon

12/13/2024

Appreciated her direct, informative explanations.

11/30/2024

Very professional and caring Dr looking very the bedside manner. Thank u

11/29/2024

Pleasent visit

11/12/2024

A scary beginning made very much more hopeful.

11/12/2024

I felt very comfortable talking with Dr. O’Neill and felt a great deal of relief after I knew what my treatment plan was.

10/25/2024

I felt that there was a wait from the waiting room, to the patient room, until the doctor came in. I didn’t have many questions and the doctor mentioned that that was unusual. Since I have been home, my list has grown to twenty questions!

10/18/2024

A real good appointment

10/11/2024

Great experience in a stressful situation

10/08/2024

No complaints. I would recommended her to anyone. I am very happy she is my selected surgeon.

08/23/2024

My family thought "she is the kind of doctor everyone should have!"

08/23/2024

Great experience always!

08/20/2024

Dr O’Neill was exceptional. Very personable, listens and explains status and plan.

08/06/2024

The provider was down to earth and caring about my feelings. Explained my disease in a way I could understand and made me feel much better about it. She knew how bad I needed to get the surgery over with and got me in very fast!! I left the office feeling so much better. I highly recommend dr. Oneil.

07/30/2024

I was made to feel that I was an active part of my care team and that my decisions were accepted and respected even when they did not always follow recommendations. I felt like I had control over my healthcare.

07/30/2024

Dr. O'Neil treated me with respect. She explained things to me in a manner that made it easier for me to understand the information she was giving me. She relieved a lot of the anxiety I was feeling

07/09/2024

Dr. O'Neill seemed to be compassionate and caring in her conversation with me and the way she treated my concerns.
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