title: The problem of multiple primary tumors in patients with oral malignant disease.
mesh_terms: D006801:Humans; D009062:Mouth Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000276:immunology / Q000473:pathology / Q000628:therapy; D009378:Neoplasms, Multiple Primary / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000276:immunology / Q000473:pathology / Q000628:therapy; D012907:Smoking / Q000150:complications; D013997:Time Factors