Delaying initiation of cancer treatment by just four weeks is associated with increased mortality rates for patients with seven types of cancers, regardless of treatment type, researchers reported in BMJ.

Researchers conducted a systematic review and meta-analysis of 34 studies involving 1,272,681 patients. The studies evaluated curative, neoadjuvant, and adjuvant indications for surgery, systemic treatment, or radiotherapy for bladder, breast, colon, rectum, lung, cervical, and head and neck cancers.

Delaying treatment for 13 of the 17 total indications had a statistically significant association with increased mortality rates. Specifically, for each four-week treatment delay, mortality risk increased 6%–8% for surgery, 1%–28% for systemic therapy, and 1%–23% for radiotherapy.

“A four-week delay in treatment is associated with an increase in mortality across all common forms of cancer treatment, with longer delays being increasingly detrimental,” the researchers said. “The prevailing paradigm has been around access to new treatments to improve outcomes, but from a system level, gains in survival might be achieved by prioritizing efforts to minimize the time from cancer diagnosis to initiation of treatment from weeks to days. In light of these results, policies focused on minimizing system-level delays in cancer treatment initiation could improve population-level survival outcomes.” 

The findings also have implications as patients and providers currently discuss decisions about starting treatment versus protecting patients from potential virus exposure.