[CGH findings in neuroendocrine tumours of the lung].

According to the 1999 World Health Organisation classification of lung tumors, the classification of neuroendocrine (NE) tumors is solely based on light-microscopic features. Typical and atypical carcinoid tumors are distinguished from large cell (LCNEC) and small cell neuroendocrine carcinomas (SCLC). We used comparative genomic hybridization (CGH) on 50 samples to investigate the cytogenetic relationships between NE tumors. On average, carcinoid tumors showed markedly fewer chromosomal imbalances (1.8/case, 23 cases) than LCNEC (13.3/case, 17 cases) or SCLC (17/case, 10 cases). The frequency of amplicons increased accordingly. Typical carcinoid tumors exhibited significant defects on chromosomes 11 and 13 only. Interestingly, only the frequency of losses on chromosome arm 11q was very similar for all three tumor entities (about 30%). In conclusion, the CGH results support the classification of typical carcinoid tumors as a separate entity in clear distinction from the NE carcinomas.