Differences in proximal (cardia) versus distal (antral) gastric carcinogenesis via retinoblastoma pathway

Table 1 Clinical data

	Proximal			Distal
	Biopsies normal	Biopsies IM	Cancer resections	Biopsies normal	Biopsies IM	Cancer resections
Number of subjects	56	49	39	52	50	78
Gender{F/M}	28/28	22/27	13/26	30/22	29/21	34/44
Age, years	50 (16)	58 (16)A	67 (11)B	52 (18)	59 (14)C	69 (10)D
Mean and (SD)
Tumour type			30 Intestinal			42 Intestinal
			9 Diffuse			36 Diffuse
TNM-stage,			T 3.1 (0.6)			T 3.0 (1.1)
mean and (SD)			N 1.0 (0.8)			N 1.0 (0.8)

There was a significant stepwise increase in patient age between patients with biopsies showing normal mucosa to patients with biopsies showing IM to patients with gastric cancer resections in both proximal and distal locations. A-D, P < 0.0001. SD = Standard deviation.

Table 2 Percentage of cases staining for and extent scores of p16 and pRb

	Proximal				Distal
	Biopsies	Biopsies	Resections	Resections	Biopsies	Biopsies	Resections	Resections
	normal	IM	UM	cancer	normal	IM	UM	cancer
Number and (%) of cases	12 (21%)	13 (27%)	8 (21%)	13 (33%)	4 (8%)	13 (26%)	37 (47%)	42 (54%)
positive for p16
Mean (and SD) of extent	0.21 (0.41)	0.27 (0.45)	0.23 (0.48)	0.41 (0.68)	0.077 (0.27)	0.26 (0.44)	0.49 (0.53)	0.69 (0.79)
scores for p16
Number and (%) of cases	52 (93%)	37 (76%)	31 (80%)	30 (77%)	46 (88%)	35 (70%)	51 (65%)	38 (49%)
positive for pRb
Mean (and SD) of extent	0.41 (0.5)	0.34 (0.48)	0.33 (0.48)	0.5 (0.51)	0.42 (0.5)	0.24 (0.43)	0.17 (0.38)	0.28 (0.45)
scores for pRb

SD: Standard deviation. UM: Uninvolved mucosa from cancer resections.

Table 3 p16 versus pRb staining in distal gastric carcinomas

		pRb
		+	-
p16	+	16	26
	-	22	14

This distribution was significant, P = 0.043.