Mucosal pigmentation of the hard palate in a patient taking imatinib

Oral Adverse Events Associated with BRAF and MEK Inhibitors in Melanoma Treatment: A Narrative Literature Review

BACKGROUND

Melanoma cancer represents the most lethal type of skin cancer originating from the malignant transformation of melanocyte cells. Almost 50% of melanomas show the activation of BRAF mutations. The identification and characterization of BRAF mutations led to the development of specific drugs that radically changed the therapeutic approach to melanoma.

METHODS

We conducted a narrative review of the literature according to a written protocol before conducting the study. This article is based on previously conducted studies. We identified articles by searching electronic databases (Medline, Google Scholar and PubMed). We used a combination of "melanoma", "Braf-Mek inhibitors", " targeted therapy" and "oral side effects".

RESULTS

Eighteen studies were reported in this article showing the relationship between the use of targeted therapy in melanoma cancer and the development of oral side effects, such as mucositis, hyperkeratosis and cellular proliferation.

CONCLUSION

Targeted therapy plays an important role in the treatment of melanoma cancer, showing a notable increase in response rate, prolonged progression-free survival and overall survival in BRAF-mutated melanoma patients. Oral side effects represent a common finding over the course of treatment. However, these adverse effects can be easily managed in a multidisciplinary approach involving collaboration between medical oncologists and dental doctors.

Oral Manifestations in Melanoma Patients Treated with Target or Immunomodulatory Therapies

BACKGROUND

BRAF (v-raf murine sarcoma viral oncogene homolog B1) and MEK (mitogen activated protein kinase) inhibitors, as well as immunotherapy against cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and the programmed cell death 1 (PD-1) receptor and its ligand (PD-L1), have shown good results in improving the disease-free survival of patients with metastatic melanoma (MM). The aim of this review is to summarize the main oral adverse events (oAEs) occurring in patients undergoing target or immunotherapy. We proposed two separate sections: oAEs during the treatment with (1) target therapies with BRAF and MEK inhibitors and tyrosine kinase inhibitors (gingival hyperplasia, pigmentation disorders, squamo-proliferative lesions) and (2) immunotherapies with CTLA-4 or PD1 inhibitors (lichenoid reactions, immuno-bullous reactions, xerostomia and other reactions). Adverse events frequently include oAEs, although these are often misdiagnosed and under-reported. Indeed, the oral cavity is not routinely evaluated during clinical practice. The symptomatology related to oAEs is significant since it may represent the first manifestation of a severe systemic reaction, possibly leading to difficulties in nutrition with a consequent impact on patients' quality of life. A careful examination of the oral cavity is recommended during the evaluation of oncologic patients in order to promptly detect the onset of new manifestations.

Medication-Induced Oral Hyperpigmentation: A Systematic Review

BACKGROUND

Medication-induced oral hyperpigmentation is an oral condition that impacts patients' quality of life and has been linked to many systemic therapeutic agents. The exact pathogenesis of tissue pigmentation varies greatly and is not completely known. This systematic review aimed to present data on the causal association between medications and the development of oral/mucosal pigmentation as an adverse drug reaction.

METHODS

A systematic review and analysis of literature were conducted using the following databases: PubMed, Science Direct, ProQuest, Web of Science, and Scopus. The systematic review included original articles written in English and published between January 1982 and June 2020. Following the PRISMA statement, eligible articles were systematically reviewed, and data were extracted from eligible studies and analyzed.

RESULTS

A total of 235 articles were identified, of which 57 met the inclusion criteria and were included in this review. The mean age of included patients was 46.2±16.38 years (range: 10-90 years) with a male to female ratio of 1:1.45. Oral mucosal hyperpigmentation was reported following the use of several classes of medications such as antiviral (eg, zidovudine), antibiotic (eg, minocycline), antimalarial (eg, chloroquine), anti-fungal (eg, ketoconazole), antileprotic (eg, clofazimine), antihypertensive (eg, amlodipine), chemotherapeutic, and antineoplastic drugs. The risk of developing oral pigmentation was significantly higher with antimalarial medications, antibiotics, antineoplastic and chemotherapeutic agents. Medication-induced oral hyperpigmentation was most frequent among women and in the hard palate.

CONCLUSION

Future research is warranted to better understand the pathogenesis and risk factors for medication-induced oral hyperpigmentation in order to reassure patients during prescription and management.

Hyperpigmentation due to imatinib: A rare case of cutaneous involvement

Case report

Imatinib mesylate is a well-known tyrosine kinase inhibitor used to treat chronic myeloid leukemia, gastrointestinal stromal tumor, as well as a variety of other malignancies. Management and outcome: As use of this medication continues to grow, providers must be aware of potential side effects and management thereof. The toxicity profile of imatinib has been well characterized with most patients experiencing a grade 1 or 2 adverse event. These side effects are usually mild, and most patients can continue treatment without interruption. Around 30% of patients on imatinib experience skin toxicity, with 5% being high grade. This rash is typically hypopigmented, which is explained by imatinib’s effect on melanocytes.

Discussion

Although there have been several case reports describing hyperpigmentation of the oral mucosa or nails, very few have described skin hyperpigmentation. We previously reported the first two cases of imatinib-related squamous cell carcinoma in patients undergoing treatment for gastrointestinal stromal tumors. In this paper, we present a case of a patient on imatinib for management of gastrointestinal stromal tumor who experienced extensive skin hyperpigmentation and review the literature.

Targeted cancer therapies: Oral health care implications

BACKGROUND

Targeted treatments have been incorporated into oncology protocols, often with more traditional therapies, and are not totally free of adverse reactions, some of which affect the orofacial region.

METHODS

The authors searched PubMed, the Cochrane Library, and the US Food and Drug Administration Approved Drug Products database to identify reported adverse effects of targeted agents in the orofacial region as well as other implications in oral health care. Their principal focus was the relatively newer category of molecularly targeted drugs which are called small molecules (SMs).

RESULTS

The authors identified several categories of SMs and biological agents (for example, monoclonal antibodies) with adverse effects in the orofacial region. The oral and perioral regions are also fields for which there are therapeutic applications for targeted therapies, particularly to treat malignant neoplasms such as head and neck cancers.

CONCLUSIONS

SMs are the most rapidly growing group of targeted cancer treatments. Patients receiving SMs and other targeted antineoplastic agents may require oral medicine advice and special-care dentistry.

PRACTICAL IMPLICATIONS

In this narrative review, the authors focus mainly on the orofacial adverse effects of targeted cancer therapies and outline many of the agents that are in use so the dentally focused reader can familiarize themselves with these adverse effects and agents.

Association of oral mucosa hyperpigmentation with imatinib mesylate use: a cross-sectional study and a systematic literature review

OBJECTIVES

To assess the association between oral mucosa hyperpigmentation in patients with leukemia and imatinib mesylate use. Additionally, we compared our data to those obtained from a systematic review.

MATERIALS AND METHODS

A cross-sectional study was conducted with 74 patients undergoing treatment with imatinib mesylate. Sociodemographic characteristics, oral mucosa alterations, and medical history were evaluated. Oral hyperpigmentation was scored. The use of imatinib mesylate and hydroxyurea was evaluated. Association between oral hyperpigmentation and imatinib mesylate was assessed. A systematic review was also conducted to retrieve case reports or case series of patients with oral hyperpigmentation associated with imatinib mesylate.

RESULTS

Among the 74 participants, 41 were male (55.4%) and 33 were female (44.6%). Participants' mean age was 49.3 years. Sixty-six (89.2%) patients developed hyperpigmented lesions in the hard palate mucosa. In multivariate analysis, patients who had used imatinib mesylate for > 72 months had a hyperpigmentation score 1.62 times higher than those who had used this medication during a shorter period. Patients who had used hydroxyurea for > 30 days had a hyperpigmentation score 1.43 times higher than those who had used this medication during a shorter period. The systematic review retrieved 20 clinical cases of patients undergoing imatinib mesylate treatment and exhibiting oral hyperpigmentation.

CONCLUSIONS

The development of oral hyperpigmentation is associated with imatinib mesylate use. Hydroxyurea seems to increment such an association.

CLINICAL RELEVANCE

To assist providers in the differential diagnosis of hyperpigmented lesions associated with imatinib mesylate, as well as in the clinical management of such lesions.

An Update on Drug-Induced Pigmentation

Drug-induced pigmentation accounts for up to 20% of all cases of acquired pigmentation. A thorough review of medical history and previous and ongoing medications as well as a complete skin examination can guide diagnosis. Implicated agents include alkylating/cytotoxic agents, analgesics, antiarrhythmics, anticoagulants, antiepileptics, antimalarials, antimicrobials, antiretrovirals, metals, prostaglandin analogs, and psychotropic agents, among others. Confirming true drug associations can be challenging, especially in the setting of delayed onset of pigmentation and coexisting polypharmacy.

Imatinib-induced diffuse hyperpigmentation of the oral mucosa, the skin, and the nails in a patient affected by chronic myeloid leukemia: report of a case and review of the literature

BACKGROUND

Imatinib mesylate is a tyrosine-kinase inhibitor used as the first-line treatment in chronic myeloid leukemia patients, but it is also indicated for other hematological diseases and solid tumors. Imatinib treatment is often associated with hypopigmentation, but only a few cases of hyperpigmentation are described in literature.

METHODS

We are reporting the first case of imatinib-related hyperpigmentation involving the oral mucosa, skin, and nails in a patient affected by chronic myeloid leukemia and treated with imatinib since 2002. A review of all the available literature regarding the imatinib-related hyperpigmentation was performed, and one additional case was analyzed. Due to the possibility of a post-inflammatory hyperpigmentation, all cases of pigmentary changes previously characterized by a rash and/or pruritus in the same body areas were excluded.

RESULTS

Thirty cases of well-documented imatinib-related hyperpigmentation were described in literature. In our case, imatinib therapy was well tolerated for several years, and it led to an excellent hematological and cytogenetic response. However, the patient gradually developed a blue-gray pigmentation that involved the nose, fingernails, toenails, pretibial regions, posterior axillary folds, and hard palate. Other causes of pigmentary changes were excluded, and histopathological examination confirmed the clinical suspicion of imatinib-related hyperpigmentation.

CONCLUSIONS

Hyperpigmentation induced by imatinib is an adverse reaction rarely described in literature. The underlying pathogenetic mechanisms are not yet completely clear, and further studies are necessary to elucidate them. Currently, no treatment is required for this condition, and there is no indication to discontinue imatinib treatment.

Hyperpigmentation of the hard palate mucosa in a patient with chronic myeloid leukaemia taking imatinib

Background

Imatinib mesylate is an inhibitor of the tyrosine kinase Bcr–Abl and a first-line treatment for Philadelphia chromosome-positive chronic myeloid leukaemia (CML). Dermatological side effects include superficial oedema, pustular eruption, lichenoid reactions, erythroderma, and skin rash. Depigmentation of the skin and/or mucosa is uncommon, and hyperpigmentation is rare.

Case presentation

We present the case of a 63-year-old Caucasian male with widespread hyperpigmentation of the hard palate associated with a 9-year history of imatinib therapy to treat CML. He did not complain of any symptoms. Clinical examination did not reveal any abnormal pigmentation of the skin or other region of the oral mucosa. He did not smoke cigarettes or drink alcohol. His medication regimen was a proton pump inhibitor, a beta-blocker, cardioaspirin, atorvastatin, and imatinib 400 mg/day. Histopathologically, melanin and haemosiderin deposits were evident in the lamina propria. The lesion persisted, with no clinical change, through several follow-ups. We reviewed the literature to explore the possible relationship between oral hyperpigmentation and long-term imatinib mesylate treatment.

Conclusions

We diagnosed oral pigmentation associated with imatinib intake based on the medical history and clinical features of the pigmented macules. Oral pigmentation may have a variety of causes, and differential diagnosis requires nodal analysis. Clinicians should be aware of possible oral mucosal hyperpigmentation in patients taking imatinib mesylate. Such pigmentation is benign and no treatment is needed, but surveillance is advisable.