The power of preventive cancer screenings can be measured in dramatically increased survival rates when cancers are diagnosed at their most curable stages by the thousands of mammograms, cervical tests and colonoscopies performed each year.

In fact, preventive screenings can be credited with a breathtaking 12 million more years of life for Americans in the quarter century since the U.S. Preventive Services Task Force formed, according to a recent study in BMC Health Services.

For many forms of cancer, screening and early detection remain limited or elusive. For solid tumors—such as lung, pancreatic and ovarian cancers—investigators continue searching for solutions to make screening accurate, available and accessible. Earlier detection, more accurate risk assessment and better risk management are important goals for addressing cancers that defy screening.

In 2015, lung cancer care reached a pivotal milestone: Medicare started covering screening with a low-dose CT scan for people at increased risk of developing lung cancer. Though it remains the leading cause of cancer death, advances in treatment and screening availability have made important inroads in less than a decade and are credited with a 4% dip in lung cancer death rates per year from 2017 to 2021, according to the American Cancer Society. Combined with steady declines in tobacco use, lung cancer mortality is decreasing.

In late 2023, the American Cancer Society increased eligibility by simplifying the guidelines, opening screening to 5 million more people by lowering the age threshold and offering screening to any current or former smoker regardless of when they quit.

"The challenge with lung cancer is beyond the actual screening," said Sara Ghandehari, MD, director of the Centralized Lung Cancer Screening Program. "We have to confront the stigma surrounding lung cancer and encourage those who are eligible to go through screening."

Nationally, only 4.5% of people at high risk for lung cancer were screened—with California last among the states at 0.7%.

Furthermore, smoking history still drives screening eligibility. In the U.S., up to 20% of lung cancers are diagnosed in people who never smoked or smoked fewer than 100 cigarettes in their lifetime, according to the Centers for Disease Control and Prevention.

"There are other factors that cause lung cancer, and we don’t know what all of them are, so some people develop the disease who were never eligible for screening," Ghandehari said.
 

Read: Lung Cancer Screening Demystified

Pancreatic cancer is expected to become the second most common cause of cancer death, surpassing breast and colorectal cancers, but not because of an increased incidence in diagnoses. Advances in screening tools and treatment for breast and colorectal cancers are resulting in greater success in treating them.

Pancreatic cancer has no unique symptoms to alert physicians and encourage early diagnosis.

"Pancreatic cancer is a devastating disease, and we need to give people some hope," said Stephen Pandol, MD, director of Basic Translational Pancreas Research and program director of the Gastroenterology Fellowship at Cedars-Sinai.

That hope is on the horizon.

Pandol and Debiao Li, PhD, who directs the Biomedical Research Institute and holds the Karl Storz Chair in Minimally Invasive Surgery in honor of Dr. George Berci at Cedars-Sinai, and their colleagues developed an AI tool that has the potential to predict pancreatic cancer based on CT scans. The team assembled CT scans of pancreatic cancer patients taken months and years before they were diagnosed with pancreatic ductal carcinoma, the most common form of pancreatic cancer. The AI tool recognized subtle early signs of the disease that the human eye could not discern.

"Physicians frequently order CT scans for patients with abdominal symptoms, so we have large CT scan libraries and the clinical data that go with them," Pandol said. "We are working with six medical centers across the U.S. to identify patients who had a CT scan six months to 10 years before a pancreatic cancer diagnosis."

Read: The Link Between Pancreatic Cancer and Diabetes

Predicting and preventing ovarian cancer have been lifelong dreams of many cancer researchers, said gynecologic oncologist B.J. Rimel, MD, medical director of the Cedars-Sinai Cancer Clinical Trials office.

"We’ve had one clinically useful biomarker for ovarian cancer since 1981," she said. "But science moves ever forward."

Investigators at the Gilda Radner Hereditary Cancer Program envision creating a risk score for ovarian cancer based on multiple factors. One would be genetic predisposition, such as having a BRCA1 or BRCA2 pathogenic variant. For about 80% of patients, who do not have a BRCA variant, more data is becoming available on many other variants in the genome, each of which contribute small amounts of risk.

"As more of these variants are identified, we are better able to predict an individual’s risk," said Michelle Jones, PhD, assistant professor of Biomedical Sciences and director of the Human Genetics and Genomics Core. "We need to move toward approaching cancer with prevention—not treatment—as the priority."