The diagnosis of a paraneoplastic syndrome (PNS) may precede, follow or be concurrent with the diagnosis
of a malignant tumor. There is increasing knowledge of association between PNS and head and neck
cancers, but the relationship between oral cancer and paraneoplastic disease has not been previously
investigated. PNS associated with head and neck cancer can be divided into six main groups: endocrine,
cutaneous or dermatologic, hematologic, osteoarticular or rheumatologic, neurologic, and ocular syndromes.
We have comprehensively reviewed the literature to evaluate the incidence of occurrence of
PNS with oral cancer, and conclude that only endocrine and dermatologic PNS have been associated with
oral cancer. Humoral hypercalcemia is the most frequent PNS related to oral cancer, and has a negative
prognostic significance. Dermatologic PNS are less common, but when they occur, they may precede the
diagnosis of the oral tumor. Awareness of these conditions is important for clinicians who deal with
cancer.
