Alexander Gregory Hayden, MD
I speak: English
My gender: Male
Where I practice
About me
I am originally from Indiana and completed my undergraduate and medical school education at Indiana University. I then moved to the great state of Colorado to complete an internal medicine residency followed by a Hematology and Oncology fellowship at the University of Colorado. After completing training, I was delighted to join the exceptional group of medical oncologists at Kaiser Permanente.
About my practice
I consider it an immense privilege to enter into the lives of my patients as they navigate the highs and lows of their healthcare journeys. I strive to provide high-level, compassionate care by addressing patient’s primary hematologic or oncologic conditions while also treating the whole person by considering social, mental health, cultural, and other factors that may impact their care decisions. Oncology is a particularly dynamic specialty, and I am continually inspired by the many evolving new therapeutics that promise to improve the lives of the patients I serve. I believe in empowering my patients with the latest clinical trials and other evidence-based advances so they can make informed decisions on their personalized treatment plan.
My Cancer Subspecialty Focus
I provide care to patients across all cancer types and hematologic conditions with a special interest in gastrointestinal cancers, breast cancer, myeloma, genitourinary cancers, lymphoma, and central nervous system malignancies.
Collaboration on Multidisciplinary Teams
I work closely with a multidisciplinary team of experts within the fields of radiation oncology, surgery, pathology, radiology, and palliative care among other specialties. These teams allow us to provide high-level, evidence-based care tailored to each patient’s clinical needs.
Research & Clinical Trials Involvement
I participate in several National Cancer Institute–supported clinical research networks, including the SWOG Cancer Research Network, National Surgical Adjuvant Breast and Bowel Project (NSABP), Alliance for Clinical Trials in Oncology, and NRG Oncology. As a sub-investigator on multiple clinical trials, I help bring forward new and promising therapies for patients in our community. I am also committed to research in cancer survivorship, aiming to improve long-term health, reduce recurrence risk, and enhance quality of life beyond treatment.
How I thrive
Outside of work I thrive through spending quality time with my wife and our beloved dog Rory, along with our family and friends. I also love exploring all of the wonderful activities and unique places Colorado has to offer. I particularly enjoy gardening, golfing, hiking, and skiing.
Medical groups and plans
Colorado Permanente Medical Group
Contact information
- Appointments/Cancellations/Information
- 303-338-4545
- Appointments/Cancellations/Information
- 1-800-218-1059 (toll free)
Hours:
- Extended weekday hours are currently unknown.
- Weekend hours are currently unknown.
Please call the office directly for information regarding hours.
Languages spoken by front-office staff:
EnglishPlans accepting new patients
- Child Health Plan Plus (CHP+)
- Colorado HMO/EPO
- KP Select
- Kaiser Permanente Colorado Option for Individual & Family
- Kaiser Permanente Colorado Option for Small Group
- Medicare-Denver Boulder
- Medicare-Northern Colorado
- Medicare-Southern Colorado
- Medicare/Medicaid Dual-Enrolled
Indicates if the clinician’s office/facility has accommodations for people with physical disabilities, including offices, exam room(s), and equipment.
My training, certifications & licensing
Medical school
Indiana University School of MedicineBoard certification
Internal Medicine
American Board of Internal MedicineTo verify board certification for an individual practitioner, please visit the American Board of Medical Specialties, the American Medical Association, or the American Osteopathic Association websites.
Medical training
Fellowship
Oncology & Hematology
University of Colorado School of MedicineResidency
Internal Medicine
University of Colorado School of MedicineJoined Permanente Medical Group
2026Provider ID
029788My hospitals
This information is not available at this time.
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PHYSICAL DISABILITIES ACCOMMODATIONS
It is Kaiser Permanente’s policy to make our facilities, services, and programs accessible to individuals with disabilities, in compliance with federal and state laws that prohibit discrimination based on disability. Kaiser Permanente provides reasonable accommodations to individuals with disabilities, including: (1) access to service animals and their users, except where the animal poses a significant risk to health or safety; (2) appropriate auxiliary aids and services when necessary to ensure effective communication with individuals with hearing, cognitive, and/or communication-related disabilities, including qualified sign language interpreter services and informational materials in alternative formats (examples include large print, audio tape/CDs, electronic texts/disks/CD-ROMs, and Braille); and (3) accessible exam rooms and medical equipment for individuals with disabilities. If you have a specific question, please contact Member Services, Monday through Friday, 8 a.m. to 6 p.m., at 1-303-338-3800 or 1-800-632-9700 (TTY 711).
This page was last updated on: 10/19/2026