A tissue mass in the floor of the mouth was found to be an unusual, exophytic squamous cell carcinoma. The patient also had synchronous hepatic metastasis from an occult primary adenocarcinoma. The case is discussed from the standpoint of the differential diagnosis of lesions that may appear as masses of the floor of the mouth. Individuals with one primary cancer are at increased risk for developing second malignancies which may be in either the same anatomic area or in other organ systems. This case report emphasizes the need for the clinician to periodically follow-up any patient with a history of malignancy.