Relevance of loss of heterozigosity in chromosome 3p in non small cell lung carcinoma as prognostic factor

BACKGROUND: Recent advances on carcinogenesis have led to the recognition o f different patterns of behaviour of non-small cell lung cancers appart fro m those guided by the TNM staging system and the histologic subtype, The fr equent genetic loss on chromosome 3p in all kinds of lung carcinoma leads t o the suspect of the presence of a tumor suppresor gene located in that pla ce. The aim of this work was to compare the different clinical features and evolution after treatment of the patients with non small cell lung carcino ma with and without loss of heterozigosity (LOH) on 3p, PATIENTS AND METHOD: Forty-five operated on non-small cell lung cancer pati ents were evaluated. The mean age was 64.4 years and all the patients were male, Seven patients had been previously treated for another epithelial neo plasm. 82.2% of the patients were heavy tobbacco smokers. Most of the tumor s (62.2%) were squamous cell carcinomas. Samples of tumoral and non tumoral lung tissue were immediately frozen after surgery, DNA from the tissue was extracted; then PCR amplification of microsatellites in regions 3p14 and 3 p21 was performed. To determine the LOH in the regions analyzed a polyacryl amide gel electrophoresis was performed. RESULTS: Twenty-five percent of the informative samples for 3p14 and 21.9% for 3p21 showed LOH, There was an statistical relationship between the LOH on 3p14 and the history of tobbacco smoking and the adenocarcinoma histolog ic subtype (p < 0.05). There was a higher number of relapses and a shorter disease-free interval in those patients harboring 3p21 LOH, CONCLUSIONS: LOH On 3p can be detected in non-small cell lung carcinoma. Pa tients with loss of heterozigosity on 3p21 have a worse evolution after a c urative intended surgical resection.