Oncologist-patient conflict regarding imatinib-induced pigmentation: A case report and literature review

Abstract

Abstract: The tyrosine kinase inhibitor imatinib mesylate is well known for inhibiting melanocyte growth, which results in hypopigmentation, but here, we present a case report of imatinib-induced hyperpigmentation in a 42-year-old female belonging to a lower-middle socioeconomic status and a resident of a local village. The case report is unique as it provides valuable insights into clinical characteristics, diagnostic challenges, and therapeutic considerations for imatinib-induced hyperpigmentation which may contribute to existing literature on this rare and challenging entity, particularly in chronic myeloid leukemia (CML). The patient presented to the radiotherapy outpatient department 2.5 years ago with chief complaints of a single episode of oral bleeding and abdominal pain for 15 days. Blood investigations revealed a high total leukocyte count, platelet count, and Hb-10.5 suggestive of some myeloproliferative disorder for which the patient was advised bone marrow aspiration biopsy for confirmation. Biopsy findings are consistent with CML. That is how we reached a diagnosis of CML. Imatinib therapy was started with a dose of 400 mg OD orally daily. She was continued on the same dose. As the disease of the patient was partially responding to this dose and the patient still had on-and-off complaints along with abnormal blood parameters, the dose was gradually increased to 600 mg od orally, but after 2 months of this dose, hyperpigmentation on the cheeks gradually appeared which slowly increased to involving whole of the face. Clinical findings revealed brownish hyperpigmented macules involving the forehead, nose, malar, and mandibular areas. There was no significant family history and no history of similar complaints in the past. There was no history of an allergy to any drug. Dermoscopy showed an irregular dark brown pigmentation network in a pseudoreticular pattern, along with hypopigmented areas in between. Based on the clinical findings and dermoscopy results, the patient was diagnosed with imatinib-induced melasma-like pigmentation. Therapeutic intervention was done. The patient was initiated on topical depigmenting agents, sunscreen, and topical corticosteroids to address the hyperpigmentation, coupled with strict photoprotective measures for comprehensive management. The patient is currently under our care, continuing imatinib therapy with us at the same dose as the patient is having a good response to primary disease at this dose and attending regular follow-up appointments at the dermatology clinic showing symptomatic improvement. We conclude that informing the patient about the possibility of this side effect can increase compliance to therapy. Further insight into the mechanisms of the pigmentary alterations caused by this drug is required for better treatment/prevention of this manifestation.