Discussion:
Prostate cancer is the most common cancer in men [11]. Since the
beginning of screening for prostate cancer with serum PSA, we have seen
a significant decline in prostate cancer mortality [12].
A systematic analysis suggested that up to 60% of prostate cancers
diagnosed in contemporary studies can be safely observed without a need
for immediate intervention [13]. However, 20% to 30% of men who
are diagnosed with prostate cancer are found to have high-grade disease
at presentation [14]. Diagnosis should focus on detection of
aggressive tumors, that are more likely to progress to metastatic
disease and death, and not the indolent ones.
The 4K ® scores test is a relatively new blood test that identifies the
risk of aggressive cancer and has a role as an initial test before
performing prostate biopsies in men with an elevated PSA level or an
abnormal digital rectal examination result, or after a previous negative
prostate biopsy with persistently elevated PSA level. The test result is
a personalized positive predictive value of finding Gleason score ≥ 7
cancer on biopsy of the prostate. This provides the patient and
physician with quantitative information to aid in clinical decision
making regarding performing prostate biopsies.
The COVID-19 era in general had a major effect on health-care related
issues such as allocating medical resources to cope with COVID and its
implications, delaying or postponing non-emergent diagnostic procedures
and even limited availability of primary care providers, not to mention
expert consultation
This study is intended to examine the extent of the effect during the
first quarantine period of COVID-19 pandemic on performing 4K® blood
tests in Israel. We found that the number of tests performed during the
study period decreased significantly by about 37% compared to the
corresponding period the year before. This fact is consistent with that
described in the literature on reduction in malignancy-related tests
during the COVID-19 period. One of the subjects being investigated
recently is the risk of late diagnosis and mortality from
life-threatening diseases in general [15] and cancer in particular
[16]. These studies found an increased risk of morbidity and
mortality from serious diseases due to neglect and reduction in
follow-up and late diagnosis of malignant diseases during this period.
Another component is the psychological consequences of living during a
pandemic that causes anxiety and seclusion that have a negative effect
on the diagnosis and treatment of patients with serious illnesses
[17].
Our study found a significant difference between the study and control
groups in the percentage of tests indicating a high-risk (4K® score
above 20%) and a very high-risk (4K ® score above 33%) for clinically
significant prostate cancer.
A reasonable explanation for these differences would have been an
increased PSA levels during screening, which incited both the referring
physician and the patient to perform the 4K® test. However, no
significant difference in PSA level was found between the study group
and the control group. The mean age was not significantly different
between the groups but the ratio of patients 65 years or younger out of
the total subjects in the study period (211/450=0.47) was higher
relative to their ratio in the control group (259/721=0.36). This may be
because older patients tended to be more isolated and secluded during
the first quarantine period included in the study period.
The patients’ age was found to be an influencing factor on higher 4K ®
scores during the study period, even in multivariable analysis. During
the study period, more patients aged 65 or younger with high 4K® scores
were found compared to the corresponding period the year before. One
possible explanation is that 4K ® tests were performed instead of MRI
imaging that were canceled or postponed due to the pandemic working
schedule [18].
This is the first study to address the implications of this challenging
era on the diagnosis of prostate cancer using biological markers.
The strengths of the study are a uniform database with a large number of
tests performed in one central laboratory.
The limitations of the study are a relatively short period of time
during the pandemic period taken as the study period as well as the lack
of the actual biopsy results.
Extensive research with a larger database is required to validate the
research findings.