The COVID-19 pandemic is not only a problem in terms of intensive care medicine, but could lead to further collateral damage, according to pathologists. Delayed or missed cancer diagnoses put lives at risk as well. An audit study from Italy, one of the European countries most affected in the first wave of corona in 2020, provides the first robust data.
In their study, researchers evaluated the number of pathologically confirmed initial diagnoses of various tumors in weeks 11 to 20 of 2018, 2019 and 2020. They were interested in the most common tumor entities in Italy: breast, prostate, lung, colon and bladder cancer, stomach cancer, non-Hodgkin's lymphoma, liver cancer and melanoma.
The result of the study is clear and demonstrates that the problem of collateral damage in oncology is now reaching significant levels for patient health. According to the study, in the corona year 2020, the number of new diagnoses for cancer in general fell by -39% compared to the same periods of the previous year.
For prostate cancer, the number of new diagnoses decreased by -75%, for bladder cancer by -66% and for colorectal cancer by -62%. For non-Hodgkin's lymphoma, there were still -37% fewer new diagnoses, and for breast cancer -26% fewer in 2020.
At the same time, however, the risk of later cancer diagnoses in an already advanced stage increased. Thus, the number of new diagnoses of metastases generally increased by +79%. Delayed or late tumor diagnoses also increase mortality and can thus significantly worsen the outcome for the patients concerned.
The authors of the study discuss at the end of their short article that the slump in diagnoses is to be evaluated quite differently for the individual tumor entities. For example, despite the 75% drop in initial diagnoses of prostate cancer, serious collateral damage is not to be expected. A recent study from 2020 showed that even 12-month delays in the treatment of prostate cancer did not lead to a significantly worse clinical outcome.
However, the situation is different for colorectal cancer. From an earlier study from Taiwan, it is known that the risk of dying from colorectal cancer, for example, increases with time from diagnosis to the start of treatment. With an interval between 31 and 150 days, the mortality risk is increased by 51% (HR = 1.51), whereas with delays beyond 151 days it is already 64% (HR = 1.64).
This illustrates once again how important regular colorectal cancer screening is in order to be able to diagnose and treat cancers at an early stage. In practice, patients should therefore continue to be advised on cancer screening even during corona times and receive an appropriate offer. For bowel cancer or even colorectal cancer, this primarily means a Fecal Immunochemical Test (FIT) and/or colonoscopy - considering the numbers, this can only have a positive effect on patients' health in the long run.
Reference:
De Vincentiis L et al, Cancer diagnostic rates during the 2020 'lockdown', due to COVID-19 pandemic, compared with the 2018-2019: an audit study from cellular pathology. J Clin Pathol 2021; 74: 187-189. doi:10.1136/jclinpath-2020-206833