Severe Skin Disorders Due to Sorafenib Use After Nivolumab Treatment in Renal Cell Carcinoma Patients.

Background We report two cases in which severe skin disorders developed during sorafenib treatment in patients with renal cell carcinoma (RCC) who had previously received nivolumab. Case report Case 1: A 50-year-old man with RCC received nivolumab as the fifth-line therapy followed by sorafenib as the sixth-line therapy. On day 15 of sorafenib administration, the patient was hospitalized with systemic erythema multiforme, acne-like skin rash, and hand-foot syndrome. Case 2: A 40-year-old man with RCC received nivolumab as the second-line therapy followed by sorafenib as the fifth-line treatment. On day 12 of sorafenib administration, the patient was hospitalized with an acne-like skin rash and hand-foot syndrome. The skin disorders in the two cases improved within 2-3 weeks after sorafenib discontinuation and the start of treatment with topical and oral steroids. Conclusion When using sorafenib in patients previously treated with nivolumab, close attention should be paid to the onset of serious skin disorders.