Clinical significance of CT-defined minimal ascites in patients with gastric cancer

Table 1 Proportion of peritoneal carcinomatosis, distant metastasis, and CT-defined ascites in the patients with gastric cancer that completed diagnostic work-up including dynamic CT in January 2002–December 2002 at Boramae Hospital (BRM02)

	Peritoneal carcinomatosis
Distant metastasis	Negative	Positive	Unknown	Total
Negative	73 (67/6/0)1	11 (6/2/3)	0	84 (73/8/3)
Positive	5 (4/1/0)	4 (1/0/3)	8 (5/3/0)	17 (10/4/3)
Unknown	0	5 (1/0/4)	0	5 (1/0/4)
Total	78 (71/7/0)	20 (8/2/10)	8 (5/3/0)	106 (84/12/10)

¹CT-defined ascites (none/minimal/more than minimal).

Table 2 Clinical realities of CT-defined, preoperatively malignancy-undetermined ascites in the metastasis-free patients (BRM02-NoMeta)¹

	Surgery- or aspiration-recovered ascites
CT-defined ascites	Negative (%)	Positive (%)	Unknown (%)	Total (%)
No	68 (91.9)	5 (6.8)	1 (1.4)	74 (100)
Minimal	7 (87.5)	1 (12.5)	0 (0.0)	8 (100)
Mild	0 (0.0)	6 (85.7)	1 (14.3)	7 (100)
Total	75	12	2	89

¹Presence of ascites was not examined because operation was im-mediately ceased following observation of malignant omental cakes.

Table 3 Clinical realities of CT-defined, preoperatively malignancy-undetermined ascites in the metastasis-free patients (BRM02-NoMeta)¹

	Peritoneal carcinomatosis
CT-defined ascites	Negative (%)	Positive (%)	Total (%)
No	67 (90.5)	7 (9.5)	74 (100)
Minimal	6 (75.0)	2 (25.0)	8 (100)
Mild	0 (0.0)	7 (100)	7 (100)
Total	73	16	89

¹Presence of ascites was not examined because operation was im-mediately ceased following observation of malignant omental cakes.

Table 4 Clinical realities of CT-defined, preoperatively malignancy-undetermined ascites in the metastasis-free patients (BRM02-NoMeta)¹

	Peritoneal carcinomatosis
Surgery- or aspiration-Recovered ascites	Negative (%)	Positive (%)	Total (%)
Negative	69 (92.0)	6 (8.0)	75 (100)
Positive	4 (33.3)	8 (66.7)	12 (100)
Unknown	0 (0.0)	21 (100)	2 (100)
Total	73	16	89

¹Presence of ascites was not examined because operation was im-mediately ceased following observation of malignant omental cakes.

Table 5 Proportion of the minimal or mild CT-defined ascites at each UICC stage of gastric cancer

Stage	Minimal ascites (%)	Mild ascites (%)
1	9 (28.1)	0 (0)
2	4 (12.5)	1 (12.5)
3	5 (15.6)	1 (12.5)
4	14 (43.8)	6 (75.0)
Total	32 (100)	8 (100)

Table 6 Peritoneal carcinomatosis and surgically recovered ascites in the patients with minimal or mild CT-defined ascites

CT-definedascites	Peritoneal carcinomatosis		Significancevalue	Predictive
	Negative	Positive
Minimal	28 (27/1)1	4 (2/2)		NPV: 87.5%2
Mild	2 (1/1)	6 (2/4)	P<0.01

¹Surgically recovered ascites (negative/positive).

²NPV: negative predictive value of CT-defined ‘minimal’ ascites for peritoneal carcinomatosis, in comparison with CT-defined ‘mild’ ascites.

Table 7 Peritoneal carcinomatosis in the patients with CT-defined, yet preoperatively malignancy-undetermined ascites. Univariate analysis

Peritoneal carcinomatosis Significance Predictive value
	Negative	Positive
CT-defined enlarged lymph node (L/N)
None or Regional L/N	24	3		NPV: 88.9%1
Distant L/N	6	7	P<0.01
CT-defined perigastric invasion
Negative	20	2		NPV: 90.9%
Positive	10	8	P<0.05
Tumor size defined by endoscopy or UGIS
<3 cm	10	0		NPV: 100%
3-10 cm	16	6
>10 cm	4	4	P<0.05
EGC vs AGC2
EGC	7	0		NPV: 100%
AGC	23	10	NS

¹NPV: negative predictive value for peritoneal carcinomatosis. ²EGC: early gastric cancer; AGC: advanced gastric cancer.