Colorectal cancer of the young displays distinct features of aggressive tumor biology: A single-center cohort study

Table 1 Study cohort

Demographic factors	CRC patients < 50 yr of age, n (%)	CRC patients ≥ 50 yr of age, n (%)	P value
Total number (%)	70 (17)	341 (83)	-
Gender
Male	44 (62.9)	209 (61.3)	0.89
Female	26 (37.1)	132 (38.7)
BMI (kg/m2)
Median (IQR)	24.7 (22.9-27)	25 (22.4-28.9)	0.3
NA	7	24
Obesity (BMI > 30kg/m2)	7 (10)	60 (21.3)	0.154
Inflammatory bowel disease1	3 (4.2)	6 (1.8)	0.19
Hereditary CRC Syndrome2	5 (7.1)	7 (2.1)	0.04a
Neoadjuvant Treatment	17 (24.3)	65 (19.1)	0.33
ASA Class
I	7 (11.3)	9 (2.9)	< 0.01b
II	43 (69.4)	182 (58.9)
III	9 (14.5)	110 (35.6)
IV	3 (4.8)	8 (2.6)
NA	8	32
High-risk drinking3
Yes	3 (4.8)	48 (15.4)	0.03a
No	60 (95.2)	267 (84.8)
NA	7	26
Current smoker			0.52
Yes	18 (28.6)	76 (24.1)
No	45 (71.4)	239 (75.9)
NA	7	26
Preoperative albumine level (g/L)
Median (IQR)	41.5 (37.3-45)	38.5 (33-42)	< 0.01b
NA	32	159

¹Crohn’s disease and ulcerative colitis.

²Lynch syndrome, familial adenomatous polyposis, MUTYH associated polyposis.

³High-risk drinking is the consumption of 4 or more drinks on any day or 8 or more drinks per week for women and 5 or more drinks on any day or 15 or more drinks per week for men[15].

NA: Data not available, significant difference between age groups (^aP < 0.05, ^bP < 0.01). CRC: Colorectal cancer; BMI: Body mass index; ASA: American Society of Anesthesiologist.

Table 2 Tumor characteristics and histopathological features

Tumor characteristics & histopathologic features	CRC patients < 50 yr of age, n (%)	CRC patients ≥ 50 yr of age, n (%)	P value
Tumor location
Colon	42 (60)	217 (63.6)	0.58
Rectum	28 (40)	124 (36.4)
Right sided	21 (30.4)	92 (27.1)	0.74
Left sided (incl. rectum)	47 (68.1)	233 (68.7)
Transverse colon	1 (1.5)	6 (1.8)
Multiple locations	- (-)	8 (2.36)
UICC Tumor Stage
I	12 (17.1)	75 (22.1)	0.04a
II	10 (14.3)	91 (26.8)
III	21 (30)	83 (24.4)
IV	27 (38.6)	91 (26.8)
T-Status
T1	7 (10.6)	48 (14.7)	< 0.01b
T2	11 (16.7)	45 (13.8)
T3	24 (36.4)	176 (53.8)
T4	24 (36.4)	58 (17.7)
NA	4	14
Lymph node metastasis
N0	26 (38.2)	184 (57.1)	< 0.01b
N1	20 (29.4)	86 (26.7)
N2	22 (32.4)	52 (16.2)
NA	2	19
M-Status
M0	43 (61.4)	238 (72.1)	0.08
M1	27 (38.6)	92 (27.9)
NA	-	11
Vascular invasion
V0	22 (64.7)	116 (65.9)	1
V1	12 (35.3)	60 (34.1)
NA	36	165
Lymphatic invasion
L0	14 (38.9)	116 (65.9)	0.04a
L1	22 (61.1)	60 (34.1)
NA	36	155
Histological grading
G1	2 (4.4)	10 (4.1)	0.03a
G2	25 (55.6)	181 (73.6)
G3	18 (40)	55 (22.7)
NA	25	95
Histological type
Intestinal type	53 (76.8)	276 (82.1)	0.12
Signet ring cell type	6 (8.7)	11 (3.3)
Mucinous type	10 (14.5)	49 (14.6)
NA	1	5
Stoma
Yes	30 (46.9)	163 (51.9)	0.49
No	34 (53.1)	151 (48.1)
NA	6	27
Lymph nodes removed
mean ± SD	27.5 (17.1)	20.1 (15.8)	0.03a
Median (IQR)	22 (15-33.8)	18 (14-25)
NA	8	36
Lymph nodes positive
mean ± SD	5 (10.1)	1.61 (3.2)	0.01a
Median (IQR)	2 (0-5)	0 (0-2)
NA	8	36
Lymph node ratio
mean ± SD	0.1654	0.0817	< 0.01b
Reoperation within 30 d
Yes	5 (7.5)	23 (7.2)	1
No	59 (92.5)	291 (91.8)
NA	-	3

NA: Data not available, significant difference between age groups (^aP < 0.05, ^bP < 0.01). CRC: Colorectal cancer; UICC: Union for International Cancer Control.

Table 3 Immunohistochemical and molecular phenotypes

Molecular or immunohistochemical feature	CRC patients < 50 yr of age, n (%)	CRC patients ≥ 50 yr of age, n (%)	P value
Microsatellite stability
Stable	56 (91.8)	213 (84.9)	0.21
Unstabile	5 (8.2)	38 (15.1)
NA	9	90
KRAS mutation
Negative	23 (65.7)	48 (51.1)	0.17
Positive	12 (34.3)	46 (48.9)
NA	35	247
NRAS mutation
Negative	27 (90)	74 (94.9)	0.39
Positive	3 (10)	4 (5.1)
NA	40	263
BRAF mutation
Negative	29 (90.6)	87 (86.1)	0.76
Positive	3 (9.4)	14 (13.9)
NA	38	240
HER 2
Negative	8 (80)	24 (70.6)	0.70
Positive	2 (20)	10 (29.4)
NA	60	307

CRC: Colorectal cancer; NA: Not available.