Marcia K. Horn

Marcia K. Horn

Marcia K. Horn is President and CEO of ICAN, the International Cancer Advocacy NetworkAdvocacy Network,

At ICAN, Marcia is a research advocate who has directly navigated thousands of pan-tumor patient cases since the founding of the organization in 1996.  She is a molecular profiling advocate, a clinical trials matching advocate, an expanded access/compassionate use advocate, a public policy advocate, and a health equity advocate. 

Since 2017, Marcia has served as the Executive Director of the Exon 20 Group,, an international multi-stakeholder coalition created to transform cancers caused by rare pan-tumor EGFR exon 20/HER2 exon 20 insertion mutations into manageable diseases. She also directs The PD-L1 Amplifieds, a support group for pan-tumor cancer patients who are PD-L1 (CD274) amplified by next generation sequencing.  

In 2012, Marcia was selected as DIA's inaugural chairman of its Patient Engagement Community and served for three years.  She was named one of the first PCORI Ambassadors. 

Marcia 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 ASCO TAPUR Study Molecular Tumor Board for six years and has been a member of the Banner Health Institutional Review Board for nine years.  

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. She was selected as a patient advocate for the University of Texas Southwestern Medical Center/University of Texas MD Anderson Cancer Center Lung Cancer SPORE (an NCI Specialized Program of Research Excellence) in 2017. In 2021, Marcia was elected to the Board of Directors of the Biomarker Collaborative and serves as its Vice President. She joined FT3, From Testing to Targeted Treatments, as a patient advocate in 2022.

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 the Arizona arts community.


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