Real World Study of Diagnosis and First-line Treatment Among Patients With Cancer of Unknown Primary in China

Inclusion Criteria: * Had a diagnosis of cancer of unknown primary (CUP) after a standard evaluation . * Prepared to receive first-line therapy for CUP Exclusion Criteria: * Patients who had previously received systemic therapy for CUP * Previous history of other cancers, except cervix cancer or basal cell carcinoma of the skin that has been cured * The investigator considered that there were contraindications to treatment or were not appropriate to participate in this study