[Increase of oxygen free radicals and their derivatives in chemo- and radiation treated neoplasm patients].

BACKGROUND

Radical oxygen species (ROS) are known to mediate cytotoxic anticancer activity by modifying the cellular homeostatic redox balance. The aim of the study is to evaluate whether cancer patients show more ROS after radio/chemotherapy.

METHODS

ROS were evaluated in 32 oncologic untreated patients. Blood samples were collected both before and after the end of radio/chemotherapy. Spectrophotometric detection of ROS was performed by using d-ROMs test (Diacron).

RESULTS

After therapy all patients showed a marked increase in ROS (378 +/- 35 U Carr) compared to values measured before therapy (269 +/- 62 U Carr, p < 0.0001). This result was more evident during the first course of therapy. No significant differences were observed between patients who received radio or chemotherapy.

CONCLUSIONS

In conclusion both radio and chemotherapy induce oxidative stress by increasing radical oxygen species, exceeding the antioxidative capacities of cancer patients. This is useful for therapeutic purposes but may enhance the cytotoxicity induced by therapy.