Gastric cancer with peritoneal metastases: Efficiency of standard treatment methods

Table 1 Clinical and pathological features of 200 intraperitoneally-disseminated gastric cancer patients

Characteristic		n (%)
Sex	Male	121 (60.5)
	Female	79 (39.5)
Primary gastric cancer location	Antral part	56 (28)
	Corpus	44 (22)
	Proximal part	7 (3.5)
	Antral part + corpus	34 (17)
	Corpus + proximal part	12 (6)
	Subtotal or total lesion	47 (23.5)
Borrmann’s type	Type I	3 (1.5)
	Type II	19 (9.5)
	Type III	106 (53)
	Type IV	72 (36)
Tumor histology	G1	5 (2.5)
	G2	12 (6)
	G3	54 (27)
	G4	98 (49)
	Signet ring cell	24 (12)
	Mucinous	3 (1.5)
	Unknown	4 (2)
Stage of peritoneal carcinomatosis according to Japanese classification (JGCA)	Р0 (Cyt+)	4 (2)
	Р1	46 (23)
	Р2	40 (20)
	Р3	110 (55)
PCI, points [Median = 13 (0-37)]	0 (Cyt+)	4 (2)
	1-6	64 (32)
	7-12	25 (12.5)
	13 and more	104 (52)
	Unknown	3 (1.5)
Ascites	Present	87 (43.5)
	Absent	113 (56.5)
Extraperitoneal metastases	Present	34 (17)
	Absent	166 (83)
Site of extraperitoneal metastases	Liver	10 (29)
	Non-regional lymph node	16 (47)
	Pleura	4 (12)
	Lung + non-regional lymph node	2 (6)
	Suprarenal gland	1 (3)
	Bones	1 (3)

JGCA: Japanese Gastric Cancer Association; PCI: Peritoneal cancer index.

Table 2 Treatment methods of 200 intraperitoneally-disseminated gastric cancer patients

Treatment modality		n (%)
BSC	Total	105 (52.5)
	Only BSC	31 (29.5)
	Attempted or non-resectable palliative surgery + BSC	74 (70.5)
	Stage of peritoneal carcinomatosis according to JGCA
	P0 (Cyt+)	0
	P1	20 (19)
	P2	23 (21.9)
	P3	62 (59.1)
	PCI
	0 (Cyt+)	0
	1-6	31 (29.5)
	7-12	13 (12.4)
	13 +	60 (57.2)
	Unknown	1 (0.9)
Palliative chemotherapy	Total	51 (25.5)
	Only palliative chemotherapy	24 (47)
	Attempted or non-resectable palliative surgery + palliative chemotherapy	27 (53)
	Stage of peritoneal carcinomatosis according to JGCA
	P0 (Cyt+)	0
	P1	6 (11.8)
	P2	9 (17.6)
	P3	36 (70.6)
	PCI
	0 (Cyt+)	0
	1-6	9 (17.6)
	7-12	8 (15.7)
	13 +	32 (62.7)
	Unknown	2 (4)
	Chemotherapy regimen
	CF	19 (37.2)
	5-FU	11 (21.6)
	CAF	10 (19.6)
	XELOX	7 (13.7)
	ECF	3 (5.9)
	Tegafur	1 (2)
Palliative gastrectomy	Total	44 (22)
	Only palliative gastrectomy	40 (91)
	Palliative gastrectomy + palliative chemotherapy	4 (9)
	Stage of peritoneal carcinomatosis according to JGCA
	P0 (Cyt+)	4 (9.1)
	P1	20 (45.4)
	P2	8 (18.2)
	P3	12 (27.3)
	PCI
	0 (Cyt+)	4 (9.1)
	1-6	24 (54.5)
	7-12	4 (9.1)
	13 +	12 (27.3)
	Lymph node dissection
	D0, 1	35 (79.5)
	D1+, 2	9 (20.5)
	Completeness of cytoreduction score
	CC-0	9 (20.5)
	CC-1	19 (43.2)
	CC-2	16 (36.3)

JGCA: Japanese Gastric Cancer Association; PCI: Peritoneal cancer index; CC: Completeness of cytoreduction; BSC: Best supportive care.

Table 3 Univariate analysis of prognostic factors for 200 intraperitoneally-disseminated gastric cancer patients

	n	1-yr survival, %	Median survival in mo	P value
Gender
Male	121	18.4	5.2	0.4
Female	79	18.5	6.5
Age
< 60	100	21.1	6.5	0.26
60+	100	15.4	5.0
Borrmann’s type
I-II	22	34.3	6.8	0.13
III-IV	178	16.5	5.2
Ascites
Absence	113	29.5	6.9	< 0.0001
Presence	87	1.7	4.0
Histology
G1	5	0	3.6	0.64
G2	12	40	6.8
G3	54	13.5	5.6
G4	98	21.2	5.2
Signet ring	24	9.5	6.5
Mucinous	3	0	3.7
Extraperitoneal metastases
No	165	19.7	6.4	0.031
Yes	34	7.7	4.2
JGCA classification
P0 (Cyt+)	4	0	4.0	< 0.0001
P1	46	47.2	9.8
P2	40	18.8	6.7
P3	110	5.1	4.0
PCI
0 (Cyt+)	4	0	4.0	< 0.0001
1-6	64	39.8	8.5
7-12	25	6.7	4.2
13+	104	5.5	4.1
Lymph node dissection
D0, 1	35	31.4	7.5	0.61
D1+, 2	9	50.0	8.9
Cytoreduction score
CC-0	9	22.2	7.5	0.065
CC-1	19	58.2	13.1
CC-2	16	18.8	4.7

JGCA: Japanese Gastric Cancer Association; PCI: Peritoneal cancer index; CC: Completeness of cytoreduction.

Table 4 Efficiency of standard treatment methods, depending on stage of peritoneal carcinomatosis according to the Japanese Gastric Cancer Association

	n	1-yr survival, %	Median survival in mo	P value
P1
BSC	20	38.5	8.5	0.12
Palliative chemotherapy	6	33.3	6.7
Palliative gastrectomy	20	61.1	17
BSC	20	38.5	8.5	0.71
Palliative chemotherapy	6	33.3	6.7
BSC	20	38.5	8.5	0.032
Palliative gastrectomy	20	61.1	17
Conservative approach of BSC + palliative chemotherapy	26	37.5	7.8	0.05
Palliative gastrectomy	20	61.1	17
P2
BSC	23	11.7	5	0.56
Palliative chemotherapy	9	22.2	8.4
Palliative gastrectomy	8	37.5	7.5
P3
BSC	62	2.3	3.2	0.003
Palliative chemotherapy	36	7.8	5.6
Palliative gastrectomy	12	8.3	4.7
BSC	62	2.3	3.2	0.2
Palliative gastrectomy	12	8.3	4.7
BSC	62	2.3	3.2	0.0006
Palliative chemotherapy	36	7.8	5.6

BSC: Best supportive care.

Table 5 Efficiency of standard treatment methods based on peritoneal cancer index level

	n	1-year survival, %	Median survival, mo	P value
PCI 1-6
BSC	31	30.8	8.3	0.089
Palliative chemotherapy	9	33.3	6.9
Palliative gastrectomy	24	54.5	12.6
BSC	31	30.8	8.3	0.94
Palliative chemotherapy	9	33.3	6.9
BSC	31	30.8	8.3	0.045
Palliative gastrectomy	24	54.5	12.6
Conservative approach of BSC + palliative chemotherapy	40	31.5	8.0	0.03
Palliative gastrectomy	24	54.5	12.6
D0,1 lymph node dissection	18	52.9	12.6	0.91
D1+, 2 lymph node dissection	6	60.0	17.0
PCI 7-12
BSC	13	0	2.1	0.082
Palliative chemotherapy	8	0	4.3
Palliative gastrectomy	4	50.0	4.2
PCI 13+
BSC	60	2.5	3.4	0.004
Palliative chemotherapy	32	8.9	6.0
Palliative gastrectomy	12	8.3	4.7
BSC	60	2.5	3.4	0.26
Palliative gastrectomy	12	8.3	4.7
BSC	60	2.5	3.4	0.0008
Palliative chemotherapy	32	8.9	6.0

PCI: Peritoneal cancer index; BSC: Best supportive care.