[Synchronous carcinoma of the floor of mouth carcinoma with esophageal carcinoma: a case report].

This study presents a case of synchronous multiple primary cancers involving floor of mouth carcinoma with esophageal carcinoma. Literature was reviewed to summarize the incidence, location, diagnosis, treatment characteristics, and prognosis to improve understanding and awareness of the multiple primary cancer. As a result, early discovery, early diagnosis, and effective treatment can help prolong survival and improve the quality of life of patients.