title: [Effect of antioxidant supplementation over oxidative stress and quality of life in cervical cancer].
abstract: BACKGROUND
  Mexico has a high rate of cervical cancer which represents an important public health issue. The treatment for this disease depends on the extension of the tumor; for the initial stages surgery is recommended, and for locally advanced tumors, a combination of chemotherapy and radiotherapy is used. All this process affects natural antioxidant consumption and Quality of Life (QoL).
  
  
  OBJECTIVE
  To find out the effect that supplementation with antioxidants (β-carotene, vitamin C y vitamin E) has on oxidative stress, and quality of life in patient diagnosed with cervical cancer during treatments with cisplatin and radiotherapy.
  
  
  METHODS
  We conducted a randomized, blind clinical trial in women with cervical cancer whose antineoplasic treatment was radiotherapy in and radiotherapy with cisplatin. Patients were randomly assigned to receive antioxidant therapy or a placebo. Plasma concentrations of malondialdehyde (MDA), free carbonyls, dityrosines, and carbonyl/protein rate in two different moments, before oncologic therapy, and after finishing oncology treatment, we also evaluated food consumption by using a validated food frequency questionnaire and a QOL questionnaire before treatment and after it was over. The effect of the antioxidant treatment was assessed by the use t-student test for independent and paired samples, as well as frequencies and X² for categorical variables.
  
  
  RESULTS
  We evaluated 103 patients who were randomly assigned to receive treatment with antioxidants 49 (47.60%) and placebo 54 (52.40%). We did not find statistically significant differences in food or antioxidant consumption according to the food frequency questionnaires. Most of the patients consumed more energy than needed to meet their requirement, but they did not consume enough of most of the antioxidants according to the Recommended Dailiy Allowance (RDA) recommendation. Serum levels of plasma free carbonyls and carbonil/mg of protein ratio were statistically significant (p < 0.009) which shows protein protection regarding oxidative stress in the supplemented group, this information was similar to the one found in the QOL questionnaire, which showed that Global QOL was better in the supplemented group (p < 0.025). Most of the patients had lower α-tocopherol and retinol plasma levels than the recommended values.
  
  
  CONCLUSIONS
  Antioxidant supplementation showed to be effective in reducing oxidative stress in proteins, but it did not on food ingestion, patients did not meet their antioxidants requirement in their diets, in spite of an excess in energy consumption. Antioxidant plasma levels in most of the patients were lower than normal. QoL score was better in the supplemented group.
authors.affiliation: Servicio de Oncología y Dirección de Investigación, Hospital General de México, México. fuchsvanessa@yahoo.com
authors.forename: V
authors.initials: V
authors.lastname: Fuchs-Tarlovsky
authors.forename: M
authors.initials: M
authors.lastname: Bejarano-Rosales
authors.forename: G
authors.initials: G
authors.lastname: Gutiérrez-Salmeán
authors.forename: M A
authors.initials: MA
authors.lastname: Casillas
authors.forename: J C
authors.initials: JC
authors.lastname: López-Alvarenga
authors.forename: G M
authors.initials: GM
authors.lastname: Ceballos-Reyes
mesh_terms: D000328:Adult; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use; D000975:Antioxidants / Q000378:metabolism / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D004032:Diet; D019587:Dietary Supplements; D004311:Double-Blind Method; D004435:Eating; D005260:Female; D006801:Humans; D008800:Mexico; D008875:Middle Aged; D018673:Nutrition Policy; D018384:Oxidative Stress / Q000187:drug effects*; D011788:Quality of Life; D011878:Radiotherapy / Q000009:adverse effects; D002583:Uterine Cervical Neoplasms / Q000523:psychology* / Q000628:therapy
chemical_list: D000970:Antineoplastic Agents; D000975:Antioxidants