Evaluation of metastatic potential of gastric tumors by staining for proliferating cell nuclear antigen and chromosome 17 numerical aberrations

Background: Aberrations in chromosome 17 are important in carcinogenesis. W e recently reported that numerical aberrations in chromosome 17 were associ ated with tumor progression in gastric cancer. The aim of this study was to determine the biological characteristics of gastric tumor cells with chrom osome 17 numerical aberrations. Methods: Gastric tumor sections (n = 105) and metastatic lymph nodes (n = 1 6) were stained simultaneously for PCNA (proliferating cell nuclear antigen ) and chromosome 17 centromere, Cancers were classified as follows: Group 1 : PCNA(+) and numerical chromosomal aberration(+); Group 2: PCNA(-) and num erical chromosomal aberration(+); Group 3: PCNA(+) and numerical chromosoma l aberration(-); and Group 4: PCNA(-) and numerical chromosomal aberration( -). Results: The frequency of Group 1 cells correlated with lymphatic invasion (P <.0001), lymph node metastasis (P <.0001), and venous invasion (P <.01). The frequency of these cells in gastric lesions was lower than in metastat ic lymph nodes (P <.01). Logistic regression analysis identified the depth of invasion followed by the frequency of Group I cells were two of the most significant independent factors that could predict lymph node metastasis a nd lymphatic invasion. Conclusions: The frequency of gastric tumor cells positive for PCNA and chr omosome 17 numerical aberrations may be an indicator of the metastatic pote ntial of gastric cancers.