Micronucleus evaluation in mitogen-stimulated lymphocytes of narrow-band (311 nm TL01) UVB-treated patients.
BACKGROUND
Narrow-band UVB (311 nm) lamps (TL01) are being increasingly used for phototherapy of psoriasis and other dermatoses, for their excellent effect compared with broad-band UVB sources and photochemotherapy. It is acknowledged that the TL01 lamp is probably two to three times more carcinogenic per minimum erythema dose than broad-band UVB, but the cumulative dose is considerably less than broadband UVB sources. Micronucleus (MN) test is used to detect both clastogenic (breaking) and aneugenic (abnormal segregation) effect of physical/chemical agents on chromosomes. The aim of this study is to evaluate MN frequencies in mitogen-stimulated lymphocytes of narrow-band UVB-treated patients.


METHODS
Frequency of micronuclei in 72 h cultivated/mitogen-stimulated lymphocytes of 36 patients (age 7-73 years, mean+/-SD: 25.33+/-18.54) have been evaluated at pretreatment and after 20, 40, 60 sessions of narrowband UVB treatment.


RESULTS
While the beginning MN frequency +/-SD (%) was 1.07+/-0.63, it increased to 1.47+/-0.92, 1.47+/- 0.77, 1.41+/-0.31 corresponding, respectively, to 20, 40, 60 sessions. These sessions reciprocally correspond to 0.85+/-0.23, 2.97+/-0.72, 5.68+/-1.46 J/cm(2) doses of narrow-band UVB. Difference of MN frequency was statistically significant (P=0.002). Significant differences have been observed between the initial MN frequency and after that of 20, 40, 60 sessions (P=0.001, 0.004, 0.002, respectively).


CONCLUSIONS
The results of this study show that narrow-band UVB treatment causes a detectable chromosome damaging effect.
Ferahbas
Ayten
A
Department of Dermatology, Medical Faculty, Erciyes University, TR-3809, Kayseri, Turkey. ferabas@erciyes.edu.tr
Donmez-Altuntas
Hamiyet
H
Hamurcu
Zuhal
Z
Aktas
Ekrem
E
Utas
Serap
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D016014:Linear Models; D008214:Lymphocytes / Q000528:radiation effects*; D008297:Male; D015162:Micronucleus Tests; D008875:Middle Aged; D012871:Skin Diseases / Q000532:radiotherapy; D018709:Statistics, Nonparametric; D014467:Ultraviolet Therapy / Q000009:adverse effects*