OBJECTIVETo analyze the clinical features, diagnosis and treatment of lung cancer associated paraneoplastic limbic encephalitis (PLE).

METHODSThe clinical data of 7 cases of patients with lung cancer associated PLE out of 8927 patients of lung cancer from January 2000 to May 2010 was analyzed retrospectively. All the patients were male, aging from 41 to 54 years with a mean of 48 years. The data including history, physical examination, laboratory tests, diagnosis, treatment and follow-up were collected and analyzed.

RESULTSAll the 7 patients had smoking history. All 7 patients had varying short-term memory loss, 6 had epilepsy, 4 had different degrees of mental disorders, and 2 had syndrome of inappropriate secretion of antidiuretic hormone. Malignancies were screened and detected by chest X-ray or CT scan, while the pathological diagnoses were obtained through biopsy or transbronchial needle aspiration through electronic bronchoscope (5/7), biopsy of supraclavicular lymph nodes (1/7) and open pulmonary lobectomy (1/7). The pathological diagnosis included small cell lung cancer in 6 cases, adenocarcinoma of lung in 1 case. During the follow-up, 1 patient was lost, and the mean time of follow-up of the remaining 6 patients was about 11.5 months (ranged from 4 to 21 months). Four patients received early immunosuppressive treatment in terms of corticosteroids, only slight relief of neurological symptoms was seen in 2 patients. However, after chemotherapy (6/6), radiation (3/6), or surgical removal of the tumor (1/6), complete remission (3/6, with negative anti-Hu antibody) or partial remission (3/6, 2 of whom with positive anti-Hu antibody) of neurological symptoms were observed. Till October 2010, 3 patients with poorer tumor stag died ( survival were 4, 10, and 14 months respectively), while the other 3 patients with negative anti-Hu antibody and relative better tumor stag were still in the follow-up (the period were 5, 15, and 21 months).

CONCLUSIONSPLE is a rare disease. In comparison with immunosuppressive therapy, chemotherapy, radiation or surgical removal of the tumor could provide better remission of the neurological symptoms. Positive serum anti-Hu antibody, poorer tumor stag, and together with poorer response to treatments seem to indicate a poorer prognosis.