A case series of imatinib-induced generalized hypopigmentation and progression of existing acquired dermal melanocytosis

Abstract

Imatinib mesylate is a tyrosine kinase inhibitor used in the treatment of oncological conditions, including chronic myeloid leukemia and gastrointestinal stromal tumors. The most frequent dermatological side effect reported is pigmentary abnormalities. We report a case series of three Asian Chinese females with preexisting acquired dermal melanocytosis that progressed after initiation of imatinib treatment, and concurrently developed generalized hypopigmentation of the skin. All three patients had similar histological findings on skin biopsy. It is postulated that the KIT/SCF pathway has a central role in the pathogenetic mechanism. Therefore, it is important for physicians to be aware of this potential side effect of paradoxical pigmentation in patients treated with imatinib.

Imatinib‐induced eruptive nevi

“…Imatinib mesylate is a tyrosine kinase inhibitor (TKI) used to treat chronic myeloid leukaemia and gastrointestinal stromal tumours among other cancers. Dermatologic skin manifestations of imatinib are commonly reported and include pigmentary abnormalities such as hyper‐ and hypopigmentation 1 . Here, we present the first case of eruptive melanocytic nevi (EMN) induced by imatinib, a phenomenon previously reported with other TKIs.…”

Imatinib Induced Hypopigmentation and Neutropenia in a Patient with Gastric Gastrointestinal Stromal Tumor

“…However, skin and hair color changes related to imatinib for GIST tumor are relatively rare [8]. On literature review, there were only 3 cases found specifically of hypopigmentation with imatinib used for GIST tumors in patients without germline KIT mutations causing familial GIST [9,10,15]. Results are summarized in Table 2.…”

Imatinib Mesylate-Induced Acquired Dermal Melanocytosis and Acquired Bilateral Nevus of Ota-Like Macules

“…Imatinib mesylate, a tyrosine kinase inhibitor, is used for treatment of oncological conditions, such as chronic myeloid leukemia (CML) and gastrointestinal stromal tumor 1 . It inhibits tyrosine kinase encoded by the bcr-abl, c-kit, and platelet-derived growth factor receptor oncogenes 2 3 .…”

“…ABNOM, a kind of ADM, is characterized by symmetrical blue-brown macules, most frequently involving facial lesions in Asian women with histopathological findings of irregularly-shaped bipolar melanocytes dispersed in the papillary and mid dermis, particularly in the subpapillary dermis. These dormant melanocytes could be later reactivated by various factors like inflammation, local trauma, sunlight, drugs, or hormonal stimulations 1 2 .…”

“…The mechanisms of imatinib-induced hyperpigmentation have been hypothesized that imatinib could have different target effects on immature and mature melanocytes, and that KIT and its ligand stem cell factor (SCF) play a critical role in the pathogenesis 1 . Imatinib-induced KIT/SCF blockage may cause epidermal depigmentation in mature melanocytes while influencing immature melanocytes to differentiate to produce melanin pigment causing hyperpigmentation 1 .…”