[Role of sodium selenite as an adjuvant in radiotherapy of rectal carcinoma].

BACKGROUND

In various epidemiologic studies an association of low selenium blood levels and reduced glutathione peroxidase with an increased risk of cancer incidence was described. The antitumoral therapy and a suboptimal nutrition could intensify this deficiency. Every reduction of disease related and therapeutic caused symptoms may improve life quality.

APPLICATION

We report our preliminary experiences in the adjuvant radiochemotherapy of advanced rectal cancer (UICC II/III) corresponding to the NCl recommendation. An oral selenium supplementation was carried out with 2000 micrograms Na2SeO3 after every course of fluorouracil chemotherapy and daily 400 micrograms Na2SeO3 after irradiation of tumor region and lymph nodes. A weekly life quality assessment was explored with special interest in diarrhea, dysurie, pain, appetite, nausea and emesis.

CONCLUSION

Damages to normal tissue specially to DNA enzymes and membranes caused by free radicals is one mechanism in tumorgenesis, tumor progression and therapeutic consequence. A radioprotective effect of selenium is verified by in vitro and in vivo data. Our data show that oral selenium intake in rectal cancer patients is easily tolerated with no side effects. Improving life quality and secondary cancer prevention with supplementation of selenium has to be proven in prospective randomized studies.