This study investigated correlation between the lymph node metastasis, lymphatic invasion and the expression of several molecular markers which are reported to be associated with malignant potential of cancer cells. The markers which we measured in this study include cyclin D1, Rh, p16, p27 and PCNA as cell cycle regulator molecules, and E-cadherin, α- and β-catenin as intercellular adhesion molecules, Forty-three patients with superficial esophageal cancer who had had no prior chemotherapy and/or radiotherapy were enrolled in this study. Surgically resected samples were subjected to immunohistochemical analysis using antibodies against the above molecules. According to the tumor depth, the samples were classified into three groups; m1-m2 (group A): n=7, m3-sm1 (group B) n=9, and sm=2-3 (group C) n=27. For cyclin D1, strong expression was defined as abnormal expression, whereas for Rh, p16, p27, E-cadherin, α- and β-catenin, reduced expression was defined as abnormal one. For PCNA, per
centage of positive cells was calculated. Lymph node metastasis was positive in 0% in A, 11% in B and 33% in C group, while lymphatic invasion was positive in 14% in A, 33% in B and 41% in C group. As regard with adhesion molecules, tumors with at least one abnormal expression were seen in 20% in A, 60% in B and 84% in C group, which increased in coincidence with the extent of tumor depth. However, it did not show correlation with lymph node metastasis. As regadr with cell cycle regulators, the only molecule that showed correlation with lymph node metastasis was cyclin D1. Eight out of 20 cases which showed strong cyclin D1 expression had lymph node metastasis, whereas only 2 out of 28 cases which showed weak expression had lymph node metastasis (p<0.05), On the other hand, 26 out of 28 cases which showed no lymphatic invasion had no lymph node metastasis, while 8 out of 15 cases which showed positive lymphatic invasion had lymph node metastasis (p<0.01). These suggest that combination of cyclin D1 and lymphatic invasion may help more accurate prediction of lymph node metastasis from superficial esophageal cncers.
This study also investigated a risk factor for lymph node metastasis from colonic cancers using 123 superficial colonic cancer specimens. Tumor depth was defined acording to the distance from muscularis mucosa to the front of tumors as follows; sm1: 0-500μm, sm2: 500-1000μm , sm3: 1000-μm. Lymph node metastasis was seen in 0% in sm1, 2.0% in sm2 and 7.5% in sm3. The shortest distance of the tumors that had lymph node metastasis was 1200μm. Clinicopathological analysis revealed that the risk factor for lymph node metastasis was the distance from muscularis mucosa of more than 1200μm, lymphatic invasion, budding of the front of tumors and severe dysplasia.
At present, correlation between these factors and molecular markers such as MMP7, MMP9, S100, Rho, cadherin, catenin, KI-67, apotosis marker. Less