Background: To investigate the mutations of p53 gene at the resection margins of the bronchus and cancer tissues , and to predict lung cancer recurrence.
Methods: 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.
Results: 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) .
Conclusions: 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.