Serum Alpha-tocopherol, Retinol and Neopterin during Paclitaxel/Carboplatin Chemotherapy

Background: Disorders of antioxidant balance are considered to be involved in the toxicity associated with radiotherapy or chemotherapy. Patients and Methods: Serum alpha-tocopherol and retinol were determined, by high performance liquid chromatography, before and during therapy with a combination of paclitaxel and carboplatin in 28 patients with breast and ovarian cancer. Serum neopterin and cholesterol were measured using a radioimmunoassay and enzymatic colorimetric method, respectively. Results: Compared to pretreatment concentrations, a significant increase was observed in serum alpha-tocopherol and retinol concentrations during therapy that was associated with decreased serum neopterin concentrations. Serum alpha-tocopherol concentrations were significantly higher during therapy in patients who did not experience serious toxicity. Conclusion: An increase in alpha-tocopherol and retinol during therapy with combination paclitaxel/carboplatin may be explained by inhibition of systemic immune activation secondary to control of the tumor with effective chemotherapy. Lower alpha-tocopherol concentrations were associated with the toxicity of therapy.