Paris (AFP)

The authorities have hammered out the importance for cancer patients to continue their treatment during the coronavirus epidemic, but the consequences on management have been very real and the emergency will be required after the deconfinement, warn specialists.

"My last treatment was postponed for six weeks. With a phone call to tell me that it was less dangerous than exposing myself to the Covid", worries Roger (first name changed at his request), 62, still in immunotherapy following lung cancer.

Adèle, 40, was in full treatment for breast cancer diagnosed in September, when the epidemic spread in France. This Parisian then decides to confine herself to the family home in the provinces.

The transfer of her treatment finally went well and she is now waiting to start radiotherapy, but "at one point I asked myself, where will I be followed? Will I be in the nature?"

Between processing delays and those in the detection of new cases, it is the whole system that risks being destabilized.

"During these two months, the number of cancers diagnosed was halved," said Professor Axel Kahn, president of the League against cancer, citing the feedback from the hospital field.

"Obviously, it was not the coronavirus that scared the cancer, the cancer is still there. On the other hand, the coronavirus scared the patients who were dissuaded from being screened, to consult".

- "Large traffic jam" -

The figures are simple and worrying: with nearly 400,000 new cases of cancer per year in France, some 30,000 patients will not have been diagnosed. Even if the multiplication of pulmonary scanners to confirm coronavirus infections could allow the detection of certain tumors.

A "very worrying" situation for Axel Kahn, who points to two consequences: taking care of patients too late and the risk of saturation during normal resumption of activities.

"If the postponements of control exams, chemotherapy, radiotherapy, scheduled surgical operations, you add all the late screenings, we risk a very big traffic jam", he warns.

Another consequence is the interruption of treatment. In addition to deprogramming by hospitals, some patients - cancer being an additional risk factor against Covid - preferred to "stay very cautiously confined to protect themselves", notes Eric Solary, president of the scientific council of the ARC foundation for research on the cancer. "We must quickly resume treatment."

A prepublication study by British researchers, coordinated by Professor Clare Turnbull of the Cancer Research Institute in London and put online at the end of April, looks specifically at these different questions.

- Decreased survival -

According to their models, survival at six months could be reduced by 30% by "even a modest delay" in surgical management for certain aggressive cancers in stage 2 (bladder, lung, stomach, for example). Survival at three months would be reduced by 17%.

"In the next 3 to 24 months, the first priority should be to avoid delays in cancer surgery. (...) In the short term, to avoid the cascading effects, the immediate mobilization of additional resources is necessary to absorb the delay in the first months of the pandemic in terms of detection and surgical procedures ", warn these specialists.

Another concern is the possible coronavirus / cancer interactions. The CRA has launched an appeal to fund research projects on these issues (70 are already in the running).

It is a question of "measuring the impacts on care and seeing how to quickly help clinicians to adapt treatments, how to use drugs in this context that we know little about," explains Professor Solary.

For all these specialists, it is urgent to get back on track and relaunch the fight, even though Axel Kahn regrets a "collapse of donations" since the start of the pandemic.

"Cancer kills 150,000 people every year. A year ago, this year, next year ... This year alone, the Covid, luckily, will do much less damage."

© 2020 AFP