DRESS syndrome is a severe cutaneous drug reaction characterized by fever, lymphadenopathy, hematologic abnormalities, multisystem involvement, and viral reactivation. Reslizumab, a monoclonal anti-interleukin-5 antibody, may be considered in the management of DRESS syndrome. In this study, we report two cases of DRESS syndrome successfully treated with reslizumab. A 30-year-old male, who had been taking allopurinol for a month presented to our clinic with generalized erythematous patches that appeared a week ago. Additionally, a 39-year-old female, who had been taking several medicines, including carbamazepine, was referred to our clinic with erythematous patches on her face, trunk, and extremities appearing 10 days ago. In both cases, based on the history of medication usage and European Registry of Severe Cutaneous Adverse Reactions to Drugs and Collection of Biological Samples criteria, DRESS syndrome was diagnosed. Eosinophilia and systemic symptoms aggravated despite intravenous corticosteroid administration, however, they improved after intravenous reslizumab injection. These cases indicate that DRESS syndrome, which could not be treated with corticosteroids, could be successfully managed with reslizumab.

Angiosarcoma is a rare yet aggressive tumor that originates from endothelial cells lining the blood or lymphatic vessels. Angiosarcoma is commonly associated with radiotherapy, often developing as a secondary cancer following irradiation. In this report, we present a case of a 66-year-old woman who underwent a lumpectomy with adjuvant radiotherapy for left breast cancer 9 years ago. She was referred to our clinic due to erythematous nodules and papules on the left breast that developed 10 months prior. A cutaneous biopsy revealed irregular, anastomosing vessels lined by crowded swollen endothelial cells, exhibiting nuclear atypia. The immunohistochemical stains for alpha-smooth muscle actin and CD31 were positive, while the ki-67 index was elevated. However, the stain was negative for human herpesvirus 8. Clinical and histopathological features were consistent with angiosarcoma associated with adjuvant radiotherapy. The patient underwent a left total mastectomy with sentinel lymph node biopsy. However, 18 months later, multiple bone metastases were noted on positron emission tomography-computed tomography, and the patient received palliative radiotherapy and supportive care.