Introduction:
Whether there is a protective or stimulating effect of atopy on the risk of neoplastic disease is an interesting question. Studies that have analyzed the matter to date have proposed various explanations for such an effect. In this study, the prevalence of neoplastic diseases in patients with confirmed atopic diseases compared with a control non-atopic group was analyzed.

Material and methods:
A total of 1451 patients with atopic disease and 1389 control subjects over 35 years of age received a physical examination, a skin-prick test and measurement of IgEs specific to common inhalant allergens. A medical history based on an original questionnaire and analysis of family history for the possible occurrence of neoplastic diseases and allergies were performed. Additionally, tumor markers AFP, CEA, SCC, PSA, Ca15.3, Ca19-9, Ca125, HCG, and CYFRA 21-1 were measured in serum.

Results:
The results confirmed no significant difference in the prevalence of most analyzed neoplasms between the groups. Chronic lymphocytic leukemia and chronic myelogenous leukemia were significantly less common in the study group. A negative correlation between the concentration of total IgE in serum and the probability of neoplasm diagnosis in the study group was noted. A higher concentration of serum marker CYFRA 21-1, but without clinical manifestation in patients with atopic disease was observed.

Conclusions:
The occurrence of neoplastic diseases is slightly lower in patients with atopic diseases than in the control group without allergies. There were no significant differences in the analyzed serum tumor markers between the groups.