Survival of second and multiple primary tumors in patients with oral cavity squamous cell carcinoma in the betel quid chewing area

We report the incidence, risk factor(s), and overall survival (OS) of second/multiple primary tumors (SPTs/MPTs) in oral cavity squamous cell carcinoma (OSCC) patients in betel quid chewing areas. Of 816 untreated OSCC patients who had radical surgery, 15.7% had either synchronous or metachronous SPTs. The SPTs (70.3%) were at the oral cavity. SPTs (18.8%) developed third primary tumors, with a significantly higher incidence in synchromous than metachronous SPTs (p = 0.001). An optimal, but significantly lower, 5-year OS was observed in patients with SPTs/MPTs than without (54.0% vs. 67.2%, p = 0.0195). By multivariate analyses, OSCC sub-sites (p = 0.006) and lymphatic permeation (p = 0.040) were independent risk factors for SPT rate. A significantly higher 5-year OS was observed in SPT patients receiving a second radical surgery at the oral cavity/soft palate than patients that did not (p = 0.0001). A good survival rate can be obtained for OSCC patients with resectable SPTs/MPTs.