Camrelizumab in Combination With Apatinib and Temozolomide as First-line Treatment in Advanced Acral Melanoma

Inclusion Criteria: * age:≥18 years, male or female. * Histopathologically confirmed recurrence, inoperable resection or metastatic acral melanoma (stage III/IV). * Has not received any systematic anti-tumor drug treatment. * Measurable disease based on Response Evaluation Criteria In Solid Tumors (RECIST) 1.1. * ECOG 0-1. * Adequate organ function. * Life expectancy of greater than 12 weeks. * Patient has given written informed consent. Exclusion Criteria: * Patients who have or are currently undergoing additional chemotherapy, radiation therapy, targeted therapy or immunotherapy. * Known history of hypersensitivity to macromolecular protein preparation or any components of the drug formulation. * Subjects before or at the same time with other malignant tumors (except which has cured skin basal cell carcinoma and cervical carcinoma in situ); * Subjects with any active autoimmune disease or history of autoimmune disease Uncontrolled clinically significant heart disease, including but not limited to the following: (1) \> NYHA II congestive heart failure; (2) unstable angina, (3) myocardial infarction within the past 1 year; (4) clinically significant supraventricular arrhythmia or ventricular arrhythmia requirement for treatment or intervention; * Received a live vaccine within 4 weeks before the first dose of study medication. * Pregnancy or breast feeding. * Decision of unsuitableness by principal investigator or physician-in charge.