Detection of mutant p53 gene at resection margin of the bronchus and cancer tissues to predict lung cancer recurrence.

Abstract

To investigate the mutations of p53 gene at the resection margins of the bronchus and cancer tissues , and to predict lung cancer recurrence. PCR-SSCP technique was used to detect mutation of p53 gene at the resection margin of the bronchus (no cancer cells remained by gross pathological examination) , cancer tissue and normal tissue of the lungs in 50 patients with lung cancers and 7 patients with non-cancerous pulmonary diseases. Local recurrence at the resection margin of bronchus and distant metastasis were investigated. Of the 50 patients , 14 cases (28 %) had p53 gene mutation at the resection margin of bronchus , and 28 cases (56 %) had p53 gene mutations in their cancer tissue. The mutations were not found in normal tissues of the 50 patients and in tissues of the 7 control patients. The mutation rate of p53 gene in cancer tissue was 100 %(2/ 2) for small cell lung cancer , 65 %(13/ 20) for squamous-cell carcinoma , 60 %(6/ 10) for adenosquamous cell carcinoma , 38. 9 %(7/ 18) for adenocarcinoma. Mutation rate of p53 gene was 72. 7 %(16/ 22) in stage III lung cancer , 58. 3 %(7/ 12) in stage II, 25 %(4/ 16) in stage I. During follow-up (ranged from 3 months to 16 months) , 6 of 14 patients (42. 9 %) with mutant p53 gene at the resection margin had local recurrence. There was no recurrence in patients without mutant p53 gene at the resection margin. Seventeen of 28 patients (60. 7 %) with mutant p53 gene in cancer tissue had recurrence or metastasis , but only 5 of 22 patients (22. 7 %) without mutant p53 gene had local recurrence ( P < 0. 05) . By testing mutations of p53 gene at the resection margins of bronchus , we may predict local recurrence of lung cancer. Patients with mutant p53 gene in cancer tissue appear to have a substantially increased risk of recurrence and metastasis of lung cancer.