Hypopharyngeal Carcinoma With Synchronous and Metachronous Multiple Malignancies: Clinical Characteristics and Prognosis Analysis of 673 Real World Cases

Approximately 30% of patients with HPC develop multiple malignancies during the course of disease and the most frequently involved site is the upper aero digestive tract. We should be aware of the possible coexistence of SPMs in HPC. Co-existence of gastric/esophageal tumor in situ does not affect outcome. The OS and DSS for synchronous SPMs are significantly worse than that for metachronous SPMs and no-SPMs. The SPMs in esophagus is the most common site and present the worst outcome than others.