Long-lasting discussion: Adverse effects of intraoperative blood loss and allogeneic transfusion on prognosis of patients with gastric cancer

Table 1 Studies of effects of intraoperative blood loss on prognosis in patients with gastric cancer

Study	Period	Sample size	Selected group	Amount of IBL	Patients received BTF	Adverse effect of BTF on prognosis	Adverse effect of IBL on prognosis
Dhar et al[7], 2000	1979-1989	152	T2N0–T3N2	> 500 ml	Not specified	-	Yes (Survival)
Kamei et al[14], 2009	1992-2003	146	Curative Gastrectomy	≥ 475 mL	Included (13%)	No (Peritoneal recurrence)	Yes (Peritoneal recurrence)
Liang et al[8], 2013	2003-2007	845	stage I-III	≥ 200 ml	Included (25%)	No (Survival)	Yes (Survival)
Ishino et al[18], 2014	2001-2012	214	Laparoscopic,stage I-II	≥ 1% body weight	0%	-	Yes (Survival)
Arita et al[15], 2015	1997-2012	540	Curative Gastrectomy	> 326 ml	Not specified	-	Yes (Peritoneal recurrence)
Mizuno et al[9], 2016	1999-2015	203	stage II/III	≥ 400 mL	Not specified	-	Yes (Survival, Recurrence)
Ito et al[10], 2018	2010-2014	1013	stage II/III	> 330 mL	Not specified	-	Yes (Recurrence)
Ojima et al[19], 2009	1991-2002	856	Curative gastrectomy	≥ 1000 mL	Included (18%)	Yes (Survival)	No (Survival)
Squires et al[20], 2015	2000-2012	765	Curative gastrectomy	> 250 mL	Included (22%)	Yes (Survival, Recurrence)	No (Survival, Recurrence)
Kanda et al[6], 2016	1999-2014	250	stage II/III	≥ 800 mL	Included (23%)	Yes (Survival, Recurrence)	No (Survival)

IBL: Intraoperative blood loss; BTF: Blood transfusion.

Table 2 Studies of effects of blood transfusion on prognosis in patients with gastric cancer

Study	Period	Sample size	Selected group	Rates of received BTF	Timing of transfusions	Adverse effect of BTF on prognosis
Kaneda et al[44], 1987	1976-1980	231	Not specified	51%	Not specified	Yes (Survival)
Ojima et al[19], 2009	1991-2002	856	Curative gastrectomy	18%	Pre + Intra + Post	Yes (Survival)
Squires et al[20], 2015	2000-2012	765	Curative gastrectomy	22%	Intra + Post	Yes (Survival, Recurrence)
Kanda et al[6], 2016	1999-2014	250	stage II /III	23%	Pre + Intra + Post	Yes (Survival, Recurrence)
Kampschoer et al[45], 1989	1976-1981	1000	Curative gastrectomy	37%	Pre + Intra + Post	No (Survival)
Kamei et al[14], 2009	1992-2003	146	Curative gastrectomy	13%	Not specified	No (Peritoneal recurrence)
Pacelli et al[46], 2011	1990-2005	927	Curative gastrectomy	35%	Pre + Intra + Post	No (Survival)
Liang et al[8], 2013	2003-2007	845	stage I-III	25%	Pre + Intra + Post	No (Survival)
Rausei et al[47], 2013	1995-2011	224	stage I-III	20%	Pre + Intra + Post	No (Survival)

BTF: Blood transfusion; Pre: Preoperative; Intra: Intraoperative; Post: Postoperative.

Table 3 Systematic reviews and meta-analyses of effects of blood transfusion on prognosis in patients with gastric cancer

Study	Rate of received	Adverse effect on OS	Adverse effect on CSS	Adverse effect on RFS	Adverse effect on PCs
	BTF patients
Sun et al[1], 2015	36.3%	Yes,	Yes,	Yes,	Not specified
		HR, 2.17;	HR, 2.57;	HR, 1.52;
		95%CI, 1.86-2.37	95%CI, 1.24-5.34	95%CI, 1.08-2.15
Li et al[2], 2015	44.8%	Yes,	Not specified	Yes,	Yes,
		HR, 1.26;
				HR, 1.36;	HR, 3.33;
		95 % CI, 1.21-1.31
				95%CI, 1.02-1.81	95%CI, 1.02-1.81
Agnes et al[3], 2018	Not specified	Yes,	Yes,	Yes,	Yes,
		HR, 1.34;	HR, 1.66;	HR, 1.48;	HR, 1.36;
		95%CI, 1.23-1.45	95%CI, 1.50-2.19	95%CI, 1.18-1.86	95%CI, 2.10-5.29

BTF: Blood transfusion; OS: Overall survival; CSS: Cancer-specific survival; RFS: Relapse-free survival; PCs: Postoperative complications; HR: Hazard ratio; CI: Confidence interval.