BI22: A three‐patient case series: methotrexate‐induced nasal septal perforation, mucositis and widespread ulceration

Abstract

history of erythroderma. There was no previous history of skin disease. Biopsy was in keeping with erythrodermic psoriasis. She was started on acitretin 25 mg on alternate days for 10 days, which was then up-titrated to daily dosing. Complete clearance was achieved; she remains on bortezomib and lowdose acitretin with no further relapse. Cutaneous adverse reactions (CARs) with targeted chemotherapy are well recognized. Imatinib – a tyrosine kinase inhibitor used as a first-line treatment for CML – has been reported to cause myriad CARs. They occur in 7–89% of patients in different series, including oedema, maculopapular and pityriasis rosea-like eruptions. Psoriasiform eruptions are rare; in one series of 54 patients treated with imatinib, four were reported to develop a psoriasiform rash, two of whom had pre-existing psoriasis. Cases of imatinib-induced/exacerbated psoriasis (11 reported to date) occurred 1–5 months after starting treatment, were exacerbated in a dose-dependent fashion and resolved with cessation of imatinib, as well as with topical treatment/phototherapy. Imatinib inhibits the secretion of interferon-c by T effector cells with consequent suppression of c-Kit, which may explain the exacerbation of psoriasis in predisposed patients. Bortezomib is a protease inhibitor approved for the treatment of multiple myeloma and mantle cell lymphoma. Its immunomodulatory effects are achieved by suppressing the activation of Toll-like receptors (TLRs) with downstream effects including the inhibition of nuclear factor jB signalling and T helper cell 1 cytokine production. In mouse models with imiquimod-induced psoriasis, topical bortezomib potentiated skin inflammation to the point of necrosis is some mice. This could explain its mechanism in precipitating psoriasis in our patient. To our knowledge, this is the first bortezomib-induced psoriasis to be treated with acitretin. Dermatologists should be alert to the possibility of psoriasis, among other CARs, in patients on novel targeted chemotherapy agents, and that therapy can be continued while simultaneously treating the psoriasis. Acitretin may be a useful therapeutic option in this setting.