Dermatologic toxicities to inhibitors of cyclin-dependent kinases CDK 4 and 6: An updated review for clinical practice

Cyclin-dependent kinase (CDK) 4/6 inhibitors (palbociclib, ribociclib and abemaciclib) have revolutionized the treatment of metastatic breast carcinoma. They currently form the first-line treatment, in combination with endocrine agents, for the management of locally advanced or metastatic hormone receptor-positive (HR + ), human epidermal growth factor receptor 2-negative (HER2-) breast cancer, the largest subtype of breast carcinoma. CDK 4/6 inhibitors have shown comparable efficacy outcomes with predictable and manageable adverse events. In this setting, dermatologic toxicity appears to be relatively frequent, accounting for up to 15% of all reported adverse events. It is usually mild to moderate in intensity and does not normally constitute a dose-limiting toxicity. The range of dermatologic adverse events includes both non-specific entities (maculopapular rash, pruritus, alopecia) and more characteristic toxicities related to CDK4/6 inhibitors, such as vitiligo-like lesions or cutaneous lupus erythematosus. Finally, more severe or life-threatening skin reactions can occasionally occur. The main dermatologic manifestations associated with CDK4/6 inhibitors, as well as management thereof, are described in this comprehensive review.

Oral mucosal toxicities induced by immune checkpoint inhibitors: Clinical features and algorithm management

Immune checkpoint inhibitors (ICIs) have emerged as standard therapies for an increasing number of advanced cancers. Nonspecific immune activation may lead to immune-related adverse events among which dermatological reactions are one of the most prevalent (all-grade incidence ranging from 30 to 60%). Oral mucosal adverse reactions to ICIs are far less common than cutaneous adverse events. However, a spectrum of oral changes with characteristic features has recently emerged, including lichenoid reactions, sicca syndrome, and even autoimmune bullous disorders with oral involvement. Oral changes mainly occur during the first year of treatment, often concurrently with other dermatological changes, and may involve up to 10% of patients under ICI therapies. This article provides a systematic review of the oral changes reported with these therapies based on a rich iconography.

Anticancer treatments and photosensitivity

Drug‐induced photosensitivity is associated with a wide range of anticancer treatments, including conventional chemotherapeutic agents, targeted anticancer therapies, and immune checkpoint inhibitors. These dermatologic adverse events can have a major impact on the well‐being and quality of life of cancer patients, leading to dose modifications and interruption or discontinuation of anticancer treatments in severe cases. However, the heterogeneous nature of the photosensitive reactions induced by these agents, as well as the common concomitant use of other potentially photosensitizing drugs (antibiotics, voriconazole, nonsteroidal anti‐inflammatory drugs, etc.), can make the diagnosis and, therefore the prevention, of these adverse events particularly challenging. The aim of this review is to describe the most characteristic forms of photosensitivity observed in patients being treated with anticancer treatments, including phototoxicity and photoallergy, and other potentially photo‐induced manifestations such as UV recall, exaggerated sunburn reactions associated with treatment‐related vitiligo, drug‐induced cutaneous lupus erythematosus, and UV‐induced hyperpigmentation. We also discuss the photosensitive reactions recently reported with new‐generation targeted anticancer therapies and immune checkpoint inhibitors and highlight the importance of continued surveillance to identify photosensitizing agents, and of educating patients on the need for preventive UVA/UVB photoprotective measures.

French guidelines for the management of oral lichen planus (excluding pharmacological therapy)

INTRODUCTION

Oral lichen is a chronic inflammatory disease for which diagnostic management and follow-up are heterogeneous given the absence of specific guidelines in France. Our objective was to develop French multidisciplinary guidelines for the management of oral lichen.

MATERIALS AND METHODS

Working groups from the Groupe d'Etude de la Muqueuse Buccale (GEMUB) formulated a list of research questions and the corresponding recommendations according to the "formal consensus" method for developing practice guidelines. These recommendations were submitted to a group of experts and the degree of agreement for each recommendation was assessed by a scoring group.

RESULTS

Twenty-two research questions, divided into 3 themes (nosological classification and initial assessment, induced oral lichenoid lesions, and follow-up) resulted in 22 recommendations. Initial biopsy for histology is recommended in the absence of reticulated lesions. Biopsy for direct immunofluorescence is recommended for ulcerated, erosive, bullous types and for diffuse erythematous gingivitis. Management should include a periodontal and dental check-up, and investigation for extra-oral lesions. Hepatitis C testing is recommended only if risk factors are present. Definitions, triggering factors and the management of "induced oral lichenoid lesions" were clarified. Oral lichen must be monitored by a practitioner familiar with the disease at least once a year, using objective tools.

CONCLUSION

This formalised consensus of multidisciplinary experts provides clinical practice guidelines on the management and monitoring of oral lichen.

European recommendations for management of immune checkpoint inhibitors-derived dermatologic adverse events. The EADV task force 'Dermatology for cancer patients' position statement

The introduction of immune checkpoint inhibitors (ICIs) opened a new era in oncologic therapy. The favourable profile of ICIs in terms of efficacy and safety can be overshadowed by the development of immune-related adverse events (irAEs). Dermatologic irAEs (dirAEs) appear in about 40% of patients undergoing immunotherapy and mainly include maculopapular, psoriasiform, lichenoid and eczematous rashes, auto-immune bullous disorders, pigmentary disorders, pruritus, oral mucosal lesions, hair and nail changes, as well as a few rare and potentially life-threatening toxicities. The EADV task force Dermatology for Cancer Patients merged the clinical experience of the so-far published data, incorporated the quantitative and qualitative characteristics of each specific dirAEs, and released dermatology-derived, phenotype-specific treatment recommendations for cutaneous toxicities (including levels of evidence and grades of recommendation). The basic principle of management is that the interventions should be tailored to serve the equilibrium between patients' relief from the symptoms and signs of skin toxicity and the preservation of an unimpeded oncologic treatment.

[Immune-related adverse events after immune checkpoints inhibitors in 2019: An update]

Use of checkpoint inhibitors to treat cancer was one of the most important revolution these last years and an increasing number of new types of tumors is currently under investigation with these new treatments. However, immune-related adverse events associated with these agents frequently affect various organs, mimicking auto-immune or inflammatory diseases. Some of these effects can be severe, often requiring hospitalization and specialized treatment (immunosuppression). Most known agents are ipilimumab (anti-CTLA-4 antibody) nivolumab and pembrolizumab (anti-PD-1 antibodies). New molecules are now approved or in development as anti-PD-L1 antibodies, anti-LAG-3 or anti-TIM-3 antibodies, increasing the probability and new description of immune-related adverse events. With his experience in auto-immune diseases, the immunologist/internal medicine specialist has an important role in the management of these toxicities. The goal of this review is to focus on the incidence, diagnostic assessment and recommended management of the most relevant immune-related adverse events.

[Dermatologic toxicities of immune checkpoint inhibitors]

The development of immune checkpoint inhibitors (monoclonal antibodies targeting PD-1/PD-L1 or CTLA-4) represents a significant advance in the treatment of multiple cancers. Given their particular mechanism of action, which involves triggering CD4+/CD8+ T-cell activation and proliferation, they are associated with a specific safety profile. Their adverse events are primarily immune-related, and can affect practically all organs. In this context, dermatological toxicity is the most common, though it mostly remains mild to moderate and does not require discontinuation of treatment. More than a third of patients are faced with cutaneous adverse events, usually in the form of a maculopapular rash, pruritus or vitiligo (only in patients treated for melanoma). Much more specific dermatologic disorders, however, may occur such as lichenoid reactions, induced psoriasis, sarcoidosis, auto-immune diseases (bullous pemphigoid, dermatomyositis, alopecia areata), acne-like rash, xerostomia, etc. Rigorous dermatological evaluation is thus mandatory in the case of atypical, persistent/recurrent or severe lesions. In this article, we review the incidence and spectrum of dermatologic adverse events reported with immune checkpoint inhibitors. Finally, a management algorithm is proposed.

[Uncommon dermatologic disorders triggered by radiation therapy of breast cancer: A case-series]

Radiotherapy's main skin toxicities are now well-separated, acute (acute radiation dermatitis) or chronic complications (chronic radiation dermatitis, induced cutaneous carcinoma, aesthetic sequelae). Exceptionally, radiotherapy may induce, by isomorphic reaction or Koebner's phenomenon, some specific dermatosis. In this article, we report five new observations of these unusual complications of radiation therapy, occurring in very variable time after breast irradiation and remaining strictly localized in the irradiated field (cutaneous mastocytosis, Sweet syndrome, lichen planus, vitiligo). These cases emphasize the need to realize a systematic histological exam if any atypical skin lesion appears after radiotherapy, even long after.

Immune-related alopecia (areata and universalis) in cancer patients receiving immune checkpoint inhibitors

Cytotoxic T-lymphocyte-associated protein-4, programmed cell death protein and programmed cell death protein ligand 1 monoclonal antibodies (immune checkpoint inhibitors), are used to treat various malignancies. Their mechanism of action involves the inhibition of negative regulators of immune activation, resulting in immune-related adverse events (irAEs) including endocrinopathies, pneumonitis, colitis, hepatitis and dermatological events. Dermatological irAEs include maculopapular rash, pruritus, vitiligo, blistering disorders, mucocutaneous lichenoid eruptions, rosacea and the exacerbation of psoriasis. Alopecia secondary to immune checkpoint inhibitors has been reported in 1·0-2·0% of treated patients. Our objective is to characterize for the first time the clinicopathology of patients with alopecia areata (AA) secondary to immune checkpoint inhibitors, including the first report of anti-PD-L1 therapy-induced AA, and review of the literature. Four cases of patients who developed partial or complete alopecia during treatment with immune checkpoint inhibitors for underlying cancer were identified from our clinics. Methods include the review of the history and clinicopathologic features. Three patients (75%) had AA and one had universalis. Two patients had a resolution after topical, oral or intralesional therapies and one had a resolution after immunotherapy was discontinued; all regrown hair exhibited poliosis. One of the four patients had coincident onychodystrophy. This report describes a series of four patients who developed partial or complete alopecia (i.e. areata and universalis) during treatment with immune checkpoint inhibitor therapies for cancer. The recognition and management of hair-related irAEs are important for pretherapy counselling and interventions that contribute to maintaining optimal health-related quality of life in patients.