Survival difference between mucinous vs. non-mucinous colorectal cancer following cytoreductive surgery and intraperitoneal chemotherapy

Figures & data

Table 1. Patient characteristics.

	Non-Mucinous CRC (NMC)	Mucinous CRC (MC)	p
Total n = 311 (%)	213 (69.6)	93 (30.4)
Sex, n (%)			.017
Male	81 (38.0)	49 (52.7)
Female	132 (62.0)	44 (47.3)
Age mean (SD)	55.6 (13.4)	55.1 (13.7)	.776
PCI mean (SD)	8.1 (5.2)	12.9 (7.8)	<.001
Presence of liver metastases n (%)	59 (27.1)	8 (8.6)	<.001
Primary lymph node involvement n (%)	143 (71.1)	66 (75.0)	.500
HIPEC n (%)	184 (86.4)	88 (94.6)	.035
EPIC n (%)	56 (26.4)	23 (24.7)	.757
Site of primary tumor n (%)			.322
Right colon	76 (36.9)	44 (47.8)
Left colon	22 (10.7)	9 (9.8)
Transverse colon	14 (6.8)	9 (9.8)
Rectum	23 (11.2)	7 (7.6)
Rectosigmoid	13 (6.3)	6 (6.5)
Sigmoid	58 (28.2)	17 (18.5)
Preoperative chemotherapy n (%)	161 (75.9)	69 (74.2)	.744
Grade n (%)			<.001
No malignancy	29 (15.5)	3 (3.8)
Well differentiated	2 (1.1)	4 (5.0)
Moderately differentiated	119 (63.6)	45 (56.2)
Poorly differentiated	34 (18.2)	7 (8.8)
Signet cell	3 (1.6)	21 (26.2)

Table 2. Perioperative mortality and morbidity and survival outcomes.

	Non-mucinous CRC	Mucinous CRC	p
Hospital mortality (%)	2 (0.9)	0 (0)	.347
Major morbidity (Grade III/IV) n (%)	69 (32.5)	31 (34.4)	.750
ICU stay mean (SD)	2.6 (2.8)	4.4 (11.5)	.037
HDU stay mean (SD)	2.1 (3.7)	2.2 (5.0)	.820
Total stay mean (SD)	21.2 (17.4)	26.8 (28.7)	.037

Figure 1. OS between MC and NMC.

Figure 2. DFS between MC and NMC.

Figure 3. Subgroup analysis: liver metastases in patients with NMC.

Figure 4. Subgroup analysis: liver metastases in patients with MC.

Table 3. Survival outcomes.

	Non-mucinous CRC	Mucinous CRC	p
Overall OS median (months) (95% CI)	38.1 (31.1–45.0)	32.6 (21.3–44.0)	.657
1-year OS (%)	87.9	90.4
3-year OS (%)	54.5	43.9
5-year OS (%)	35.2	29.4
DFS median (months) (95% CI)	13.1 (11.5–14.8)	2.3 (7.7–16.7)	.938
1-year DFS (%)	55.6	51.8
3-year DFS (%)	11.0	14.3
5-year DFS (%)	0.6	3.6
Subgroup analysis – Median OS (months) (95% CI)
Right colon	43.3 (30.7–55.9)	39.2 (18.4–60.0)	.863
Left colon	102.8 (–)	24.9 (0–54.0)	.551
Transverse colon	59.8 (3.7–116.0)	44.9 (0–98.4)	.277
Rectum	72.8 (–)	18.5 (15.1–22.0)	.178
Rectosigmoid	30.7 (17.1–44.3)	40.9 (–)	.156
Sigmoid	37.8 (22.0–53.7)	24.6 (11.9–37.4)	.814

Table 4. Univariate and multivariate analysis of prognostic factors for OS.

	Univariate (HR, 95%CI)	p	Multivariate (HR, 95%CI)	p
MC	0.92 (0.64–1.32)	.657	1.41 (0.84–2.36)	.190
PCI	1.07 (1.05–1.10)	<.001	1.07 (1.04–1.11)	<.001
Presence of liver metastasis	1.12 (0.770–1.64)	.562	0.84 (0.49–1.47)	.546
Involvement of lymph node	1.51 (1.02–2.23)	.040	1.26 (0.79–2.00)	.338
HIPEC	0.63 (0.42–0.95)	.029	0.62 (0.34–1.14)	.126
Age			1.00 (0.98–1.01)	.723
Tumor grade	1.48 (1.22–1.79)	<.001	1.40 (1.12–1.76)	.004
Preoperative chemotherapy	1.40 (0.94–2.08)	.100	1.65 (1.06–2.56)	.025
Site of primary tumor	1.09 (1.00–1.19)	.059	1.13 (1.02–1.26)	.025