Several aspects of our patient's case were atypical for CCS, including the patient's young age (18 years), tumor location (right upper extremity), histological feature (mass with central cystic hemorrhagic change), and immunohistochemistry profile (pankeratin+, AE1/AE3+, S100+, HMB45−, MelanA−). Here, SLC4A1 is linked to neoplasm.