Remnant gastric cancer: An ordinary primary adenocarcinoma or a tumor with its own pattern?

Table 1 Clinical and surgical characteristics of primary proximal gastric cancer and remnant gastric cancer groups

Variable	PGC, n = 120 (%)	RGC, n = 41 (%)	P value
Sex			0.216
Female	32 (26.7)	7 (17.1)
Male	88 (73.3)	34 (82.9)
Age in yr, mean ± SD	62.6 ± 12.7	68.1 ± 7.6	0.001
Body mass index in kg/cm², mean ± SD	24.9 ± 4.9	22.5 ± 4.2	0.006
Hemoglobin in g/dL, mean ± SD	12.5 ± 2.1	10.6 ± 2.2	< 0.001
Albumin in g/dL, mean ± SD	4.3 ± 3.2	3.8 ± 0.5	0.402
Neutrophil lymphocyte ratio, mean ± SD	3.02 (2.94)	3.01 (2.37)	0.994
Charlson–Deyo comorbidity index			0.391
0	76 (63.3)	29 (70.7)
> 1	44 (36.7)	12 (29.3)
American Society of Anesthesiologists			0.561
I/II	82 (68.3)	30 (73.2)
III/IV	38 (31.7)	11 (26.8)
Tumor site			0.002
Cardia Siewert II	16 (13.3)	0 (0)
Cardia Siewert III	32 (26.7)	5 (12.2)
Corpus/fundus	72 (60)	36 (87.8)
Surgical acess			0.693
Open	108 (90)	36 (87.9)
Laparoscopic	12(10)	5 (12.1)
Combined resection of other organs			0.789
No	96 (80)	32 (78)
Yes	24 (20)	9 (22)
Grade of Postoperative complication			0.867
0-I-II	98 (81.7)	33 (80.5)
III-IV	22 (18.3)	8 (19.5)
Hospital length of stay, mean ± SD	16.1 (9.1)	20.7 (17.9)	0.120
Neoadjuvant / adjuvant chemotherapy			< 0.001
No	43 (38.5)	29 (70.7)
Yes	77 (64.5)	12 (29.3)
Mortality
30 d	7 (5.8)	2 (4.9)	1.0
90 d	10 (8.3)	5 (12.2)	0.535

P values in bold are statistically significant. PGC: Proximal gastric cancer; RGC: Remnant gastric cancer; SD: Standard deviation.

Table 2 Pathological characteristics of primary proximal gastric cancer and remnant gastric cancer groups

Variables	PGC, n = 120 (%)	RGC, n = 41 (%)	P value
Tumor size, mean ± SD	5.1 (3.4)	5.3 (3.4)	0.785
Lauren type			0.302
Intestinal	68 (56.7)	27 (65.9)
Diffuse/mixed	52 (43.3)	14 (34.1)
Grade of histological differentiation			0.256
Well/moderately differentiated	55 (45.8)	23 (56.1)
Poorly differentiated	65 (54.2)	18 (43.9)
Lymphatic invasion			0.484
No	51 (42.5)	20 (48.8)
Yes	69 (57.5)	21 (51.2)
Venous invasion			0.069
No	75 (62.5)	32 (78)
Yes	45 (37.5)	9 (22)
Perineural invasion			0.602
No	50 (41.7)	19 (46.3)
Yes	70 (58.3)	22 (53.7)
pT			0.842
pT1/T2	46 (38.3)	15 (36.6)
pT3/T4	74 (61.7)	26 (63.4)
Number of resected LNs, mean ± SD	43.2 (20.8)	26 (14)	< 0.001
LN metastasis			0.204
pN0	45 (37.5)	20 (48.8)
pN+	75 (62.5)	21 (51.2)
Lymph node ratio			0.915
LR0	76 (63.3)	25 (61)
LR1	21 (17.5)	9 (22)
LR2	11 (9.2)	4 (9.8)
LR3	12 (10)	3 (7.3)
pTNM			0.773
I	36 (30)	13 (31.7)
II	27 (22.5)	11 (28.8)
III	57 (47.5)	17 (41.5)
Adjuvant chemotherapy			< 0.001
No	45 (37.5)	29 (70.7)
Yes	71 (62.5)	12 (29.3)
Recurrence			0.607
No	87 (72.5)	28 (68.3)
Yes	33 (27.5)	13 (31.7)
Pattern of recurrence1			0.322
Locoregional	11 (33.3)	5 (38.5)
Distant	12 (36.4)	5 (38.5)
Peritoneal	14 (42.4)	8 (61.5)

¹Patient can have more than one site of recurrence. P values in bold are statistically significant. PGC: Proximal gastric cancer; pTNM: Pathological tumor-node-metastasis; RGC: Remnant gastric cancer; LN: Lymph node; SD: Standard deviation.

Table 3 Univariate and multivariate analysis for disease-free survival and overall survival

Disease-free survival	Univariate			Multivariate			Overall survival	Univariate			Multivariate
Variables	HR	95%CI	P value	HR	95%CI	P value	Variables	HR	95%CI	P value	HR	95%CI	P value
Female (vs male)	0.78	0.41-1.48	0.445	-	-	-	Female (vs male)	1.13	0.66-1.93	0.658	-	-	-
Age ≥ 65 (vs < 65 yr)	0.85	0.47-1.51	0.570	-	-	-	Age ≥ 65 (vs < 65 yr)	1.19	0.74-1.90	0.467	-	-	-
ASA III/IV (vs I/II)	0.97	0.50-1.88	0.972	-	-	-	ASA III/IV (vs I/II)	1.51	0.92-2.48	0.101	-	-	-
Diffuse/mixed type (vs others)	1.43	0.80-2.54	0.228	-	-	-	Diffuse/mixed type (vs others)	1.18	0.73-1.89	0.495	-	-	-
Tumor size ≥ 4.0 cm (vs < 4.0 cm)	4.41	1.97-9.87	< 0.001	2.00	0.80-4.98	0.138	Tumor size ≥ 4.0 cm (vs < 4.0 cm)	2.12	1.24-3.63	0.006	1.35	0.72-2.53	0.351
pT3/pT4 status (vs pT1/pT2)	4.97	2.11-11.73	< 0.001	1.89	0.69-5.14	0.215	pT3/pT4 status (vs pT1/pT2)	2.29	1.31-4.01	0.004	1.38	0.70-2.72	0.347
pN+ (vs pN0)	9.21	3.30-25.73	< 0.001	5.79	1.92-17.45	0.002	pN+ (vs pN0)	2.75	1.57-4.81	< 0.001	2.10	1.12-3.96	0.021
non-CMT vs (CMT)	0.48	0.25-0.92	0.028	1.25	0.62-2.53	0.530	non-CMT vs (CMT)	0.96	0.60-1.55	0.867	-	-	-
RGC (vs PGC)	1.91	0.63-2.26	0.593	-	-	-	RGC (vs PGC)	0.98	0.57-1.67	0.930	-	-	-

P values in bold are statistically significant. HR: Hazard ratio; ASA: American Society of Anesthesiologists; CI: Confidence interval; CMT: Chemotherapy; HR: Hazard ratio; PGC: Proximal gastric cancer; RGC: Remnant gastric cancer.