Dennis Massimo doesn't remember when he signed up for the Penn Medicine BioBank, but his sister Lauren Massimo, does. It was 2016, Dennis, then 33, was getting his tonsils out, and Lauren encouraged him to consent to his blood sample being banked for future research.

A stored blood sample saved his life—then revealed a hidden cancer risk

Lauren, an associate professor of nursing at Penn's School of Nursing with Penn Medicine appointment in neurology, where she co-directs the Frontotemporal Degeneration Center, was used to being her family's trusted health advocate. That decision may have saved his life.

In April 2025, Dennis was 42 and working as a construction estimator, kept getting-and ignoring-calls from the BioBank. Having no memory of signing up for it nine years earlier, he assumed the calls were spam or a sales pitch. Finally, on April 14, he picked up the phone.

Dennis learned that a research project using samples from the BioBank found something called an MSH2 gene mutation in his DNA. As soon as he hung up the phone, he called Lauren. Soon they learned that Dennis had Lynch syndrome, a condition that puts him at an increased risk for cancer. As if that wasn't enough news, a tumor was already silently growing in his colon: stage III colorectal cancer that likely wouldn't have been discovered and treated for years, had Dennis not followed his sister's urging and signed up for the BioBank.

At 42, Dennis was still three years away from the recommended age for an average-risk person to begin getting screening colonoscopies. But due to his Lynch syndrome status, earlier screening was highly recommended. Three weeks later, Dennis underwent a partial colectomy with Najjia N. Mahmoud, chief of colon and rectal surgery.

"Dennis says. "She was confident, clear, and incredibly reassuring. When you're facing cancer surgery, that level of trust means everything."

Read more at Penn Medicine News.