Association between preoperative neutrophil-to-lymphocyte ratio and malignant intraductal papillary mucinous neoplasms: A systematic review and meta-analysis

Table 1 Characteristics of included studies

Ref.	Country	Study type	Years of data collection	Sample size	Gener (M/F)	Age	Benign group	Number	Malignant group	Number	NLR cutoff value	OR (95%CI)	NOS
Arima et al[36], 2015	Japan	Retro	December 1995 to February 2015	80	51/25	67.9	IPMA	52	IPMC	28	2.074	3.439 (1.10-11.8)	6
Gemenetzis et al[40], 2017	United States	Retro	January 1997 to July 2015	272	138/134	68 (61-75)	Benign + HGD	201	IC	71	4	6.62 (2.23-20.9)	7
Hata et al[37], 2019	Japan	Retro	January 1996 to December 2017	205	146/80	68 (34-85)	LGD	69	HGD + IC	136	2.5	2.905 (1.266-6.667)	7
Ohno et al[38], 2019	Japan	Retro	May 1996 to December 2017	56	33/23	71 ± 10/74 ± 8	IPMA	21	IPMC	35	2.2	9.79 (2.06-45.6)	6
Yamashita et al[6], 2019	Japan	Retro	January 1996 to December 2016	79	55/24	67 ± 8/70 ± 9	IPMA	49	IPMC	30	2.63	14.3 (1.01-211.71)	7
Li et al[7], 2021	China	Retro	November 2010 to February 2018	333	210/123	63 (19-83)	LGD	198	HGD + IC	135	2	2.487 (1.310-4.722)	6
Serafini et al[39], 2021	Italy	Retro	January 2005 to December 2015	83	45/38	69 (62-76)	LGD + IGD	37	HGD + IC	46	2.38	0.779 (0.327-1.855)	8
Sugimachi et al[8], 2021	Japan	Retro	2005-2020	50	24/26	68.0 ± 1.6/73.9 ± 2.3/72.7 ± 2.1	LGD + IGD	23	HGD + IC	27	3.1	7.16 (1.23-41.6)	6
Suzuki et al[9], 2021	Japan	Retro	2007-2018	121	73/48	68.7 (44-86)	LGD + HGD	100	IC	21	2.42	1.444 (0.559-3.732)	7
Maruyama et al[10], 2022	Japan	Retro	January 2013 to October 2018	76	46/30	73 (69-76)	LGD	35	HGD + IC	41	3.27	0.55 (0.21-1.45)	7

Retro: Retrospective study; M: Male; F: Female; NLR: Neutrophil-to-lymphocyte ratio; OR: Odds ratios; CI: Confidence interval; NOS: Newcastle-Ottawa Quality Assessment Scale; IPMA: Intraductal papillary mucinous adenoma; HGD: High-grade dysplasia; LGD: Low-grade dysplasia; IGD: Intermediate-grade dysplasia; IPMC: Intraductal papillary mucinous carcinoma; IC: Invasive carcinoma.