[The clinical significance of detection of p53 gene mutation in patients with lung cancer].

Objective: To assess the value of detection of p53 gene mutation in bronchial biopsy and sputum samples for the diagnosis of lung cancer.

Methods: Bronchial biopsy and sputum samples were collected from 120 patients confirmed to have lung cancer and 40 patients with benign pulmonary diseases. Polymerase chain reaction-single strand conformation polymorphism-AgNOS(3) staining method (PCR-SSCP) was performed for the detection of point mutation at exon 5 - 8 of the p53 gene.

Results: The positive rates of p53 point mutation in the carcinomatous tissue, the para-carcinomatous tissue, the contralateral bronchial tissue and the sputum from patients with lung cancer were 60% (36/60), 17% (10/60), 5% (3/60) and 43% (26/60), respectively (P < 0.05). In patients with benign pulmonary diseases, p53 point mutation in bronchial biopsy sample was detected in only one case (5%). The positive rate for the diagnosis of lung cancer increased from 48% (cytology alone) to 68% when the detection of p53 point mutation and cytological examination for sputum samples were combined.

Conclusions: Detection of p53 gene mutation with PCR-SSCP-silver stain combined with cytological examination of sputum samples can improve the diagnosis of lung cancer.