Helicobacter pylori-negative gastric cancer: advanced-stage undifferentiated adenocarcinoma located in the pyloric gland area.

The incidence of Helicobacter pylori-negative gastric cancer (HpNGC) is extremely low. A 78-year old female without H. pylori infection was diagnosed with type 4 advanced-stage gastric prepylorus cancer. Distal gastrectomy was performed as for HpNGC (cT3N0M0). Histological findings of the resected specimen showed poorly differentiated adenocarcinoma and signet ring cell carcinoma, which were located in the pyloric gland area, diffusely invaded beyond the serosa without lymph node metastasis (pT4aN0M0). Most cases of undifferentiated-type HpNGC are diagnosed in the early stage and are located in the fundic gland area. We report the first case of advanced-stage undifferentiated HpNGC located in the pyloric gland area.