Trousseau syndrome is a neurological disorder caused by blood hypercoagulability due to a malignant tumor and thrombosis in the brain. We report a case of Trousseau syndrome in a 30-year-old female [adolescent and young adult (AYA) classification] with lung and thoracic vertebrae metastases from tongue cancer that developed during pharmacotherapy. In July 2015, squamous cell carcinoma (T1N0M0, Stage I) was diagnosed and the patient underwent a partial right-side tongue resection. In March 2020, combination therapy with paclitaxel and cetuximab was started. After three weeks, dizziness, nausea and vomiting symptoms appeared and cerebellar infarction was confirmed by MRI results, leading to a diagnosis of Trousseau syndrome. Anticoagulant therapy was started, and combination therapy with paclitaxel and cetuximab was resumed after the symptoms improved. Six months later, her general condition deteriorated, and the patient chose best supportive care. Death due to hemorrhage from lung metastasis occurred approximately three months after stopping pharmacotherapy.

SAPHO syndrome is a disorder characterized by aseptic inflammatory bone, joint and skin lesions. Bone lesions in the maxillofacial region often occur in the mandible as diffuse sclerosing osteomyelitis (DSO). It is rarely associated with temporomandibular joint (TMJ) ankylosis. We report an exceptionally rare case of SAPHO syndrome with TMJ ankylosis treated with arthroplasty. The patient was a 50-year-old man with a history of SAPHO syndrome. He was referred to our department in April 2009 due to pain in the left mandible with trismus. His mouth opening was 9 mm. The patient was diagnosed with left mandibular osteomyelitis and started treatment with NSAIDs, but he soon stopped visiting our hospital. He visited the hospital again in November 2013. His mouth opening was 5 mm. Computed tomography showed that the left mandibular condyle had bony adhesions to the glenoid fossa and we diagnosed TMJ ankylosis. Since he also had sternoclavicular joint pain, treatment for SAPHO syndrome was performed in our hospital’s department of collagen disease. The pain soon disappeared, but the mouth opening decreased further to 2 mm, so arthroplasty was performed in May 2017. The mouth opening was 30 mm after the operation. Two years passed after the operation, and the mouth opening was 22 mm. Careful observation is necessary for SAPHO syndrome with DSO, taking the development of TMJ ankylosis into consideration. In severe cases, it is necessary to consider surgical treatment.

Epidermolysis bullosa acquisita is an autoimmune blistering disease in which the type VII collagen of the epidermis basement membrane is the antigen. We encountered a case of epidermolysis bullosa acquisita with initial symptoms on the oral mucosa. The case involved an 82-year-old man referred to our hospital for diagnosis of oral blisters. We diagnosed epidermolysis bullosa acquisita using immunoserology. Symptoms improved after administration of a steroid and colchicine. At eight months after the start of treatment, the patient continued to take prednisolone (10 mg/day) and colchicine (1.0 mg/day) without worsening of oral symptoms that would have impaired quality of life. Extensive blistering in the oral mucosa is highly likely to cause poor pain control and decreased oral intake, and the role of oral hygiene management and symptomatic treatment is very important.

Pembrolizumab is known to cause specific immune-related adverse events (irAE), and myocarditis is a rare but serious irAE. For head and neck cancer, there has been only one case in the KEYNOTE-048 trial pembrolizumab combination group, with no detailed report. We report a case of myocarditis as a pembrolizumab irAE in a patient with late cervical lymph node metastasis from tongue cancer. A 90-year-old man underwent a partial glossectomy (excisional biopsy) in July 2019 following a diagnosis of right-sided tongue cancer, and histopathological diagnosis confirmed a well-differentiated squamous cell carcinoma. Imaging studies performed in January 2020 revealed metastatic lymphadenopathy of the right cervical level IIA nodes. Pembrolizumab therapy was initiated in February 2020 due to the patient’s refusal of the recommended surgery. Although the patient did not initially experience any adverse events, he developed generalized muscle weakness 21 days after administration of the second dose. Blood test results, electrocardiography and coronary artery computed tomography revealed irAE-related myocarditis. He underwent long-term prednisolone therapy for myocarditis. Although his creatine kinase and troponin T levels decreased with electrocardiographic evidence of the gradual resolution of the myocarditis, the patient’s daily life activity significantly declined during hospitalization. He was subsequently transferred to a long-term care hospital for best supportive care.

　In administering ICIs, it was considered extremely important to share knowledge on the management of irAE and to establish medical collaboration systems for early detection and treatment.

Glossopharyngeal neuralgia (GN) is a rare painful condition characterized by brief paroxysmal attacks in the glossopharyngeal nerve distribution. It is triggered by chewing, coughing, talking and swallowing. We report a rare case of combined trigeminal neuralgia and GN triggered by taste stimulation. A 63-year-old man was referred to our hospital with a complaint of sharp left mandibular and submandibular pain caused only by eating sour or salty foods. Computed tomography and sialography revealed a slight salivation disorder but no salivary gland disease. The symptom was not improved by salivary gland massage, and we then examined each pain area using the selective anesthesia test. As the symptoms were improved by topical anesthesia to the tongue root region, we made a diagnosis of GN. Furthermore, magnetic resonance imaging and angiography revealed compressions of the left glossopharyngeal nerve and left trigeminal nerve by the left anterior inferior cerebellar artery and left anterior superior cerebellar artery, respectively, based on which we diagnosed a combination of trigeminal neuralgia and GN. Treatment with carbamazepine relieved the pain favorably; however, the medication was discontinued due to drug eruption. Finally, we performed microvascular decompression for both nerves, after which the patient immediately experienced complete pain relief.