The impact of a multi-hospital network on the inequality in odds of receiving resection or ablation for synchronous colorectal liver metastases

Figures & data

Table 1. Patient characteristics for stage IV colorectal cancer patients with synchronous liver-only metastases according to hospital of diagnosis being an expert-hospital or a non-expert hospital .

	Total (n = 1624)	Nonexpert hospital (n = 1087)	Expert hospital (n = 537)	p-Value
	N (%)	N (%)	N (%)
Resection and/or ablation	505 (31.1)	308 (28.3)	197 (36.7)	<0.001
Year of diagnosis
2009–2012	605 (37.3)	379 (34.9)	226 (42.1)	<0.001
2013–2016	603 (37.1)	389 (35.8)	214 (39.9)
2017–2020	416 (25.6)	319 (29.4)	97 (18.1)
Hospital type (of diagnosis) ^b
General hospital	456 (28.1)	456 (42.0)	0 (0)	<0.001
Teaching hospital	968 (59.6)	631 (58.1)	337 (62.8)
University hospital	200 (12.3)	0 (0)	200 (37.2)
Gender
Male	995 (61.3)	658 (60.5)	337 (62.8)	0.387
Female	629 (38.7)	429 (39.5)	200 (37.2)
Age in years (median (IQR))	69 (61 – 77)	70 (62 – 78)	68 (60 – 76)	0.005
18–64	539 (33.2)	349 (32.1)	190 (35.4)
65–74	531 (32.7)	341 (31.4)	190 (35.4)
75+	554 (34.1)	397 (36.5)	157 (29.2)
Localization of primary tumor
Colon (C18)	1109 (68.3)	737 (67.8)	372 (69.3)	0.799
Rectosigmoid (C19)	41 (2.5)	27 (2.5)	14 (2.6)
Rectum (C20)	474 (29.2)	323 (29.7)	151 (28.1)
T-stadium^a
0–3	1005 (61.9)	672 (61.8)	333 (62.0)	0.613
4	292 (18.0)	190 (17.5)	102 (19.0)
X	327 (20.1)	225 (20.7)	102 (19.0)
N-stadium^a
N0	480 (29.6)	318 (29.3)	162 (30.2)	0.207
N+	977 (60.2)	647 (59.5)	330 (61.5)
X	167 (10.3)	122 (11.2)	45 (8.4)
Morphology				0.070
Adenocarcinoma	1453 (89.5)	962 (88.5)	491 (91.4)
Other	171 (10.5)	125 (11.5)	46 (8.6)
Differentiation grade
Well and moderately	945 (58.2)	657 (60.4)	288 (53.6)	0.015
Poorly and undifferentiated	173 (10.7)	103 (9.5)	70 (13.0)
Unknown	506 (31.2)	327 (30.1)	179 (33.3)
Social economic status
Low	513 (31.6)	325 (29.9)	188 (35.0)	<0.001
Mediate	619 (38.1)	436 (40.1)	183 (34.1)
High	280 (17.2)	162 (14.9)	118 (22.0)
Unknown	212 (13.1)	164 (15.1)	48 (8.9)
Comorbidities
0	671 (41.3)	420 (38.6)	251 (46.7)	<0.001
1	351 (21.6)	238 (21.9)	113 (21.0)
≥2	237 (14.6)	153 (14.1)	84 (15.6)
Unknown	365 (22.5)	276 (25.4)	89 (16.6)
Other treatments
Surgery on primary tumor	773 (47.6)	497 (45.7)	276 (51.4)	0.031
Chemotherapy	1115 (68.7)	729 (67.1)	386 (71.9)	0.049
Radiotherapy on primary tumor	347 (21.4)	231 (21.3)	116 (21.6)	0.871
Best supportive care/no active treatment	265 (16.3)	194 (17.9)	71 (13.2)	0.018

*At any point in time during the primary treatment journey.

^aBased on pathological staging, supplemented with clinical staging if missing.

^bFisher exact test was performed instead of Chi-square test for cell size <5.

Bold text is used to highlight values with statistical significance. 

Figure 1. Distribution of resection and/or ablation for synchronous colorectal liver-only metastases in a regional multi-hospital network (2009–2020).

Figure 2. Percentage of patients that received resection and/or ablation for SCLM according to hospital of diagnosis being an expert- or non-expert center.

Table 2. Multivariable logistic regression analyses on the likelihood of receiving resection and/or ablation for SCLM within a regional multi-hospital oncology network (n = 1624), over the overall study period and divided into time-intervals.

	Overall (n = 1624) 2009– 2020			Prenetwork (n = 605) 2009– 2012			Startup (n = 603) 2013– 2016			Matured-network (n = 416) 2017–2020
	OR	95% CI	p-Value	OR	95% CI	p-value	OR	95% CI	p-Value	OR	95% CI	P-Value
Hospital of diagnosis
Non-expert hospital	1.00			1.00			1.00			1.00
Expert hospital	1.32	(0.69– 2.55)	0.365	1.38	(0.35– 5.48)	0.581	1.66	(0.85– 3.24)	0.108	2.48	(0.81–7.59)	0.090
Gender
Male	1.00			1.00			1.00			1.00
Female	0.82	(0.64– 1.06)	0.130	0.72	(0.45– 1.15)	0.163	0.91	(0.60– 1.37)	0.639	0.74	(0.44–1.25)	0.254
Age
18 – 64	1.00			1.00			1.00			1.00
65 – 74	0.64	(0.48– 0.85)	0.002	0.70	(0.43– 1.15)	0.158	0.62	(0.40– 0.97)	0.037	0.69	(0.38–1.27)	0.237
75+	0.21	(0.15– 0.29)	<0.001	0.15	(0.08– 0.29)	<0.001	0.24	(0.14– 0.40)	<0.001	0.21	(0.11–0.41)	<0.001
Localization of primary tumor
Colon (C18)	1.00			1.00			1.00			1.00
Rectosigmoid (C19)	1.25	(0.59– 2.62)	0.561	0.26	(0.03– 2.31)	0.227	0.63	(0.10– 3.95)	0.622	3.00	(1.00–9.04)	0.051
Rectum (C20)	1.00	(0.76– 1.31)	0.978	1.01	(0.61– 1.67)	0.969	0.86	(0.56– 1.32)	0.495	0.97	(0.54–1.75)	0.931
T-stadium
0–3	1.00			1.00			1.00			1.00
4	0.81	(0.59 – 1.11)	0.186	0.88	(0.50 – 1.55)	.661	0.72	(0.42 – 1.25)	.242	0.61	(0.33 – 1.14)	.121
X	0.07	(0.04– 0.13)	<0.001	0.02	(<0.01– 0.12)	<0.001	0.12	(0.06– 0.26)	<0.001	0.03	(<0.01–0.22)	0.001
N-stadium
N0	1.50	(1.14– 1.97)	0.004	2.13	(1.28– 3.56)	0.004	1.29	(0.84– 1.98)	0.250	1.28	(0.73–2.24)	0.383
N+	1.00			1.00			1.00			1.00
Nx	0.29	(0.14– 0.61)	0.001	0.23	(0.06– 0.82)	0.023	0.37	(0.13– 1.05)	0.061	0.26	(0.03–2.31)	0224
Morphology
Adenocarcinoma	1.00			1.00			1.00			1.00
Other	0.81	(0.50–1.31)	0.388	1.17	(0.56– 2.45)	0.675	0.50	(0.17– 1.45)	0.201	1.10	(0.39–3.06)	0.858
Differentiation grade
Well and moderately	1.00			1.00			1.00			1.00
Poorly and undifferentiated	0.51	(0.33– 0.78)	0.002	0.82	(0.41– 1.63)	0.570	0.46	(0.23– 0.95)	0.035	0.62	(0.24–1.60)	0.392
Unknown	0.43	(0.31– 0.60)	<0.001	0.85	(0.49– 1.49)	0.567	0.35	(0.21– 0.60)	<0.001	0.21	(0.08–0.52)	<0.001
SES
Low	0.90	(0.66– 1.22)	0.490	0.83	(0.49– 1.42)	0.500	1.06	(0.68– 1.66)	0.798	1.22	(0.55–2.72)	0.618
Mediate	1.00			1.00			1.00			1.00
High	1.07	(0.75– 1.52)	0.729	1.21	(0.70– 2.10)	0.502	1.10	(0.63– 1.91)	0.744	0.79	(0.25–2.51)	0.687
Unknown	0.84	(0.51– 1.38)	0.479							0.92	(0.48–1.78)	0.810
Comorbidities
0	1.00			1.00			1.00			1.00
1	0.77	(0.56– 1.07)	0.115	0.55	(0.29– 1.05)	0.071	0.99	(0.58– 1.67)	0.966	0.70	(0.38–1.27)	0.239
≥2	0.63	(0.41– 0.95)	0.028	0.28	(0.11– 0.71)	0.007	1.03	(0.55– 1.93)	0.929	0.54	(0.25–1.17)	0.118
Unknown	0.82	(0.56– 1.18)	0.281	0.70	(0.37– 1.33)	0.269	1.10	(0.62– 1.96)	0.741	0.31	(0.10–0.95)	0.041
Period
Pre-network 2009 – 2012	1.00
Startup 2013 – 2016	1.24	(0.92 – 1.66)	0.156
Matured-network 2017 – 2020	1.33	(0.87 – 2.03)	0.186

Bold text is used to highlight values with statistical significance. 

Table 3. Multilevel multivariable logistic regression analyses on the likelihood of receiving resection and/or ablation for SCLM in the Netherlands (n = 12.357)* over the overall study period and divided into time-intervals.

	2009– 2020 (n = 12.357)			2009– 2012 (n = 4.600)			2013– 2016 (n = 4.382)			2017– 2020 (n = 3.375)
	OR	95% CI	p-Value	OR	95% CI	p-Value	OR	95% CI	p-Value	OR	95% CI	p-Value
Hospital of diagnosis
Non-expert hospital	1.00			1.00			1.00			1.00
Expert hospital	2.09	(1.77–2.47)	<0.001	1.41	(1.08– 1.84)	0.011	2.23	(1.82– 2.74)	<0.001	3.20	(2.21– 4.69)	<0.001
Gender
Male	1.00			1.00			1.00			1.00
Female	0.97	(0.88–1.07)	0.514	0.93	(0.79– 1.09)	0.348	1.04	(0.89– 1.21)	0.630	0.92	(0.76– 1.10)	0.356
Age
18–64	1.00			1.00			1.00			1.00
65–74	0.70	(0.63–0.78)	<0.001	0.66	(0.55– 0.79)	<0.001	0.76	(0.64– 0.91)	0.002	0.70	(0.56– 0.86)	0.001
75+	0.27	(0.24–0.31)	<0.001	0.23	(0.19– 0.29)	<0.001	0.30	(0.24– 0.37)	<0.001	0.30	(0.24– 0.37)	<0.001
Localization of primary tumor
Colon (C18)	1.00			1.00			1.00			1.00
Rectosigmoid (C19)	1.06	(0.81–1.40)	0.665	1.16	(0.76– 1.77)	0.502	0.98	(0.44– 2.17)	0.965	1.01	(0.65– 1.56)	0.980
Rectum (C20)	1.15	(1.03–1.27)	0.010	1.27	(1.05– 1.54)	0.012	0.92	(0.78– 1.09)	0.328	1.11	(0.91– 1.36)	0.299
T-stadium
0–3	1.00			1.00			1.00			1.00
4	0.63	(0.56–0.70)	<0.001	0.50	(0.41– 0.61)	<0.001	0.58	(0.48– 0.70)	<0.001	0.82	(0.66– 1.01)	0.068
X	0.04	(0.03–0.05)	<0.001	0.04	(0.02– 0.06)	<0.001	0.36	(0.21– 0.63)	<0.001	0.07	(0.04– 0.12)	<0.001
N-stadium
N0	1.52	(1.37–1.68)	<0.001	1.64	(1.36– 1.96)	<0.001	1.79	(1.50– 2.14)	<0.001	1.23	(1.01– 1.50)	0.041
N+	1.00			1.00			1.00			1.00
Nx	0.32	(0.24–0.44)	<0.001	0.27	(0.17– 0.42)	<0.001	0.36	(0.21– 0.63)	<0.001	0.34	(0.18– 0.65)	0.001
Morphology
Adenocarcinoma	1.00			1.00			1.00			1.00
Other	0.76	(0.62–0.91)	0.004	1.06	(0.78– 1.44)	0.704	0.81	(0.58– 1.13)	0.207	0.68	(0.45– 1.02)	0.061
Differentiation grade
Well and moderately differentiated	1.00			1.00			1.00			1.00
Poorly and undifferentiated	0.46	(0.39–0.54)	<0.001	0.53	(0.40– 0.69)	<0.001	0.43	(0.32– 0.57)	<0.001	0.50	(0.36– 0.69)	<0.001
Unknown	0.43	(0.38–0.48)	<0.001	0.70	(0.58– 0.85)	<0.001	0.36	(0.30– 0.44)	<0.001	0.20	(0.15– 0.27)	<0.001
SES
Low	0.94	(0.83–1.06)	0.312	0.93	(0.76– 1.14)	0.503	0.95	(0.79– 1.15)	0.618	0.84	(0.63– 1.12)	0.231
Mediate	1.00			1.00			1.00			1.00
High	1.08	(0.96–1.21)	0.229	1.00	(0.83– 1.22)	0.989	1.15	(0.96– 1.38)	0.130	1.10	(0.82– 1.48)	0.536
Unknown	0.89	(0.75–1.06)	0.201							0.85	(0.68– 1.07)	0.178
Comorbidities
0	1.00			1.00			1.00			1.00
1	0.89	(0.74–1.08)	0.247	0.96	(0.61– 1.50)	0.844	0.87	(0.67– 1.14)	0.304	0.77	(0.52– 1.14)	0.187
≥2	0.53	(0.40–0.70)	<0.001	0.31	(0.15– 0.64)	0.001	0.66	(0.45– 0.96)	0.031	0.44	(0.26– 0.75)	0.003
Unknown	0.61	(0.53–0.71)	<0.001	0.73	(0.54– 1.00)	0.049	0.83	(0.68– 1.00)	0.052	0.27	(0.20– 0.38)	<0.001
Period
Prenetwork 2009–2012	1.00
Startup 2013–2016	1.14	(1.02–1.28)	0.023
Matured-network 2017– 2020	1.24	(1.08–1.43)	0.003

*Except for patients diagnosed in hospitals affiliated with the network

Bold text is used to highlight values with statistical significance.  

Table 4. Multilevel Cox Proportional Hazard analyses on all patients with SCLM in The Netherlands (n = 13.981) over the overall study period and divided into time intervals.

	2009 – 2020 (n = 13.981)			2009 – 2012 (n = 5.205)			2013 – 2016 (n = 4.985)			2017 – 2020 (n = 3.791)
	HR	95% CI	p-Value	HR	95% CI	p-Value	HR	95% CI	p-Value	HR	95% CI	p-Value
Received resection and/or ablation for SCLM
No	1.00			1.00			1.00			1.00
Yes	0.32	(0.31–0.34)	<0.001	0.38	(0.34– 0.41)	<0.001	0.32	(0.30– 0.36)	<0.001	0.27	(0.24– 0.31)	<0.001
Hospital of diagnosis
Non-expert hospital	1.00			1.00			1.00			1.00
Expert hospital	0.93	(0.87–0.99)	0.022	.97	(0.89– 1.06)	0.520	0.90	(0.82– 0.99)	0.031	1.00	(0.88– 1.12)	0.929
Gender
Male	1.00			1.00			1.00			1.00
Female	1.06	(1.02–1.10)	0.004	1.04	(0.98– 1.10)	0.195	1.05	(0.99– 1.12)	0.120	1.09	(1.01– 1.18)	0.035
Age
18 – 64	1.00			1.00			1.00			1.00
65 – 74	1.16	(1.11–1.22)	<0.001	1.16	(1.08– 1.24)	<0.001	1.08	(1.00– 1.16)	0.058	1.28	(1.15– 1.42)	<0.001
75+	1.33	(1.26–1.40)	<0.001	1.29	(1.19– 1.40)	<0.001	1.24	(1.14– 1.35)	<0.001	1.43	(1.28– 1.58)	<0.001
Localization of primary tumor
Colon (C18)	1.00			1.00			1.00			1.00
Rectosigmoid (C19)	0.94	(0.84–1.06)	0.299	1.02	(0.86– 1.20)	0.839	0.76	(0.57– 1.03)	0.079	0.97	(0.80– 1.17)	0.722
Rectum (C20)	0.89	(0.84–0.94)	<0.001	.88	(0.80- 0.96)	0.005	0.88	(0.80– 0.98)	0.014	0.95	(0.84– 1.07)	0.420
T-stadium
0–3	1.00			1.00			1.00			1.00
4	1.39	(1.32–1.46)	<0.001	1.36	(1.25– 1.47)	<0.001	1.53	(1.41– 1.66)	<0.001	1.33	(1.21– 1.47)	<0.001
X	1.24	(1.18–1.31)	<0.001	1.30	(1.19– 1.42)	<0.001	1.26	(1.15– 1.38)	<0.001	1.27	(1.14– 1.42)	<0.001
N-stadium
N0	0.76	(0.72–0.79)	<0.001	0.68	(0.63– 0.73)	<0.001	0.74	(0.69– 0.80)	<0.001	0.89	(0.81– 0.97)	0.001
N+	1.00			1.00			1.00			1.00
Nx	0.99	(0.93–1.06)	0.832	0.91	(0.83– 1.00)	0.044	1.08	(0.96– 1.20)	0.195	1.17	(1.01– 1.36)	0.035
Morphology
Adenocarcinoma	1.00			1.00			1.00			1.00
Other	1.42	(1.34–1.51)	<0.001	1.04	(0.94– 1.15)	0.474	1.63	(1.47– 1.81)	<0.001	1.70	(1.50– 1.92)	<0.001
Differentiation grade
Well and moderately differentiated	1.00			1.00			1.00			1.00
Poorly and undifferentiated	1.64	(1.54–1.74)	<0.001	1.54	(1.40– 1.69)	<0.001	1.63	(1.46– 1.81)	<0.001	2.05	(1.78– 2.36)	<0.001
Unknown	1.17	(1.11–1.22)	<0.001	1.14	(1.06– 1.23)	<0.001	1.15	(1.06– 1.24)	<0.001	1.18	(1.06– 1.31)	0.003
SES
Low	1.02	0.97–1.07	0.404	1.00	(0.93– 1.07)	0.895	1.04	(0.97– 1.12)	0.297	1.07	(0.95– 1.20)	0.257
Mediate	1.00			1.00			1.00			1.00
High	0.96	(0.91–1.00)	0.067	0.93	(0.86– 1.00)	0.040	0.97	(0.90– 1.05)	0.494	0.98	(0.86– 1.12)	0.776
Unknown	1.05	(0.98–1.12)	0.206							1.06	(0.96– 1.18)	0.250
Comorbidities
0	1.00			1.00			1.00			1.00
1	1.07	(0.99–1.15)	0.098	0.99	(0.86– 1.14)	0.881	1.11	(1.00– 1.23)	0.061	1.11	(0.94– 1.31)	0.236
≥2	1.12	(1.03–1.22)	0.012	1.17	(1.00– 1.37)	0.054	1.19	(1.05– 1.35)	0.010	0.88	(0.72– 1.08)	0.215
Unknown	1.00	(0.94–1.05)	0.861	0.99	(0.89– 1.10)	0.881	0.97	(0.90– 1.06)	0.526	0.96	(0.84– 1.10)	0.572
Resection of primary tumor
No	1.00			1.00			1.00			1.00
Yes	0.44	(0.41–0.46)	<0.001	0.48	(0.44– 0.53)	<0.001	0.46	(0.42– 0.50)	<0.001	0.33	(0.30– 0.38)	<0.001
Chemotherapy
No	1.00			1.00			1.00			1.00
Yes	0.47	(0.45–0.49)	<0.001	0.43	(0.40– 0.46)	<0.001	0.48	(0.45– 0.52)	<0.001	0.45	(0.41– 0.49)	<0.001
Radiotherapy
No	1.00			1.00			1.00			1.00
Yes	0.85	(0.79–0.91)	<0.001	0.81	(0.73– 0.91)	<0.001	0.94	(0.84– 1.05)	0.262	0.70	(0.61– 0.81)	<0.001

* All SCLM patients in the Netherlands, including patients diagnosed in the network

Bold text is used to highlight values with statistical significance. 

Data availability statement

The data that support the findings of this study are available from the Netherlands Cancer Registry (NCR), maintained by the Netherlands Comprehensive Cancer Organization. Restrictions apply to the availability of these data, which were used under license for this study. Data are available with the permission of the Netherlands Comprehensive Cancer Organization.