‘Head and neck cancer’ is a general term for malignant neoplasms arising from subsites of the head and neck area and consists of various histology. Among them, recurrent or metastatic squamous cell carcinoma from the oral cavity, oropharynx, hypopharynx, or larynx (RM-HNSCC) is a primary target of the drug development, the evidence for RM-HNSCC has been adopted for the chemotherapy of oral cancer. Currently, an immune checkpoint inhibitor (ICI) is the main drug for the chemotherapy for RM-HNSCC; the treatment should be performed after fully understanding the difference of the evidence in ‘platinum-sensitive’ or ‘platinum-refractory’ disease. Notably, managing immune-related adverse events (irAE) is essential in ICI therapy because delayed treatment for irAE can lead to fatal events. The physicians in charge must understand the irAE management deeply and distinguish irAE between what should be treated by oneself and what should be consulted with specialists.

Sebaceous carcinoma is a malignant tumor derived from the sebaceous glands. The most common location is in the eyelid sebaceous glands, and this is categorized into occurring either outside or inside the eyelid. Among those that occur outside the eyelid, most originate in the skin. Although there are some reports of o ccurrence in the salivary glands and mammary glands, it is extremely rare in the maxilla. We describe a case of maxillary sebaceous carcinoma. A 68-year-old man was admitted to our hospital with the chief complaint of a gingival mass in the right maxilla. A tumor was palpated under the oral vestibule of the right maxilla, and CT confirmed a protruding mass in the maxilla. A biopsy was performed and a diagnosis of sebaceous carcinoma was made. The patient was referred to the relevant departments for examination of the primary lesion, and a PET scan was also performed, however no other lesions were identified. Resection is recommended for sebaceous carcinoma, therefore a total maxillary resection, supraomohyoid neck dissection and rectus abdominis myocutaneous flap reconstruction were performed. Two years have passed since the operation and no recurrence or metastasis has occurred.

We report a case of Erdheim-Chester disease diagnosed as a result of ulceration of the palate. The patient was a 62-year-old male with the chief complaint of contact pain of the palatal mucosa. He had a beaded mass on the adductor muscle of the right thigh, which was being treated by an orthopedic surgeon. At the same time, an ulcerative lesion was found on the palate. He was referred to the Department of Oral and Maxillofacial Surgery and treated with a steroid ointment. However, the lesion did not improve and a biopsy was performed two weeks later. The biopathologic finding was similar to that of the soft tissue tumor of the leg, and finally a diagnosis of Erdheim-Chester disease was made. The oral lesions did not improve and the contact pain persisted, so protection of the ulcerated surface was performed with indomethacin spray and a 0.5mm celluloid splint. The contact pain was alleviated and feeding improved. However, although chemotherapy was performed for the tumors in both legs, the treatment was discontinued and palliative care was initiated since his general condition worsened due to the exacerbation of the primary disease, hepatocellular carcinoma.