[Diagnosis of lymph node micrometastases in human lung carcinoma: determination of p53 gene mutations by polymerase chain reaction-temperature gradient gel electrophoresis (PCR-TGGE)].
OBJECTIVE
Metastasis is one of the most important factors in determining the prognosis of lung cancer patients. However, it is difficult to determine single cancer cell in lymph nodes by routine methods. This study was designed to investigate a sensitive method for detecting lymph node micrometastases in human lung carcinomas.


METHODS
Mutation detection for p53 gene (exon 5-8) was performed in 39 cases of primary lung carcinomas and 110 corresponding lymph nodes (LNS) by PCR-TGGE method. Serial sectioning was performed to confirm micrometastases in some of these samples.


RESULTS
p53 mutations were found in 23 of 39 cases with primary lung cancer. Forty LNSs showed p53 mutation in 67 corresponding LNSs. They were located at the same exon as their primary tumors. Only twenty-six LNSs were detected metastases by routine histopathology. Forty-three LNSs from sixteen cases of primary tumor without p53 mutation and ten LNSs from the patients without tumor disease did not have any p53 mutations. By PCR-TGGE assay p53 gene mutations were determined in fourteen LNSs without histopathological evidence of metastasis. Micrometastases were found in four of the serially sectioned cases.


CONCLUSIONS
Mutation detection for p53 gene (exon 5-8) showed lymph node micrometastases in patients with lung carcinoma. It may be used as a complement for the routine histopathology.
Xu
Mei-Lin
ML
Department of Pathology, Tianjin Chest Hospital, Tianjin, 300051, P.R.China. meilinxu-gh@163.com
Wu
Bing-Quan
BQ
Zhong
Hao-Hao
HH
Yang
Xia
X
Heng
Wan-Jie
WJ
D000230:Adenocarcinoma / Q000235:genetics / Q000556:secondary; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000556:secondary; D004587:Electrophoresis, Agar Gel; D005260:Female; D016158:Genes, p53; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics / Q000473:pathology*; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016133:Polymerase Chain Reaction; D012680:Sensitivity and Specificity