Expression of vascular endothelial growth factor C in renal cell carcinoma and its correlation with pathological parameters and prognosis

BACKGROUND: Renal cell carcinoma (RCC) is a common malignant tumor of the urinary system. This study aimed to analyze the expression of vascular endothelial growth factor C (VEGF-C) in RCC and its relationship with pathological parameters and prognosis. METHODS: The clinical data of 68 patients who underwent surgical treatment and confirmed to be RCC by pathology from February 2012 to January 2014 were collected. The specimens of carcinoma tissues of the 68 patients were collected, among which 20 patients were collected from normal tissue specimens adjacent to the cancer more than 5 cm away from the tumor as controls. The VEGF-C expression level was detected by immunohistochemistry, and the relationship between VEGF-C expression and clinical pathological parameters and prognosis of RCC was analyzed. RESULTS: The positive expression rate of VEGF-C in cancer tissues of RCC patients was significantly higher than the adjacent tissues (85.29% vs. 15.00%) (P<0.05). The positive expression rate of VEGF-C in cancer tissues of RCC patients with low-to- moderate differentiation, stage III–IV, and lymph node metastasis was higher than that of RCC patients with high differentiation, stage I–II, and no lymph node metastasis (P<0.05). The survival rates of RCC patients at 1-, 3- and 5-year follow-up were 82.35% (56/68), 54.41% (37/68), and 32.35% (22/68), and the survival time of patients with positive VEGF-C expression was shorter than patients with negative expression (P<0.05). There was no significant difference in the 5-year survival rate among RCC patients according to sex or presence of muscular infiltration (P>0.05). Meanwhile, the 5-year survival rate was higher in patients with tumor diameter <5 cm, high differentiation, stage I–II, no lymph node metastasis, VEGF-C–negative expression, and aged <55 years old (P<0.05). The Cox regression model analysis showed that differentiation degree, clinical stage, lymph node metastasis, and VEGF-C expression were all independent risk factors affecting the prognosis of RCC patients (P<0.05). CONCLUSIONS: VEGF-C is highly expressed in cancer tissues of RCC patients, and is related to clinical stage, pathological differentiation, and lymph node metastasis, which maybe an effective factor of prognosis prediction.