Melanoma patients under vemurafenib: prospective follow-up of melanocytic lesions by digital dermoscopy

Utilization of Imaging Modalities in the Diagnosis of Melanoma: A Scoping Review

Melanomas arise de novo or in the context of a precursor lesion. Lesions typically grow radially and then undergo a vertical growth phase proceeding to local invasion and metastasis. This review describes the utility of different imaging modalities in diagnosis and melanocytic lesion monitoring. A literature search was performed in November 2023 utilizing EMBASE, Medline, and PubMed. The PRISMA diagram demonstrates the review process. Reflectance confocal microscopy (RCM) utilizes near-infrared light to help diagnose dermatologic lesions. RCM was found to demonstrate nearly two times the positive predictive value compared to dermoscopy. The introduction of the Berlin Ultrasound (US) Morphology Criteria permitted a 65-80% improvement in diagnostic sensitivity. US with fine-needle aspiration cytology (FNAC) accurately predicts the necessity for sentinel lymph node biopsy and lymphadenectomy, sparing patients with metastasis and prompting biopsy for equivocal lesions. Single-photon emission computed tomography/computed tomography (SPECT/CT) is an adjunctive tool to anatomically and functionally assess lymphatic invasion. SPECT/CT improves the detection of sentinel nodes while decreasing operating time and improving cosmetic outcomes. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) with small voxel reconstruction demonstrated increased specificity and sensitivity for detecting in-transit metastases of melanomas, specifically in the limbs. Dermoscopy allows providers to cost-effectively recognize common lesion patterns. Multiphoton microscopy assigns a weight-based score based on malignant features. Optical coherence angiography captures images of vessels to help diagnose equivocal lesions. Utilization of imaging techniques may increase diagnostic accuracy, reduce unnecessary procedures, and help guide treatment plans. Additional research is needed to further characterize the utility of these techniques in order to improve the diagnosis and treatment of melanomas.

Ponatinib-induced eruptive nevi and melanocytic proliferation

Ponatinib, an oral third-generation tyrosine kinase inhibitor, is indicated for the treatment of imatinib-resistant leukemia. We experienced a case of ponatinib-induced eruptive nevi, and the biologic effects of ponatinib on melanocytes were investigated. Treatment with ponatinib significantly increased the proliferation of normal human melanocyte or melanoma cells through the upregulation of the extracellular signal-regulated kinase and protein kinase B signaling pathways. The downstream molecules of cyclin B1 and D1 were significantly increased in ponatinib-treated melanocytes. These results demonstrate the capacity of ponatinib to induce the proliferation and tumorigenesis of melanocytes.

Cutaneous toxicities from targeted therapies used in oncology: Literature review of clinical presentation and management

•

Cutaneous toxicities are frequent with targeted therapies.

•

Managing cutaneous toxicities is critical for life-saving treatment continuation.

•

Dermatologists can provide a key input in preventing and managing these toxicities.

With the development of molecular targeted therapies, a wide array of dermatologic toxicities is appearing. Their prevention, recognition, and management by dermatologists is critical to ensure antineoplastic treatment continuation. The objective of this study was to provide a literature review of the most common dermatologic toxicities due to targeted therapies in oncologic patients, including their clinical presentation, prevention, and management.

Cutaneous adverse events in children treated with vemurafenib for refractory BRAFV600E mutated Langerhans cell histiocytosis

BACKGROUND

The somatic BRAF^V600E mutation occurs in 38-64% of pediatric cases of Langerhans cell histiocytosis (LCH). Vemurafenib (VMF), a BRAF inhibitor, was approved for refractory BRAF^V600E mutated LCH. In adults, VMF causes frequent cutaneous adverse events (CAE) including skin tumors (squamous cell carcinomas, melanomas), but little is known in children. The objective of this study was to evaluate the frequency, clinical spectrum, and severity of CAEs in children treated with VMF for LCH. In addition, a correlation between CAE occurrence and VMF dose, residual plasma levels (RPLs), and efficacy was searched for.

PROCEDURE

Multicentric retrospective observational study including patients <18 years treated with VMF alone for refractory BRAF^V600E mutated LCH in 13 countries between October 1, 2013 and December 31, 2018.

RESULTS

Fifty-seven patients: 56% female, median age 2.1 years (0.2-14.6), median treatment duration 4.1 months (1.4-29.7). Forty-one patients (72%) had at least one CAE: photosensitivity (40%), keratosis pilaris (32%), rash (26%), xerosis (21%), and neutrophilic panniculitis (16%). No skin tumor was observed. Five percent of CAEs were grade 3. None were grade 4 or led to permanent VMF discontinuation. Dose reduction was necessary for 12% of patients, temporary treatment discontinuation for 16%, none leading to loss of efficacy. VMF dose, median RPL, and efficacy were not correlated with CAE occurrence.

CONCLUSIONS

At doses used for pediatric LCH, CAEs are frequent but rarely severe and have little impact on the continuation of treatment when managed appropriately. Regular dermatological follow-up is essential to manage CAEs and screen for possible induced skin tumors.

[Management of toxicities of BRAF inhibitors and MEK inhibitors in advanced melanoma]

Major therapeutic advances have been made recently in the treatment of metastatic melanoma, due to the development of targeted therapies, namely BRAF and MEK inhibitors, in patients with BRAF V600 mutation. Combinations of vemurafenib+cobimetinib, dabrafenib+trametinib, et encorafenib+binimetinib, evaluated in coBRIM, COMBI-d/COMBI-v and COLUMBUS trials respectively have been approved in this indication. Toxicities induced by combination therapies are different from those reported with monotherapies, in terms of frequency and intensity. Physicians who treat melanoma patients thus face news issues relating to prevention, detection and treatment of these adverse events. This paper summarizes tolerance data from the three pivotal trials (coBRIM, COMBI-v and COLUMBUS) and issues recommendations for the specific management of main toxicities, based on experts' opinion. We discuss dermatological, ophthalmological, cardiovascular, digestive, musculoskeletal, renal and general toxicities and propose a timetable for examinations to be performed before and during treatment.

Dermatological side effects of immunotherapy drugs and targeted cancer therapies: Importance of dermatology and oncology collaboration

INTRODUCTION

Novel anti-cancer drugs such as targeted cancer therapies and immune check-point inhibitors (ICIs) have adverse events, especially concerning the skin. The aim of this study is to report an overview of the commonly consulted dermatological side effects of ICIs and targeted cancer therapies in clinical practice, along with their management.

METHODS

In this single-center study, we evaluated consecutive oncological patients who were referred from the oncology outpatient clinic to the dermatology outpatient clinic due to skin side effects of ICIs and targeted therapies. All patients were examined and treated at the same day of referral by experienced dermatologists. Patient characteristics, clinical findings, diagnostic workups and treatments were retrieved from outpatient records.

RESULTS

Sixty three patients were enrolled. Most common diagnoses were lung carcinoma, melanoma and colon carcinoma. Fifty patients (79%) were using targeted therapies while 13 (21%) were using ICIs. Xerosis was the most common side effect (44%), followed by acneiform rash, paronychia, eczema and pruritus. Majority of the side effects were grade 2 and 3. Psoriasis was a common side effect of ICIs. One patient had a newly developed dysplastic nevus on vemurafenib treatment. Oncological treatment was not withheld in any of the patients.

CONCLUSIONS

This study revealed the most commonly consulted skin side effects of novel anti-cancer drugs and their management in daily practice. We underlie the importance of collaborative work of oncology and dermatology professionals as early management of cutaneous side effects of targeted therapies and ICIs improves patient outcomes.

Long-term vemurafenib therapy in advanced melanoma patients: cutaneous toxicity and prognostic implications

BACKGROUND

The introduction of targeted therapies for the treatment of BRAF-mutated metastatic melanoma was associated with different cutaneous adverse events (AEs).

OBJECTIVES

To describe the type, frequency and severity of cutaneous AEs related to vemurafenib; to understand the association between AEs and vemurafenib efficacy in terms of median overall survival (OS) and median progression-free survival (PFS); to identify molecular characteristics of long-term responders.

METHODS

This observational, retrospective, monocentric study included all consecutive patients with unresectable stage III or stage IV melanoma and BRAF V600E mutation that started treatment with vemurafenib between May 2012 and May 2014.

RESULTS

62 patients with a median age of 56 years (range 26-82) were enrolled and received vemurafenib for a median period of 7.9 months (range 0.8-63.7). Among them, 45 patients presented at least one skin AE, 12 reduced the dosage due to cutaneous toxicity, and only one firstly reduced and after stopped the therapy. No specific molecular biomarkers were detected in long-term survivors.

CONCLUSIONS

Among long-term survivors, skin AEs seem to be less frequent and less severe. Results on multivariable analysis revealed that the presence of at least one G2 toxicity is a protective factor considering PFS, but not in terms of OS.

Management of dermatologic adverse events from cancer therapies: recommendations of an expert panel

With the development of new cancer therapies, systemic toxicity profile and effects on survival achieved an important improvement. However, a constellation of toxicities has emerged, even more remarkably, cutaneous adverse events. This report, developed by a board of Brazilian experts in oncodermatology, aims to establish a guideline for the dermatological care of oncologic patients. When possible, evidence-based recommendations were made, but in many cases, when strong evidence was not available, a consensus was reached, based on some data supporting therapies combined with personal experiences.

Personalized and targeted mutational analysis of multiple second primary melanomas under kinase inhibitors

BACKGROUND

Second primary melanomas (SPMs) are new developed primary melanomas occurring in a subset of patients affected by BRAF-mutated metastatic melanoma during treatment with BRAF-inhibitors. A drug-induced paradoxical activation of mitogen-activated protein kinase (MAPK) signaling pathway in BRAF-wild type/RAS-mutated cells have been proposed as a possible molecular mechanism but data on the mutational status of SPMs are lacking. In order to better understand genetic alterations affecting the biological mechanism of SPMs, we performed a personalized and targeted next-generation sequencing analysis of a patient affected by metastatic melanoma who developed multiple SPMs during treatment with encorafenib (LGX818).

METHODS

Using a cancer panel of 50 genes for solid tumors enriched with a custom panel of 10 genes specifically involved in melanoma pathogenesis, we analyzed the primary melanoma, two SPMs, one benign compound nevus and the normal DNA extracted from blood lymphocytes of the patient.

RESULTS

We identified HRAS Q61 somatic mutation in one SPM developed in a pre-existing nevus. In the primary melanoma, besides the BRAF mutation, we identified the clinically actionable IDH1 R132C somatic mutation. Both SPMs were BRAF wild type. The patient harbors the recently recognized pathogenetic germline variant KDR Q472. We observed that mutations detected in tumor samples involving genes related to melanoma pathogenesis (TP53, PIK3CA, FGFR3, ATF1, KIT, HRAS and MAP2K2) were present in heterozygosis in the germline status of the patient.

CONCLUSIONS

Our results support the paradoxical mechanism of MAPK pathway for SPMs under BRAF inhibitors. Moreover, they suggest that targeted mutational assessment based on matching somatic and germline analysis represent a promising approach to detect the neoplastic landscape of the tumor and to identify most accurate treatment in metastatic melanoma patient.

Malignant Melanoma: Diagnostic and Management Update

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Summarize the changes to the American Joint Committee on Cancer Eighth Edition Melanoma Staging System. 2. List advances in genetic, molecular, and histopathologic melanoma diagnosis and prognostication. 3. Recommend sentinel lymph node biopsy and appropriate surgical margins based on individualized patient needs. 4. Recognize the currently available treatments for in-transit metastasis and advanced melanoma. 5. Describe current and future therapies for melanoma with distant visceral or brain metastases.

SUMMARY

Strides in melanoma surveillance, detection, and treatment continue to be made. The American Joint Committee on Cancer Eighth Edition Cancer Staging System has improved risk stratification of patients, introduced new staging categories, and resulted in stage migration of patients with improved outcomes. This review summarizes melanoma advances of the recent years with an emphasis on the surgical advances, including techniques and utility of sentinel node biopsy, controversies in melanoma margin selection, and the survival impact of time-to-treatment metrics. Once a disease manageable only with surgery, a therapeutic paradigm shift has given a more promising outlook to melanoma patients at any stage. Indeed, a myriad of novel, survival-improving immunotherapies have been introduced for metastatic melanoma and more recently in the high-risk adjuvant setting.

Toxic Side Effects of Targeted Therapies and Immunotherapies Affecting the Skin, Oral Mucosa, Hair, and Nails

Targeted therapies and immunotherapies are associated with a wide range of dermatologic adverse events (dAEs) resulting from common signaling pathways involved in malignant behavior and normal homeostatic functions of the epidermis and dermis. Dermatologic toxicities include damage to the skin, oral mucosa, hair, and nails. Acneiform rash is the most common dAE, observed in 25–85% of patients treated by epidermal growth factor receptor and mitogen-activated protein kinase kinase inhibitors. BRAF inhibitors mostly induce secondary skin tumors, squamous cell carcinoma and keratoacanthomas, changes in pre-existing pigmented lesions, as well as hand-foot skin reactions and maculopapular hypersensitivity-like rash. Immune checkpoint inhibitors (ICIs) most frequently induce nonspecific maculopapular rash, but also eczema-like or psoriatic lesions, lichenoid dermatitis, xerosis, and pruritus. Of the oral mucosal toxicities observed with targeted therapies, oral mucositis is the most frequent with mammalian target of rapamycin (mTOR) inhibitors, followed by stomatitis associated to multikinase angiogenesis and HER inhibitors, geographic tongue, oral hyperkeratotic lesions, lichenoid reactions, and hyperpigmentation. ICIs typically induce oral lichenoid reactions and xerostomia. Targeted therapies and endocrine therapy also commonly induce alopecia, although this is still underreported with the latter. Finally, targeted therapies may damage nail folds, with paronychia and periungual pyogenic granuloma distinct from chemotherapy-induced lesions. Mild onycholysis, brittle nails, and a slower nail growth rate may also be observed. Targeted therapies and immunotherapies often profoundly diminish patients’ quality of life, which impacts treatment outcomes. Close collaboration between dermatologists and oncologists is therefore essential.

Cutaneous toxicities of new treatments for melanoma

New drugs against advanced melanoma have emerged during last decade. Target therapy and immunotherapy have changed the management of patients with metastatic disease. Along with its generalized use, drug toxicities have appeared and the skin is the target organ of a significant part of them. This revision summarizes the most common side effects and consensus management to improve the compliance of therapies and patients' quality of life. Among the BRAF inhibitors, main cutaneous side effects are photosensitivity, plantar hyperkeratosis, and the appearance of verrucal keratosis or squamous cell carcinoma. Special attention must be paid to the development of new primary melanomas or changes on nevi during BRAF inhibitor therapy. The most common cutaneous side effects of immunotherapy are rash, pruritus, and vitiligo. It remains controversial the possible role of these toxicities as markers of response to therapy.

Dermoscopic assessment of skin toxicities in patients with melanoma during treatment with vemurafenib

Introduction

The use of vemurafenib in melanoma has improved the survival of patients; however, it is associated with skin toxicities.

Aim

To assess skin toxicities by dermoscopy in patients treated with vemurafenib.

Material and methods

Eight patients with BRAF V600 mutation positive metastatic melanoma were examined dermoscopically during vemurafenib treatment. All skin lesions occurring during therapy were assessed clinically and dermoscopically using a hand-held dermoscope with polarised and non-polarised light. Skin lesions suspected for malignancy appearing during therapy were totally surgically excised with consecutive histopathological examination.

Results

All 8 examined patients developed skin toxicity. The majority of patients (7/8) presented G1 skin toxicity according to CTCAE version 4.3. Only 1 of them had G2 skin toxicity. The most common dermoscopy findings in our study were hyperkeratotic verrucas in 5 patients (5/8) with structureless pattern. In some of them we also observed central dots, exophytic proliferation, hairpin vessels and homogeneous haemorrhage. Other findings were hyperkeratosis of the nipples (5/8) with brownish to yellowish, angular clods with a tendency to be more confluent in dermoscopy. Palmar plantar erythrodysaesthesia (3/8) showed dermoscopically a yellowish, homogeneous pattern. Four melanocytic skin lesions in 2 patients were surgically excised due to suspected malignant transformation. In most of them we observed an atypical pigmented network (abrupt cut-off, big holes), atypical globules and a homogeneous blue pattern; however, histopathological diagnosis excluded any malignancy.

Conclusions

Dermoscopy seems to be an easily performed and valuable method for assessment of skin toxicities during oncological therapy, at any time of the treatment.

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.

Melanocytic lesion evolution patterns with targeted therapies and immunotherapies for advanced metastatic melanoma: An observational study

BACKGROUND/OBJECTIVES

Various cutaneous side-effects have been reported with anti-melanoma systemic therapies. This study investigated the changes in melanocytic lesion pigmentation in patients on four different therapies.

METHODS

We analysed the serial dermatoscopic photographs of atypical melanocytic lesions taken from patients with advanced metastatic melanoma on four different systemic therapies (selective BRAF-inhibitor monotherapy, dabrafenib combined with trametinib [D&T], anti-programmed cell death protein 1 [anti-PD1] therapies, and anti-PD1 combined with ipilimumab) seen from February 2013 to May 2016. We compared these changes with the melanocytic lesions of 10 control patients.

RESULTS

In the control group, 19% of naevi lightened, 64% did not change and 17% darkened. Only the BRAF inhibitor group showed more darkened lesions than controls (37%, P < 0.001). Meanwhile, there were more lightened naevi in the D&T therapy group (86%, P < 0.001) as well as the anti-PD1 and ipilimumab groups (59%, P < 0.001) than controls. Patients on anti-PD1 monotherapy had more lightened (49%) and fewer darkened naevi (9%) than controls, but differences were not significant.

CONCLUSIONS

Our study showed that different anti-melanoma systemic therapies have different effects on the pigmentation of melanocytic lesions. BRAF inhibitor may have the propensity to cause darkening while D&T therapy and anti-PD1 caused lightening compared with controls. The findings emphasise the importance of regular dermatological monitoring in specialised clinics for patients on anti-melanoma systemic therapy. Clinicians should expect changes in the global pigmentation of melanocytic lesions but be suspicious of lesions with structural changes.

Melanocytic nevi and melanoma: unraveling a complex relationship

Approximately 33% of melanomas are derived directly from benign, melanocytic nevi. Despite this, the vast majority of melanocytic nevi, which typically form as a result of BRAF^V600E-activating mutations, will never progress to melanoma. Herein, we synthesize basic scientific insights and data from mouse models with common observations from clinical practice to comprehensively review melanocytic nevus biology. In particular, we focus on the mechanisms by which growth arrest is established after BRAF^V600E mutation. Means by which growth arrest can be overcome and how melanocytic nevi relate to melanoma are also considered. Finally, we present a new conceptual paradigm for understanding the growth arrest of melanocytic nevi in vivo termed stable clonal expansion. This review builds upon the canonical hypothesis of oncogene-induced senescence in growth arrest and tumor suppression in melanocytic nevi and melanoma.

Discriminating Nevi from Melanomas: Clues and Pitfalls

Reflectance confocal microscopy (RCM) together with dermoscopy enables improved differentiation of melanomas from most nevi. The resulting high sensitivity for detecting melanoma with RCM is complemented by a concomitant increased specificity, which results in the reduction of unnecessary biopsies of nevi. Although RCM can achieve high diagnostic accuracy for early melanoma detection, false-negative and false-positive cases of melanoma are occasionally encountered. This article reviews the essential clues and pitfalls for the diagnosis of melanoma via RCM and highlights the importance of evaluating RCM findings in light of the clinical scenario and dermoscopic features.

Drug-induced eruptive melanocytic nevi

INTRODUCTION

The sudden eruption of melanocytic nevi has been associated with a number of conditions, such as bullous skin diseases, immunodeficiency and immunosuppression. The exact mechanisms leading to the development of eruptive melanocytic nevi are unknown. Areas covered: The aim of this article is to review the literature concerning eruptive melanocytic nevi following the administration of immunosuppressive drugs and other medications. Expert opinion: The literature regarding the development of eruptive nevi in association with pharmacological therapies includes a relatively low number of reports. Prevalence of this phenomenon is likely to be underestimated, thus reporting should be encouraged in order to better define the actual significance and related clinical implications. The development of multiple melanocytic nevi during immunosuppressive treatments highlights the importance of immune system integrity in the regulation of nevi growth. The observation of eruptive nevi as an unexpected effect of targeted therapies for specific types of cancer, including melanoma, provided intriguing hints to understand the mechanisms underlying this paradoxical event. The synergistic role of additional triggers in the occurrence of drug-induced eruptive nevi has not been explored and may be an interesting area of research.

Brazilian guidelines for diagnosis, treatment and follow-up of primary cutaneous melanoma - Part II

The last Brazilian guidelines on melanoma were published in 2002. Development in diagnosis and treatment made updating necessary. The coordinators elaborated ten clinical questions, based on PICO system. A Medline search, according to specific MeSH terms for each of the 10 questions was performed and articles selected were classified from A to D according to level of scientific evidence. Based on the results, recommendations were defined and classified according to scientific strength. The present Guidelines were divided in two parts for editorial and publication reasons. In this second part, the following clinical questions were answered: 1) which patients with primary cutaneous melanoma benefit from sentinel lymph node biopsy? 2) Follow-up with body mapping is indicated for which patients? 3) Is preventive excision of acral nevi beneficious to patients? 4) Is preventive excision of giant congenital nevi beneficious to patients? 5) How should stages 0 and I primary cutaneous melanoma patients be followed?

Cobimetinib and vemurafenib for the treatment of melanoma

INTRODUCTION

Cobimetinib combined with vemurafenib is a new approved MEK inhibitor for first line treatment of metastatic melanoma patients with BRAF V600 mutations. It improves tumor response rates and progression free survival compared to vemurafenib alone, while decreasing toxicities due to the paradoxical activation of the MAPK signaling pathway.

AREAS COVERED

This review covers the pharmacology, efficacy, and toxicity data derived from clinical and preclinical studies on cobimetinib. It also reports ongoing trials evaluating cobimetinib to better understand future developments for this drug.

EXPERT OPINION

The combination of cobimetinib and vemurafenib seems to be more toxic than the combination therapy dabrafenib and trametinib even if these four drugs have never been compared in a randomized trial. The future of this combination depends on its capacity to be combined simultaneously or sequentially with immune based therapies to improve the durability of responses.

Genetics of melanocytic nevi

Melanocytic nevi are a benign clonal proliferation of cells expressing the melanocytic phenotype, with heterogeneous clinical and molecular characteristics. In this review, we discuss the genetics of nevi by salient nevi subtypes: congenital melanocytic nevi, acquired melanocytic nevi, blue nevi, and Spitz nevi. While the molecular etiology of nevi has been less thoroughly studied than melanoma, it is clear that nevi and melanoma share common driver mutations. Acquired melanocytic nevi harbor oncogenic mutations in BRAF, which is the predominant oncogene associated with melanoma. Congenital melanocytic nevi and blue nevi frequently harbor NRAS mutations and GNAQ mutations, respectively, while Spitz and atypical Spitz tumors often exhibit HRAS and kinase rearrangements. These initial 'driver' mutations are thought to trigger the establishment of benign nevi. After this initial phase of the cell proliferation, a senescence program is executed, causing termination of nevi growth. Only upon the emergence of additional tumorigenic alterations, which may provide an escape from oncogene-induced senescence, can malignant progression occur. Here, we review the current literature on the pathobiology and genetics of nevi in the hope that additional studies of nevi promise to inform our understanding of the transition from benign neoplasm to malignancy.

Dabrafenib: a new opportunity for the treatment of BRAF V600-positive melanoma

Prior to 2011, the 1-year survival rates for patients suffering from advanced or metastatic melanoma was as low as 33%, with a median overall survival of about 9 months. Several chemotherapeutic regimens have been applied, either as monochemotherapy or as polychemotherapy, overall not resulting in an improvement of progression-free or overall survival. Novel insights into the epidemiology and biology of melanoma allowed the development of newer therapies. The discovery of mutations in BRAF, a part of the mitogen-activated protein kinase, allowed the development of two BRAF inhibitors, vemurafenib and dabrafenib, which significantly improved the outcome of metastatic melanoma treatment. This article reviews the mechanism of action, efficacy, and safety profile of dabrafenib. An in-depth knowledge of this medication will encourage clinicians to select the appropriate therapeutic strategy for each patient, as well as to prevent or adequately manage side effects, optimizing, thus, the drug's applicability.

Managing Cutaneous Side Effects From Targeted Molecular Inhibitors for Melanoma and Nonmelanoma Skin Cancer

BACKGROUND

Targeted anticancer therapies can cause cutaneous adverse events different from classical chemotherapeutic toxicities.

OBJECTIVE

To review the literature on dermatologic adverse events (DAEs) of targeted molecular inhibitors for melanoma and nonmelanoma skin cancers with a focus on management options.

MATERIALS AND METHODS

A comprehensive literature search related to the side effects and management of these side effects from vemurafenib, dabrafenib, trametinib (BRAF inhibitors), pembrolizumab (antiprogrammed-death-receptor-1 antibody), imatinib (tyrosine kinase inhibitor), ipilimumab (anticytotoxic T-lymphocyte antigen-4 antibody), cetuximab (epidermal growth factor receptor inhibitor), sorafenib (multikinase inhibitor), and vismodegib (smoothened receptor inhibitor).

RESULTS

No large controlled studies specifically examining the management of DAEs of targeted molecular inhibitors exist, although there are case report-based recommendations and algorithms developed by expert panels to manage these adverse events.

CONCLUSION

Many options for managing the cutaneous side effects of targeted molecular inhibitors are similar to those used in general dermatology practice. When used effectively, drug dosing and patient quality of life may be optimized.

Cutaneous adverse effects of targeted therapies: Part II: Inhibitors of intracellular molecular signaling pathways

The last decade has spawned an exciting new era of oncotherapy in dermatology, including the development of targeted therapies for metastatic melanoma and basal cell carcinoma. Along with skin cancer, deregulation of the PI3K-AKT-mTOR and RAS-RAF-MEK-ERK intracellular signaling pathways contributes to tumorigenesis of a multitude of other cancers, and inhibitors of these pathways are being actively studied. Similar to other classes of targeted therapies, cutaneous adverse effects are among the most frequent toxicities observed with mitogen-activated protein kinase pathway inhibitors, PI3K-AKT-mTOR inhibitors, hedgehog signaling pathway inhibitors, and immunotherapies. Given the rapid expansion of these families of targeted treatments, dermatologists will be essential in offering dermatologic supportive care measures to cancer patients being treated with these agents. Part II of this continuing medical education article reviews skin-related adverse sequelae, including the frequency of occurrence and the implications associated with on- and off-target cutaneous toxicities of inhibitors of the RAS-RAF-MEK-ERK pathway, PI3K-AKT-mTOR pathway, hedgehog signaling pathway, and immunotherapies.

Cutaneous adverse events in patients treated with BRAF inhibitor-based therapies for metastatic melanoma for longer than 52 weeks

BACKGROUND

BRAF inhibitor-based therapies have been shown to induce cutaneous toxicities, with onset generally in the first 8-26 weeks of therapy.

OBJECTIVES

To determine whether cutaneous toxicities persist in patients who have remained on BRAF inhibitor-based therapies for longer than 52 weeks, and therefore whether ongoing dermatology assessment is required.

METHODS

All patients treated with the BRAF inhibitors vemurafenib or dabrafenib or combination BRAF inhibitor and mitogen-activated protein kinase kinase (MEK) inhibitor therapy at Westmead Hospital, Sydney, Australia underwent regular dermatological assessments for the duration of therapy. All patients enrolled in a clinical trial, and 18% of patients in the compassionate access scheme underwent a baseline assessment prior to commencement of therapy and every 4-8 weeks thereafter. Patients' adverse events were recorded in a specific database.

RESULTS

Patients continued to develop cutaneous adverse events after 52 weeks of continuous therapy. Patients on single-agent BRAF inhibitor therapy suffered from Grover disease (45%), plantar hyperkeratosis (45%), verrucal keratosis (18%) and even cutaneous squamous cell carcinoma (16%). The most frequent adverse event seen in patients in the combination BRAF and MEK inhibitor group was an acneiform eruption (40%).

CONCLUSIONS

Patients on BRAF inhibitor-based therapies need to continue to have regular dermatological follow-up independent of the duration of their therapy.

Melanocytic naevi with globular and reticular dermoscopic patterns display distinct BRAF V600E expression profiles and histopathological patterns

BACKGROUND

BRAF (v-raf murine sarcoma viral oncogene homologue B) V600E mutations have been detected with high frequency in melanocytic naevi. Few studies have stratified analyses by naevus dermoscopic pattern.

OBJECTIVES

To determine the frequency of BRAF V600E expression and histopathological pattern in acquired melanocytic naevi distinguished by a globular vs. reticular dermoscopic pattern.

METHODS

We retrospectively identified histologically proven melanocytic naevi with banal reticular or globular dermoscopic patterns and evaluated BRAF V600E expression using immunohistochemistry.

RESULTS

BRAF V600E expression was detected in 11 of 12 globular naevi vs. four of 13 reticular naevi (91·7% vs. 30·1%, P = 0·004). A predominantly dermal growth pattern (P < 0·001) and the presence of large junctional nests (P = 0·017) were each associated with a globular dermoscopic pattern. The presence of either a predominantly dermal growth pattern or large junctional nests was found in 13 of 15 naevi positive for BRAF V600E and in two of 10 naevi negative for BRAF V600E (86·7% vs. 20%, P = 0·002).

CONCLUSIONS

The frequency of BRAF V600E mutations differs in naevi distinguished by unique dermoscopic structures and microanatomical growth patterns. Globular naevi, which most often histologically correspond to a predominantly dermal growth pattern and/or the presence of large junctional nests, are significantly more likely to express BRAF V600E than reticular naevi. These preliminary results require validation, but may directly inform future studies of naevogenesis and melanoma genesis.

Dermatological toxicity associated with targeted therapies in cancer: optimal management

Targeted therapies have developed rapidly over the last few years in the field of oncology thanks to a better understanding of carcinogenesis. They target pathways involved in signal transduction (EGFR, HER2, HER3, HER4, FLT3, RAS, RAF, MEK, KIT, RET, mTOR, SRC, EPH, SCF), tumor angiogenesis (VEGFR, TIE2), and tumor microenvironment (PDGFR, FGFR). They rarely cause the systemic adverse reactions generally associated with chemotherapy, but frequently cause disabling and specific skin toxicity. The impact on patient quality of life can be important both in terms of symptoms caused and of potentially aesthetic consequences. Inappropriate management can increase the risk of dose reduction or discontinuation of the cancer treatment. In this review, we will discuss skin toxicity associated with the main drug classes-EGFR, BRAF, MEK, mTOR, c-KIT, CTLA4, and SMO inhibitors, and anti-angiogenic agents. Targeted therapy-induced skin toxicities will be detailed in terms of symptoms, frequency, evolution, complications, and topical and oral treatments in order to improve their diagnosis and management.

Treating advanced melanoma: current insights and opportunities

Whereas thin melanomas have an excellent prognosis after sufficient surgical treatment, melanoma disease in advanced stages is still a therapeutic challenge. After decades of frustrating studies, new therapeutic strategies have come up in the past few years. On the one hand, increasing insights into the molecular aberrations in melanoma have led to specific “targeted” therapies to affect only the mutated tumor cells, as in many other types of cancers. Today there are few “targeted” substances which are already approved and successfully used for single or combination therapy, but many others are under development. While on the other hand, nonpersonalized strategy substances have been developed successfully inducing an immunologic tumor response. Both kinds of therapy have been found to result in an improvement not only of the response rate, but also of the overall survival in metastatic disease, which represents a milestone in melanoma therapy. However, using these therapies there is still much to learn regarding the effects, the side effects, and the limitations of these promising substances.

Dormant melanomas or changing nevi?

The development of new primary melanomas in patients treated with vemurafenib has been reported recently in a study by Perier-Muzet et al. The primary outcome of the study was to describe the dermoscopic changes that prompted excision of those melanomas. However, the crucial point raised by the study is the large number of melanomas that were detected.