[Secondary cutaneous effects of hydroxyurea: prospective study of 26 patients from a dermatologic consultation]

Controversies in the pathophysiology of leg ulcers in sickle cell disease

Patients with sickle cell disease (SCD) often experience painful vaso-occlusive crises and chronic haemolytic anaemia, as well as various acute and chronic complications, such as leg ulcers. Leg ulcers are characterized by their unpredictability, debilitating pain and prolonged healing process. The pathophysiology of SCD leg ulcers is not well defined. Known risk factors include male gender, poor social conditions, malnutrition and a lack of compression therapy when oedema occurs. Leg ulcers typically start with spontaneous pain, followed by induration, hyperpigmentation, blister formation and destruction of the epidermis. SCD is characterized by chronic haemolysis, increased oxidative stress and decreased nitric oxide bioavailability, which promote ischaemia and inflammation and consequently impair vascular function in the skin. This cutaneous vasculopathy, coupled with venostasis around the ankle, creates an ideal environment for local vaso-occlusive crises, which can result in the development of leg ulcers that resemble arterial ulcers. Following the development of the ulcer, healing is hindered as a result of factors commonly observed in venous ulceration, including venous insufficiency, oedema and impaired angiogenesis. All of these factors are modulated by genetic factors. However, our current understanding of these genetic factors remains limited and does not yet enable us to accurately predict ulceration susceptibility.

Hiperpigmentação Mucocutânea Associada à Terapia de Hidroxiureia em Paciente com Trombocitemia Essencial: Relato de Caso

Introdução: A hiperpigmentação mucocutânea é uma condição dermatológica que pode estar relacionada a tratamentos quimioterápicos, a exemplo das terapias com uso de hidroxiureia (HU). A HU é um fármaco citostático de amplo uso nas doenças mieloproliferativas e compõe a principal linha de tratamento da trombocitemia essencial (TE). O presente estudo tem por objetivo relatar um caso raro de hiperpigmentação mucocutânea em um paciente com TE. Relato do caso: Paciente do sexo masculino, 68 anos de idade, 89 kg, com diagnóstico de TE, em uso de HU 2 g/dia. Com três meses de terapia, apresentou lesões hiperpigmentadas de coloração acastanhadas em pele das mãos e mucosa oral (língua). Em decisão partilhada com o médico-assistente, o paciente optou pela continuação do uso do medicamento. Após seis anos de acompanhamento, as lesões mantêm-se estáveis. Conclusão: A hiperpigmentação mucocutânea associada à terapia com HU é um evento benigno secundário ao uso do fármaco e não exige a interrupção de uso, porém, sua retirada, ou redução das doses, geralmente leva à diminuição ou ao desaparecimento das lesões.

Hydroxyurea: a reappraisal of its cutaneous side effects and their management

Hydroxyurea (HU) is known to cause a broad spectrum of cutaneous side effects, ranging from relatively benign to severe. Although dermatologists are often consulted for the treatment of these side effects, a comprehensive resource discussing the different types and their management is lacking. In this study, we conducted a literature search in order to critically evaluate the reported types and management of hydroxyurea's cutaneous side effects, as well as review its mechanism of action, dermatologic uses, and common systemic side effects. Relatively common and benign side effects include hyperpigmentation, xerosis, and skin atrophy. While serious cutaneous side effects such as leg ulcers or nonmelanoma skin cancers occur in a substantial proportion of patients, these may resolve with HU discontinuation and proper dermatologic management. Therefore, it is crucial for dermatologists to be aware of these various cutaneous side effects and their management as prompt diagnosis and proper treatment will improve patient outcomes.

Drug-Related Cutaneous Adverse Events in Philadelphia Chromosome-Negative Myeloproliferative Neoplasms: A Literature Review

Since myeloproliferative neoplasms (MPN) pose a significant risk for vascular and thrombotic complications, cytoreductive therapies, such as hydroxyurea (HU), interferon (IFN) inhibitors, and Janus kinase (JAK) inhibitors are recommended for patients at high risk. However, these agents also place patients at increased risk for drug-related cutaneous adverse events. Herein, we review the literature on skin toxicity related to the use of drugs for the treatment of MPN. Overall, the cytoreductive agents used for MPN are generally well tolerated and considered to be safe, except IFN, for which dropout rates as high as 25% have been reported. While IFN is known to give rise to flu syndrome, it rarely leads to hematological alterations. The most common hematological side effects of HU are mild and include granulocytopenia, anemia, and thrombocytopenia. The JAK inhibitor ruxolitinib has been associated with cytopenia and a higher incidence of viral infections, as well as increased risk for basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Based on the present analysis, it can be concluded that cutaneous toxicity is not a negligible complication of commonly used treatments for MPN. While further research is needed, patients on these agents, and especially those with a history of cutaneous malignancies, should undergo thorough skin examination before and during therapy. In addition, detailed history is critical since many patients who develop non-melanoma skin cancer have multiple preexisting risk factors for cutaneous carcinogenesis.

Sickle cell disease induces resistance to cutaneous carcinogenesis

Background

While skin carcinomas are reported in chronic ulcers and in patients treated with hydroxyurea (HU) for myeloproliferative neoplasms, no skin carcinoma has been reported in patients with sickle cell disease (SCD), presenting chronic skin ulcers or treated with HU. The objective was to estimate the risk of cutaneous malignant transformation in SCD patients with prolonged leg ulcers or under HU therapy.

Results

In this cross-sectional study, the cohort consisted of 1543 patients. In the first series, 29 patients presented a total of 53 ulcers lasting more than two years. The median age was 35 ± 8.4 years old. The median duration for a single ulcer was 9.2 ± 7 years. None of the examined ulcers showed any suspicious area of malignant transformation. In the second series, 187 patients treated with HU for more than two years were identified. The median age was 31.3 ± 9.9 years old. The median duration of treatment with HU was 6 ± 3.2 years. No skin carcinoma or actinic keratosis was recorded.

Conclusions

This study showed that skin carcinogenesis did not occur in our series of SCD patients exposed to transforming events such as long term HU treatment or prolonged leg ulcers.

Nonmelanoma skin cancer associated with Hydroxyurea treatment: Overview of the literature and our own experience

Nonmelanoma skin cancer is the most common malignant tumor in the fair skin population, with each year several millions of diagnosed cases. Their most common risk factors are fair skin, a history of excessive ultraviolet light exposure, chronic inflammatory skin conditions, exposure to radiation, and contact with arsenic. Certain drugs can also be associated with a higher risk of nonmelanoma skin cancer. These include hydroxyurea, which acts as a metabolic inhibitor of ribonucleotide reductase and a potent nonalkylating myelosuppressive agent. It is used for the treatment of various myeloproliferative disorders, including chronic myeloid leukemia, polycythemia vera, and essential thrombocytopenia. Several publications describe an increased occurrence of skin manifestations following hydroxyurea treatment. A growing body of evidence indicates a possible role of hydroxyurea in skin cancer progression. In this review article, we summarize some relevant observations about the association of hydroxyurea and skin cancer, and we describe our own clinical experiences to provide up to date recommendations about the care of patients on hydroxyurea therapy.

Leg ulcer induced by hydroxycarbamide in sickle cell disease: What is the therapeutic impact?

Major sickle cell disease syndrome (SCD) is a set of potentially serious and disabling constitutional haemoglobin pathologies characterised by chronic haemolysis and vaso-occlusion phenomena. If expression takes the form of acute vaso-occlusive crisis, SCD is currently considered to be a chronic systemic pathology, primarily associated with vasculopathy and ischaemia-reperfusion phenomena. The haemolytic aspect of the disease may be associated with endothelial dysfunctional complications, including leg ulcers, which are a classic spontaneous complication of major SCD. Their frequency, all aetiologies combined, varies considerably according to the series under consideration. Hydroxycarbamide has become the standard treatment for some SCD phenotypes, but has classically been described as one of the causes of leg ulcer. This causality is widely debated and is still difficult to establish because it is a specific complication of the disease. Comorbidity factors (eg, iron deficiency) are also often implicated as causal or aggravating factors so research into all the potential aetiologies of leg ulcers in a sickle cell patient must be exhaustive. We discuss the aetiologies of a leg ulcer in a patient treated by hydrocarbamide for major SCD. The imputation of the drug was established, followed by a marrow allograft in this patient.

Essential Thrombocythemia: The Dermatologic Point of View

Essential thrombocythemia (ET) is a myeloproliferative neoplasm characterized by an increase in blood platelets and dominated by a predisposition to vascular events. Cutaneous manifestations can complicate its course. itching has been the most common symptom reported; however, the percentage has ranged from 3% to 46%, depending on the survey. Erythromelalgia is found in 6% of cases, and livedo reticularis, minor bleeding, acrocyanosis, and Raynaud's phenomenon are rare manifestations. It is important to recognize and treat these events, because they can affect patients' quality of life and could worsen the prognosis. In addition to skin involvement as a possible sign of ET, the treatment of ET can be associated with cutaneous complications. Hydroxycarbamide, interferon-alfa, and anagrelide can induce different skin lesions. Hydroxycarbamide has been associated with major complications, including painful leg ulcers and actinic keratoses. Minor events include alopecia and hyperpigmentation. Xerosis, pruritus, and photosensitivity are some of the complications reported by patients treated with interferon-alfa. Anagrelide has proved to be associated with fewer dermatologic effects, only detected in single cases. Knowledge of the ET cutaneous manifestations, together with the clinical examination findings, can result in an earlier diagnosis and the start of effective treatment.

Successful treatment of hydroxyurea-associated chronic leg ulcers associated with squamous cell carcinoma

Hydroxyurea (HU) is an antineoplastic drug used in the treatment of chronic myeloproliferative neoplasms (MPNs). HU is associated with cutaneous adverse effects, whereas severe complications such as leg ulcers and non-melanoma skin cancers (NMSCs) are rare and only observed after long-term treatment. We herein report a patient with essential thrombocythemia (ET) treated chronically with HU, and who developed refractory bilateral leg ulcers complicated by squamous cell carcinoma (SCC) over both heels. The patient was successfully managed by multiple debridement stages and skin grafting surgeries.

Mucocutaneous side effects of antineoplastic chemotherapy

All structures of the skin may be affected by side effects of antineoplastic chemotherapy. The most commonly described effects concern skin adnexes, especially hair with alopecia. Nails are also frequently involved. Eccrine sweat or sebaceous gland involvement is more rarely reported. Mucous membranes, particularly in the mouth, are frequently altered by several mechanisms; direct cytotoxicity, infection, and a decrease in polymorphonuclear or platelet counts. Among cutaneous side effects, hyperpigmentation is very common and may have different clinical patterns; generalised, figurated, or localised. Acral erythema is another cutaneous side effect that is relatively specific to chemotherapy and is often dose-related. Some cutaneous side effects are related to an interaction between chemotherapy and radiation, particularly phototoxicity, recall phenomenon, and radiation enhancement. Miscellaneous, less frequent, side effects are described; sclerodermiform dermatitis, Raynaud's phenomenon, and hypersensitivity syndrome. In some cases, cutaneous side effects are relatively specific to one type of drug. Capillary leak syndrome is most often related to taxanes. Hydroxyurea is responsible for some peculiar cutaneous side effects (ulcerations, pseudo-dermatomyositis), perhaps due to long-term administration of the drug. Although mucocutaneous side effects of chemotherapy are frequent and sometimes severe, interruption of the culprit drug is rarely mandatory. However, adaptation of the dosage or prevention of some of these side effects remains necessary. Antineoplastic chemotherapies are widely used in many therapeutic protocols and may be responsible for numerous mucocutaneous side effects, either specific or more unusual. In rare cases, the severity of these side effects may require interruption of therapy. They may involve skin adnexes, mucous membranes or the skin itself. This review discusses cytotoxic antineoplastic drugs only, not cytokines, monoclonal antibodies or transduction factors used in the treatment of cancer.

Hydroxyurea-associated squamous dysplasia

We report 2 cases of squamous dysplasia associated with long-term hydroxyurea therapy. The association between hydroxyurea and multiple aggressive squamous cell carcinomas, Bowen's disease, and multiple actinic keratoses in sun-exposed areas after a variable latency period has been increasingly reported. On reviewing the literature, 17 cases were identified and are reviewed, with emphasis on possible pathogenetic mechanisms of carcinogenicity. Squamous dysplasia, a precursor state to a more aggressive condition of multiple squamous cell carcinomas in photoexposed areas, should be added to the well-known cutaneous toxicities of hydroxyurea therapy.

Longitudinale Melanonychie bei Einnahme von Hydroxycarbamid. Longitudinal melanonychia induced by hydroxyurea therapy

Four case reports of patients with myeloproliferative syndrome receiving therapy with hydroxycarbamide (synonymous: hydroxyurea) and developing streaky longitudinal pigmentation appeared in fingernails and toenails several months after starting this therapy.

BACKGROUND

Pigmentation of finger- and toenails presents a wide range of differential diagnostic considerations. They can be of infectious, melanocytic or exogenous origin or caused by metabolic disorders.

PATIENTS AND METHODS

Three women and one man, ranging in age from 62 and 87 years, were treated with hydroxycarbamide for myeloproliferative syndrome or chronic myelogenous leukemia for five to twelve years. All four patients were Fitzpatrick skin types II.

RESULTS

Several months after starting this therapy, they developed streaky longitudinal pigmentation of their fingernails and toenails. In two patients, these findings were diagnosed by chance, whereas two patients sought dermatological advice because of nail pigmentation. In two of the patients the longitudinal pigmentation disappeared a few month after discontinuation of hydroxycarbamide. The melanonychia persisted in another patient, while the fourth was lost to follow-up.

CONCLUSIONS

When melanonychia is identified in hematology-oncology patients, a careful medical history should be obtained. A list of medications is crucial, since hydroxycarbamide causes nail pigmentation. In each case of nail pigmentation, an acral lentiginous melanoma must be excluded.

Mucocutaneous adverse effects of hydroxyurea: a prospective study of 30 psoriasis patients

Hydroxyurea is an anti-tumour agent most commonly used to treat chronic myeloproliferative disorders in doses up to 4 g per day. Dermatological adverse effects reported so far have been observed predominantly in these patients. As we are treating selected psoriasis patients with low dose hydroxyurea we attempted to define the spectrum and chronology of dermatological adverse effects in this group of patients prospectively. Of the 29 evaluable patients, 19 (65.5%) developed a mucocutaneous adverse reaction after a mean duration of 6.4 weeks of treatment. Pigmentation of nails, skin or mucosa was the most common observation and was seen in 17 (58.6%) patients. Other less common findings were xerosis, diffuse alopecia, oedema of the legs, oral ulcers and actinic psoriasis. Adverse effects subsided in 11 (57.9%) patients during a mean follow up of 18 weeks. Three hitherto unreported side-effects - scleral pigmentation, acquired ichthyosis and pigmentation of lunula of the nails - were noted. This first study of dermatological adverse effects of hydroxyurea therapy on Asian psoriatic patients reveals several new findings. Pigmentation of skin, nails and mucosa appears to be very common and occurs early. Serious dermatological side-effects probably do not occur with low dose (up to 1.5 g per day) hydroxyurea in patients with psoriasis.

Rediscovering hydroxyurea: its role in recalcitrant psoriasis

BACKGROUND

There is an acute paucity of second-line systemic agents for the treatment of extensive chronic plaque psoriasis (CPP). Recent studies using hydroxyurea in patients with HIV infection and sickle cell anemia have rekindled interest in this old drug and have provided more data regarding safety and dosage.

OBJECTIVE

We wanted to test the efficacy and tolerability of hydroxyurea in patients with extensive CPP who had to discontinue first-line oral agents for any reason.

METHODS

The study was a prospective nonrandomized series. Thirty-one patients, including 26 with prior history of systemic antipsoriatic therapy were given hydroxyurea 1-1.5 g per day for a median duration of 36 weeks. They were followed up for a mean period of 36.1 +/- 13.8 weeks.

RESULTS

Almost 75% of the patients showed an adequate response (35% reduction in Psoriasis Area and Severity Index at or before 8 weeks) with over half showing more than 70% reduction in PASI score. All adverse effects were mild and reversible and none of the patients required cessation of therapy.

CONCLUSION

Hydroxyurea is an effective, very safe but relatively slower acting alternative for patients with extensive CPP over the short-to-medium term.