Successful Treatment of Sarcomatoid Carcinoma Using Nivolumab Plus Ipilimumab Combination Immunotherapy: a Case Report

. ABSTRACT ━━ Background. Pulmonary pleomorphic carcinoma, a subtype of sarcomatoid carcinoma, is a rare lung malignancy. This cancer is usually resistant to chemo- and radiotherapy, and no standard treatment proto-cols are currently available. We herein report a case of sarcomatoid carcinoma in a patient who responded to combination therapy using nivolumab plus ipilimumab. Case. A 62-year-old man who was a current smoker was re-ferred to our hospital with right lower extremity paresis. Computed tomography revealed a mass in the right upper lung, and magnetic resonance imaging showed multiple brain metastases. Endobronchial ultrasound-guided transbronchial needle aspiration of the mass revealed sarcomatoid carcinoma with a low expression of programmed cell death ligand-1 (PD-L1), and the tumor proportion score was 10%, being classified as clinical stage IVB (cT3N0M1c [BRA]). Following stereotactic radiotherapy to the brain lesions, he was administered combination immunotherapy using nivolumab (360 mg/kg every 3 weeks) and ipilimumab (1 mg/kg every 6 weeks). We observed shrinkage of both lung and brain lesions, which was considered a partial response, and he showed only mild immunotherapy-induced toxicity. Conclusion. Immune checkpoint inhibitors may serve as an effective therapeutic option in patients with sarcomatoid carcinoma; combination therapy using these agents may provide an improved therapeutic benefit in such cases. (