Paraneoplastic syndromes in patients with primary head and neck cancer.

Paraneoplastic syndromes represent the clinical manifestations of the indirect and remote effects produced by tumor metabolites or other products. The clinical spectrum of the various paraneoplastic syndromes related to primary malignancies of the head and neck region is presented. A review of the literature on paraneoplastic syndromes in patients with primary head and neck cancer was carried out. Paraneoplastic syndromes related to primary malignancies of the head and neck region can be categorized as: endocrine, cutaneous or dermatologic, hematologic, neurologic, osteoarticular or rheumatologic, ocular syndromes. Sometimes, paraneoplastic syndromes can be more serious than the consequences of the primary tumor itself and can precede, follow or be concurrent to the diagnosis of a malignancy; moreover, they can dominate the clinical picture and thus lead to errors with respect to the origin and type of the primary tumor. Physicians who deal with cancer-associated syndromes should be able to differentiate the paraneoplastic syndromes from the benign disorders that mimic them. Patients with a suspected paraneoplastic disorder should undergo a complete panel of laboratory studies, in addition to imaging studies and endoscopy. Identification of paraneoplastic syndromes allow the clinician to make an early diagnosis and to provide adequate treatment of tumors, with a favorable oncologic outcome and improved life expectancy for the patient. These syndromes can follow the clinical course of the tumor and thus be useful for monitoring its evolution.