Abstract
The combined examination using serum PG and Hp testing for gastric cancer screening overlooks gastric cancer cases negative for both tests (PG-/Hp-). In order to study the issues related to PG-negative gastric cancers detected through Hp testing, we simultaneously conducted PG testing, various Hp-related antibody testing, including anti-Hp antibody and anti-cytotoxin-associated gene A (CagA) antibody, and 13C-UBT on a total of 188 gastric cancer patients in the present study. The positive rate in the PG testing was 76.1 %. Of the PG-negative gastric cancer cases, 73.3 - 82.2 % were positive in the Hp-related antibody tests, but 4.4 - 6.7% were false negative. Whereas 13.3 - 22.2 % of PG-negative gastric cancer cases resulted in Hp-related antibody tests (-) / 13C-UBT (-), but the majority of them were accompanied by progressive gastric mucosal atrophy clearly identified by endoscopy, indicating a past history of Hp infection. These cases were frequent in seniors, and their PG I and II values were both markedly low. The corresponding PG-/Hp- cases should be carefully handled, considering the potential risk of gastric cancer development.
