Multicenter, phase 3 trial comparing selenium supplementation with observation in gynecologic radiation oncology.
OBJECTIVE
We assessed whether adjuvant supplementation with selenium improves the selenium status and reduces side effects of patients treated by radiotherapy (RT) for cervical and uterine cancer.


METHODS
Whole-blood selenium concentrations were measured in patients with cervical cancer (n = 11) and uterine cancer (n = 70) after surgical treatment, during RT, at the end of RT, and 6 weeks after RT. Patients with initial selenium concentrations of less than 84μg/L were randomized before RT either to receive 500 μg of selenium (in the form of sodium selenite [selenase, biosyn Arzneimittel GmbH, Fellbach, Germany]) by mouth on the days of RT and 300 μg of selenium on the days without RT or to receive no supplement during RT. The primary endpoint of this multicenter Phase 3 study was to assess the efficiency of selenium supplementation during RT; the secondary endpoint was to decrease radiation-induced diarrhea and other RT-dependent side effects.


RESULTS
A total of 81 patients were randomized. We enrolled 39 in the selenium group (SG) and 42 in the control group (CG). Selenium levels did not differ between the SG and CG upon study initiation but were significantly higher in the SG at the end of RT. The actuarial incidence of diarrhea of Grade 2 or higher according to Common Toxicity Criteria (version 2) in the SG was 20.5% compared with 44.5% in the CG (p = 0.04). Other blood parameters, Eastern Cooperative Oncology Group performance status, and self-reported quality of life were not different between the groups.


CONCLUSIONS
Selenium supplementation during RT is effective in improving blood selenium status in selenium-deficient cervical and uterine cancer patients and reduces the number of episodes and severity of RT-induced diarrhea.
Muecke
Ralph
R
Department of Radiotherapy, Lippe Hospital, Lemgo, Germany.
Schomburg
Lutz
L
Glatzel
Michael
M
Berndt-Skorka
Regina
R
Baaske
Dieter
D
Reichl
Berthold
B
Buentzel
Jens
J
Kundt
Guenter
G
Prott
Franz J
FJ
Devries
Alexander
A
Stoll
Guenther
G
Kisters
Klaus
K
Bruns
Frank
F
Schaefer
Ulrich
U
Willich
Norman
N
Micke
Oliver
O
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003967:Diarrhea / Q000209:etiology / Q000517:prevention & control; D005260:Female; D005858:Germany; D006801:Humans; D008875:Middle Aged; D011878:Radiotherapy / Q000009:adverse effects; D012643:Selenium / Q000097:blood* / Q000172:deficiency; D018038:Sodium Selenite / Q000008:administration & dosage; D013997:Time Factors; D002583:Uterine Cervical Neoplasms / Q000097:blood / Q000401:mortality / Q000532:radiotherapy / Q000601:surgery; D014594:Uterine Neoplasms / Q000097:blood* / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery
D012643:Selenium; D018038:Sodium Selenite