Paraneoplastic Syndromes

Paraneoplastic syndromes are uncommon manifestations of cancer not directly related to mass effect or to a substance normally produced by the cancerous tissue. They may present before or after the diagnosis of cancer. Not all syndromes resolve even with cure or remission of the underlying cancer. Nearly any cancer can cause a paraneoplastic syndrome, though neuroendocrine tumors are most likely. Paraneoplastic syndromes may be classified based on the organ system affected or the pathogenic mechanism. This article uses the former and discusses an array of known endocrine, hematologic, renal, dermatologic, neurologic, and rheumatologic syndromes.