Table 3.

Uni- and multivariable comparison of disease-free survival between patients with synchronous versus metachronous colorectal peritoneal metastases after CRS with HIPEC

Variables	Univariate analysis			Multivariate analysis
	HR	95% CI	p Value	HR	95% CI	p Value
Onset of colorectal PM
Synchronous	1.00	–	–	1.00	–	–
Metachronous	1.51	1.19–1.93	0.001	1.63	1.18–2.26	< 0.01
Age	0.99	0.98–1.00	0.20
Sex
Female	1.00	–	–
Male	1.01	0.79–1.28	0.95
Primary tumor
Rectum	1.00	–	–	1.00	–	–
Right colon	0.95	0.65–1.93	0.79	1.00	0.66–1.52	0.99
Transverse colon	0.76	0.44–1.32	0.34	0.75	0.41–1.38	0.35
Left colon	1.05	0.63–1.73	0.86	1.5	0.66–2.00	0.63
Sigmoid	0.91	0.62–1.33	0.62	0.81	0.53–1.23	0.32
Signet cell histology
No	1.00	–	–	1.00	–	–
Yes	1.23	0.79–1.90	0.36	1.18	0.70–1.99	0.53
PCI score during CRS with HIPEC
0–5	1.00	–	–	1.00	–	–
6–10	1.47	1.07–2.04	0.02	1.33	0.96–1.88	0.09
11–15	2.06	1.42–2.99	< 0.001	2.05	1.38–3.07	< 0.001
16–20	1.99	1.27–3.11	< 0.01	1.94	1.22–3.09	< 0.01
> 20	2.00	0.99–4.02	0.05	2.28	1.10–4.71	0.03
CC score
CC-0 or CC-1	1.00	–	–
CC ≥ 2	3.84	0.54–27.58	0.18
Prior chemotherapy
No	1.00	–	–	1.00	–	–
Yes	1.41	1.10–1.81	< 0.01	1.07	0.78–1.47	0.67
Neoadjuvant chemotherapy (CRS with HIPEC)
No	1.00	–	–
Yes	0.99	0.74–1.32	0.93
Adjuvant chemotherapy (CRS with HIPEC)
No	1.00	–	–	1.00	–	–
Yes	0.63	0.54–0.81	< 0.001	0.72	0.54–0.97	0.03
Neoadjuvant biologic therapy (CRS with HIPEC)
No	1.00	–	–
Yes	1.20	0.76–1.89	0.44

HR hazard ratio, CI confidence interval, PM peritoneal metastases, PCI Peritoneal Cancer Index, CRS cytoreductive surgery, HIPEC hyperthermic intraperitoneal chemotherapy, CC score completeness of cytoreduction score