Perigastric lymph node status as a prognostic indicator in patients with gastric cancer

The extent of lymph node dissection and histological examination of dissected lymph nodes varies among countries, which leads to the erroneous nodal stage and different surgical results in gastric cancer (stage migration, 'Will Rogers effect'). The aim of this study was to clarify the prognostic significance of the number of positive perigastric lymph nodes, which could be evaluated simply after D1 gastrectomy.

A consecutive series of 106 patients with histologically node-positive gastric cancer treated by radical gastrectomy and lymph node dissection (D2 or D3) was studied. The number of metastatic perigastric nodes (level I, nos 1-6) was examined, and its influence on the survival of patients was analysed.

The overall 5-year survival rate was 50.9 per cent; the 5-year survival rate was significantly decreased when positive perigastric nodes exceeded six (62 per cent for one to six nodes versus 23 per cent for seven or more nodes, P< 0.001). Tumours having one to six positive perigastric nodes compared with those having seven or more positive perigastric nodes were more likely to have a size less than 4 cm (29 per cent versus one of 30, P< 0.001), grossly localized type (45 per cent versus seven of 30, P=0.042), absence of serosal invasion (32 per cent versus none of 30, P=0.002) and metastasis limited to the perigastric lymph nodes (70 per cent versus seven of 30, P < 0.001).

The results indicate that the number of positive perigastric nodes correlates with tumour progression and patient survival. This parameter is a simple and useful prognostic indicator for node-positive gastric cancer, and is available not only for D2 and D3 gastrectomy but also for D1 gastrectomy.