Successful dabrafenib transition after vemurafenib-induced toxic epidermal necrolysis in a patient with metastatic melanoma

[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.

Tolerability of BRAF and MEK Inhibitors for Metastasized Melanoma after Intra-Class Switch: A Multicenter, Retrospective Study

Targeted therapy with BRAF and MEK inhibitors (BRAFi, MEKi) is one of the mainstays of melanoma treatment. When dose-limiting toxicity (DLT) is observed, an option represents the intra-class switch to a different BRAFi+MEKi combination. Currently, there is scarce evidence for this procedure. This is a multicenter, retrospective analysis from six German skin cancer centers of patients who received two different combinations of BRAFi and MEKi. In total, 94 patients were included: 38 patients (40%) were re-exposed with a different combination because of previous unacceptable toxicity, 51 (54%) were re-exposed after progression, and 5 (5%) were included for other reasons. Of the 44 patients with a DLT during their first BRAFi+MEKi combination, only five (11%) experienced the same DLT during their second combination. A new DLT was experienced by 13 patients (30%). Six patients (14%) had to discontinue the second BRAFi treatment due to its toxicity. Compound-specific adverse events were avoided in the majority of patients by switching to a different combination. Efficacy data were similar to historical cohorts of BRAFi+MEKi rechallenge, with an overall response rate of 31% for patients who had previously progressed to treatment. We conclude that switching to a different BRAFi+MEKi combination if dose-limiting toxicity occurs is a feasible and rational approach in patients with metastatic melanoma.

Successful Dabrafenib Desensitization Protocols in a Patient with Metastatic Melanoma

Dabrafenib and trametinib are two available molecules that have been approved for the treatment of metastatic melanoma with BRAF-V600E or V600K mutations. Their combined therapy has led to long-lasting survival benefits and substantially improved outcomes. Until now, only a few cases of severe hypersensitivity reactions to dabrafenib and vemurafenib have been reported, and even fewer desensitization protocols to these molecules have been documented. We report the case of a 71-year-old female patient with metastatic melanoma harboring a BRAF-V600E mutation undergoing targeted therapy with dabrafenib and trametinib. Two weeks after the initiation of the combined treatment, she developed a hypersensitivity reaction. The cause–effect relationship between dabrafenib and the hypersensitivity reaction was demonstrated twice, when symptoms recurred upon dabrafenib reintroduction. We started a rapid 3-day dabrafenib desensitization protocol, which was well tolerated. When the patient discontinued the drug administration, we decided on a longer protocol that included more steps and more days in order to prevent the occurrence of other hypersensitivity reactions. Our patient tolerated both rapid and slow-going schedules, the first one reaching the final dose within 3 days and the second one reaching the total daily dose within 14 days. Depending on the patient’s needs, the severity of the hypersensitivity reaction and the hospital’s availability, the doctor may choose either the rapid or slow-going desensitization protocol.

Non-Apoptotic Cell Death Signaling Pathways in Melanoma

Resisting cell death is a hallmark of cancer. Disturbances in the execution of cell death programs promote carcinogenesis and survival of cancer cells under unfavorable conditions, including exposition to anti-cancer therapies. Specific modalities of regulated cell death (RCD) have been classified based on different criteria, including morphological features, biochemical alterations and immunological consequences. Although melanoma cells are broadly equipped with the anti-apoptotic machinery and recurrent genetic alterations in the components of the RAS/RAF/MEK/ERK signaling markedly contribute to the pro-survival phenotype of melanoma, the roles of autophagy-dependent cell death, necroptosis, ferroptosis, pyroptosis, and parthanatos have recently gained great interest. These signaling cascades are involved in melanoma cell response and resistance to the therapeutics used in the clinic, including inhibitors of BRAFmut and MEK1/2, and immunotherapy. In addition, the relationships between sensitivity to non-apoptotic cell death routes and specific cell phenotypes have been demonstrated, suggesting that plasticity of melanoma cells can be exploited to modulate response of these cells to different cell death stimuli. In this review, the current knowledge on the non-apoptotic cell death signaling pathways in melanoma cell biology and response to anti-cancer drugs has been discussed.