Imma Perfetto
Cosmos science journalist
COVID-19 brought an unprecedented shift in the approach to breast cancer screening and treatment in Australia.
A retrospective clinical analysis of data from patients at Sydney Adventist Hospital (SAH) in New South Wales has linked an increase in cases of advanced breast cancer since the pandemic to breast screening suspensions which occurred due to COVID-19 restrictions.
Researchers from the Australian National University looked at new cases of female breast cancer diagnosed at SAH between July 2019 and June 2022, and categorised them into pre-pandemic, pandemic, and post-pandemic groups.
They found an increase in patients with advanced breast cancer (stage 3 or 4) in the pandemic and post-pandemic group (8.5% and 7%), compared to the pre-pandemic group (4.6%).
The research is published in the ANZ Journal of Surgery. Previous reports have found little evidence that COVID-19 delays created worse health outcomes for women being screened for breast cancer.
Breast cancer specialist and radiation oncologist at the Australian National University College of Health & Medicine, John Boyages says the SAH study showed some worrying trends for patients with more aggressive cancers.
“Aggressive cancers are known to grow more quickly. For example, for oestrogen receptor-negative tumours, the rate of node-positivity doubled, increasing from 33% to 66% from the pre- to post-pandemic periods,” says Boyages who was lead author of the research.
“Node-positive breast cancer” means that cells from the tumour have metastasised and been found in the lymph nodes in the armpit area.
“The increased probability of having cancer spread to a patient’s lymph nodes and delayed diagnosis is likely to translate into poorer patient outcomes in the longer term,” says Boyages.
“Our study clearly shows government and health authorities need to prioritise cancer screening in future pandemics.”
Breast cancer is the most common cancer affecting women in Australia, accounting for an estimated 12.7% of all new cancer diagnoses and 6.4% of all cancer deaths in 2022. The national BreastScreen Australia program offers free breast screening for women aged over 40.
However, according to the authors: “in the initial stages of the pandemic, COVID-19 impacted breast screening and general healthcare attendance, with many women cancelling or postponing their appointments and adhering to the ‘stay-at-home’ message put forward by the Government.”
A report by the Australian Institution of Health and Welfare in 2022 said breast screening was delayed or postponed during the COVID-19 outbreak in 2020.
“To protect clients, staff, and the community from the risk of COVID-19, BreastScreen Australia services were suspended nationwide from 25 March 2020. The suspension was lifted around a month later for most services, but a staged approach was introduced with longer appointment times and precautionary measures to ensure the safety of clients and staff. The rate at which BreastScreen services could resume was affected by jurisdictional social distancing and infection control guidelines and requirements. Most BreastScreen services stayed open, with these additional precautionary measures, for the remainder of the year despite additional lockdowns and increasing numbers of cases of COVID-19.”
The program also faced further suspensions in the latter half of 2021.
A report in late 2022 looked at the impact of the breast screening delays in 2020, and concluded that in NSW the impact was small.
Researchers from Cancer Institute NSW say a retrospective analyses demonstrated “no evidence of a substantial change in the size of tumours diagnosed by BreastScreen NSW in clients whose breast cancer screening was delayed by the suspension of service due to the COVID-19 pandemic.”
But they said the findings may not reflect all Australian states and territories, due to variations in COVID restrictions and lockdowns.
The SAH study found that patients with symptomatic breast cancer at diagnosis increased from 42.3% in the pre-pandemic, to 53.1% in the pandemic and 57% in the post-pandemic.
But Boyages says it was not all bad news.
“During the same period, there was an increased use of shorter courses of radiation, and we became more experienced in radiation courses as short as one week,” he says.
“We also increased the use of more chemotherapy before surgery to work out if a cancer is sensitive to the planned chemotherapy leading to a shift in less mastectomy rates: 33% pre-pandemic versus 24% post-pandemic.”
The authors caution that the population this study was conducted on may not be representative of nationwide populations.
“Patients in this catchment are likely to have greater healthcare access, and therefore higher attendance for screening and subsequent treatment,” they write.
“Further studies involving multi-centre analysis may be beneficial in establishing trends in breast cancer during the pandemic.”
