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