Paraneoplastic syndromes: what we know and what we should know.

Paraneoplastic syndromes are a group of clinical disorders associated with malignant diseases that are not directly related to the physical effects of primary or metastatic tumor. Those that are associated with the secretion of circulating peptides may be used as a useful tool in monitoring patients after the start of chemotherapy. Most of the paraneoplastic syndromes represent an interesting tool of internal medicine. Moreover, they also represent a starting point for a work up in patients with an occult neoplasia, even though the clinical presentation may be very multifaceted. As consequence of all these considerations, the present editorial represents a useful tool for a rational approach to paraneoplastic syndromes.