BACKGROUNDTo investigate the clinical characteristics and diagnosis of lung cancer with paraneoplastic syndrome as initial symptom.

METHODSThe clinical data of 168 cases of lung cancer with paraneoplastic syndrome as initial symptom were analysed from Jan. 1990, to Nov. 2002, in the hospital.

RESULTS(1) Among the patients with lung cancer in the hospital, 11.8% (168/1 426) had paraneoplastic syndrome as initial symptom. The ratio of male to female was 4.25:1. There were 138 cases aged above 45 (82.1%) and 116 with smoking history (69.0%). (2)There were 62 cases of small cell lung cancer (36.9%) and 102 non small cell lung cancer (60.7%) and 4 carcinoid (2.4%). Thirty-three cases (37.5%) were central type and 82 (48.8%) peripheral type and 23 (13.7%) diffuse type. (3) The patients with paraneoplastic syndrome included: 48 cases of osteoarthopathy (28.6%), 27 cachexia (16.1%), 23 cancerous fever (13.7%), 14 myasthenia (8.3%), 12 vegetative nerve hyperfunction (7.1%), 11 cerebellar cortex degeneration (6.5%), 9 acanthosis nigricans (5.4%), 8 cutaneous pigmentation (4.8%), 7 dermatomyositis (4.2%), 5 encephalopathy (3.0%), and 4 gynecomastia (2.4%). (4)The misdiagnosis rate of the first consultation was 44.6% (75/168). (5)Initial chest X-ray positive rate was 61.9% (104/168); initial CT positive rate was 78.6% (132/168). (6)One hundred and thirty-two cases accepted the treatment of lung cancer: 32 cases accepted pure operation, 8 cases accepted pure chemotherapy, 35 cases accepted operation and chemotherapy, 39 cases accepted chemotherapy and radiotherapy, 18 cases accepted operation and chemotherapy and radiotherapy. Totally 8 cases were dead and 17 cases had abandoned treatment. One hundred and seven cases had improvement after complex treatment of lung cancer, including 83 cases with improvement or disappearance of paraneoplastic syndrome, 18 cases with no change, and 6 cases exacerbated.

CONCLUSIONSThe lung cancer with paraneoplastic syndrome as initial symptom is difficult to diagnose because of its latent onset. The knowledge of paraneoplastic syndrome should be improved, chst X-ray or CT examination should be done for the high risk group of lung cancer with paraneoplastic syndrome, and these strategies could decrease misdiagnosis rate and increase diagnosis rate of lung cancer in early stage.