Waiting for treatment to start can be an excruciating period for cancer patients. There can be fears that the disease is spreading, or progressing to a point where therapies become less effective. Yet over the last few decades, the time cancer patients are waiting between diagnosis and treatment has steadily grown, according to a new study of more than 2.7 million patients.

“What was striking was the consistency,” said Tim Donahue, the senior author on the study and a surgical oncologist at the University of California, Los Angeles. “Across every cancer we studied, patients are waiting longer today than they were a decade ago.”

Donahue and his colleagues analyzed data from the National Cancer Database, a national data repository from the American College of Surgeons, from 2012 to 2023. They looked only at patients with stage 1 to 3 cancers that were considered eligible for surgery at diagnosis across six different cancers. Then, they compared the time between diagnosis and any first treatment, which included surgery as well as radiation or chemotherapy or other medical therapies.