Dermatologic toxicities in epidermal growth factor receptor: a comprehensive pharmacovigilance study from 2013 to 2023

Epidermal growth factor receptor inhibitors (EGFRIs) induced cutaneous toxicity is a common adverse event (AE), although it is not as severe as major cancers, we still need to pay enough attention to them. Therefore, it is necessary to evaluate the diversity of EGFRI class drugs. The objective of this study was to conduct a scientific and systematic investigation into the correlation between EGFRI and cutaneous toxicities. The data accessed from the FDA adverse event reporting system database (FAERS) encompass a time frame spanning from January 2013 to March 2023. By utilizing reporting odds ratios (RORs), information components (ICs), proportional reporting ratios (PRRs), and chi-squared (χ2), the relationship between drugs and adverse reactions was evaluated through disproportionality analysis. Within the FAERS database, a total of 29,559 skin adverse events were recorded. A robust indication of the correlation between EGFRI and elderly patients (≥65 years) was identified. Among EGFRIs, erlotinib accounted for the largest proportion of skin adverse events (39.72%). Rash, dry skin, and pruritus ranked top among all preferred terms, and signals such as rash, skin lesions, and acneiform dermatitis were detected in every single drug. Clinicians should guide patients customize the treatment plan for each patient.

Erythema nodosum following treatment with dasatinib plus chemotherapy in a patient with myeloid blast phase of chronic myeloid leukemia

Erythema nodosum (EN) is a type of panniculitis occurring due to various conditions. It can be associated with certain malignancies or manifest as a side effect of drugs. This article presents a unique case of EN in a patient with chronic myeloid leukemia (CML-blast phase) following dasatinib and chemotherapy. Timely recognition and appropriate management are crucial to alleviate symptoms and consider potential drug-induced etiology.

Immunotherapy for keratinocyte cancers. Part II: Identification and management of cutaneous side effects of immunotherapy treatments

Keratinocytic cancers (KCs), specifically cutaneous squamous cell and basal cell carcinomas, can respond to topical, intralesional, or systemic immunotherapies, but cutaneous adverse events (CAEs) may occur. Understanding these risks, early recognition of these CAEs, and effective treatment may enable patients to continue their anticancer immunotherapies without dose impact. Immune checkpoint inhibitor-related CAEs after KCs can have multiple clinical presentations, with specific observed types including psoriasis and bullous pemphigoid. Cutaneous toxicities can require biopsies to confirm the diagnosis, especially in patients who are not responsive to topical or oral steroids, since the selection of biologic drugs depends on accurate diagnosis. Different types of CAEs from immune checkpoint inhibitors have been associated with different oncologic outcomes in various primary cancer types, and this remains to be determined for KC patients. CAE characterization and management after immune checkpoint inhibitors in KC patients is a rapidly growing field that needs specific and prospective studies.

Acneiform eruption induced by molecularly targeted agents in antineoplastic therapy: A review

BACKGROUND

Various biologic agents targeting specific molecules present new treatment options for various tumors. Acneiform eruption is a very common skin reaction to these agents. Although not life-threatening, acneiform eruption can affect patients' emotional and social lives. In very exceptional cases, it can lead to cancer therapy interruption.

AIMS

The aim of this study was to review the incidence rate, clinical characteristics, pathogenesis, and current management of acneiform eruption induced by molecularly targeted agents.

METHODS

This review was carried out through PubMed, Embase, and Cochrane searching terms 'acneiform eruption', 'papulopustular eruption' or 'acne-like rash' and 'skin toxicity', 'cutaneous toxicity', 'skin reactions', 'dermatological toxicities', 'target therapy,' or 'drug therapy'.

RESULTS

Of the 73 articles matched our search terms, 61 were original articles and 12 were case reports or case series. Acneiform eruption is most commonly observed in patients treated with epidermal growth factor receptor inhibitors and mitogen-activated protein kinase inhibitors. Typical lesions consist of erythematous papules and pustules without comedones, accompanying with burning, pruritus, or xerosis. The pathogenesis involves inflammation and abnormalities of the follicular epithelium, where a disorder in EGFR signaling plays a key role. The treatment of acneiform eruption depends on the severity of the rash.

CONCLUSIONS

Early recognition and effective management of this cutaneous adverse reaction can prevent unnecessary reduction and discontinuation of drug use and improve patient survival and quality of life. Close collaboration between oncologists and dermatologists is important to optimize therapy and improve patient survival.

Toxic epidermal necrolysis after the administration of enfortumab vedotin for urinary bladder urothelial carcinoma

Introduction

Enfortumab vedotin is a novel drug for locally advanced or metastatic urothelial carcinoma, but it is associated with a high incidence of skin reactions (up to 47.0%).

Case presentation

A 71-year-old male was administered enfortumab vedotin for bladder cancer associated with lymph node metastases. Slight erythema of the upper limbs appeared on Day 5. Erythema gradually worsened. On Day 8, second administration was performed. On Day 12, based on the extents of blisters, erosion, and epidermolysis, a diagnosis of toxic epidermal necrolysis was made. The patient died of multiple organ failure on Day 18.

Conclusion

As serious cutaneous toxicity may appear early after the start of administration, it is important to consider the timing of the second administration of the initial course carefully. In cases of skin reaction, reduction or discontinuation should be considered.

The value of the multidisciplinary team in metastatic renal cell carcinoma: Paving the way for precision medicine in toxicities management

The new landscape of treatments for metastatic clear cell renal carcinoma (mRCC) is constantly expanding, but it is associated with the emergence of novel toxicities, adding to up to those observed in the tyrosine-kinase inhibitor (TKI) era. Indeed, the introduction of immune checkpoint inhibitors (ICIs) alone or in combination has been associated with the development of immune-related adverse events (irAEs) involving multiple-organ systems which, even if rarely, had led to fatal outcomes. Moreover, due to the relatively recent addition of ICIs to the previously available treatments, the potential additive adverse effects of these combinations are still unknown. A prompt recognition and management of these toxicities currently represents a fundamental issue in oncology, since it correlates with the outcome of cancer patients. Even if clinical guidelines provide indications for the management of irAEs, no specific protocol to evaluate the individual risk of developing an adverse event during therapy is currently available. A multidisciplinary approach addressing appropriate interventions aimed at reducing the risk of any insidious, severe, and/or dose-limiting toxicity might represent the most efficacious strategy to timely prevent and manage severe irAEs, allowing indirectly to improve both patients' cancer-specific survival and quality of life. In this review, we reported a five-case series of toxicity events that occurred at our center during treatment for mRCC followed by the remarks of physicians from different specialties, pinpointing the relevant role of an integrated and extended multidisciplinary team in a modern model of mRCC patient management.

Cutaneous side effects and types of dermatological reactions in metastatic melanoma patients treated by immunotherapies or targeted therapies: A retrospective single center study

Immunotherapy and target therapy have revolutionized treatment of stage III/IV melanoma. Both treatments show a favorable toxicity profile even if cutaneous adverse events (AEs) are frequent (30%-40% of cases). This is a retrospective single center cohort study that included patients with stage IV or inoperable stage III metastatic melanoma (AJCC 8th) who received BRAFi + MEKi therapy or immunotherapy with Checkpoint inhibitors. All cutaneous AEs were ascertained by a dermatologist based on clinical and histological findings. The primary outcome was to provide a detailed clinical dermatological classification of cutaneous adverse events and an evaluation of the incidence of skin toxicity in the two arms of therapy (immunotherapy and target therapy). A total of 286 patients with stages III-IV metastatic melanoma were included: 146 received immunotherapy and 140 target therapy. In the immunotherapy cohort, 63 (43.1%) cutaneous reactions were observed while 33 skin reactions (23.6%) were identified in patients treated with target therapy. All the skin toxicities observed were grade I, excepted four cases: an erythema multiforme-like eruption, a grade III psoriasis and two grade III maculopapular rashes. Immunotherapy in older age resulted statistically related to skin toxicities (p = 0.011), meanly in metastatic setting (p = 0.011). Cumulative incidence of skin toxicities was 65.63% in immunotherapy cohort (p = 0.001). Also multivariate logistic regression shows a significant association between skin adverse events and immunotherapy (odds ratio [OR] = 0.50; 95% confidence interval [CI]: 0.29-0.85, p: 0.01) and between cutaneous AEs and metastatic setting (OR = 1.97; 95% CI: 1.04-3.74, p: 0.04). We have also shown that as the age of initiation of therapy increases the probability of developing skin toxicity grows. However, stratifying by type of therapies the effect of age persists only in immunotherapy (OD: 1.04; CI: 1.01-1.06; p: 0.04) while for target therapy age does not affect the onset of skin toxicity (OD 1.01; CI 0.98-1.04; p = 0.42). No differences were shown between patients on target therapy and immunotherapy regarding gender. Patients were also evaluated regarding concomitant therapies and seems that Levotyroxine may be involved in AEs during immunotherapy treatment. More studies are needed to deepen this aspect, also considering the medical history and diverse drug associations. Cutaneous adverse events are characterized by heterogeneous manifestations, are more often seen in patients on immunotherapy and dermatologists can play a crucial role in multidisciplinary care.

Decreased HMGB1 expression contributed to cutaneous toxicity caused by lapatinib

The application of lapatinib, a widely used dual inhibitor of human epidermal growth factor receptor 1 (EGFR/ERBB1) and 2 (HER2/ERBB2), has been seriously limited due to cutaneous toxicity. However, the specific mechanism of lapatinib-induced cutaneous toxicity has not been clarified, leading to the lack of an effective strategy to improve clinical safety. Here, we found that lapatinib could induce mitochondrial dysfunction, lead to DNA damage and ultimately cause apoptosis of keratinocytes. In addition, we found that lapatinib could induce an aberrant immune response and promote the release of inflammatory factors in vitro and in vivo. Mechanistically, downregulated expression of the DNA repair protein HMGB1 played a critical role in these toxic reaction processes. Overexpression of HMGB1 inhibited keratinocyte apoptosis and inflammatory reactions. Therefore, restoring HMGB1 expression might be an effective remedy against lapatinib-induced cutaneous toxicity. Finally, we found that saikosaponin A could significantly rescue the reduced HMGB1 transcription, which could alleviate lapatinib-induced DNA damage, inhibit keratinocyte apoptosis and further prevent the toxicity of lapatinib in mice. Collectively, our study might bring new hope to clinicians and tumor patients and shed new light on the prevention of cutaneous adverse drug reactions induced by EGFR inhibitors.

Remodeling of dermal adipose tissue alleviates cutaneous toxicity induced by anti-EGFR therapy

Anti-epidermal growth factor receptor (EGFR) therapy–associated cutaneous toxicity is a syndrome characterized by papulopustular rash, local inflammation, folliculitis, and microbial infection, resulting in a decrease in quality of life and dose interruption. However, no effective clinical intervention is available for this adverse effect. Here, we report the atrophy of dermal white adipose tissue (dWAT), a highly plastic adipose tissue with various skin-specific functions, correlates with rash occurrence and exacerbation in a murine model of EGFR inhibitor-induced rash. The reduction in dWAT is due to the inhibition of adipogenic differentiation by defects in peroxisome proliferator-activated receptor γ (PPARγ) signaling, and increased lipolysis by the induced expression of the lipolytic cytokine IL6. The activation of PPARγ by rosiglitazone maintains adipogenic differentiation and represses the transcription of IL6, eventually improving skin functions and ameliorating the severity of rash without altering the antitumor effects. Thus, activation of PPARγ represents a promising approach to ameliorate cutaneous toxicity in patients with cancer who receive anti-EGFR therapy.

Cutaneous toxicity of FDA-approved small-molecule kinase inhibitors

INTRODUCTION

By 1 January 2021, the FDA has approved a total of 62 small-molecule kinase inhibitors (SMKIs). The increasing clinical use of small-molecule kinase inhibitors has led to some side effects, the most common of which is cutaneous toxicity, as reflected by approximately 90% (57 of 62) of the FDA-approved SMKIs have reported treatment-related cutaneous toxicities. Since these cutaneous toxicities may have a crucial influence on the emotional, physical and psychosocial health of the patients, it is of great importance for doctors, patients, oncologists and interrelated researchers to be aware of the cutaneous side effects of these drugs in order to make the diagnosis accurate and the treatment appropriate.

AREAS COVERED

This review aims to summarize the potential cutaneous toxicities and the frequency of occurrence of FDA-approved 62 SMKIs, and provide a succinct overview of the potential mechanisms of certain cutaneous toxicities. The literature review was performed based on PubMed database and FDA official website.

EXPERT OPINION

It is significant to determine the risk factors for SMKI-induced cutaneous toxicity. The mechanisms underlying SMKI-induced cutaneous toxicities remain unclear at present. Future research should focus on the mechanisms of SMKI-induced cutaneous toxicities to find out mechanistically driven therapies.

Dermatologic adverse events associated with targeted therapies for melanoma

INTRODUCTION

The development of new targeted therapies has considerably changed the therapeutic paradigm of melanoma, significantly increasing overall survival (OS) and progression-free survival (PFS). However, skin-related adverse sequelae might occur and impact on patients' quality of life.

AREAS COVERED

In this article we will cover the most important dermatological toxicities related to BRAF and MEK-inhibitors, along with updated management strategies.

EXPERT OPINION

BRAF inhibitors have represented a revolution in the treatment of melanoma. They have improved the outcome of the disease and therefore represent an important option in the management and care of patients with advanced melanoma. Skin toxicity (especially the onset of squamous skin carcinomas) has been considered a major cutaneous side effect and, although the addition of MEK inhibitors in combination has significantly reduced the incidence of skin sequelae, serious skin adverse events might develop anyway and impact significantly on patients'quality of life and on national health system budget. The introduction of BRAF and MEK inhibitors as a new effective adjuvant treatment option for stage III and ulcerated melanoma has proved a significant impact on the risk of recurrence, and may have interesting developments in the near future as a further therapeutic tool.

Cutaneous reactions to pediatric cancer treatment part II: Targeted therapy

Cancer remains a leading cause of morbidity and mortality among children. Targeted therapies may improve survivorship; however, unique side-effect profiles have also emerged with these novel therapies. Changes in hair, skin, and nails-termed dermatologic adverse events (AEs)-are among the most common sequelae and may result in interruption or discontinuation of therapy. Though dermatologic AEs have been detailed in adults, these findings are not well described in the pediatric population. We reviewed the literature to characterize dermatologic AEs to anticancer targeted therapies available as of July 2020 and summarized the spectrum of clinical findings as well as treatment recommendations for children. Dermatologic AEs are among the most common AEs reported in pediatric patients receiving targeted therapy, but morphologic and histologic descriptions are often lacking in current publications. Pediatric dermatologists are uniquely poised to recognize specific morphology of dermatologic AEs and make recommendations for prevention and treatment that may improve quality of life and enable ongoing cancer therapy.

Adverse Effects of Immune-Checkpoint Inhibitors in Hepatocellular Carcinoma

Immune-modulatory therapy, especially with immune-checkpoint inhibitors (ICIs), has reshaped cancer therapeutics. Immunotherapy is relatively a novel approach that can effectively delay the progression of aggressive tumors and inhibit tumor recurrence and metastasis in many different tumor types. In the past years, ICIs have shown a sustained response and promising long-term survival in patients with advanced hepatocellular carcinoma (HCC). Nevertheless, ICI therapy can unbalance the immune system and result in a wide range of immune-related adverse events (irAEs), which are generally manageable but occasionally lead to a fatal outcome. HCC generally develops in the context of liver cirrhosis which is typically caused by viral hepatitis and non-alcoholic steatohepatitis. These underlying diseases may cause symptoms that overlap with irAEs and lead to consequences such as late recognition, inadequate work-up, and inappropriate treatment. Owing to the growing use of immunotherapy in HCC, it is necessary for clinicians to strengthen their understanding of the frequency, clinical features, and management of irAEs. This review focuses on the common toxicities associated with ICI therapy in patients with HCC and summarizes therapeutic strategies that can be used to monitor and manage such toxicities.

Comparison between two premedication regimens of dexamethasone before a pemetrexed-based chemotherapy: A single-center experience study

Pemetrexed, frequently used for the treatment of pulmonary adenocarcinoma, may cause cutaneous reactions that can be reduced with three oral doses of dexamethasone starting the day before treatment, and continuing after chemotherapy for a number of doses which varies according to the emetogenic potential of the protocol. Dexamethasone may induce side effects and no guideline suggests the conduct to favor when dexamethasone doses are omitted before treatment with pemetrexed. This study was performed to evaluate the efficacy of a simplified regimen of dexamethasone administered before a pemetrexed-based chemotherapy in preventing cutaneous toxicities. A prospective study was conducted with patients starting a pemetrexed-based treatment between February 2016 and August 2017 at the ambulatory oncology clinic of an academic hospital. Patients were divided into two groups, one receiving the usual oral premedication and the other receiving a 20-mg intravenous dose of dexamethasone prior to chemotherapy. Among the 70 patients included, 39 received the alternative regimen prior to a total of 114 chemotherapy cycles, while the other 31 patients received the usual premedication before a total of 154 cycles. The cutaneous toxicity incidence was of 10 events in the simplified treatment group compared to 9 events in the standard group (p = 0.35). These events occurred in nine patients within the experimental group and five patients within the control group (p = 0.56). A single intravenous dexamethasone regimen represents a valid alternative to the usual prophylaxis in preventing cutaneous reactions.

Combined immune therapy grade IV dermatitis in metastatic melanoma

Checkpoint inhibition is the mainstay of treatment in metastatic melanoma. More recently combined cytotoxic T-lymphocyte antigen-4 and programmed-death-1 blockade has resulted in improved response rates and overall survival in treatment naïve patients compared to monotherapy albeit with increased rates of adverse events. Dermatologic toxicities are an emerging consequence of the use of checkpoint inhibitors and have reportedly been more prevalent with the use of combined therapy. However, grade 3 and 4 adverse event rates are still less than 5%. Here, we report a case of a 63-year-old Caucasian male with metastatic melanoma treated with first line combined ipilimumab and nivolumab who then developed a steroid refractory, biopsy confirmed pityriasis lichenoides-like, drug related rash that resolved with cyclosporine. Time of onset was 24 days and presenting symptoms demonstrated a maculopapular rash presenting over the back and chest with pruritus. Unfortunately, the patient subsequently had multi-organ failure with acute kidney injury requiring dialysis, hypotension requiring vasopressor support, hepatic dysfunction, and bilateral lung infiltrates resulting in a fatal outcome. This case report highlights the effective use of cyclosporine as an immunomodulatory agent in the management of severe dermatological toxicity due to combination immunotherapy.

Thiotepa-induced cutaneous toxicity in pediatric patients: Case report and implementation of preventive care guidelines

Thiotepa, a highly lipophilic, alkylating agent, and/or its active metabolites may be excreted in part via skin in patients receiving high-dose therapy. We present a case of cutaneous toxicity observed in a 4.5-year-old girl patient with medulloblastoma treated with a high-dose thiotepa conditioning regimen before autologous stem cell transplantation. Skin lesions, as well as their pattern and locations, were evocative of thiotepa toxidermia. After the case herein described, preventive care guidelines were implemented in our unit as from 2014. A retrospective follow-up of 26 pediatric patients receiving thiotepa prior to stem cell transplantation was performed until March 2018. In this series of patients, only one patient experienced cutaneous toxicity as reported herein. Thereafter, only mild cutaneous toxicity was observed, even with double or triple transplantation protocols with high-dose thiotepa. Clear preventive care instructions should be detailed in the Summary of Product Characteristics in order to minimize the cutaneous toxicity of thiotepa.

Cutaneous toxicity as a predictive biomarker for clinical outcome in patients receiving anticancer therapy

The relationship between treatment outcome and cutaneous toxicity induced by anticancer therapy has gained attention in the past decade. In this article, we have provided an overview of the 3 main classes of anticancer agents-specifically, molecularly targeted kinase inhibitors, immune checkpoint inhibitors, and cytotoxic chemotherapeutics-and described the data evaluating the association between cutaneous toxicity induced by these agents and survival benefit. Although preliminary studies are promising with regard to the potential role of cutaneous toxicities as a surrogate biomarker of efficacy of treatment, larger prospective studies are needed to confirm this relationship. Dermatologists have a unique opportunity to collaborate with oncologists in the multidisciplinary treatment paradigm by helping to identify and manage these dermatologic events in patients with cancer. A heightened awareness of these toxicities is critical, as it can potentially allow recognition of the efficacy of anticancer therapy and may influence treatment decisions and patient outcomes.

Afatinib-Associated Cutaneous Toxicity: A Correlation of Severe Skin Reaction with Dramatic Tumor Response in a Woman with Exon 19 Deletion Positive Non-Small-Cell Lung Cancer

Epidermal growth factor receptor (EGFR) inhibitors are biological factors used in the treatment of non-small-cell lung cancers (NSCLC) that are positive for EGFR mutations. Afatinib is one such drug that has been approved for use in this capacity. Cutaneous toxicity is the second most commonly reported adverse event with the use of afatinib. A 39-year-old woman with inoperative right lung adenocarcinoma was initially treated with afatinib. She not only developed a severe papulopustular eruption but also had a dramatic reduction of her tumor. Her cutaneous symptoms and lesions were effectively treated with oral and topical corticosteroids, oral antibiotics, and oral antihistamines. After one month of afatinib treatment, her tumor was resected, and there was no evidence of metastases. Afatinib-induced cutaneous toxicity has a positive correlation with tumor response to anti-neoplastic therapy. Supplemental systemic and topical treatments can be initiated to palliate adverse skin events in order to enable adequate duration of treatment with afatinib.

A Case of Drug-induced Cutaneous Toxicity Observed in Cynomolgus Monkeys

The purpose of this article is to describe a case of drug-induced cutaneous toxicity observed in cynomolgus monkeys and to introduce approaches attempted in order to elucidate mechanisms. The test article was a small molecule with a ubiquitously distributed target, especially in rapidly dividing cells, and which modulated cell cycle regulation. After 7 consecutive days of oral dosing, animals developed multifocal skin lesions. The lesions were characterized clinically by vesicles and scabs formation and were distributed mainly in thin-skinned areas of the body including the cheek, chest, abdomen, and inner limbs. Microscopically, the lesions were confirmed as epidermal vesicle formation and ulceration. Immunohistochemical staining revealed that the levels within the epidermis where separation (vesicle formation) occurred were not consistent. The differential diagnoses for vesicular skin lesions and our efforts to elucidate the mechanism of toxicity using in-house database searches and immunohistochemistry are discussed. To the best of our knowledge, similar cutaneous toxicity has not been reported previously, although there are reports of other types of cutaneous toxicities. Understanding the mechanisms of the toxicity is very important when assessing human relevancy during drug development. Our investigative approach can be utilized when unusual skin toxicities are observed in the future.

Bleomycin Containing Chemotherapeutic Regimen Induced Acquired Partial Lipodystrophy

Bleomycin toxicity predominantly affects the skin and lungs. Cutaneous toxicity classically known to present with bleomycin are flagellate erythema and drug rash. We hereby report an isolated case of (bleomyicn)-induced acquired partial (lipodytrophy) having potential cosmetic implications in a young women prescribed postoperatively following a case of germ cell carcinoma of ovary (endodermal sinus tumor).

A spectrum of cutaneous toxicities from erlotinib may be a robust clinical marker for non-small-cell lung therapy: a case report and literature review

Some literature suggests that an EGFR inhibition-induced rash can be used as a clinical marker, but few studies report the correlation between a spectrum of cutaneous toxicities from EGFR inhibition and drug efficacy. We report about a woman with a stage IV lung adenocarcinoma using erlotinib monotherapy, who experienced a spectrum of cutaneous toxicities, including papulopustular rash, mucositis, pruritus, xerosis, paronychia, and facial hirsutism. With treatment, her metastatic lesions shrunk remarkably. This report suggests that some non-small-cell lung cancer patients experiencing a spectrum of cutaneous toxicities might have a good tumor response using erlotinib monotherapy. Our findings may provide a method for clinicians to predict erlotinib efficacy in non-small-cell lung cancer therapy without knowledge of the EGFR mutation status.

Vemurafenib and panitumumab combination tailored therapy in BRAF-mutated metastatic colorectal cancer: a case report

As the knowledge on cancer genetic alterations progresses, it fosters the need for more personalized therapeutic intervention in modern cancer management. Recently, mutations in KRAS, BRAF, and PIK3CA genes have emerged as important mechanisms of resistance to EGFR-targeted therapy in metastatic colorectal cancer (mCRC). Here we report the first case of a mCRC patient whose disease had progressed on standard lines of treatment and for which we devised a personalized therapeutic approach consisting of vemurafenib (Zelboraf) and panitumumab (Vectibix), based on the following molecular profile: BRAF(V600E)-mutant, amplified EGFR (double positive) and WT KRAS, WT PIK3CA, not-amplified HER2 (triple negative). This new combination therapy was well tolerated and resulted in a strong control of the disease. In particular, the vemurafenib-panitumumab combination appears to limit the typical toxicity of single agents, since no cutaneous toxic effects typically associated with vemurafenib were observed. Here we report the first clinical evidence that the combination of an anti-EGFR (panitumumab) and an inhibitor of BRAF(V600E) (vemurafenib) is well tolerated and results in a strong disease control in an extensively pretreated mCRC patient.