Colorectal carcinomas in MUTYH-associated polyposis display histopathological similarities to microsatellite unstable carcinomas

Table 4 Results of somatic mutation analysis and IHC analysis

Tumour nr	APC (MCR) mutation*	KRAS mutation	p53 IHC†	p53 mutation*	17P LOH ^@	Beta-catenin IHC††	SMAD4 mutation*	MSI ^c	MLH1-PMS2 IHC**
1	no	c.34G>T	++	No	yes	0	c.227G>GT, p.R76RI	S	+
2	no	c.34G>T	+++	c.758C>CT, p.T253TI*	yes	0	no	S	+
3	no	no	+++		yes	0		S	+
4	no	c.34G>T	+		no	0	c.1058A>AG, p.Y353YC* c.1096C>CT, p.Q366QX	S	+
5	no	c.34G>T	+	c.593A>AT, p.E198EV	no	0	c.161T>TC, p.L54LS c.740G>GA, p.G247GE c.1597C>CT, p.L533LF	S	+
7	c.3949G>GT p. E1317EX* c.4339C>CT p. Q1447QX*	no	+	c.565G>GA, p.A189AT* c.599A>AG, p.N200NS*	yes	0/+	no	S	+
8	no	c.34G>T	+	c.446C>CT, p.S149SF*	no	0	no	S	+
11	no	no	0			0		S	+
12	no	no	+			0		S	+
13	no	c.34G>T	0			+/++		L~	heterogenous
14	no	no		No	no		no	S	+
16	no	c.34G>T	+	c.446C>CT, p.S149SF*	no	+	c.115G>GA, p.A39AT c.74G>GA, p.C25CY	S	+
17	no	c.34G>T	+++		no	0	c.1609G>GT, p.D537DY*		+
18	no	no	+			0		S
20	no	c.34G>T	+			0/+		S	+
21	c.4222G>GT p.E1408EX*	no	+			0		S	+
22	c.4222G>GT p.E1408EX*	no	+	c.13791G>GT, p.E271EX*	yes	0/+	no	S	+
23	no	c.34G>T	++	c.596G>GT, p.G199GV*	yes	0	no	S	+
24	no	c.34G>T	++	c.820G>GT, p.V274VF*	yes	0		S	+
28	no	c.34G>T	+	No		0	no	S	+
29	no	c.34G>T	0		yes	0/+	no	S	+
30	no	c.34G>T	+			0/+		S	+
31	c.4085C>CT p.S1362SF	no	+			++		S	+
32	no	no	+++		no	+	no	S
33	no	c.34G>T	++			0/+		S
34	no	no	+++	No	yes	0	no	S	+
35	no	c.34G>T	+	No	no	0		S	+
36	c.4381G>GT p.E1461EX	c.34G>T	+		no	0/+	no	S	+
37	no	c.34G>T	+		yes	0		S
38	no	no	+		no	0/+		S	+
39	no	c.34G>T	+			0		S	+
40	no	c.34G>T	+			0		S	+
41	no	no	++	c.13794G>GA, p.V272VM*	yes	0	no	S	+
42	no	c.34G>A	++			0	no	S	+
43	no	c.34G>T	+	no	yes	0	no	S	+
44	no	c.34G>T	++			0/+		S	+

Blank cells: not done/not ascertainable, † 0 = none, + = >0<25%, ++ = 25–75%, +++>75%, *previously reported mutations, see http://www.sanger.ac.uk/genetics/CGP/cosmic/ (SMAD4) and http://p53.free.fr/index.html (P53), ^@LOH, as reported by Middeldorp et al (mainly copy neutral LOH and not physical loss),⁸ †† 0= category 1(membranous staining), 0/+ = 2A (membranous and some nuclear staining), + = 2B (membranous & increased nuclear staining), ++ = 3 (strong nuclear & less or no membranous staining), ~2/9 markers unstable.

ISSN: 1471-2407