Update on neurological paraneoplastic syndromes.

PURPOSE OF REVIEW: To provide an update on paraneoplastic neurologic syndromes (PNS), the involved tumors, and types of immune responses.

RECENT FINDINGS: PNS are a diverse group of syndromes that may present as a relatively isolated syndrome such as predominant cerebellar degeneration or limbic encephalitis, or with more complex phenotypes such as diffuse encephalomyelitis that affects different levels of the neuraxis producing a variety of clinical manifestations. The detection of specific antineuronal antibodies can confirm or strongly support the paraneoplastic cause of the syndrome and direct the search for the associated cancer. Previously thought to be unresponsive to therapy, it has recently been shown that there are some antibody-associated PNS that are highly responsive to treatment, including tumor-directed therapies and immunotherapy.

SUMMARY: The recognition of PNS is important for the early detection of an underlying malignancy and prompt initiation of therapies, which offers the best opportunity to stabilize or improve the neurological deficits and for those syndromes associated with cell surface antibodies usually results in substantial improvement or full recovery.