U.S. cancer diagnoses drop, outcomes worse during holidays

GAINESVILLE, Fla. — The December holiday season is a joyous time for family, friends, festive parties and gift-giving. Americans take time off from work and often put off life’s demands until the new year.

Cancer, however, doesn’t take a holiday.

A new University of Florida Health study examining more than 30 million cancer diagnoses nationally between 2001 and 2019 found that December has the fewest cancer diagnoses and worst survival, while January has the most diagnoses.

Researchers don’t believe this is a statistical fluke. They said several factors could explain the pattern. For example, some individuals might delay seeing a doctor for early symptoms until after the holidays. Specialist access and staffing might be particularly limited in December.

Abdul-Qahar Yasinzai, M.D., the UF Health physician-scientist who led the research, said health insurance challenges might also, at least in part, explain the phenomenon. Individuals might wait until January for insurance calendar resets, policy activation and deductible status updates.

The study was published earlier this month in JAMA Network Open.

“Several cancers are on the rise in the entire United States population due to an aging population and risk factors, including even in younger people,” said Yasinzai, who recently left UF Health for Louisiana State University at Shreveport, where he is completing an internal medicine residency.

“This might point to the need for policy changes in medicine, like more staffing availability in months with worse survival and lower diagnostic activity,” he added. “In cancer, delayed diagnostic workup often leads to stage migration and thus worse outcomes.”

The proportion of “distant-stage diagnoses” — those cancers that have spread more widely in the body — is highest in January. Yasinzai said this could be related to delayed diagnoses.

But he cautioned that a monthlong difference would not necessarily have a significant impact on metastasis in many solid cancers.

The study noted that seasonal variation in diagnoses might not be limited to cancer.

“Is there less catheterization of cardiac patients in December and more in January?” Yasinzai said. “Are more patients dying from heart problems when diagnosed in some months rather than others? This might also vary among health systems, with some more vulnerable and under-resourced than others.”

The study examined all cancer types, drawing on data from the National Program of Cancer Registries and the Surveillance, Epidemiology and End Results registry. The data analyzed is largely representative of the U.S. population, the study said.

Yasinzai said the quality of the hospital system might one day be measured, in part, by these seasonal fluctuations.

“This generates a metric in which we can judge how consistent the health care system is in dispensing services across calendar months,” he said.

The difference in diagnoses between December and January might seem relatively small, with a 1% difference, the study said. That, however, amounts to 300,000 diagnoses and a “substantial absolute difference at the population scale,” it noted.

Another interesting trend stands out in the study: Breast cancer diagnoses rise in October.

“The best chance we have against many cancers is to find them early, when they are most curable,” Yasinzai said. “That is what makes our October finding so interesting. October is Breast Cancer Awareness Month, and it had the highest proportion of cancers diagnosed at an early stage and the best five-year survival of any month.”

The same pattern, however, was absent in other cancer awareness months, such as pancreatic cancer in November or kidney cancer in March. Unlike breast cancer, these cancers are harder to detect early and do not have established routine screening options.

Thomas J. George, M.D., deputy director of the UF Health Cancer Institute and a professor in the UF College of Medicine’s division of hematology and oncology, is the senior author of the study.