Endoscopic tattooing of colorectal lesions: Is it a risk-free procedure?

Table 1 Summary of the accuracy, false positive and spillage rates of endoscopic tattooing for localization before surgery from previously published reports

Authors	n	Substances	Techniques	Mean interval	Accuracy (%)	False positive (%)	Invisible (%)	Spillage (%)
Cho et al[9]	96	India ink	NA	6 d	97.9	0	2.1	6.3
Fu et al[15]	36	India ink	0.2 mL injected directly	30.8 d	86	0	14	8.3
	55	India ink	0.2 mL injected after 3 mL injection of saline solution	17.6 d	98	0	2	1.8
Arteaga-González et al[16]	21	India ink	Total 0.2-0.5 mL of 90% India ink injected after 3 mL injection of saline solution	NA	100	0	0	14.3
Park et al[17]	63	Spot	1-1.5 mL injected after 1 mL injection of saline solution	1 d (all)	96.8	1.6	1.6	9.5
Feingold et al[18]	50	Spot	1-4 mL tangentially injected into multiple sites distal to the lesions	1 d (60%)	88	0	12	NA
Conaghan et al[19]	54	Spot	NA	NA	70	7	15	NA
Hwang et al[20]	20	Spot	0.5 mL injected after 0.5 mL injection of saline solution, 3 sites at 1 cm distal to the lesions	3 d	90	0	10	5
Miyoshi et al[21]	41	Indocyanine green	1 mL injected after 2 mL injection of saline solution	4 d	92.7 (100, ≤ 8 d)	0	7.3 (> 9 d)	2.4

NA: Not available.