Neutrophilic panniculitis with vasculitis in a melanoma patient treated with vemurafenib: a case report and its management

[Panniculitis during BRAF inhibitor and/or MEK inhibitor therapy: A new case report and literature review]

INTRODUCTION

BRAF inhibitors±MEK inhibitors can cause panniculitis. Since the initial case described in 2012 by Zimmer et al., some sixty further cases have been reported. Based on a clinical study and a recent and complete review of the literature, we set out in detail the characteristics of panniculitis occurring during BRAF and MEK inhibition therapy as well as the treatment thereof.

PATIENTS AND METHODS

A 25-year-old-patient followed for multi-metastatic melanoma and taking dabrafenib and trametinib consulted for the appearance, twenty-two days after the start of targeted therapy (TT), of panniculitis of the legs and forearms possibly induced by the TT after other causes had been ruled out. The TT had been continued following dose reduction and corticoid therapy for ten days, and complete resolution occurred after fifteen days.

RESULTS

Fifty-three cases of panniculitis during BRAF±MEK inhibition therapy were analysed. The condition occurred mainly with BRAF inhibitors alone (especially vemurafenib), but it was also described with three combinations of BRAF and MEK inhibitors, regardless of age (median: 45 years), with a M/F ratio of 0.51, and in 50 % of cases, it occurred within the first month (time to onset: between 1 and 480 days). Non-specific biopsy is useful to rule out differential diagnoses. Symptomatic anti-inflammatory treatment, whether systemic or topical, may be given. In the absence of signs of severity, the TT may be continued.

CONCLUSION

When panniculitis occurs during BRAF±MEK inhibitor therapy, the causal role of the TT must be considered after full etiological investigation. It is essential to determine whether a causal relationship exists in order to avoid unwarranted cessation of treatment.

Tolerability of BRAF/MEK inhibitor combinations: adverse event evaluation and management

The inhibition of the mitogen-activated protein kinases signalling pathway through combined use of BRAF and MEK inhibitors (BRAFi+MEKi) represents an established therapeutic option in patients with BRAF-mutated, advanced melanoma. These efficient therapies are well tolerated with mostly moderate and reversible side effects and a discontinuation rate due to adverse events of 11.5%-15.7%. Median duration of therapy ranges between 8.8 and 11.7 months. Based on data from confirmatory trials, safety profiles of three BRAFi+MEKi combinations were reviewed, that is, dabrafenib plus trametinib, vemurafenib plus cobimetinib and encorafenib plus binimetinib. Many adverse events are class effects, such as cutaneous, gastrointestinal, ocular, cardiac and musculoskeletal events; some adverse events are substance associated. Fever (dabrafenib) and photosensitivity (vemurafenib) are the most common and clinically prominent examples. Other adverse events are less frequent and the association to one substance is less strong such as anaemia, facial paresis (encorafenib), neutropenia (dabrafenib), skin rash, QTc prolongation and increased liver function tests (vemurafenib). This narrative review provides recommendations for monitoring, adverse event evaluation and management focusing on the clinically relevant side effects of the three regimens.

Management of the cutaneous adverse effects of antimelanoma therapy

The advent of targeted therapy and immunotherapy has revolutionized the management of advanced melanoma. However, these novel therapies are associated with adverse effects (AEs), of which cutaneous toxicities are the most frequently observed. These cutaneous AEs can exert significant morbidity and impact on patient quality of life, hence the recognition and management of AEs is fundamental in preventing interruption or cessation of survival-prolonging treatments. Additionally, knowledge of these AEs are necessary in order for healthcare professionals to counsel patients when starting treatment and in the initiation of AE prophylaxis. The incidence and clinical presentation of the cutaneous toxicities of novel melanoma therapies will be discussed, and treatment guidelines provided.