Comparison of open and closed hyperthermic intraperitoneal chemotherapy: Results from the United States hyperthermic intraperitoneal chemotherapy collaborative

Table 2 Multivariable analysis for overall survival based on histology

Factor		OS entire cohort			OS appendiceal cohort			OS colorectal cohort
		HR	95%CI	P value	HR	95%CI	P value	HR	95%CI	P value
Age	< 65	Reference			Reference			Reference
	≥ 65	1.07	0.79-1.45	0.65	1.21	0.80-1.81	0.37	0.87	0.54-1.39	0.57
Previous CRS	No	Reference			Reference			Reference
	Yes	1.22	0.91-1.64	0.18	1.51	1.01-2.24	0.04	1.10	0.69-1.73	0.68
Histology	Appendiceal	Reference
	Colorectal	2.75	1.99-3.78	< 0.01
Differentiation	Well	Reference			Reference			Reference
	Mod / poor	3.22	2.28-4.55	< 0.01	3.92	2.63-5.82	< 0.01	1.55	0.79-3.06	0.20
ASA	1-2	Reference			Reference			Reference
	3-4	1.98	1.17-3.32	0.01	1.83	0.94-3.56	0.07	2.01	0.84-4.79	0.11
PCI	< 20	Reference			Reference			Reference
	≥ 20	1.86	1.34-2.57	< 0.01	1.86	1.21-2.88	< 0.01	1.94	1.17-3.21	0.01
PIC dose	Low dose	Reference			Reference			Reference
	High dose	1.35	0.91-2.02	0.13	1.16	0.67-2.01	0.58	1.49	0.65-3.42	0.33
CCR	0-1	Reference			Reference			Reference
	2-3	2.33	1.49-3.63	< 0.01	2.15	1.28-3.61	< 0.01	5.74	1.99-16.56	< 0.01
Complications	0 – II	Reference			Reference			Reference
	III – V	1.61	1.20-2.14	< 0.01	1.23	0.81-1.86	0.31	1.96	1.26-3.05	< 0.01
Adjuvant chemo	No	Reference			Reference			Reference
	Yes	1.16	0.86-1.56	0.31	1.33	0.87-2.05	0.18	0.98	0.65-1.48	0.94
PIC method	Open	Reference			Reference			Reference
	Closed	0.75	0.51-1.10	0.14	0.78	0.48-1.25	0.31	0.67	0.29-1.53	0.34

OS: Overall survival; HR: Hazards ratio; ASA: American Society of Anesthesiology; CRS: Cytoreductive surgery; HIPEC: Hyperthermic intraperitoneal chemotherapy; PCI: Peritoneal carcinomatosis index; CC: Completeness of cytoreduction.