She Wasn’t Due For Her Colonoscopy. A Blood Test Found Cancer Anyway

InnovationHealthcareShe Wasn’t Due For Her Colonoscopy. A Blood Test Found Cancer AnywayByAdaira Landry, MD MEd,Contributor.Forbes contributors publish independent expert analyses and insights. Physician who writes about the rising rates of cancer in young adults.Follow AuthorJun 02, 2026, 01:22pm EDTJun 02, 2026, 01:23pm EDT--:-- / --:--This voice experience is generated by AI. Learn more.This voice experience is generated by AI. Learn more.Kim Turner in the hospital with her daughterKim TurnerColorectal cancer is the second leading cause of cancer-related death in the United States. It is also one of the most preventable — if caught early, the five-year survival rate exceeds 90%. And yet more than 45 million eligible Americans are due or overdue for screening. While education of colon cancer symptoms and screening guidelines exist, patients still have to contend with understanding of and access to screening tools.Colonoscopy remains the gold standard, but completing one requires bowel prep, sedation, time off work, and an available specialist. Depending on the research study, only 20 to 40% of patients actually follow through with the entire colonoscopy. For those who complete screening, guidelines for average-risk adults who get a clean colonoscopy result ask patients to return in up to 10 years for repeat colonoscopy.That 10-year gap is where Kim Turner's story lives.Colonoscopy screening intervalsTurner, a physician assistant in Alaska, had her first colonoscopy at 50, which found a one-centimeter precancerous polyp. Her follow-up at 54 was clear. She has no family history of cancer, obesity, or smoking. Her gastroenterologist told her she didn’t need another colonoscopy for 10 years.In 2025, Kim’s daughter organized a health fair and suggested a blood-based colorectal cancer screening test called Shield, by Guardant Health. Kim agreed casually. "I didn’t expect it to come back positive," she said. However, at just 61, 3 years before being due fo...