Paris (AFP)

Delaying treatment for cancer for even a month has a significant impact on the risk of patient mortality, shows a study published Wednesday, which strengthens the conclusions of other research warning about the deleterious effect of the Covid pandemic- 19 for other diseases.

Supply tensions over certain treatments are already a frequent problem in normal times.

But the spread of the coronavirus has caused unprecedented disruptions in access to health services around the world.

In the study published by the British medical journal BMJ, British and Canadian researchers analyzed the consequences of delayed treatment (surgery, radiotherapy, chemotherapy, etc.) for seven types of cancer, based on 34 studies published in the last twenty years.

Outside the pandemic, "delays in treatment are the exception but can still affect 10% to 15% of patients," oncologist Ajay Aggarwal, one of the study's authors, told AFP.

He concludes that even a month's delay can cause a 6% to 13% more risk of dying for the patient.

And the longer the delay, the greater the risk.

Postponing by 12 weeks the operation of all women with breast cancer requiring surgery - as during confinements linked to Covid-19 for example - would result in 6,100 additional deaths in a year in the United States, and 1,400 in the UK, say the authors.

- Reprogramming -

Conclusions that "invite reflection", they believe, while many hospitals have had to reschedule operations considered "non-urgent" in order to increase the number of beds and caregivers available for patients with Covid-19 .

"Some countries have published recommendations on the prioritization of cancer surgeries, which the results of this study do not seem to validate", explain the researchers.

In the UK, for example, it was considered that certain treatments, such as colorectal surgeries, could be delayed for 10 to 12 weeks without negative impact on the prognosis for the patient.

However, "we found that reducing the waiting period for this type of operation to 12 weeks instead of 6 increased the risk of mortality by 9%", stress the researchers.

Overall, a four week delay for surgery increases mortality from 6% to 8%, and the risk of such a delay increases to 9% for radiation therapy for head and neck cancer.

It goes up to 13% in certain situations, such as adjuvant treatment (which supplements the main treatment to prevent a risk of recurrence) of colorectal cancers.

If this delay increases to eight or twelve weeks, for breast cancer surgery, the risk of mortality increases by 17% and 26% respectively, they calculate.

Another study published in July in The Lancet Oncology estimated that delays in diagnosis in the United Kingdom since mid-March would translate into around 3,500 additional deaths from four types of cancer within five years in this country.

An article published in August in the JAMA Network Open showed him that the number of cancers diagnosed each week in the United States had fallen by nearly 50% in March and April.

© 2020 AFP