Serological Thymidine Kinase1 is a Biomarker for Early Risk of Tumours Progression —Real World Data from a Health Screening Study on a Cohort of 35,365 People

Serological thymidine kinase 1 (STK1p) is a reliable proliferation marker for prognosis, monitoring tumour therapy, and relapse. Here we investigated the use of STK1p in health screening for early detection of pre-malignant and malignant diseases. The investigation was based on 35,365 participants in four independent health screening studies in China during 2005–2019 based on Real World Data. All participants were clinically examined. The concentration of STK1p was determined by a sensitive chemiluminescent dot blot ECL assay. The ROC-value of the STK1p assay was 0.96. At a cut-off STK1p value of 2.0 pM, the likelihood (+) value was 236.5, and the sensitivity and the specificity were 0.78 and 0.99, respectively. The relative number of city-dwelling people with elevated STK1p values (>2.0 pM) was 0.8% (198/26,484), while the corresponding value for the group of oil-field workers was 5.8% (514/8,355). The latter group expressed significantly higher frequency of refractory anaemia, fatty liver, and obesity, compared to the city dwellers, but no cases of breast hyperplasia or prostate hyperplasia were observed. Furthermore, people working in oil drilling/oil transportation showed higher STK1p values and higher frequency of pre-malignancies and benign diseases than people working in the oil-field administration. In the STK1p elevated group of the city-dwelling people, a statistically significantly higher number of people were found to have malignancies, pre-malignancies of all types, moderate/severe type of hyperplasia of breast or prostate, or refractory anaemia, or to be at high risk for hepatitis B, compared to people with low STK1p values (<2.0 pM). No malignancies were found in the STK1p low group. In the elevated STK1p group 85.4% showed diseases linked to a higher risk for pre-/early cancerous progression, compared to 52.4% of those with low STK1p values. Randomly selected people with low STK1p values (n=6,352/26,484) and elevated STK1p values (170/702) that were follow-up for 132 months showed 4 times higher risk to develop malignancies among people with elevated STK1p values, compared to people with low STK1p values. The risk value was calculated from an expected cancer incident rate of 0.2% among the people with low STK1p, based on official cancer statistic in China. We conclude that serological TK1 protein concentration is a reliable marker for risk assessment of pre/early cancerous progression.