Serum iron levels increased by cancer chemotherapy correlate the chemotherapy-induced nausea and vomiting.

Background: The pathogenesis of chemotherapy-induced nausea and vomiting (CINV) is not fully elucidated. We hypothesized that serum iron levels may be associated with CINV because symptoms of iron poisoning resemble the adverse effects of chemotherapy.

Methods: Patients with lung cancer undergoing chemotherapy were included in this retrospective study where serum iron level, unsaturated iron-binding capacity (UIBC), total iron-binding capacity, and ferritin were available prior to and on days 2 and 8 of chemotherapy.

Results: Fifty-two patients were analyzed. Iron levels on day 2 were markedly increased in patients receiving highly emetogenic chemotherapy (HEC, 231.0 ± 45.0 µg/dl) and moderately emetogenic chemotherapy (MEC, 226.6 ± 44.2 µg/dl), and mildly increased in patients receiving low emetogenic chemotherapy (LEC, 104 ± 51.4 µg/dl). Significant differences in iron levels on day 2 were observed between the HEC and LEC (P = 0.002) and MEC and LEC (P = 0.0007) groups. UIBC levels decreased on day 2 (18.0 ± 17.5 µg/dl in HEC, 20.4 ± 46.8 µg/dl in MEC, and 123.9 ± 65.9 µg/dl in LEC). There were significant differences in UIBC on days 2 between the HEC and LEC (P = 0.0005) and MEC and LEC (P = 0.0015) groups. No significant changes in these parameters were observed in a minimal risk group.

Conclusions: Iron levels increased according to the emetogenic risk. Accompanied by a markedly increased iron level, non-transferrin bound iron, a highly cytotoxic form of iron, may be present in the serum. Iron removal with an iron-chelating agent may represent a novel antiemetic therapy in patients undergoing chemotherapy.