All from the Dermatology Clinic, Department of Internal Medicine and Medical Specialties, University of Rome, Italy. Dr. Bottoni also is from University Magna Graecia, Catanzaro, Italy.
The authors report no conflict of interest.
Correspondence: Giovanni Paolino, MD, Clinica Dermatologica, Dipartimento di Medicina Interna e Specialità Mediche, University of Rome, La Sapienza, Viale del Policlinico 155, 00161, Rome, Italy (gio8519@libero.it).
Imatinib mesylate (IM) represents the first-line treatment of patients with chronic myeloid leukemia (CLM) or gastrointestinal stromal tumor (GIST). It presents several side effects. However, less than 10% are nonhematologic including nausea, vomiting, diarrhea, muscle cramps, and cutaneous reactions. The aim of our study was to identify data regarding IM cutaneous adverse effects (AEs) to improve the clinical diagnosis and management of the more frequent side effects. Skin examination should be done before and during IM treatment so that AEs can be diagnosed and treated early with less impact on chemotherapy treatments and on the quality of life of the patient.
The most common cutaneous adverse reactions from imatinib mesylate (IM) are swelling and edema.
Maculopapular rash with pruritus is one of the most common side effects from IM and can be effectively treated with oral or systemic antihistamines.
The onset of periorbital edema requires a complete evaluation of renal function.
References
Imatinib mesylate (IM) represents the first-line treatment of chronic myeloid leukemia (CML) and gastrointestinal stromal tumors (GISTs). Its pharmacological activity is related to a specific action on several tyrosine kinases in different tumors, including Bcr-Abl in CML, c-Kit (CD117) in GIST, and platelet-derived growth factor receptor in dermatofibrosarcoma protuberans.1,2
Imatinib mesylate has been shown to improve progression-free survival and overall survival2; however, it also has several side effects. Among the adverse effects (AEs), less than 10% are nonhematologic, such as nausea, vomiting, diarrhea, muscle cramps, and cutaneous reactions.3,4
We followed patients who were treated with IM for 5 years to identify AEs of therapy.
Methods
The aim of this prospective study was to identify and collect data regarding IM cutaneous side effects so that clinicians can detect AEs early and differentiate them from AEs caused by other medications. All patients were subjected to a median of 5 years’ follow-up. We included all the patients treated with IM and excluded patients who had a history of eczematous dermatitis, psoriasis, renal impairment, or dyshidrosis palmoplantar. Before starting IM, all patients presented for a dermatologic visit. They were subsequently evaluated every 3 months.
The incidence rate was defined as the ratio of patients with cutaneous side effects and the total patients treated with IM. Furthermore, we calculated the ratio between each class of patient with a specific cutaneous manifestation and the entire cohort of patients with cutaneous side effects related to IM.
When necessary, microbiological, serological, and histopathological analyses were performed.
Results
In 60 months, we followed 220 patients treated with IM. Among them, 55 (25%) developed cutaneous side effects (35 males; 20 females). The incidence rate of the patients with cutaneous side effects was 1:4. The median age of the entire cohort was 52.5 years. Fifty patients were being treated for CML and 5 for GISTs. All patients received IM at a dosage of 400 mg daily.
The following skin diseases were observed in patients treated with IM (Table): 19 patients with maculopapular rash with pruritus (no maculopapular rash without pruritus was detected), 7 patients with eczematous dermatitis such as stasis dermatitis and seborrheic dermatitis, 6 patients with onychodystrophy melanonychia (Figure 1), 5 patients with psoriasis, 5 patients with skin cancers including basal cell carcinoma (BCC)(Figure 2), 3 patients with periorbital edema (Figure 3), 3 patients with mycosis, 3 patients with dermatofibromas, 2 patients with dyshidrosis palmoplantar, 1 patient with pityriasis rosea–like eruption (Figure 4), and 1 patient with actinic keratoses on the face. No hypopigmentation or hyperpigmentation, excluding the individual case of melanonychia, was observed.
Figure 1. Melanonychia of the thumbs with slight onychodystrophy.
Figure 2. Basal cell carcinoma on dermoscopy showing large black-gray ovoid nests (original magnification ×40).
All cutaneous diseases reported in this study appeared after IM therapy (median, 3.8 months). The median time to onset for each cutaneous disorder is reported in the Table. During the first dermatologic visit before starting IM therapy, none of the patients showed any of these cutaneous diseases.
The adverse cutaneous reactions were treated with appropriate drugs. Generally, eczematous dermatitis was treated using topical steroids, emollients, and oral antihistamines. In patients with maculopapular rash with pruritus, oral corticosteroids (eg, betamethasone 3 mg daily or prednisolone 1 mg/kg) in association with antihistamine was necessary. Psoriasis was completely improved with topical betamethasone 0.5 mg and calcipotriol 50 µg. Skin cancers were treated with surgical excision with histologic examination. All treatments are outlined in the Table.
Imatinib mesylate therapy was suspended in 2 patients with maculopapular rash with moderate to severe pruritus; however, despite the temporary suspension of the drug and the appropriate therapies (corticosteroids and antihistamines), cutaneous side effects reappeared 7 to 10 days after therapy resumed. Therefore, the treatment was permanently suspended in these 2 cases and IM was replaced with erlotinib, a second-generation Bcr-Abl tyrosine kinase inhibitor.
Comment
The introduction of IM for the treatment of GIST and CML has changed the history of these diseases. The drug typically is well tolerated and few patients have reported severe AEs. Mild skin reactions are relatively frequent, ranging from 7% to 21% of patients treated.3 In our case, the percentage was relatively higher (25%), likely because of close monitoring of patients, with an increase in the incidence rate.
Imatinib mesylate cutaneous reactions are dose dependent.4 Indeed, in all our cases, the cutaneous reactions arose with an IM dosage of 400 mg daily, which is compatible with the definition of dose-independent cutaneous AEs.
