Abstract: Three patients with reactive capillary hemangiomas caused by PD-1 inhibitor (calerizumab) treated for solid tumorsed are reported and the related literature is reviewed. After the first treatment with calerizumab, the patients with solid tumors gradually developed to capillary hemangiomas. The lesions were red-nevus-like, pearl-like or mulberry-like, and were most on the head and neck, trunk, and extremities. Dermoscopic examination revealed multiple, small, well-demarcated, red lacunae scattered throughout the lesion on a background of red-whitish homogenous color. The diagnosis of reactive capillary hemangiomas was made.

Key words: calerizumab, reactive capillary hemangiomas