How Early Detection Through PRECEDE Changed One Patient’s Future

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“If sharing my story helps even one person get screened, then everything I went through is worth it.” — Shanna Thomas, PRECEDE participant 

When Shanna Thomas walked into her first appointment at Moores Cancer Center at UC San Diego Health, she didn’t know that moment would change the trajectory of her life. For years, pancreatic cancer had been a devastating thread woven through her family history. Her sister was diagnosed in 1998 and passed away just months later. A year later, her mother received the same diagnosis and passed away shortly after entering hospice.

“It was so fast,” Thomas recalls. “After watching what my mom and sister went through, I just feel grateful to have another chance.”

Because of her family history, Thomas underwent periodic imaging for years, but routine screening fell away during the pandemic. In 2024, an unexpected diabetes diagnosis prompted her physician to order a magnetic resonance imaging (MRI) scan, which revealed pancreatic atrophy. A follow-up endoscopic ultrasound identified a benign cyst with abnormal cellular changes, serious enough to warrant expert evaluation. Determined to understand her risk, Thomas sought care at UC San Diego Health.

“By the stroke of a pen, I got an appointment with Dr. Simeone,” she says. “I remember thinking, ‘How did I get to see her?’ I felt really lucky.”

Thomas vividly remembers her first meeting with Diane M. Simeone, MD, director of Moores Cancer Center and founding director of the Pancreatic Cancer Early Detection (PRECEDE) Consortium. Sitting eye to eye, Simeone walked her through the scans and explained why more information was needed.

“When we see subtle changes like this in someone with a strong family history, we have an opportunity to intervene early,” Simeone says.

Simeone recommended additional imaging and introduced Thomas to PRECEDE, a program with more than 11,000 participants that aims to raise survival rates for pancreatic cancer. This international early detection effort led by Moores Cancer Center identifies high-risk individuals before cancer advances. For Thomas, learning about PRECEDE clarified why she needed to be here.“My husband and I looked at each other and thought, ‘This is where we’re supposed to be,’ Thomas says.

The PRECEDE team in the Multidisciplinary Pancreatic Tumor Clinic coordinated her next steps, including additional imaging, expert review and a clear pathway for early intervention. “I felt valued as a person, not just a patient,” she says. 

After completing the evaluation, Thomas met with team member Theodore “Ted” H. Welling, MD, Professor of Surgery, UC San Diego HPB surgical oncologist, to discuss the surgical plan first raised by Simeone. He moved forward immediately to map out her surgical plan and treatment. Her operation and recovery were seamless. 

During her recovery, both Simeone and Welling visited her in the hospital, reaffirming she was in the right hands.

Pathology later confirmed high-grade dysplasia with no evidence of invasive cancer, validating that early surgical intervention prevented the development of invasive pancreatic cancer. High-grade dysplasia represents the earliest possible stage of pancreatic cancer (carcinoma in situ) and carries a significant risk of progressing to invasive disease if left untreated.  

Today, Thomas continues annual surveillance and remains cancer-free. She proudly wears a handmade button titled “early detection survivor,” honoring her mother and sister. “If sharing my story helps even one person get screened,” she says, “then everything I went through is worth it.”

Moores Cancer Center remains a national leader in early pancreatic cancer detection, with programs like PRECEDE, one of many efforts at the center working to change outcomes for high-risk families like Thomas’s — before cancer begins.