Difficulties in the diagnosis and treatment of axillary malignant triton tumors: A case report.

Malignant triton tumor (MTT), a subtype of malignant peripheral nerve sheath tumor, is a rare soft-tissue sarcoma with a difficult diagnosis and poor prognosis. The course of MTT progression is rapid and the degree of malignancy is high. Patients with MTT can be treated with postoperative adjuvant radiotherapy and chemotherapy; however, treatment results are still poor. The present study describes a case of MTT of the axilla, which was diagnosed using histopathology with immunohistochemical staining and gene mutation detection. Complete surgical excision of the left axillary mass was performed in September 2023. Postoperative therapeutics included radiation therapy and deep hyperthermia; nine-field intensity-modulated radiation was delivered to the left axilla (46 Gy in 23 fractions over 5 weeks) and concurrent deep hyperthermia was performed three times per week for 5 weeks. In February 2024, the patient received oral anlotinib at a dose of 10 mg daily (before breakfast) for 2 weeks. It was demonstrated that a combination of surgery, radiation therapy, deep hyperthermia and targeted therapy may improve the survival of patients with MTT. After 1 month of comprehensive treatment, the patient's tumor had disappeared upon reexamination. As of the latest follow-up in October 2024, the patient had achieved a disease-free survival period of ~7 months, the patient was stable and remained on anlotinib treatment with good tolerance. With no standardized treatment recommendations available, the present study demonstrated that the combination of surgery, radiation therapy, deep hyperthermia and targeted therapy may provide a new strategy for the clinical treatment of MTT.