Early cutaneous lesions secondary to hydroxyurea therapy

Successful Management of Hydroxyurea-induced Leg Ulcers in Essential Thrombocythemia: Report of 3 Cases

Essential thrombocythemia is one of the myeloproliferative neoplasms with a plethora of thrombohemorrhagic complications. Hydroxyurea has been proven to be an effective treatment for this condition. However, it is not without side effects. We herein report 3 patients with essential thrombocythemia treated with hydroxyurea who developed refractory leg ulcers, and we outline their successful management. We also review the literature to shed light on the mechanism of this toxicity. Awareness of this important treatment complication is important to avoid the pitfall of futile invasive interventions.

Symptomatic mucocutaneous toxicity of hydroxyurea in Philadelphia chromosome-negative myeloproliferative neoplasms: the Mister Hyde face of a safe drug

BACKGROUND

The current study was conducted to evaluate severe mucocutaneous toxicity during treatment with hydroxyurea (HU) in a large cohort of patients with Philadelphia chromosome-negative myeloproliferative neoplasms (MPN).

METHODS

Among 993 consecutive patients newly diagnosed with MPN at 4 centers in Rome between January 1980 and December 2009, 614 patients (277 men and 337 women with a median age of 64.4 years [interquartile range (IR), 54.4 years-72.7 years]) received HU. HU was administered as first-line treatment in 523 patients (85.2%) and as ≥ second-line treatment in 91 patients (14.8%).

RESULTS

Mucocutaneous toxicity was reported in 51 patients (8.3%) after a median period from the initiation of HU treatment of 32.1 months (IR, 10.5 months-74.6 months) and a mean HU dose of 1085 mg (± 390 mg); 30 patients (58.8%) developed a painful ulcerative skin toxicity, mainly located in the perimalleolar area; 11 patients (21.6%) had oral aphthous ulcers; and 10 patients (19.6%) developed a nonulcerative skin toxicity with erythema and skin infiltration. After the mucocutaneous toxicity occurred, HU treatment was continued at the same dose in 5 patients (9.8%), reduced in 12 patients (23.5%), and temporarily discontinued in 7 patients (13.7%); the remaining 27 patients (52.9%) required a permanent drug discontinuation. After a median period of 4.3 months (IR, 2.4 months-9.0 months) from the onset of the skin toxicity, 39 patients (76.5%) had a complete resolution and 12 patients (23.5%) had improvement without complete resolution.

CONCLUSIONS

Mucocutaneous toxicity during HU treatment is more common than expected and may present with different clinical features. Moreover, it often requires a permanent drug discontinuation and only a partial resolution is reported to occur in approximately 25% of patients.

[Hydroxyurea--is it a harmless drug in Vaquez disease?]]

The frequent side effects of Hydroxy-Urea and the non-exceptional risk of leukemia and cancer in Polycythemia Vera treated for a long time by Hydroxy-Urea allow to conclude that Hydroxy-Urea is not an innocent drug. In a prospective trial of 150 patients with a median follow up of nine years, Hydroxy-Urea given alone induced side effects in 29% of patients necessitating to stop treatment in half of cases. The percentage of leukemia or myelodysplasia is 6.7% with an actuarial risk of leukemic transformation of 10% at 13 years. In an other prospective trial in 181 aged patients Hydroxy-Urea was given as maintenance therapy after 32P treatment. The median follow-up in that study is also of nine years. Side effects are observed in 13% of cases. A two fold increase of the leukemic risk was observed in the maintenance arm of the trial: 11 versus 19% at ten years, 14 vs 30% at 12 years, 16 vs 35% at 15 years because of the leukemogenic effect of Hydroxy-Urea in maintenance therapy we stopped including new patients in this arm of the trial.