Cholecystectomy and the risk of alimentary tract cancers: A systematic review

Table 5 Descriptive characteristics of studies on the association between cholecystectomy and pancreatic cancer

Ref.	Period of study	Study design	No. of cases	No. of controls	Exposure ascertainment	Outcome ascertainment	Follow-up (yr)	Effect estimate	Adjustments	Quality of publication
Wynder et al[37], 1973	1950-1964	Case-control	11/142	16/307	Hospital records	NA	> 2	1.57 (0.76-3.24)1	Age, gender, race, hospital	28
Haines et al[38], 1982	1973-1978	Case-control	8/116	18/232	Hospital records	Medical records	≥ 5	0.89 (0.40-1.98)1	Age, gender, race, year of admission	27
Mack et al[39], 1986	1976-1981	Case-control	38/490	44/490	Hospital records	Pathology records	> 1	0.8 (0.5-1.4)	Age, gender, race	27
Cuzick and Babiker[40] 1989	1983-1986	Case-control	14/216	7/279	Hospital records	Medical records	NA	2.43 (0.91-7.12	Age, gender	29
Farrow and Davis[41] 1990	1982-1986	Case-control	8/218	6/188	Hospital records	Cancer registry	≥ 3	1.1 (0.3-3.4)	Age	29
Bueno de Mesquite et al[42], 1992	1984-1988	Case-control	24/176	44/487	Hospital records	Medical records	> 5	1.15 (0.55-2.40)	Age, response status, smoking	31
Lee et al[43], 1996	1989-1994	Case-control	12/282	6/282	Hospital records	Medical records	NA	2.04 (0.76-6.21)	Age, gender	43
Gullo et al[45], 1996	1987-1992	Case-Control	93/720	71/720	Hospital records	Medical records	> 1	1.00 (0.70-1.43)	Age, gender	34
Silverman et al[30], 2001	1986-1989	Case-Control	132/484	150/2099	Hospital records	Pathology records	> 2	1.77 (1.26-2.48)1	Age, race, gender, smoking, alcohol consumption, BMI, Calorie intake.	31
Ko et al[32], 2007	1995-1999	Case-control	75/532	155/1701	Hospital records	SEER abstracts	NA	1.73 (1.29-2.33)1	Ag, gender, BMI, smoking, diabetes	36
Hassan et al[44], 2007	2000-2006	Case-Control	808	808	Hospital records	Self reported	> 2	OR = 1.1 (0.9-1.8)	Age, gender, smoking, comorbidities	35
Zhang et al[31], 2014	1994-1998	Case-Control	215	676	Self report	Pathology reports	> 2	2.11 (1.32-3.35)	Age, gender, race, smoking, physical activity, diabetes	51
Nogueira et al[21], 2014	1992-2005	Case-control	1106/33280	2572/100000	Medicare database	Cancer registry	> 6	OR = 1.23 (1.15-1.33)	Age, gender, diabetes	49
Ichimiya et al[26], 1986	1953-1984	Cohort	3/1238	NA	National registry	Death registry	NA	SMR = 0.86 (0.33-2.25)1	Age, gender	33
Shibata et al[46], 1994	1981-1990	Cohort	65/13979	NA	Hospital records	NA	> 4	RR = 2.09 (0.99-4.39)	Age, gender, smoking	32
Ekbom et al[33], 1996	1965-1987	Cohort	261/62615	NA	National registry	Cancer registry	> 1	1.20 (1.06-1.36)	Age, gender	28
Chow et al[34], 1999	1977-1993	Cohort	184/42461	NA	National registry	Cancer registry	≥ 4	1.3 (1.1-1.6)	Age, gender, obesity, years of follow-up, other comorbidities	33
Coughlin et al[35], 2000	1982-1996	Cohort	3751/1.2 M	NA	Study database	Cancer registry	14	RR = 1.2 (1.0-1.5)	Age, gender, smoking, race, education, BMI, diet.	31
Ye et al[48], 2001	1965-1997	Cohort	730/268312	NA	National database	Cancer registry	≥ 2	SIR = 1.06 (0.98-1.14)	Age, gender, calendar year	35
Schernhammer et al[47], 2002	1976-1986	Cohort	37/145927	256/1675355	Self-report	Self report and death registry	> 10	1.23 (0.86-1.77)	Age, gender, BMI, Physical activity, diabetes	34
Goldacre et al[22], 2005	1963-1999	Cohort	127/39254	791/334813	NHS database	Cancer registry	≥ 2	1.06 (0.88-1.26)	Age, gender, calendar year, residence.	36
Arnold et al[36], 2009	1984-2004	Cohort	6243/1060389	NA	Hospital records	Death registry	NA	HR = 1.62 (1.02-2.55) blackHR = 1.10 (1.0-1.22) white	Age, gender, BMI, smoking, FH of pancreatic cancer, diabetes.	41
Chen et al[29], 2014	2000-2010	Cohort	16/5850		National database	Cancer registry	10	1.13 (0.60-2.12)	Age, gender, comorbidities	53

¹RR and 95% confidence intervals were calculated from raw data. NA: Not available; BMI: Body mass index.