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.

Inflamed actinic keratoses associated with pemetrexed and carboplatin therapy

Eruptive actinic keratosis (AK) consequent to systemic chemotherapy can be confused with drug allergies. We present the first case of inflamed AKs in one patient after receiving combination therapy with pemetrexed and carboplatin.A 68-year-old woman with non-small cell lung adenocarcinoma (NSCLC) presented with numerous pruritic ill-defined, gritty, erythematous papules consistent with AKs on her upper chest, upper back, and arms two weeks after completing the first cycle of combination therapy with carboplatin and pemetrexed. The care team managed her with topical steroids and the lesions resolved within one month. The patient resumed the second cycle of chemotherapy and reported the occurrence of a similar but milder eruption.This case illustrates that eruptive AKs should be considered in the differential diagnosis of drug-related rashes, especially if the physical exam is suggestive. The mainstay of treatment should be directed at symptomatic improvement, and chemotherapy may be continued.

Inflamed Actinic Keratoses After Pemetrexed

A 66-year-old man presented with a 1-day history of a mildly pruritic eruption on the face, chest, arms, and upper part of the back. The dermatitis began 3 weeks after receiving an initial infusion of pemetrexed (500 mg/m²) as induction chemotherapy for non-small cell lung cancer. Physical examination revealed numerous erythematous, scaly papules over the face, extensor surface of the arms, hands, and upper aspects of the chest and back, sparing sun-protected areas (Figure). He acknowledged that in the past he frequently went shirtless outdoors and rarely wore sunscreen or sun protective clothing during the many years he worked at construction sites. Results from a biopsy specimen from a typical lesion on the forearm revealed an inflamed actinic keratosis. Systemic chemotherapy was continued, and only emollients and mid-potency topical steroids were used to treat the skin eruption. At 2-week follow-up, the patient's eruption was greatly diminished with loss of significant erythema and scale, as well as absence of pruritus.

Skin lesions in patients treated with imatinib mesylate: a 5-year prospective study

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.

Mouse models for actinic keratosis and squamous cell carcinoma

This manuscript focuses on the use of mice to study the genetics and biology of cutaneous squamous cell carcinoma (SCC). Mice develop actinic keratosis-like lesions and SCC resembling those seen in humans. As an animal model, the mouse provides great experimental flexibility and has been useful in investigating aspects of the genetics and biology of SCC that are difficult to study in humans. We discuss the pros and cons of the various murine models available. How well mouse pathology in general mimics human disease remains an open question due to the vast differences in animal strain backgrounds and the fact that only one strain is typically tested in any particular experiment. Nonetheless, the murine epidermis is thinner than the human epidermis, and this must be kept in mind when making inferences from mechanistic data obtained with mice. We outline new strategies for non-biased screens to discover genes driving SCC progression. Such work has revealed a very complex interactive molecular network, and as with other complex diseases, the picture is being pieced together using systems biology strategies to which mouse tumour models are amenable. Such approaches do not focus on single genes or proteins but try to integrate the complex interactions of many types of genetic and biological information.

Cutaneous effects of BRAF inhibitor therapy: a case series

BACKGROUND

The cutaneous effects of rapidly accelerated fibrosarcoma kinase B (BRAF) inhibitors are not well understood. Squamous cell carcinoma (SCC), keratoacanthoma, and photosensitivity have been described in patients taking BRAF inhibitors.

PATIENTS AND METHODS

To characterize the timing and frequency of skin lesions in patients receiving BRAF inhibitor therapy, we utilized a retrospective case review of 53 patients undergoing treatment with BRAF inhibitors for 4-92 weeks of therapy. Patients were evaluated at baseline, and then followed at 4- to 12-week intervals. Charts were retrospectively reviewed, and the morphology and timing of cutaneous events were recorded.

RESULTS

Thirty-three of the 53 charts met exclusion/inclusion criteria, 15 were treated with vemurafenib, and 18 were treated with GSK 2118436/GSK 1120212. Of 33 patients treated with BRAF inhibitor, 13 developed photosensitivity (39.4%), 10 developed actinic keratoses (30.3%), 10 developed warts (30.3%), and 6 developed SCC (18.2%).

CONCLUSIONS

Multiple cutaneous findings were observed in the 33 patients taking BRAF inhibitors. The previously described association with SCC and photosensitivity was observed in these patients as well. Over half of the observed SCCs were invasive in nature. Photosensitivity continues to be frequent with BRAF inhibitors. Patients taking BRAF inhibitors should have regular full body skin exams. Further studies are necessary to better elucidate the rates of these adverse cutaneous effects.

Hydroxyurea-related toxicity in 3,411 patients with Ph'-negative MPN

Hydroxyurea (Hydroxycarbamide; HU) is commonly used for the long-term treatment of patients with Philadelphia-chromosome negative chronic myeloproliferative neoplasms (MPNs). It is considered a first-choice agent for the treatment of these disorders as underlined by the European Leukemia Net Consensus Conference [1], although it is formally approved for this indication in some countries only. The drug is reportedly well tolerated in the large majority of subjects, although systemic and/or localized toxicities have been reported. Consensus criteria for definition of "intolerance" to HU have been described;patients who develop intolerance are candidate for second-line therapy and, more recently, for investigational drugs. However, no epidemiologic information about the occurrence of the most clinically significant HU-associated adverse events is yet available. In this study, the authors report on a multicenter series of 3,411 patients who were treated with HU among which 184, accounting for 5% of total, developed significant drug-related toxicities. These data provide an estimate of the frequency and a detailed characterization of clinically significant HU-related toxicities; these information have relevance for the management of MPN patients who require second-line therapy after developing HU-related intolerance.