BACKGROUND: The growth pattern of early gastric carcinoma, based on a volumetric analysis, reflects biologic characteristics of the tumor. The authors investigated the microvessel density (MVD), expression of vascular endothelial growth factor (VEGF), and growth patterns in early gastric carcinoma. METHODS: Ninety-four tissue specimens resected from patients with early gastric carcinoma invading the submucosal layer were examined. Microvessel quantification was performed immunohistochemically using a monoclonal antibody against factor VIII-related antigen. VEGF expression was studied using an anti-VEGF polyclonal antibody. Growth patterns were defined as follows: Pen A type: expansively penetrating growth; Pen B type: infiltratively penetrating growth; Super type: superficially spreading growth. RESULTS: The mean MVD was 16.9 (range, 5.2-43.0). MVD was significantly higher in tumors with venous invasion (P<0.01), lymphatic vessel invasion (P<0.05), and lymph node metastases (P<0.05) compared with MVD in tumors without venous or lymphatic vessel invasion or lymph node metastases. The VEGF-positive rate of Pen A type tumors was 66.7% (18 of 27), that Pen B type was 10.0% (1 of 10), that of Super type was 19.4% (6 of 31), and that of the unclassified type was 15.4% (4 of 26). The VEGF-positive rate in patients with Pen A type tumors was significantly higher than that in patients with the other three growth patterns(P<0.01). MVD in patients with Pen A type tumors (25.9+/-9.2) was significantly higher than that in patients with Super type tumors (12.6+/-5.4) (P<0.01). Patients with Pen A type tumors had a poorer prognosis than patients whose tumors had other growth patterns (P<0.05). According to multivariate analysis, VEGF expression and lymphatic vessel invasion were significant prognostic factors. CONCLUSIONS: Pen A type gastric carcinoma tends to secrete VEGF, thus inducing tumor angiogenesis and resulting in venous invasion. Intensive follow-up is necessary for patients with Pen A type tumors, because this tumor type has a greater propensity for hematogenous metastasis.
BACKGROUND: The growth pattern of early gastric carcinoma, based on a volumetric analysis, reflects biologic characteristics of the tumor. The authors investigated the microvessel density (MVD), expression of vascular endothelial growth factor (VEGF), and growth patterns in early gastric carcinoma. METHODS: Ninety-four tissue specimens resected from patients with early gastric carcinoma invading the submucosal layer were examined. Microvessel quantification was performed immunohistochemically using a monoclonal antibody against factor VIII-related antigen. VEGF expression was studied using an anti-VEGF polyclonal antibody. Growth patterns were defined as follows: Pen A type: expansively penetrating growth; Pen B type: infiltratively penetrating growth; Super type: superficially spreading growth. RESULTS: The mean MVD was 16.9 (range, 5.2-43.0). MVD was significantly higher in tumors with venous invasion (P<0.01), lymphatic vessel invasion (P<0.05), and lymph node metastases (P<0.05) compared with MVD in tumors without venous or lymphatic vessel invasion or lymph node metastases. The VEGF-positive rate of PenA type tumors was 66.7% (18 of 27), that Pen B type was 10.0% (1 of 10), that of Super type was 19.4% (6 of 31), and that of the unclassified type was 15.4% (4 of 26). The VEGF-positive rate in patients with PenA type tumors was significantly higher than that in patients with the other three growth patterns(P<0.01). MVD in patients with PenA type tumors (25.9+/-9.2) was significantly higher than that in patients with Super type tumors (12.6+/-5.4) (P<0.01). Patients with PenA type tumors had a poorer prognosis than patients whose tumors had other growth patterns (P<0.05). According to multivariate analysis, VEGF expression and lymphatic vessel invasion were significant prognostic factors. CONCLUSIONS:Pen A type gastric carcinoma tends to secrete VEGF, thus inducing tumor angiogenesis and resulting in venous invasion. Intensive follow-up is necessary for patients with PenA type tumors, because this tumor type has a greater propensity for hematogenous metastasis.