Correlation of circulating antineuronal antibodies (CANA) with paraneoplastic syndromes in lung cancer

Paraneoplastic syndromes (PS) are defined as indirect or remote effects of tumors, not caused by metastases [29]. They may be effects of the production of hormones, growth factors, immunologic phenomena or yet unidentified agents [ 1,6]. For some PS the etiology is still obscure, in others the pathomechanism has been elucidated. Endocrine PS like Cushing’s syndrome in small cell lung cancer (SCLC) are best understood from the clinical and biologic point of view [9,21,23]. PS are characterised by different features: Some are typical for certain tumors and may herald an otherwise clinical asymptomatic tumor. PS may be the dominant symptom of the illness. Some PS can be used as a marker for clinical progression or remission during treatment [77,108]. Their exact incidence is not known, possibly due to the incongruous definition of PS. Seven to 15% of tumor patients are estimated to suffer from PS [l]. The incidence is much higher when not universally accepted general symptoms are included. Another problem in the classification of PS is its confusion with direct effects of cancer or effects of therapy. Approximately 200 different PS have been described [103]. For several tumor entities these syndromes need be neither specific nor pathognomonic. Some may even be found in patients without tumors. Almost all known PS have been observed in LC patients, especially in small cell lung cancer (SCLC) [lo 1,103].