['Metastasis to the liver or lymph nodes is an important prognostic factor in patients with colorectal carcinoma. The purpose of the current study was to estimate the power of tumor thickness in predicting metachronous liver metastasis (MLM), lymph node metastasis (LNM), or overall survival (OS) in patients at two hospitals (the National Cancer Center Hospital [NCCH] and the National Cancer Center Hospital East [NCCHE]) to confirm the reproducibility of the study.', 'The subjects of this study were 74 and 186 consecutive patients with ulcerative-type colorectal carcinoma treated at the NCCH and NCCHE, respectively. Tumor thickness was measured in three areas: 1) the marginal elevated area (MEA), 2) the central depressed area (CDA), and 3) the most thickened area (MTA). Studies were performed with well known histologic parameters to compare the predictive power of tumor thickness on MLM, LNM, and OS using the Cox proportional hazards regression model or analysis of variance.', 'A significant correlation between tumor thickness and MLM was observed only in the CDA in the NCCH patients (P = 0.005). The authors applied a tumor thickness cutoff value in the CDA of 10 mm (</= 10 mm and > 10 mm) for further study. Multivariate analyses demonstrated that a tumor CDA thickness > 10 mm was associated significantly with MLM, multiple LNMs, and OS in NCCH patients with Dukes Stage C disease (P = 0.002, P = 0.023, and P = 0.002, respectively). A significant predictive power for tumor CDA thickness for MLM, multiple LNMs, and OS was confirmed by multivariate analysis in NCCHE patients with Dukes Stage C disease (P = 0.008, P = 0.021, and P = 0.010, respectively).'] Is tumor thickness a histopathologic predictive parameter of tumor metastasis and prognosis in patients with Dukes stage C ulcerative-type colorectal carcinoma . A two-hospital-based study?