Skin Changes on Continued Imatinib Therapy in Patients with Ph+ CML.

We reported the skin changes (generalized hypopigmentation) caused by imatinib mesylate (IM) in patients with Ph+ CML or GIST (EHA 2004 & ASH 2004). Subsequent reports from MDACC confirmed such findings. Such changes could be different and more profound among the brown skinned people of India. A cohort of 200 Ph+ CML patients at various phases of the disease receiving IM in a daily dose of 300 mg - 800 mg (children 200 mg daily) were studied over a median period of 14 months (range 5 – 72 months). Skin changes of any kind or severity were noted in 120 (60%) patients. Hypopigmentation alone (usually generalized) was seen in 75 patients (32.5%), combined hypopigmentation and hyperpigmentation in 39 (19.5%), hypopigmentation + extreme thinning of the skin in 3 (1.5%) and the classical skin rash of grade 3/4 in 2 (1%). Skin changes occurred at all dose levels. Characteristically the hyperpigmented patches were localized to the facial area over the forehead and/or in a butterfly pattern across the malar areas and bridge of the nose. IM dose was not modified among patients with pigment changes alone. IM causes dose-independent hypo- or hyperpigmentation of the skin in a significant number of Indian patients with Ph+ CML. This apparently happens due to modified melanin metabolism through the tyrosine pathway. Some of these changes (hyperpigmentation and extreme thinning) are bothersome from cosmetic viewpoint.