Background: Available studies on the effect of serum selenium levels on the risk of malignancies show some conflicting results. In this study, we investigated the correlation between serum selenium levels and ovarian cancer occurrence. Methods: 314 women (157 diseased patients and 157 healthy ones) matched in terms of age and BMI were included in the study. The measurements of selenium in the collected blood samples were performed using an ICP mass spectrometer. Univariable and multivariable analyzes were performed to determine the relationship between the factors under the study and the occurrence of ovarian cancer. Results: The mean concentration of selenium was lower among diseased ones than among controls (53.31 μg/L vs. 78.99 μg/L). A decrease in selenium concentration was noticed with the advancement of ovarian cancer. In univariable and multivariable analyzes, a clear relationship between low selenium concentration and the occurrence of ovarian cancer was found (35.3 (95% CI: 11.2–111; p < 0.001) and 45.8 (95% CI: 12.8–164; p < 0.001)). Conclusion: The studied patients with ovarian cancer are characterized by statistically significant lower serum selenium levels than patients from the control group. Among the study group, a decrease in selenium concentration was observed with an increase in the FIGO stage. The determination of the role of selenium as a prophylactic factor in ovarian cancer requires further prospective studies.

Background: Micronutrients are important components for the homeostasis of the human body. The studies available in the literature of the subject on their impact on the risk of population diseases, including malignant neoplasms, are ambiguous. In this paper, the relationship between Cu and Zn serum levels and the occurrence of endometrial cancer have been analyzed. Methods: 306 patients (153 test group and 153 control group) matched for age were analyzed for Cu and Zn levels. Microelements levels were determined for sera collected during the hospitalization of patients by means of an inductively coupled plasma mass spectrometry. In addition, the Cu/Zn ratio in the population included in the study was analyzed. Univariable and multivariable analyzes were used to examine the relationship between the factors under study and the incidence of endometrial cancer. Results: Lower levels of elements were observed in the study group compared with the control group (Cu: 959.39 μg/L vs. 1176.42 μg/L, p < 0.001; Zn: 707.05 μg/L vs. 901.67 μg/L, p < 0.001). A statistically significant relationship with the occurrence of endometrial cancer was observed for Cu and Zn. The patients with the lowest Cu level had a significantly higher occurrence of endometrial cancer compared with reference tertile (OR 8.54; p < 0.001). Similarly, compared with the reference tertile, the patients with the lowest Zn levels had a significantly greater incidence of endometrial cancer (OR 15.0; p < 0.001). Conclusion: The results of the study suggest an association of endometrial cancer occurrence with lower Cu and Zn serum levels.

(1) Background: Selenium (Se) and arsenic (As) influence oxidative stress pathways and may jointly affect cancer risk. We investigated whether Se and As status, individually and in combination, are associated with cancer incidence in women with familial breast cancer predisposition. (2) Methods: In this multicenter prospective study, 6134 BRCA1-negative women aged ≥40 years with hereditary breast cancer predisposition were recruited from 16 genetic clinics in Poland. Blood Se and As concentrations were measured repeatedly during follow-up (6–60 months). Primary analyses evaluated cancer risk across combined Se and As strata within a predefined optimal Se range (98–108 µg/L), including analyses stratified by CAT rs1001179 genotype. Exploratory analyses assessed a composite Risk Index (RI = Se + As × 50). Associations with incident cancer were examined using multivariable Cox regression models. (3) Results: Among 6134 participants, 4847 (79.0%) completed follow-up. The lowest cancer risk was observed in women with Se concentrations of 98–108 µg/L and As concentrations of 0.57–0.75 µg/L. Compared with women with As concentrations >1.07 µg/L, this subgroup showed a lower cancer hazard (HR 3.46; 95% CI 1.28–9.32). Associations were stronger when Se, As, and CAT genotype were analyzed jointly (HR 4.74; 95% CI 1.44–15.53). The RI was also associated with cancer risk (HR 4.51; 95% CI 1.72–11.83). (4) Conclusions: Cancer risk varied according to combined selenium and arsenic status. Stronger associations observed after CAT stratification support a potential role for oxidative stress–related gene–environment interactions in cancer susceptibility.