Incidence rate of metastases in the oral cavity: a review of all metastatic lesions in the oral cavity

Metastases in the oral cavity are rare and account for only 1 to 3% of all malignant lesions in this area. The primary location from which most metastases have been described in the oral cavity in adult patients include lungs, breasts, kidneys and colon. A systematic search of the literature was carried out following the PRISMA statement in PubMed database. Clinical trials and case series published in the last 10 years [2010-2020] were eligible to be selected. The headings and keywords used in the searches were "cancer" AND "oral metastases", "incidence" AND "oral metastases", "oral metastases" AND "jaw bone", "oral metastases" AND "soft tissue". For the study of the incidence of metastases in the oral cavity, 9 reports of clinical trials and 7 retrospective studies of case series have been included in this article. The primary locations from which more metastases have been described in the oral cavity are lungs (30.6% or 183 cases), breasts (22.2% or 133 cases), liver (15.5% or 93 cases), prostate (9 % or 54 cases), thyroid glands (8.1% or 49 cases), kidneys (7.3% or 44 cases), skin (2.3% or 14 cases), soft tissues (2% or 12 cases), colon (2% or 12 cases) and gastrointestinal (0.6% or 4 cases). These metastases have a predilection for hard tissues. The clinical presentation of these lesions varies from painless granulomatous lesions to lytic areas in the jaws. Although metastases in the oral cavity is an uncommon pathology, early diagnosis is needed so that in the event that it is the first manifestation, it allows the primary tumor to be diagnosed as soon as possible.