Run for the Rarest Cancers
Join Rare But Relentless Foundation at the Miami Life Time 305 Half Marathon and help move ultra-rare cancer research forward.
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Rare But Relentless Foundation is bringing runners together to raise awareness and accelerate progress for ultra-rare sarcomas and other rare cancers. Every mile represents patients and families facing diseases that receive far too little research, funding and attention.
A Founder's Journey
In January 2026, founder and president Zach Fenster completed the Miami Half Marathon without knowing that an aggressive tumor was growing in his right thigh. Six weeks later, an incidental scan led to his diagnosis, followed by chemotherapy, radiation, major surgery and months of rehabilitation.
Returning to Miami represents more than a race—it shows that even the hardest setbacks can become a starting point for hope, purpose and progress.
What donations support
Accelerating Research
Funding high-impact genomic studies and biomarker discovery for the rarest sarcomas.
Connecting the Community
Expanding Resources
Building a robust network for families to share data and insights that drive discovery.
Providing navigational support and educational tools for newly diagnosed patients.
Help Us Reach the Finish Line
Every contribution—at any amount—helps bring greater attention, collaboration and urgency to the rarest cancers.
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