Oral health in oncology: impact of immunotherapy

Cutaneous Side Effects of Modern Targeted Therapy and Immunotherapy in Patients with Dermatological Malignancies

The advent of immunotherapy and targeted therapies in treating dermatological malignancies has dramatically changed the landscape of dermato-oncology in recent years. Their superior efficacy compared to previous therapeutic options, such as chemotherapy, has resulted in their use in treating devastating malignancies, such as melanoma or unresectable/metastatic basal cell and squamous cell carcinoma. Skin toxicity is a critical safety consideration, among other adverse reactions, that can occur under treatment with these agents. This article aims to summarize the cutaneous side effects of immune checkpoint inhibitors and targeted dermato-oncological therapies. Although the skin side effects of these agents are primarily mild, they can occasionally affect the decision for treatment continuation and the quality of life of the affected patients. Therefore, physicians must be acquainted with the specific cutaneous toxicity profile of such treatments to mitigate their impact on the patients and optimize the overall outcome of dermato-oncological therapy.

An Overview of Clinical Oncology and Impact on Oral Health

As the incidence of cancer continues to increase, so too will the use of various forms of cancer therapeutics and their associated oral and dental complications. Although many of the acute and chronic oral toxicities of cancer therapy are largely unavoidable, appropriate and timely management of these complications has the potential to alleviate morbidity and improve outcomes. Undoubtedly, the substantial short- and long-term impacts of cancer therapy on the health of the oral cavity requires increased awareness, prevention, and treatment by multidisciplinary healthcare teams consisting of medical oncologists, dentists, and other oral healthcare specialists. This mini review provides a brief purview of the current state of clinical oncology and its impact on oral health. The topics introduced here will be further investigated throughout the remainder of the "Oral Complications in Cancer Patients" mini-review series.

Oral Complications of Head and Neck Cancer Therapy

Current therapies for Head and Neck cancer treatment are extremely advanced. Though, they cause oral complications which have deleterious effects on basic life functions, affect oral and overall health, may lead to significant morbidity and treatment discontinuation and have an impact on survivorship and quality of life. As new therapies are introduced, a new spectrum of oral complications is rising, compromising the mucosal integrity and the salivary function, that may not be recognized, reported and treated properly. Oral complications, often permanent and extremely painful, may include mucositis, xerostomia, dysgeusia, infections, trismus and fibrosis, risk of dental disease and necrosis of the jaw, neurosensory disorders and when targeted therapies and immunotherapy are involved, aphthoid and lichenoid lesions can also be reported. Increased awareness is required for the prevention and management of these complications, which can be best provided by a multidisciplinary team.

Immune checkpoint inhibitor-related dermatologic adverse events

Immune checkpoint inhibitors have emerged as a pillar in the management of advanced malignancies. However, nonspecific immune activation may lead to immune-related adverse events, wherein the skin and its appendages are the most frequent targets. Cutaneous immune-related adverse events include a diverse group of inflammatory reactions, with maculopapular rash, pruritus, psoriasiform and lichenoid eruptions being the most prevalent subtypes. Cutaneous immune-related adverse events occur early, with maculopapular rash presenting within the first 6 weeks after the initial immune checkpoint inhibitor dose. Management involves the use of topical corticosteroids for mild to moderate (grades 1-2) rash, addition of systemic corticosteroids for severe (grade 3) rash, and discontinuation of immunotherapy with grade 4 rash. Bullous pemphigoid eruptions, vitiligo-like skin hypopigmentation/depigmentation, and psoriasiform rash are more often attributed to programmed cell death-1/programmed cell death ligand-1 inhibitors. The treatment of bullous pemphigoid eruptions is similar to the treatment of maculopapular rash and lichenoid eruptions, with the addition of rituximab in grade 3-4 rash. Skin hypopigmentation/depigmentation does not require specific dermatologic treatment aside from photoprotective measures. In addition to topical corticosteroids, psoriasiform rash may be managed with vitamin D₃ analogues, narrowband ultraviolet B light phototherapy, retinoids, or immunomodulatory biologic agents. Stevens-Johnson syndrome and other severe cutaneous immune-related adverse events, although rare, have also been associated with checkpoint blockade and require inpatient care as well as urgent dermatology consultation.

Medication-related osteonecrosis of the jaw related to epacadostat and pembrolizumab

MRONJ is a well-known side effect of various medications, such as antiresorptive drugs, anti-angiogenic agents, immunomodulators and immunosuppressants. MRONJ related to immunotherapy is rarely described, with only one case related to ipilimumab. The interaction between the immune system and osteoclast lineage cells is well known. T cells release factors and cytokines that control osteoclastogenesis, and osteoclasts produce factors with an action on T cells. We attempted to explain how immunotherapy could cause MRONJ through the case report of a young patient with metastatic melanoma who developed maxilla MRONJ after pembrolizumab and epacadostat treatment.

Pharmacological modulation of radiation-induced oral mucosal complications

Radiation-induced mucositis is a common toxicity, especially in patients with head and neck cancers. Despite recent technological advances in radiation therapy, such as intensity-modulated radiotherapy, radiation-induced mucositis is still causing treatment disruptions, negatively affecting patients' long and short term quality of life, and impacting medical resources use with economic consequences. The objective of this article was to review the latest updates in the management of radiation-induced mucositis, with a focus on pharmaceutical strategies for the prevention or treatment of mucositis. Although numerous studies analysing the prevention and management of oral radiation-induced mucositis have been conducted, there are still few reliable data to guide daily clinical practice. Furthermore, most of the tested drugs have shown no (anti-inflammatory cytokine, growth factors) or limited (palifermin) effect. Therapies for acute oral mucositis are predominantly focused on improving oral hygiene and providing symptoms control. Although low-level laser therapy proved efficient in preventing radiation-induced oral mucositis in patients with head and neck cancer, this intervention requires equipment and trained medical staff, and is therefore insufficiently developed in clinical routine. New effective pharmacological agents able to prevent or reverse radio-induced mucositis are required.

Immune Toxicity with Checkpoint Inhibition for Metastatic Melanoma: Case Series and Clinical Management

Immune checkpoint inhibitors (anti-PD-1 and anti-CTLA-4 antibodies) are a standard of care for advanced melanoma. Novel toxicities comprise immune-related adverse events (irAE). With increasing use, irAE require recognition, practical management strategies, and multidisciplinary care. We retrospectively evaluated the incidence, kinetics, and management of irAE in 41 patients receiving anti-PD-1 antibody therapy (pembrolizumab) for advanced melanoma. 63% received prior anti-CTLA-4 antibody therapy (ipilimumab). IrAE occurred in 54%, most commonly dermatological (24%), rheumatological (22%), and thyroid dysfunction (12%). Thyroiditis was characterised by a brief asymptomatic hyperthyroid phase followed by a symptomatic hypothyroid phase requiring thyroxine replacement. Transplant rejection doses of methylprednisolone were necessary to manage refractory hepatotoxicity. A bullous pemphigoid-like skin reaction with refractory pruritus responded to corticosteroids and neuropathic analgesia. Disabling grade 3-4 oligoarthritis required sulfasalazine therapy in combination with steroids. The median interval between the last dose of anti-CTLA-4 antibody and the first dose of anti-PD-1 therapy was 2.0 months (range: 0.4 to 22.4). Toxicities may occur late; this requires vigilance and multidisciplinary management which may allow effective anticancer therapy to continue. Management algorithms for thyroiditis, hypophysitis, arthralgia/arthritis, colitis, steroid-refractory hepatitis, and skin toxicity are discussed.

Oral and Dental Health in Head and Neck Cancer Patients

A diagnosis of head and neck cancer (HNC) is typically followed by therapy that is associated with immediate and long-lasting toxic consequences. HNC patients' oral health needs may be complex and are best addressed in multidisciplinary collaborative teams including surgical, medical, and radiation oncologists, dental providers, nutrition, speech/swallow specialists, and physical therapists. Oral health maintenance also requires patient compliance and caregiver support. The role of dental providers begins prior to cancer diagnosis and continues through survivorship. This includes oral screening and health maintenance, management of common oral complications such as mucositis, pain, infection, salivary dysfunction, altered taste, and dental decay, as well as complex issues that include soft tissue fibrosis, osteoradionecrosis of the jaw, dysphagia, and recurrent/new primary malignancies. As the number of potential therapeutic interventions for HNC increase, so do the spectrum of side effects affecting the oral cavity, oropharynx, and dentition. Specific approaches to oral care must be tailored to the idiosyncrasies of the patient and his/her therapy and condition. Oral and dental care is impacted by the patient's oral and dental status prior to cancer therapy, as well as the specific cancer type, location, stage, and its treatment and potential comorbid conditions. Communication between the dental professional and the oncology team is required for appropriate therapy and is best accomplished by integrated healthcare teams.

Common oral complications of head and neck cancer radiation therapy: mucositis, infections, saliva change, fibrosis, sensory dysfunctions, dental caries, periodontal disease, and osteoradionecrosis

Patients undergoing radiation therapy for the head and neck are susceptible to a significant and often abrupt deterioration in their oral health. The oral morbidities of radiation therapy include but are not limited to an increased susceptibility to dental caries and periodontal disease. They also include profound and often permanent functional and sensory changes involving the oral soft tissue. These changes range from oral mucositis experienced during and soon after treatment, mucosal opportunistic infections, neurosensory disorders, and tissue fibrosis. Many of the oral soft tissue changes following radiation therapy are difficult challenges to the patients and their caregivers and require life-long strategies to alleviate their deleterious effect on basic life functions and on the quality of life. We discuss the presentation, prognosis, and management strategies of the dental structure and oral soft tissue morbidities resulting from the administration of therapeutic radiation in head and neck patient. A case for a collaborative and integrated multidisciplinary approach to the management of these patients is made, with specific recommendation to include knowledgeable and experienced oral health care professionals in the treatment team.

Dermatologic complications of anti-PD-1/PD-L1 immune checkpoint antibodies

PURPOSE OF REVIEW

The therapeutic use of anti-PD-1/PD-L1 antibodies (nivolumab, pembrolizumab) is rapidly increasing. Given their mechanism of action that triggers T-cell activation, these immune checkpoint inhibitors induce specific adverse events that are mostly of immunologic origin. In this way, cutaneous toxicities represent the most frequent immune-related adverse events (irAEs). The purpose of this review is to summarize the most prevalent dermatologic complications induced by PD-1/PD-L1 immune checkpoint-blocking antibodies and to compare their dermatologic safety profile with anti-CTLA-4 ipilimumab.

RECENT FINDINGS

More than 40% of melanoma patients treated with anti-PD-1 therapy are faced with dermatologic irAEs. However, these cutaneous complications usually remain self-limiting and readily manageable. Nonspecific macular papular rash and pruritus represent the most common manifestations. More characteristic lichenoid dermatitis or psoriasis may also develop. Vitiligo is also frequent in patients with melanoma but has not been reported in other types of solid cancers. Mucosal involvement may also occur, including xerostomia and lichenoid reactions. Although available data remain scarce, anti-PD-L1 antibodies present a similar dermatologic safety profile.

SUMMARY

Dermatologic irAEs induced by PD-1 or PD-L1 blockade therapy rarely result in significant morbidity or permanent discontinuation of treatment. However, early recognition and appropriate management are crucial for restricting dose-limiting toxicities.

Supportive care for patients undergoing immunotherapy

Immune checkpoint inhibitors, a new class of cancer therapeutic agents, play an important role in the management of melanoma, NSCLC, and other malignancies. A workshop organized by three MASCC Study Groups: Oral Care, Skin Toxicities, and Neutropenia, Infection, and Myelosuppression during the MASCC Annual Meeting held in Adelaide, Australia on 23-25 June, 2016 focused on the new class of anti-cancer therapeutic agents. Topics in the workshop included the mechanism of action and clinical uses of immune anti-CTL4 and anti-PD1 antibodies, checkpoint inhibitor toxicities, including skin adverse events, gastrointestinal toxicities, oral complications, pulmonary toxicities, and endocrinological and immune-related infections. Checkpoint inhibitors have been approved for use in different malignancies including metastatic melanoma, advanced non-small cell lung cancer, metastatic renal cell carcinoma, refractory Hodgkin's lymphoma, metastatic bladder cancer, and advanced head and neck cancer, and the list continues to grow. In general, these agents seem to be better tolerated in most patients and less toxic compared to conventional chemotherapy. However, the toxicities here, termed immune-related adverse events (irAEs), are unique and different from what we have seen in the past. There is no prospective data on these toxicities, and guidelines or recommendations are currently based on symptomatic management from the ongoing clinical trials. Treating oncologists need to be aware and alert themselves to the subtleties in presentation and the big difference in the way we manage the irAEs. Although most irAEs are low-grade and manageable, they have the potential to be life-threatening and extremely severe if not promptly treated. Additionally, irAEs could even lead to death, if managed incorrectly. The MASCC workshop addressed the various irAEs, per organ system, clinical presentation, management recommendations, and individual toxicities.

Oral mucosal changes induced by anticancer targeted therapies and immune checkpoint inhibitors

Development of biological targeted therapies and immune checkpoint inhibitors has redefined the treatment for many cancers; however, the increasing use of new protocols has led to physicians observing a new spectrum of toxicities. To date, oral adverse events induced by these new anticancer therapies have been mainly reported using nonspecific terminology ("stomatitis," "mucosal inflammation," "mucositis") and remain poorly characterized, with the exception of mammalian target of rapamycin (mTOR) inhibitor-associated stomatitis. Oral toxicities of targeted therapies often display very characteristic features which clearly differ from classic oral injuries observed with cytotoxic chemotherapy and/or radiotherapy. In addition, they frequently affect more than 20% of treated patients and can lead to a significant morbidity or permanent treatment discontinuation. Oral mucosal toxicities described in this review include mTOR inhibitor-associated stomatitis (mIAS); stomatitis, benign migratory glossitis, and osteonecrosis of the jaw associated with multi-targeted kinase inhibitors of the VEGF and PDGF receptors; mucositis induced by EGFR inhibitors (in monotherapy or in combination with head and neck radiotherapy and/or chemotherapy); hyperkeratotic lesions with BRAF inhibitors; pigmentary changes and lichenoid reactions secondary to imatinib; and more recent data on the "Osler-Weber-Rendu-like syndrome" described with the antibody-drug conjugate, TDM-1. Finally, we provide, to our knowledge, the first available structured data on oral toxicities induced by the new recently FDA- and EMA-approved monoclonal antibodies targeting PD-1. Clinical management of these targeted therapy-related oral changes is also discussed.

Oral and dental health in head and neck cancer survivors

Therapeutic improvements and epidemiologic changes in head and neck cancer (HNC) over the last three decades have led to increased numbers of survivors, resulting in greater need for continuing management of oral and dental health in this population. Generally, the HNC patient oral health needs are complex, requiring multidisciplinary collaboration among oncologists and dental professionals with special knowledge and training in the field of oral oncology. In this review, we focus on the impact of cancer treatment on oral health, and the oral care protocols recommended prior to, during and after cancer therapy. The management of oral complications such as mucositis, pain, infection, salivary function, taste and dental needs are briefly reviewed. Other complications and their management, including osteonecrosis of the jaw and recurrent/new primary malignancies are also described. This review offers clinical protocols and information for medical providers to assist in understanding oral complications and their management in HNC patients and survivors, and their oral and dental health care needs. Oral and dental care is impacted by the patient's initial oral and dental status, as well as the specific cancer location, type, and its treatment; thus, close communication between the dental professional and the oncology team is required for appropriate therapy.