Prompt Resumption of Screening Programme Reduced the Impact of COVID-19 on New Breast Cancer Diagnoses in Northern Italy

SIMPLE SUMMARY: The aim of this study was to compare 2020 tumours with 2019 tumours by age, stage and treatment in four different periods. In 2020 there was no decrease of invasive tumours nor in situ (513 vs. 493 and 76 vs. 73, respectively), while there was a significant decrease in surgery and an increase in neoadjuvant chemotherapy (p = 0.016). During the Italian lockdown period (March–May), we observed a decrease in all ages and a significant one among people aged 75+ [IRR 0.45 (95% CI 0.25–0.79)], but in the last period there was a significant increase among people of the screening age range of 45–74 [IRR 1.48 (95% CI 1.11–1.98)]. Screening activities were suspended from March to May, but over the summer and the autumn the backlog was eliminated. This suggests that a prompt resumption of programmed screening may have limited the impact of the pandemic on the delay of breast cancer diagnoses. ABSTRACT: The aim of this study is to evaluate the real impact of COVID-19 during the entire 2020 period, compared with 2019. The data comes from a Cancer Registry in Northern Italy and we compared clinical and treatment characteristics of breast cancer by age, stage, treatment, and status screening. In 2020 there was no decrease in invasive tumours nor in in situ (513 vs. 493 and 76 vs. 73, respectively), while there was a significant decrease in surgery and increase in neoadjuvant chemotherapy (p = 0.016). In the screening range (aged 45–74), no change in stage and grading was observed. In the four periods examined there was an increase in new diagnoses during pre-lockdown, a decrease in tumours especially at age 75+ [IRR 0.45; 95%CI 0.25–0.79] during lockdown, a recovery of new diagnoses in women 45+ in the low incidence period while in the last period there was a significant increase only for ages 45–74 [IRR 1.48; 95% CI 1.11–1.98]. Screening activities were suspended from March to May, but over the summer and autumn the backlog was addressed. This suggests that a prompt resumption of programmed screening may have limited the impact of the pandemic on the delay of breast cancer diagnoses.