Biological behavior of the intramucosal Helicobacter pylori-negative undifferentiated-type early gastric cancer: comparison with Helicobacter pylori-positive early gastric cancer

Background The differences in the growth morphology, proliferative ability, and background mucosa of the cancer between Helicobacter pylori (HP)-positive (HP+) gastric cancer (GC) and HP-negative (HP−) GC are still unclear. To clarify the differences, we compared the characteristics of the two types of cancer.