Table 1.

Methods to histologically evaluate the presence and pattern of principal cells in the glandular stomach. Evaluation performed at 40X High-Power Field (HPF).

	Score	Description
Presence of principal cells	0	None, 0–15 cells per HPF
	1	Scarce, 16–50 cells per HPF
	2	Moderate, 51–90 cells per HPF
	3	Abundant, >90 cells per HPF
Pattern of principal cell organization	a	Principal cells well stained with HE, organized in “closed rosettes”
	b	Principal cells poorly or scantly stained by HE and interspersed between parietal cells