Gabriel Mannis


Associate Professor of Medicine (Hematology)

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Dr. Gabriel Mannis is Associate Professor of Medicine in the Division of Hematology at Stanford University School of Medicine, and Medical Director of Stanford’s Inpatient Leukemia Service. He specializes in the treatment of acute myeloid leukemia (AML), high-risk myelodysplastic syndromes (MDS), and other hematologic malignancies. As a clinical scientist, Dr. Mannis divides his time between caring for patients, teaching trainees, and researching novel therapies for AML and MDS. Dr. Mannis has co-authored numerous publications on topics including AML, hematopoietic cell transplantation, and advanced care planning for patients with hematologic malignancies. Currently, Dr. Mannis serves on the National Comprehensive Cancer Network AML panel, helping to write evidence-based guidelines for how AML is best treated. He oversees the AML clinical trial portfolio at Stanford, with multiple clinical trials of novel drugs actively enrolling for both newly diagnosed and relapsed or refractory AML.

Professional Summary

Education & Certifications
  • Residency: UCSF Dept of Internal Medicine (2011) CA
  • Board Certification: American Board of Internal Medicine, Hematology (2015)
  • Board Certification: American Board of Internal Medicine, Medical Oncology (2014)
  • Board Certification: American Board of Internal Medicine, Internal Medicine (2011)
  • Fellowship: UCSF Hematology and Medical Oncology Fellowship (2014) CA
  • Medical Education: University of California Davis School of Medicine (2008) CA

Administrative Appointments
  • Medical Director, Stanford Hospital Inpatient Hematology Service (2021 - Present)
  • Member, Stanford Cancer Institute (2019 - Present)
  • Panel Member, Acute Leukemia Working Group, Southwest Oncology Group (SWOG) (2019 - Present)
  • Panel Member, Acute Myeloid Leukemia Guidelines Committee, National Comprehensive Cancer Network (2019 - Present)


Clinical Trials

Clinical trials are research studies that evaluate a new medical approach, device, drug, or other treatment. As a Stanford Health Care patient, you may have access to the latest, advanced clinical trials.

Open trials refer to studies currently accepting participants. Closed trials are not currently enrolling, but may open in the future.

Practice Locations

Hematologic Cancer Program Palo Alto, CA
Palo Alto, CA

875 Blake Wilbur Drive

Palo Alto , CA 94304

(650) 498-6000

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Patient Ratings

(34 Ratings)

Overall Rating

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Explanations the care provider gave you about your problem or condition
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The Patients Ratings and comments are gathered from our Patient Satisfaction Survey and displayed in their entirety.

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Patient Reviews

(80 reviews)

Positive attitude. Answers questions honestly and directly. I trust his judgement.
I can see why Dr. Mannis does many interviews on YouTube, his bedside manner is incredible and a pleasure to listen to.
He’s awesome! Knowledgeable, informative, friendly and professional.
Dr. Mannis is an excellent doctor and I would recommend him to anyone going through what I have been going through.
Very thorough and involved with my situation.
He is the best!
Dr. Mannis is an awesome doctor. Very knowledgeable, professional, and friendly.
Visit was efficiently and professionally operated
Excellent communicator and very knowledgable
He’s a great healthcare provider and a nice person.
Dr. Mannis continues to be engaging and warm as well as extremely knowledgeable. I feel completely confident in my care with Dr. Mannis at the helm.
Wonderful doctor
I feel reassured and more knowledgeable after our visits.
Dr Mannis and staff are exceptional
Thank you, Dr. Mannis for everything.
Thorough and concise.
None. The doctor clearly knew my chart and medical treatment history.
I think it is a great doctor
Excellent doctor
Outstanding, professional, compassionate and incredibly knowledgeable specialist whom I am thrilled to now be under the care of!
A truly expert and humane doctor.
It is alwsys a pleasure seeing Dr. Mannis. He is warm, professional, personal & an excellent doctor.
Excellent listener and considerate demeanor.
First of all, I want to say that Dr. Mannis is the best out of the best. He is always nice, professional and caring; I am very lucky to have him as my doctor. Both of my husband and I trust him deeply. He is truly fostering empathy, compassion, kindness and hope! Thank you so much Dr. Mannis!
I found him to be very informative and professional
Dr. Mannis is a wonderful doctor. I appreciate everything he has done for me.
Dr. Mannis is as good as it gets in his field. Appreciated his realistic opinion about the risks involved in a transplant situation.
In my experience (73 years) Dr Mannis ranks up there with the best doctors I have dealt with. I really can’t say enough about his expertise as an MD and his delightful personality.
Overall, great doctor…
He is great
The best care I can ever imagine. Thank you.
Talk to Mannis is an exceptional position and individual. He cares for his patients.
Excellent experience with dr. Mannis and rest of overall treatment at Stanford.
I have confidence in him. Good man and good doctor.
He is a great doctor. Very knowledgeable and quite capable of answering general and very specific ones too. Very few doctors are as approachable as he always is.
I have been seeing the Doctor for a little over 3 years. He "designed" my program and so far it has been wonderful. My leukemia seems to be in remission. (although we won't know unless we do a biopsy) He is very patient and understanding and I still remember our initial visit and how wonderful and patient he was to explain what was going to happen to me with my Leukemia. Super sharp !!
The BEST!!!!
Dr. Mannis was very informative and explained things well. We felt comfortable talking with him and greatly appreciate how much he's working with our local oncology doctor.
Dr. Mannis always shows concern about my well-being and is very caring. I enjoy our telehealth appointments.
He is fantastic. Saved my life!!!
Excellent physician. Always interested in my overall condition as well as the specific condition that is under treatment. Wonderful sense of humor. Encouraging, caring and focused on welfare.
The staff at the infusion center are knowledgeable, thorough, and very personable. They make it not only bearable, but even fun.
I feel that Dr. Mannis tailored my treatment to meet my needs and was very sensitive to my situation and the urgency of it. I am so very grateful for him and his team and look forward to starting treatment soon and with confidence even though he was clear that it would not be easy. At least it’s a chance! He gave me hope.
Explained everything well.
Truly professional, empathetic, honest and upfront. Medically explained everything very well. I'll be seeing him tomorrow
Great Dr for my needs.
When I was diagnosed with AML, Dr. Mannis was my first contact at Stanford. After explaining the medical treatment regime, he then took the time to discuss with my wife and I the probability of success, medical implications, and end-of-life options to consider. The clear, compassionate explanation of what lay ahead greatly reduced my anxiety. Throughout the year-long procedure, Dr. Mannis stayed in contact and even visited during a chemo session. Now, that I have been leukemia free with no GVHD for more than 2 years, Dr. Mannis still personally follows up to check on my medical and psychological process. Dr. Mannis is an exceptional physician, and human being, who demonstrates genuine concern for his patients.
Dr. Mannis is always warm, compassionate, friendly and a really wonderful doctor. He let's me ask silly questions and never seems annoyed by them. It's always a pleasure visiting with him and I trust him completely.
Appreciated Dr. Mannis's time today.
Excellent Hematologist. And I've had experience with many.
Hear Mannis is very easy to talk to. He is very caring and informative.
He’s great!
I am very lucky to have him on my case.
Dr. Mannis is absolutely the best!!!!
Very professional and well versed on where we are with my case and protocols.
Dr. Mannis is very likeable, easy to talk to, compassionate and seems like a really nice person. I always look forward to seeing him and know that he will be honest and considerate even when it's bad news.
Dr Mannis and his team are excellent. They take the time to listen to you, answer all your questions and to make you feel comfortable with treatment options.
Very pleased with him.
I am very happy to have my care in his hands.
I have found him to be an excellent MD and a compassionate human being.
Absolutely wonderful physician
Pleasure to speak to Dr Mannis
Over a period of 2 years plus association, Dr. Gabriel Mannis has been not just the medical professional / adviser but friend, philosopher and guide. We will not forget him.
Very nice and generous Doctor.
He's great.
Thank you so much for your hard work & kindness :)
This is my first time with only few minutes of video call with Dr. Mannis, so far so good and Dr. Mannis did clearly spoke and explained everything in this call.
Dr. Mannis is extremely focused on my care and is so professional in his interaction with me. He takes the time to answer all of my questions in a caring way. His team is also doing a great job with making sure that our communications are in sync. Thank you to everyone!
Dr. Mannis is FABULOUS! He saved my life!
Excellent MD
He is wonderful. Great bedside manner, seems like he really cares, very genuine and knowledgeable. And he cured me! Cannot say enough wonderful things about Dr. Mannis. Thank you!!!
Dr Mannis is very knowledgeable and clear with his plans for treatment
Dr Mannis came very highly recommended by my local oncologist Dr James Link, who admires Dr Mannis very much. Dr Link is leaving the local practice in 6 weeks, and I am sure that he felt better having Dr Mannis take over my case than any of the other local oncologists. I was impressed that he pinpointed a big issue with treating my AML, being that I have a problem with normal living in that my heartbeat races with the slightest expenditure of energy. That will have to be dealt with before Dr Mannis can use any aggressive action on the cancer. His parting words to me were, "We will see how tough you are". Dr Link was aware of the heart complication but could not get an appointment with a cardiologist for me as that specialty is locally short staffed. Dr Mannis has made it Step 1 to get me seen by a cardiologist up at Stanford. I would like to know if I may communicate directly with Dr Mannis via text or email as I have been able to do with Dr Link.
He is an extremely knowledgeable physician with excellent interpersonal skills. I am lucky to have him as my doctor.
An excellent, knowledgeable kind Doctor.
Dr. Mannis is very professional. He keeps on top of treatment options and answers all of my questions. He shows great compassion towards my best interest regarding my overall health and quality of life. I am happy that he is my doctor.
Best doctor I’ve dealt with. Makes me feel special and takes time to explain any questions I might have. Never feel rushed. Wish more doctors and their staff were the same!!!
Very informative
I feel very confident in Dr. Mannis

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