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). CONCLUSION: 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.

Risk assessment in myelodysplastic syndromes: value of clinical, hematologic and bone marrow histologic findings at presentation.

We analyzed the prognostic value of clinical, hematologic and bone marrow (BM) histologic findings at presentation in 94 patients with myelodysplastic syndromes (MDS) (28 RA; 2 RARS; 34 RAEB; 6 CMML; 24 RAEB-t). With survival as the dependent variable, stepwise multivariate analysis indicated as the prognostically most important factors among the MDS taken as a whole: latency from the first symptoms to diagnosis, age, and percentage of BM blasts. In each main MDS group the most unfavorable initial characteristics were: 1) low Hb, no macro-megaloblastosis, male sex for RA/RARS; 2) low Hb and low platelet levels for RAEB/CMML; 3) granuloblastic hyperplasia and high BM blastosis for RAEB-t. Of the BM histologic parameters, only the percentage of blasts had significant prognostic value. Histologic assessment of BM blastosis, however, did not differ statistically from that based on cytologic examination of BM smears, so that marrow histology seemed not essential for initial prognostic assessment in MDS patients. The finding of abnormal localization of immature precursors (ALIP) in BM biopsies was associated with a negative trend without reaching statistical significance. Using four objective parameters of proven significance (age, Hb, platelets, and BM blasts) we devised a staging system of immediate clinical utility for prognostic stratification and risk-adapted therapeutic choices.

Quantitative assessment of erythropoiesis in haemolytic disease.

Erythrokinetic parameters were estimated in 21 patients suffering from haemolytic disease using a mathematical model of iron kinetics. A proper definition of radioiron reflux from red cells to the plasma proved to be essential for an accurate estimate of effective and ineffective erythropoiesis in severe haemolytic conditions. Erythropoietic activity was increased in all the patients, with the marrow capable of sustaining erythropoiesis at about 6 times normal in hereditary spherocytosis and 3 times normal in autoimmune haemolytic anaemia. This proliferative effort was countered by an increase in ineffective erythropoiesis which was especially marked in hereditary spherocytosis.