Frequency and characteristics of synchronous gastric cancers: Need for improved awareness and better detection

Table 3 Risk factors for synchronous gastric neoplasms

Ref.	Older age	Male gender	Well differentiated PN	Lower stage of PN	AG/IM in background mucosa
Zhao et al[32], 2020					1
Zhu et al[33], 2020		1			1
Isobe et al[11], 2013	1	1
Jang et al[17], 2013	1
Lee et al[27], 2012		1	1		1
Fujita et al[44], 2010	1		1
Ribeiro et al[28], 2007			1	1
Otsuji et al[13], 2005	1		1	1
Arai et al[34], 2004	1	1	1
Lee et al[35], 2001	1	1		1
Takeshita et al[30], 1997	1	1	1
Seto et al[29], 1996	1	1	1
Kodama et al[25], 1996	1		1
Kosaka et al[26], 1990	1	1	1

1: Represent a positive relationship of the factor with synchronous gastric neoplasm; PN: Primary neoplasm; AG: Atrophic gastritis; IM: Intestinal metaplasia.