ABSTRACT 1833(P7-6)
大腸粘膜下浸潤(sm)癌におけるp53蛋白発現と転移・再発との関係:平野晃一1, 2,溝口雅之1,山下 要1,渡辺美智夫1,藤本敏博1,高橋 豊1,磨伊正義1,源 利成2 (金沢大・がん研・1腫瘍外科,2遺伝子診断)
Expression of p53 protein in early invasive colorectal carcinomas with particular attention to correlation with metastasis and recurrence: Kouichi HIRANO1, 2, Masayuki MIZOGUCHI1, Kaname YAMASHITA1, Michio WATANABE1, Yutaka TAKAHASHI1, Masayoshi MAI1 and Toshinari MINAMOTO2 (Div. of 1Surg. Oncol. and 2Diag. Mol. Pathol., Cancer Res. Inst., Kanazawa Univ.)
To elucidate whether p53 overexpression correlates with the metastatic potential and other adverse prognostic factors in colorectal early invasive carcinomas (EIC). Overexpression of p53 protein was examined immunohistochemically in 50 paitiants with colorectal EIC. This overexpression was found in 20 paitiants (40 %). We detected p53 positive cells in 7 (78 %) of 9 patients that had metastasis to regional lymph nodes or distant organs or both, and in 13 (32 %) of 41 that had no metastasis (p=0.02). p53 immunoreactivivity was also present in 10 (71 %) of 14 superficial (type II) lesions compared with 10 (28 %) of 36 protruding (type I) tumors (p=0.009), and in 12 (57 %) of 21 moderately differentiated adenocarcnomas compared with 8 (28 %) of 29 well defferentiated adenocarcinomas (p=0.045). There was no signficant correlation between p53 overexpression and the depth of tumor invasion or angiolymphatic involvement. The p53-positive metastasizing tumors had features that corresponded to those of carcinoma arising de novo. Our results seem to support the postulate that p53 overexpression in colorectal EIC is associated with an increase in their metastatic potential.