Cutaneous adverse events to type I BRAF inhibitors: an analysis of effects associated with each inhibitor and therapeutic time interval to onset

[Drug-related exanthema under immunotherapy and targeted oncological therapy]

BACKGROUND

Oncological therapies can cause a variety of mucocutaneous adverse events. Exanthematous adverse events can be challenging in the context of the urgent need for cancer treatment due to their spread, sometimes rapid progression, and mucous membrane or organ involvement.

MATERIALS AND METHODS

This article provides an overview of the most important exanthematic dermatoses as side effects of modern drug-based tumor therapies with diagnostic and therapeutic information for clinicians, taking into account the current literature and guidelines.

RESULTS

Exanthematous adverse events of immune checkpoint inhibitors, EGFR antagonists, kinase inhibitors, bispecific T‑cell engagers, and the CCR4 inhibitor mogamulizumab are reviewed in detail.

CONCLUSIONS

Cutaneous side effects are common across all drug classes and cover a broad spectrum. While some adverse events are specific to one drug class, many exanthemas can occur with both oncological immunotherapies and various targeted therapies. A reliable diagnosis, dose adjustment or discontinuation of the offending agent in consultation with the treating oncologists and appropriate symptomatic therapy are important for correct management. In the case of severe, life-threatening drug reactions, however, permanent discontinuation of the drug is essential.

Cutaneous adverse reactions resulting from targeted cancer therapies: histopathologic and clinical findings

Targeted cancer treatments-designed to interfere with specific molecular signals responsible for tumor survival and progression-have shown benefit over conventional chemotherapies but may lead to diverse cutaneous adverse effects. This review highlights clinically significant dermatologic toxicities and their associated histopathologic findings, resulting from various targeted cancer drugs. Case reports and series, clinical trials, reviews, and meta-analyses are included for analysis and summarized herein. Cutaneous side effects resulting from targeted cancer therapies were reported with incidences as high as 90% for certain medications, and reactions are often predictable based on mechanism(s) of action of a given drug. Common and important reaction patterns included: acneiform eruptions, neutrophilic dermatoses, hand-foot skin reaction, secondary cutaneous malignancies, and alopecia. Clinical and histopathologic recognition of these toxicities remains impactful for patient care.

The risk of dermatological toxicities of combined BRAF and MEK inhibition versus BRAF inhibition alone in melanoma patients: a systematic review and meta-analysis

BACKGROUND

This meta-analysis was conducted to assess the risk of dermatological toxicities of combined BRAF and MEK inhibition versus BRAF inhibition alone in melanoma patients.

METHODS

We considered relevant prospective randomized phase I, II, and III trials of melanoma patients on the combined BRAF and MEK inhibition versus BRAF inhibition, describing events of rash, photosensitivity reaction (PR), hyperkeratosis (HK), alopecia, cutaneous squamous-cell carcinom(cSCC), skin papilloma(SP), pruritus, and hand-foot syndrome(HFS), as eligible for inclusion.

RESULTS

Eight trials comprising 3163 patients were included in the meta-analysis. The relative risks(RRs) of developing all-grade rash with combined BRAF and MEK inhibition versus BRAF inhibition was 1.59 (95%CI, 1.35-1.86, p < 0.00001), HK 0.33(95%CI, 0.16-0.66, p = 0.002), SP 0.09(95%CI, 0.04-0.24, p < 0.00001), alopecia 0.30(95%CI, 0.19-0.48, p < 0.00001), cSCC 0.23(95%CI, 0.17-0.31, p < 0.00001), HFS 0.18(95%CI, 0.13-0.26, p < 0.00001) and PR 0.40(95%CI, 0.26-0.61, p < 0.0001), while the RRs of high-grade dermatological toxicities from all included trials were: rash 0.54(95%CI, 0.20-1.43, p = 0.21), HK 0.18(95%CI, 0.06-0.53, p = 0.002), SP 0.14(95%CI, 0.02-1.16, p = 0.07), alopecia 0.72(95%CI, 0.14-3.62, p = 0.69), cSCC 0.23(95%CI, 0.17-0.33, p < 0.00001), HFS 0.40(95%CI, 0.08-2.06, p = 0.27), and PR 0.14(95%CI, 0.04-0.51, p = 0.003), respectly.

CONCLUSION

Our analysis of data has demonstrated that combined BRAF and MEK inhibitor-based treatment is associated with an increased risk of all-grade rash and a decreased risk of all-grade and high-grade HK, SP, alopecia, cSCC, HFS, and PR compared with single BRAF inhibitor alone in melanoma patients. Appropriate prevention and management are recommended.

The Role of Neutrophilic Inflammation, Angiotropism, and Pericytic Mimicry in Melanoma Progression and Metastasis

Angiotropism in melanoma correlates with ulceration and poor prognosis. It has been shown to be a marker of pericytic mimicry, that is, the spreading of tumor cells in a pericyte location along abluminal vascular surfaces. Such extravascular tumor spread may represent another form of tumor plasticity with reversion to a neural crest cell migratory phenotype. In a murine melanoma model, it has recently been demonstrated that neutrophilic skin inflammation promotes angiotropism and metastatic spread of primary melanomas. This review discusses the role of neutrophilic inflammation in angiotropism and pericytic mimicry in melanoma progression, metastasis, tumor cell plasticity, and tumor therapeutic resistance.

Late-onset robust curly hair growth in a patient with BRAF-mutated metastatic melanoma responding to dabrafenib

Development of curly hair has been infrequently described in association with BRAF inhibitors in clinical trials, and usually affects patients between 6 and 24 weeks of therapy. The curly hair is typically preceded by initial hair thinning or even diffuse alopecia. We report herein an occurrence of late-onset robust curly head hair growth in a patient with metastatic melanoma responding well to dabrafenib, without being preceded by hair thinning. The curly hair in our patient developed at 11 months of therapy with dabrafenib. Occurrence of late-onset, robust curly hair might represent a prognostic marker of clinical response to these agents. If our hypothesis is correct, we expect more reports of late-onset, robust curly hair growth with the use of this class of pharmaceuticals. Moreover, newer generations of BRAF inhibitors may expand the armory of hair care products in the future.

Risk factors for keratinocyte skin cancer in patients diagnosed with melanoma, a large retrospective study

BACKGROUND

Melanoma survivors are at an increased risk of developing other malignancies, including keratinocyte skin cancer (KSC). While it is known that many risk factors for melanoma also impact risk of KSC in the general population, no previous study has investigated risk factors for KSC development in melanoma patients.

OBJECTIVE

We assessed associations of personal and clinical characteristics, including skin phenotype and variations in the melanocortin 1 receptor (MC1R) gene, with KSC risk in melanoma patients.

PATIENTS AND METHODS

We used prospective follow-up information on 1200 patients treated for melanoma at the Instituto Valenciano de Oncología, Spain, between 2000 and 2011. We computed hazard ratios and 95% confidence intervals (CIs) for the association of clinical, personal and genetic characteristics with risk of KSC, squamous cell carcinoma (SCC), or basal cell carcinoma (BCC) from Cox proportional hazard models. Five-year cumulative incidence based on competing risk models of SCC, BCC or KSC overall was computed using multivariate subdistribution hazard models. To assess predictive performance of the models, we computed areas under the receiver-operating characteristic curves (AUCs, discriminatory power) using cross-validation.

RESULTS

Median follow-up was 57.2 months; a KSC was detected in 163 patients (13.6%). In multivariable Cox models, age, sex, sunburns, chronic sun exposure, past personal history of non-melanoma skin cancer or other non-cutaneous neoplasia, and the MC1R variants p.D294H and p.R163Q were significantly associated with KSC risk. A cumulative incidence model including age, sex, personal history of KSC, and of other non-cutaneous neoplasia had an AUC of 0.76 (95% CI: 0.71-0.80). When p.D294H and p.R163Q variants were added to the model, the AUC increased to 0.81 (95% CI: 0.77-0.84) (p-value for difference <0.0001).

CONCLUSIONS

In addition to age, sex, skin characteristics, and sun exposure, p.R163Q and p.D294H MC1R variants significantly increased KSC risk among melanoma patients. Our findings may help identify patients who could benefit most from preventive measures.