TABLE I.

Modelled estimates of the cumulative number of breast cancer cases delayed in Ontario because of restrictions on surgical capacity^a

Estimate	Reduction in operating room capacity
	80%	60%	40%
Cases deferred (n)
After 1 monthb	699	524	350
After 2 monthsc	1140	855	570
After 3 monthsc	1520	1140	760

^aAssumptions: restrictions persist for 3 months, rate of restriction is constant, 1000 new breast cancer cases are typically diagnosed per month. Those numbers do not include patients who are not diagnosed because of lack of screening.

^bRepresents patients already diagnosed before the pandemic whose surgeries were postponed. Assumes 950 breast surgeries per month (1000 breast cancers diagnosed per month – 5% stage IV cases for which surgery is not performed), with 92% of eligible surgeries being scheduled and completed within 1 month of the decision to operate.

^cAssumes that 475 stages I–III breast cancers continue to be diagnosed while imaging is on hold and an equal number of patients are starting neoadjuvant therapy as others are completing neoadjuvant therapy.