Oral lichenoid drug eruption due to osimertinib for lung cancer.

INTRODUCTION: Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR) are linked with side effects involving skin and mucosa. Herein, we present a unique case of oral lichenoid drug eruption (LDE) in a patient treated with osimertinib. CASE REPORT: A 75-year-old woman was diagnosed with metastatic EGFR-mutated lung adenocarcinoma, and started on osimertinib 80 mg PO daily. At 24 months of therapy, the patient developed a painful, red, and white striated oral lesion involving the left buccal mucosa and the adjacent buccal aspect of gingivae. Biopsy showed oral LDE. Causality assessment between osimertinib and the oral LDE via Naranjo Adverse Drug Reaction probability scale revealed a score of 5. MANAGEMENT AND OUTCOME: Osimetinib discontinuation was not felt to be in the best interest of the patient. Therefore, diphenhydramine HCL mouthwash every 6 h PRN (before meals) was started. Spicy and hot foods were discontinued. At a four-week follow-up visit, the patient reported moderate improvement in her symptoms. CONCLUSION: Oral LDEs are considered premalignant lesions as they can transform into squamous cell carcinoma; therefore, regular follow-up is needed. Awareness of this potential side effect of osimertinib would also prevent unnecessary (and potentially costly) work-up and lead to its prompt diagnosis and treatment.

Sjogren's syndrome due to immune checkpoint inhibitors (ICIs): Insights from a single-institution series and systematic review of the literature.

INTRODUCTION: Careful adverse event assessment and management are important when prescribing immune checkpoint inhibitors (ICIs) to cancer patients. Iatrogenic Sjogren's syndrome is a relatively rare immune-related adverse event (irAEs) that affects the moisture-producing glands. METHODS: We describe a series of four patients who developed Sjogren's syndrome while being treated with ICIs at a community cancer center in Southern California, USA (1/1/2017-12/31/2023). Patient, drug and disease-related data were collected by retrospective chart review. A systematic search of the PubMed database was performed to identify similar cases in the literature (1/1/2016-12/31//2023). RESULTS: Of 224 cancer patients at our center treated with ICIs, four (1.8%) developed iatrogenic Sjogren's syndrome. All of our patients were male; three received PD-1 inhibitors (nivolumab, pembrolizumab) and one received the PD-L1 inhibitor atezolizumab. The median time to development of Sjogren's syndrome was 24 weeks (range, 8-36 weeks); dry mouth symptoms were more prominent than dry eye symptoms. None of the patients had elevated SS-A, SS-B or antinuclear antibodies. One patient developed multiple tooth cavities and had several extractions, due to severe xerostomia. Management of all patients was primarily symptomatic. Two cases were irreversible; one was reversible and the 4th case is undermined as he is still on ICI therapy. Our systematic review of the literature identified 80 cases in five articles. Incidence of xerostomia was twice of that of xerophthalmia. The male/female ratio was 1.5:1. SS-A, SS-B, or antinuclear antibodies were found in only 9% of patients. Steroids were reported to have had only a limited role in management. CONCLUSIONS: The incidence of Sjogren's syndrome due to ICIs in our center was 1.8%. Details of clinical course and management in these patients are presented. Caring for patients with ICI-related Sjogren's syndrome is facilitated by a multidisciplinary effort including oncologists, otolaryngologists, dentists, ophthalmologists and rheumatologists. Expanding the knowledge base pertaining to iatrogenic Sjogren's syndrome in patients on ICIs will be helpful in promoting early detection and treatment, and improving outcomes.

Unusual stroke-like symptoms with oxaliplatin use.

INTRODUCTION: Oxaliplatin has become the mainstay of treatment for many cancers, but its use can be accompanied by unusual side effects. CASE REPORT: We describe herein a 74-year-old patient with pancreatic cancer who developed severe motor weakness affecting lower extremities after starting treatment with oxaliplatin on three separate occasions. Our patient also experienced slurred speech, with decreased ability to phonate and word-finding difficulty. Brain imaging studies did not suggest recent brain ischemia, and the symptoms resolved within 15-20 h. MANAGEMENT AND OUTCOME: Oxaliplatin had to be discontinued due to suboptimal tolerance and a short-lived clinical response. After discontinuation of oxaliplatin, she did not experience any more similar symptoms. A score of 9 on the Naranjo nomogram supported a definite causality relationship between oxaliplatin and the observed neurologic toxicity. DISCUSSION: Rare reports of stroke-like events have previously been described with oxaliplatin. While the exact mechanism of these phenomena is not known, alterations in neuronal sodium channels might be involved. Clinicians, pharmacists, and patients need to be aware of these rare but important side effects of oxaliplatin. Nonetheless, work-up for a cerebrovascular accident is still warranted as hypercoagulability related to malignancy can also predispose the patients to strokes.

Cycle-dependent eosinophilia due to adjuvant nivolumab for malignant melanoma.

INTRODUCTION: Immune checkpoint inhibitors (ICIs) have been widely used in the contemporary anticancer armamentarium. However, new side effects due to these agents have continued to emerge. CASE REPORT: We describe herein a 71-year-old patient who received nivolumab as adjuvant therapy for malignant melanoma of the skin. He developed eosinophilia starting at 4 weeks of therapy. Eosinophilia increased progressively during the first six nivolumab cycles, then stabilized. Cycle-dependent increments were observed. Subsequently, the patient experienced well-known side effects of ICIs such as grade 1 diarrhea, arthralgias, and erythematous papular rash. MANAGEMENT AND OUTCOME: Nivolumab was continued, and absolute eosinophil counts were monitored. Prednisone 10 mg PO daily was required for moderate gastroenteritis, dermatitis, and arthritis, which all subsequently improved. Eosinophil levels gradually downtrended after starting prednisone. Causality assessment between nivolumab and eosinophilia via adverse drug reaction (ADR) probability scale revealed a score of 9. DISCUSSION: Physicians and pharmacists need to be aware of this important side effect of ICI therapy. Eosinophilia in the context of ICI use has been previously reported in clinical trials. Our case is unique as eosinophilia was cumulative, showed increments every 8 weeks, and exhibited a trend toward cycle dependency. Extensive and expensive workup does not appear warranted, and simple monitoring of complete blood count is appropriate in most patients. Further studies are necessary to assess the true incidence, pattern, and severity of eosinophilia related to ICIs as well as its association with clinical outcomes.