Number of incident cancers dropped as pandemic took hold

Last Updated: 2020-08-06

By Anne Harding

NEW YORK (Reuters Health) - The number of newly identified patients with cancer declined significantly after the onset of the pandemic, a new analysis of clinical laboratory data suggests.

For six common types of cancer, the average number of new cases identified per week declined by 25% to 52% after COVID-19 hit, Dr. Harvey W. Kaufman and colleagues at Quest Diagnostics in Secaucus, New Jersey, report in JAMA Network Open.

"Some cancers grow very slowly but others grow a little bit faster and these delays can be significant for some patients," Dr. Kaufman told Reuters Health by phone. "There's definitely going to be some increases in the staging of cancers and there will be some people who will unfortunately die as a consequence."

Dr. Kaufman and his team identified more than 278,000 patients who had undergone testing at Quest between January 1, 2018, and April 18, 2020, and had also received a new ICD-10 code for breast, colorectal, lung, pancreatic, gastric, or esophageal cancer.

Up to February 29, 2020, the mean number of patients diagnosed per week with any of the six cancers was 4,310. The weekly average fell to 2,310 during the pandemic (March 1, 2020-April 18, 2020), a 46.4% drop.

Each individual cancer also showed a significant decline, from 24.7% for pancreatic cancer to 51.8% for breast cancer. The drop was sharpest over the first three weeks of March and leveled off toward the end of the month.

During the pandemic, the American Society of Clinical Oncology (ASCO) recommends that cancer screening requiring in-person visits be postponed, "to conserve health system resources and reduce patient contact with health care facilities."

But this is not a blanket statement, Dr. Richard L. Schilsky, the chief medical officer and executive vice president of ASCO, told Reuters Health by phone. "Those are decisions that have to be weighed between the doctor and the patient, in terms of making a decision about whether to postpone a recommended screening test and for how long," he added. The decision must take into account the patient's cancer risk, as well as the likelihood of exposure to COVID-19, he said.

"ASCO has not recommended, nor would we, that any symptomatic patient have their evaluation delayed, but the same sorts of considerations apply," he added.

While a delay in diagnosis does indeed increase the risk that a cancer will be found at a more advanced stage, when it is less treatable, "there's no way from the data they present to know how many of these newly identified cancers are in people who might have been foregoing screening or people who might have been foregoing symptom evaluation," Dr. Schilsky said.

"Concerns about increases in cancer deaths in the years ahead are based on statistical modeling and assumptions, but that's all they are, they're risk models, and so whether or not someone who has a cancer diagnosed outside of a recommended screening interval is destined to die from that cancer, that's highly conjectural," he added. "Many of these patients will still be cured by an appropriate cancer treatment implemented at the time of diagnosis."

He concluded: "Generally speaking, I think anybody who has a new symptom that could be a symptom of cancer should seek medical evaluation in a timely fashion."

SOURCE: https://bit.ly/3ibcIZb JAMA Network Open, online August 4, 2020.