Self-organizing maps classification of epidemiological data and toenail selenium content monitored on cancer and healthy patients from Poland

Abstract

This paper deals with epidemiological multivariate statistical analysis of cancer and health patients from Pomeranian and Lubuskie Voivodships, Poland. The anthropometric and epidemiologic data include 8 parameters: toenail selenium concentration, sex, age, body mass index (BMI), smoking status, taking of Se supplements, health state, and family history of cancer. The self-organizing maps (SOM) are used for simultaneous classification of parameters and patients with relation to cancer diagnosis. Three different patterns (groups) of patients with cancer diagnosis are outlined: (i) older, smoking men with low toenail selenium concentration; (ii) older smoking women with family relation to cancer and toenail selenium deficiency; (iii) middle, aged nonsmokers with high level of selenium toenail concentration. The simultaneous classification of parameters and patients makes it possible to determine discriminating parameters for each pattern and relations between parameters. The relation of each parameter to cancer disease is discussed as special attention is paid to toenail selenium deficiency. More than 80% of patients with cancer diagnosis possess toenail selenium deficiency, accompanied by old age and smoking.