Abstract
We analyzed 155 patients with oral cancer (OC) and 118 with oropharyngeal cancer (OPC) treated at our hospital from 1998 to 2010, and studied their clinical features in cases of multiple primary cancer (MPC). There were 30 MPCs (19.3%), including 6 synchronous cases and 24 metachronous cases, among the OC patients and 42 MPCs (35.6%), including 18 synchronous and 24 metachronous cases, among the patients with OPC. The most common sites for MPC development in the OC cases were the stomach, followed by the esophagus, and hypopharynx, and in the OPC cases, the esophagus, followed by the stomach, and lung. The most common subsites for the development of MPCs among oral and oropharynx cases were the tongue and tonsils, respectively.
The prognosis of MPCs was poor in patients with OC and OPC. Patients with synchronous MPC had a significantly worse prognosis than those with OC alone. Synchronous MPC patients were associated with a significantly worse prognosis than metachronous patients with preceding OPC. As for the reasons for the poor prognosis, synchronous patients had an advanced stage in OC cases, and had undesirable results from chemoradiation therapy in OPC cases.
