Comparison between colorectal low- and high-grade mucinous adenocarcinoma with MUC1 and MUC5AC

Table 1 Clinical and immunohistochemical characteristics

Case	Location	Sex	Age	Grade	MUC1/DF3	MUC1/CORE	MUC2	MUC5AC/CHL2	HGM	MUC6	CD10	CDX2
1	T	F	71	Low	-	-	++	+	+	-	-	-
2	R	M	71	Low	-	-	++	++	+	-	-	++
3	A	F	83	Low	+	-	++	++	++	-	-	++
4	A	F	90	Low	+	+	++	++	+	-	-	++
5	R	F	48	Low	+	-	++	+	++	-	-	++
6	R	M	44	Low	-	-	++	+	-	-	-	++
7	R	F	75	High	++	++	++	+	+	-	-	-
8	T	F	57	High	++	+	++	-	+	-	-	++
9	R	M	47	High	++	+	+	-	-	-	-	+
10	R	M	63	High	+	-	++	+	+	-	-	++
11	A	M	57	High	+	-	++	-	-	-	-	-
12	A	F	68	High	+	+	++	-	-	-	-	++
13	T	F	48	High	++	+	+	+	++	-	-	+
14	R	F	75	High	++	+	++	-	+	-	-	-
15	R	M	48	High	++	+	+	-	-	-	-	+
16	A	F	48	High	+	-	++	+	+	-	-	++

T: Transverse colon; R: Rectum; A: Ascending colon; F: Female; M: Male. Immunohistochemical stains were graded by the presence of positively stained tumor cells as follow: -, less than 5% of tumor cells; +, 5% to 50% of tumor cells; and ++, over 50% of tumor cells.

Table 2 Summary of immunostaining

Antibodies	Low-grade MAC (%)	High-grade MAC (%)
MUC1/DF31	3/6 (50)	10/10 (100)
MUC1/CORE	1/6 (16.7)	7/10 (70)
MUC2	6/6 (100)	10/10 (100)
MUC5AC/CHL21	6/6 (100)	4/10 (40)
HGM	5/6 (83.3)	6/10 (60)
MUC6	0/6 (0)	0/10 (0)
CD10	0/6 (0)	0/10 (0)
CDX2	5/6 (83.3)	7/10 (70)

Proportions (%) of cases evaluated as “positive” are shown. Statistical analysis between low- and high-grade MAC was carried out by χ² test.

¹A P-value below 0.05 was considered significant. MAC: Mucinous adenocarcinoma.