Mark Sitarik, MD

Medical Oncologist / Hematologist

Mark Sitarik, MD | Oncologist at Rocky Mountain Cancer Centers


4715 Arapahoe Ave.
Boulder, CO 80303


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Secondary Location(s)

Boulder Breast Specialists

4715 Arapahoe Ave.
Boulder, CO 80303


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About Mark Sitarik, MD

Dr. Mark Sitarik is a board-certified medical oncologist. As a founding member of the Boulder Rocky Mountain Cancer Centers office, Dr. Sitarik is well-known in the Boulder area for his expertise. His practice emphasis includes breast cancer, colorectal cancer, lung cancer, urological cancers, and blood cancers including leukemia, lymphoma, and multiple myeloma. Dr. Sitarik has built a strong connection with other cancer specialists such as surgeons, radiation oncologists, pathologists, and radiologists. His participation in multiple weekly tumor boards with these other specialists is critical to his patients’ care. Through sharing their expertise and reviewing cancer cases, these experts will determine the most ideal cancer treatment strategy for the patient. Dr. Sitarik’s partnership with US Oncology provides him immediate access to the most cutting-edge therapies and current clinical research trials. The hallmark of his practice is to provide his patients the best care available.

Advanced Practice Providers Working With Dr. Sitarik

Board Certifications

Medical Oncology




Medical Oncology, University of Colorado Health Sciences Center, Denver, CO


Internal Medicine, University Hospitals of Cleveland, Cleveland, OH

Medical School

Hahnemann Medical College and Hospital, Philadelphia, PA

Patient Care Philosophy

I have had the privilege of serving the citizens of Boulder in my private practice of medical oncology since 1987. My objective is to assess the medical, emotional, and life journey goals of my patients and mesh those goals into a state-of-the-art, evidence-based treatment plan that best serves the needs of that individual. I strive to give an honest assessment of any given clinical situation. Only through that honest assessment and open discussion can a patient make the best treatment decision in any given set of circumstances.

Additional Information

American Society of Clinical Oncology