Marcia K. Horn

Marcia K. Horn

Marcia K. Horn is the President and CEO of ICAN, International Cancer Advocacy Network. Marcia is a patient advocate and research advocate who has provided direct navigation services for thousands of late-stage cancer patients since the founding of ICAN in 1996. She is also a molecular profiling advocate, a clinical trials matching advocate, a health equity advocate, and a health technology advocate.

Marcia oversees four biomarker-specific groups that are part of ICAN:

Biomarker Collaborative ( is an international consortium of biomarker groups and general cancer organizations emphasizing comprehensive biomarker testing and clinical trials.

Exon 20 Group ( is an international coalition and multi-stakeholder organization dedicated to better managing and then curing cancers caused by two gene mutations each found in more than 25 cancers: EGFR exon 20 and HER2 exon 20 insertions.

MET Crusaders ( focus on MET gene alterations: METex14 skipping mutation/amplification/overexpression.

PD-L1 Amplifieds (, focus on “PD-L1 Amplification” a diagnosis found only by next-generation sequencing (NGS)/comprehensive biomarker testing. If found, PD-L1-amplified patients may be candidates for immune checkpoint blockade therapy.

In addition to her responsibilities at ICAN, Marcia is very active in the cancer community nationally and internationally. She was one of the two research advocates for the Stand Up 2 Cancer Molecular Early Detection of Colon Cancer Dream Team from 2014-2022, and is currently a patient advocate for the Stand Up 2 Cancer InTIME Dream Team for Lung Cancer Interception. She has been a member of the American Society of Clinical Oncology’s TAPUR Study Molecular Tumor Board for seven years and has been a member of the Banner Health Institutional Review Board for ten years. In 2012, Marcia was named inaugural chair of the Drug Information Association’s (DIA) Patient Engagement Community and served for three years. She was selected as one of the first PCORI Ambassadors (Patient-Centered Outcomes Research Institute).

Marcia has served as a research advocate for the SWOG for Cancer Research Early Therapeutics/Rare Cancers Committee since 2014, and is also a member of SWOG's Sarcoma Working Group. Since 2017, she has been a patient advocate for the University of Texas Southwestern Medical Center/University of Texas MD Anderson Cancer Center Lung Cancer SPORE (a National Cancer Institute Specialized Program of Research Excellence). She was accepted as a member of FT3, From Testing to Targeted Treatments, as a patient advocate in 2022. In 2023, she was selected for the IASLC Rare Tumors Committee and is a co-lead on one of their major projects.

Marcia is a Phi Beta Kappa graduate of Stanford University in Political Science and received her JD from the Stanford Law School. Before joining ICAN, she practiced litigation and appellate law in Phoenix and held leadership positions in Arizona arts and civic organizations.

Marcia, based in Phoenix, Arizona, is the proud mom of son Yoni Horn, a graduate of Arizona State University and Pepperdine Law School, who is currently practicing law in Los Angeles.



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