According to a recent analysis, the delays in the initiation of cancer treatments caused by the COVID-19 pandemic significantly increase the mortality associated with several types of cancer.
Current cancer treatments are much more effective when they are directed at early tumors, which have not yet reached an advanced clinical stage. For this reason, timely management of newly diagnosed cancer patients is often one of the most important parameters in successfully eradicating cancer cells and successfully conquering the disease.
On the other hand, even under normal conditions, starting anticancer treatments as quickly as possible remains a challenge for the majority of health systems around the world and it is recognized that delays can have negative consequences on the therapeutic success of these treatments. However, the real impact of these delays on cancer-related mortality remains unclear.
The importance of better understanding the concrete consequences of these treatment delays is particularly urgent in the context of the COVID-19 pandemic.
Many countries, including Canada, have had to redirect the resources available to deal with the skyrocketing of patients severely affected by this viral infection, which at the same time has resulted in the postponement of several other medical procedures, including some cancer treatments. .
To quantify the impact of these delays, a team of researchers from Queen’s University (Kingston, Ontario) analyzed the results of 34 studies that looked at this issue around the world.(1).
These studies contained data on surgical procedures, systemic therapy (such as chemotherapy) or radiotherapy for seven forms of cancer, namely those of the bladder, breast, colon, rectum, lung, cervix. uterus and head and neck, which collectively account for 44% of all newly diagnosed cancers worldwide.
The effect of treatment delays was measured by examining the overall survival of patients for each four-week delay between diagnosis and the first treatment or between the end of one treatment and the start of the next.
Analysis of the results showed that for the three types of treatment (surgery, chemotherapy and radiotherapy), a four-week delay in treatment was associated with an increased risk of death, i.e. an increase of 6 to 8% for postponements. for surgery and 9 to 13% for chemotherapy and radiotherapy. Longer delays have even more pronounced effects: for example, an eight week delay in breast cancer surgery would increase the risk of death by 17%, up to 26% for a 12 week delay.
Concretely, the authors estimate that a surgical delay of 12 weeks for all patients with breast cancer for one year could lead to as many as 700 additional deaths in Canada.
The harmful consequences of COVID-19 are therefore not limited only to those affected by this disease, but also affect patients affected by cancer whose treatment is delayed due to the offloading of cancer treatments. It is therefore crucial to take this data into account to minimize these delays as much as possible and improve the likelihood of these patients of surviving cancer.
(1) Hanna TP et al. Mortality due to cancer treatment delay: systematic review and meta-analysis. BMJ 2020; 371: m4087