dinoprost and Thyroid-Neoplasms

The objective of this study, in addition to confirming that therapy with 131I causes oxidative stress, was to evaluate the effect of supplementation with vitamins C and E and selenium on this phenomenon by measuring plasma 8-epi-PGF2a, a marker of lipid peroxidation.. Forty patients with thyroid cancer submitted to thyroidectomy, who received 3.7 GBq 131I after levothyroxine withdrawal, were selected; 20 patients did not receive (control group) and 20 patients received (intervention group) daily supplementation consisting of 2000 mg vitamin C, 1000 mg vitamin E and 400 µg selenium for 21 days before 131I. Plasma 8-epi-PGF2a was measured immediately before and 2 and 7 days after 131I.. A significant increase in plasma 8-epi-PGF2a after 131I was observed in the two groups. The concentrations of 8-epi-PGF2α were significantly higher in the control group before and 2 and 7 days after 131I. The percentage of patients with elevated 8-epi-PGF2α was also significantly higher in the control group before and after 131I. Furthermore, the increase (percent) in 8-epi-PGF2α was significantly greater in the control group (average of 112.3% versus 56.3%). Only two patients (10%) reported side effects during supplementation.. Ablation with 131I causes oxidative stress which can be minimized by the use of antioxidants.

Topics: Adult; Analysis of Variance; Antioxidants; Ascorbic Acid; Carcinoma; Dietary Supplements; Dinoprost; Female; Humans; Iodine Radioisotopes; Lipid Peroxidation; Male; Middle Aged; Oxidative Stress; Prospective Studies; Reproducibility of Results; Selenium; Thyroid Neoplasms; Thyroidectomy; Thyroxine; Time Factors; Treatment Outcome; Vitamin E; Young Adult

131I is the treatment of choice for differentiated thyroid cancer and hyperthyroidism. A relationship between low-density lipoprotein oxidation and radioiodine therapy-related side effects, consequently inducing increased formation of 8-epi-prostaglandin F(2 alpha) (PGF(2 alpha)) in situ, has recently been reported by several investigators. Isoprostanes, among them 8-epi-PGF(2 alpha), have been associated with increased oxidation injury due to various pathologic conditions in vivo. The aim of this study was to investigate the possible induction of oxidative stress as a consequence of (131)I therapy.. 8-epi-PGF(2 alpha) was examined in plasma, serum, and urine in 42 patients undergoing radioiodine treatment of hyperthyroidism or thyroid cancer. The 8-epi-PGF(2 alpha) levels were analyzed daily for 1 wk and thereafter at different points up to 12 wk after treatment.. The isoprostane levels showed an increase after application of radioiodine in all investigated compartments. The effect was significantly higher and longer lasting after higher-activity therapy (2,960 or 7,400 MBq) than after lower-activity therapy (185 or 740 MBq).. These findings document a significant, dose-dependent in vivo oxidation injury as a consequence of therapeutic radioiodine application to the salivary gland.

Topics: Adult; Aged; Dinoprost; Dose-Response Relationship, Radiation; Female; Humans; Hyperthyroidism; Iodine Radioisotopes; Male; Middle Aged; Oxidative Stress; Thyroid Neoplasms