A long-term time course of colorimetric assessment of the effects of imatinib mesylate on skin pigmentation: a study of five patients.
BACKGROUND
Imatinib mesylate (IM), the first-line treatment of chronic myeloid leukaemia (CML), is a tyrosine kinase inhibitor that targets those proteins involved in BCR-ABL signal transduction in CML, c-kit (KIT) and platelet-derived growth-factor (PDGFR) receptor. The use of IM has been associated with cutaneous reactions. In the last 2 years numerous studies have focused the attention on hypopigmentations, depigmentations and photosensitivity developing after the initiation of IM therapy.


OBJECTIVE
The aim of this study is to evaluate the effects of IM therapy on the skin pigmentation of five patients affected by CML.


METHODS
Skin pigmentation measurements were performed with a Minolta CR-200 Chromameter. results: All the studied patients show the gradual lightening of the skin on unexposed areas over the treatment with IM. In particular, this explorative colorimetric study indicates the association between IM and skin depigmentation with a significant increase of luminance value (L*) (P = 0.001) and a significant decrease of the pigmentation value (b*) (P = 0.028).


CONCLUSIONS
Even if we do not know the clinical significance of the skin depigmentation caused by IM, the regulatory role of KIT and its ligand stem cell factor in melanocyte development and survival seems to suggest an objective mechanism of action for IM in the pathogenesis of this cutaneous depigmentation.
Brazzelli
V
V
Department of Human and Hereditary Pathology, Institute of Dermatology, University of Pavia, IRCCS-Policlinico S. Matteo, Piazza C. Golgi 2, 27100 Pavia, Italy. v.brazzelli@libero.it
Prestinari
F
F
Barbagallo
T
T
Rona
C
C
Orlandi
E
E
Passamonti
F
F
Locatelli
F
F
Zecca
M
M
Villani
S
S
Borroni
G
G
D000293:Adolescent; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001549:Benzamides; D003124:Colorimetry; D005260:Female; D006801:Humans; D000068877:Imatinib Mesylate; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000627:therapeutic use*; D011743:Pyrimidines / Q000627:therapeutic use*; D012880:Skin Pigmentation / Q000187:drug effects*; D018709:Statistics, Nonparametric
D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate