An increase in node-positive and stage III breast cancer after two months interruption in breast cancer screening due to COVID-19 pandemic was reported by Dr Angela Toss of the Department of Oncology and Hematology, Azienda Ospedaliero-Universitaria di Modena in Modena, Italy and colleagues in an article published on 11 February 2021 in the ESMO Open. These findings support recommendations for a quick restoration of breast cancer screening at full capacity, with adequate prioritisation strategies to mitigate harm and meet infection prevention requirements. 

The analysis aimed to evaluate the consequences of interruption of mammographic screening of breast cancer for two months in a region of North Italy that was highly affected by COVID-19. Response to the pandemic was rapid reorganisation and allocation of healthcare resources, staff and infrastructure to minimise exposure risks. Prioritisation further aimed to avoid negative impact on patient outcomes, especially in oncology. 

Majority of organisations and oncology institutions published their recommendations, driven by a common goal to save hospital resources for COVID-19 patients and reorganise cancer management strategies. The majority of these recommendations stated that population mammographic screening and screening of mutation carriers should be suspended until the pandemic subsides. 

The study authors reported that the Italian College of Breast Radiologists provided recommendations for procedural prioritisation of breast imaging and cancer diagnosis during the COVID-19 pandemic. The recommendations were mainly aimed at asymptomatic women who did not respond to the invitation for screening mammography after the onset of the pandemic and those who were informed of the suspension of the screening activity. It was recommended to postpone the check preferably within 3 months of the originally scheduled date, as long as the operating conditions allow for it. However, the real impact of a temporary mammographic screening suspension on breast cancer outcomes was uncertain. 

This retrospective single institution analysis compared the clinical pathological characteristics of breast cancer diagnosed between May 2020 and July 2020, after two months screening interruption, with breast cancer diagnosed in the same trimester of 2019 when mammographic screening was regularly performed. 

The authors found that two months stop in mammographic screening produced a significant decrease of 10.4% in in situ breast cancer diagnosis and an increase of 11.2% in node-positive and of 10.3% in stage III breast cancer. 

A major impact was on the subgroup of patients with breast cancer at high proliferation rates. Among these patients, the rate of node-positive breast cancer increased by 18.5% and stage III by 11.4%. 

In the subgroup of patients with low proliferation rates, a 9.3% increase in stage III tumours was observed, although node-positive tumours remained stable. 

The authors reported that despite screening interruption, procedures to establish a definitive diagnosis and start the treatment were subsequently carried out without delay. 

The authors commented that postponing screening procedures as a result of the COVID-19 pandemic was prudent at one time, at the beginning of the pandemic. However, the spread, duration and future peaks of COVID-19 are unpredictable. They underline that overlooking other life-threatening conditions such as breast cancer for too long may turn one public health crisis into another.