(When we are trying to determine the line of differentiation of a tumour,
we not uncommonly are forced to rely on very limited immunoreactivity
as the best available evidence. This is not appropriate when evaluating
specific cytokeratins. It is important to know the thresholds for positivity,
which vary between papers, in some cases the threshold being set as low
as 1% of cells1,7, often at 10% of cells, but at the
most stringent requiring at least 50% of cells to show at least moderate
staining2.)
Predominantly
CK7+/CK20- |
|
CK7+/CK20+ |
CK7+/CK20- |
CK7-/CK20+ |
CK7-/CK20- |
Lung,
adenocarcinoma |
14% (6/541, 6/74(Tumours
were considered positive if at least 10% of cells showed at least
moderate immunoreactivity.)2,
2/155, 2/438,
1/1010, 1/2122, 18/4224) |
76% (39/541, 64/74(Tumours
were considered positive if at least 10% of cells showed at least
moderate immunoreactivity.)2,
12/155, 16/17(signet
ring cell carcinomas)6,
41/438, 9/1010, 20/2122,
14/16(using
cell blocks)23,
24/4224, 30/4025) |
0/541, 0/74(Tumours
were considered positive if at least 10% of cells showed at least
moderate immunoreactivity.)2,
0/155, 0/1010 |
10% (9/541, 4/74((Tumours
were considered positive if at least 10% of cells showed at least
moderate immunoreactivity.))2,
1/155, 0/1010,
2/16(using
cell blocks)23,
10/4025) |
Lung,
bronchoalveolar |
0/31, 8/28(7
mucinous and 1 mixed)8 |
3/31, 20/28(1
mucinous, 4 mixed and 15 non-mucinous)8 |
0/31 |
0/31 |
Malignant
mesothelioma |
0/161, 0/1710 |
11/161, 11/1710 |
0/161, 0/1710 |
5/161, 6/1710 |
Breast, infiltrating
ductal |
6/381, 0/2010 |
31/381, 19/2010,
6/6(tumour
type not specified)22,
6/1225 |
1/381, 0/2010 |
0/381, 1/2010,
6/1225 |
Breast,
infiltrating lobular |
1/111, 0/610 |
10/111, 6/610 |
0/111, 0/610 |
0/111, 0/610 |
Thyroid
neoplasms |
0/55(24
were adenomas, 16 were medullary carcinomas, five were follicular
carcinomas, and 10 were papillary carcinomas)10 |
54/55(24
were adenomas, 16 were medullary carcinomas, five were follicular
carcinomas, and 10 were papillary carcinomas)10,
49/59(adenomas:
6/6 follicular and 6/6 oncocytic. carcinomas: 3/4 follicular,
8/8 papillary, 6/7 poorly differentiated, 4/6 Hurtle cell, 1/2
medullary, 0/4 anaplastic and 15/16 metastatic carcinomas)12 |
0/55(24
were adenomas, 16 were medullary carcinomas, five were follicular
carcinomas, and 10 were papillary carcinomas)10 |
1/55(24
were adenomas, 16 were medullary carcinomas, five were follicular
carcinomas, and 10 were papillary carcinomas)10,
10/59(adenomas:
0/6 follicular and 0/6 oncocytic. carcinomas: 1/4 follicular,
0/8 papillary, 1/7 poorly differentiated, 2/6 Hurtle cell, 1/2
medullary, 4/4 anaplastic and 1/16 metastatic carcinomas)12
|
Salivary
gland |
0/9(five
were mixed tumors, two were Warthins tumors, and two were mucoepidermoid
carcinomas)10,
0/ 15319, 6/8420 |
9/9(five
were mixed tumors, two were Warthins tumors, and two were mucoepidermoid
carcinomas)10,
153/15319, 78/8420 |
0/9(five
were mixed tumors, two were Warthins tumors, and two were mucoepidermoid
carcinomas)10,
0/15319, 0/8420 |
0/9(five
were mixed tumors, two were Warthins tumors, and two were mucoepidermoid
carcinomas)10,
0/15319, 0/8420 |
Thymoma |
0/810, 0/3414 |
0/810, 28/3414 |
0/810, 0/3414 |
8/810, 6/3414 |
Oesophageal adenocarcinoma |
1/30(Tumours
were considered positive if at least 50% of cells showed at least
moderate immunoreactivity.)3,
11/11(oesophagus
and oesophago-gastric junction)7 |
27/30(Tumours
were considered positive if at least 50% of cells showed at least
moderate immunoreactivity.)3,
0/11(oesophagus
and oesophago-gastric junction)7 |
1/30(Tumours
were considered positive if at least 50% of cells showed at least
moderate immunoreactivity.)3,
0/11(oesophagus
and oesophago-gastric junction)7 |
1/30(Tumours
were considered positive if at least 50% of cells showed at least
moderate immunoreactivity.)3,
0/11(oesophagus
and oesophago-gastric junction)7 |
Ovarian
serous and endometrioid |
0/191, 1/24(12
were serous papillary, four were clear cell, and eight were endometrioid)10, 2/11(endometrioid
carcinomas: CK20 focally positive)15 |
19/191, 23/24(12
were serous papillary, four were clear cell, and eight were endometrioid)10, 9/11(endometrioid
carcinomas)15 |
0/191, 0/24(12
were serous papillary, four were clear cell, and eight were endometrioid)10, 0/11(endometrioid
carcinomas)15 |
0/191, 0/24(12
were serous papillary, four were clear cell, and eight were endometrioid)10, 0/11(endometrioid
carcinomas)15 |
Endometrial |
3/251, 0/1010 |
20/251, 10/1010 |
0/251, 0/1010 |
2/251, 0/1010 |
Cervix, squamous cell carcinoma |
0/1510 |
13/1510 |
0/1510 |
2/1510 |
Predominantly
CK7-/CK20+ |
|
CK7+/CK20+ |
CK7+/CK20- |
CK7-/CK20+ |
CK7-/CK20- |
Appendiceal adenocarcinoma |
1/7(well
differentiated)7,
8/23(These
adenocarcinomas were metastatic to the ovary and included seven
signet ring cell carcinoma of appendix: also 4 of 31 low grade
adenomatous mucinous tumours)18 |
0/77, 0
/23(These
adenocarcinomas were metastatic to the ovary and included seven
signet ring cell carcinoma of appendix: also 0 of 31 low grade
adenomatous mucinous tumours)18 |
6/7(well
differentiated)7,
15
/23(These
adenocarcinomas were metastatic to the ovary and included seven
signet ring cell carcinoma of appendix: also 27 of 31 low grade
adenomatous mucinous tumours)18 |
0/77, 0
/23(These
adenocarcinomas were metastatic to the ovary and included seven
signet ring cell carcinoma of appendix: also 0 of 31 low grade
adenomatous mucinous tumours)18 |
Appendiceal goblet cell carcinoid |
1/97, 4/6(appendiceal
mixed goblet cell carcinoid / adenocarcinoma)7 |
0/97, 0/6(appendiceal
mixed goblet cell carcinoid / adenocarcinoma)7 |
8/97, 2/6(appendiceal
mixed goblet cell carcinoid / adenocarcinoma)7 |
0/97, 0/6(appendiceal
mixed goblet cell carcinoid / adenocarcinoma)7 |
Colorectal adenocarcinoma (non-mucinous
and mucinous): note that CK7
positivity may be more common in rectal carcinomas. |
5/511, ,
4/29(2
well/moderately differentiated and 2 poorly differentiated)7, 4/30(colorectal
adenocarcinoma metastatic to lung)8,
1/2010, 12/225(Low
grade 5/158, high grade 7/67 . Study used tissue arrays.)16, 0/11(Metastases
to ovary . Study used tissue arrays.)16, 1/24(only
focal expression of CK7)17,
3/28(These
tumours were metastatic to the ovary and included one signet ring
cell carcinoma of colorectum; all 3 were focally CK7+ and diffusely
CK20+)18, 1/1224, 1/1425 |
0/511,
,
1/29(poorly
differentiated)7,
1/30(colorectal
adenocarcinoma metastatic to lung)8,
0/2010, 9/225(Low
grade 3/158, high grade 6/67 . Study used tissue arrays.)16, 0/11(Metastases
to ovary . Study used tissue arrays.)16,
0/28(These
tumours were metastatic to the ovary and included one signet ring
cell carcinoma of colorectum)18
|
40/511, ,
23/29(19
well/moderately differentiated and 4 poorly differentiated)7, 25/30(colorectal
adenocarcinoma metastatic to lung)8,
19/2010, 3/3(metastatic
to ovary)15,
153/225(Low
grade 118/158, high grade 35/67 . Study used tissue arrays.)16, 10/11(Metastases
to ovary . Study used tissue arrays.)16, 22/2417, 23/28(These
tumours were metastatic to the ovary and included one signet ring
cell carcinoma of colorectum; 17 were diffusely CK20+, 6 were
focally CK20+)18,
11/1224, 11/1425 |
6/511,
,
1/29(poorly
differentiated)7,
0/2010, 51/225(Low
grade 32/158, high grade 19/67 . Study used tissue arrays.)16, 1/11(Metastases
to ovary . Study used tissue arrays.)16, 1/2417, 2/28(These
tumours were metastatic to the ovary and included one signet ring
cell carcinoma of colorectum)18,
2/1425
|
Merkel
cell carcinoma |
0/910 |
0/910 |
7/910 |
2/910 |
Predominantly
CK7+/CK20+ |
|
CK7+/CK20+ |
CK7+/CK20- |
CK7-/CK20+ |
CK7-/CK20- |
Small
intestinal adenocarcinoma |
16/2417 |
8/2417 |
0/2417 |
0/2417 |
Ovarian
mucinous |
14/151, 10/18(invasive
tumours[CK7 diffuse / CK20 focal; 4, CK7 diffuse / CK20 diffuse;
6]: also 29 of 35 borderline tumours [CK7 diffuse / CK20 focal;
14, CK7 focal / CK20 focal; 4, CK7 diffuse / CK20 diffuse; 10,
CK7 focal / CK20 diffuse; 1])18 |
1/151, 8/18(invasive
tumours[all diffusely CK7+]: also 4 of 35 borderline tumours[
CK7 diffuse; 3, focal 1])18 |
0/151, 0/18(invasive
tumours: also 2 of 35 borderline tumours[CK20 diffuse; 1, focal;
1])18 |
0/151,
0/18(invasive
tumours: also 0 of 35 borderline tumours)18
|
Endocervical adenocarcinoma |
7/818 |
1/818 |
0/818 |
0/818 |
Bladder, transitional cell carcinoma |
17/191, 12/264,
17/289, 6/24(well
differentiated transitional cell carcinomas were more likely to
be CK 20 positive)10 |
2/191, 12/264,
6/289, 15/2410 |
0/191, 1/289,
1/2410 |
0/191, 4/289,
2/2410 |
Cholangiocarcinoma |
31/4813, 6/1410,
3/418, 5/14(intrahepatic
cholangiocarcinoma metastatic to ovary; all cases showed diffuse
staining for CK7 while only two cases showed diffuse positivity
for CK20 and in only one case was it as strong as the CK7)21 |
15/4813, 7/1410,
0/418, 9/14(intrahepatic
cholangiocarcinoma metastatic to ovary; 7 cases showed diffuse
staining for CK7 and two cases only focal staining for CK7)21 |
2/4813, 0/1410,
1/418 |
0/4813, 1/1410,
0/418 |
Pancreatic adenocarcinoma |
15/231, 8/1310,
11/14(These
tumours were metastatic to the ovary )18 |
6/231, 4/1310,
3/14(These
tumours were metastatic to the ovary )18 |
2/231, 0/1310,
0/14(These
tumours were metastatic to the ovary )18 |
0/231, 1/1310,
0/14(These
tumours were metastatic to the ovary )18 |
Predominantly
CK7-/CK20- |
|
CK7+/CK20+ |
CK7+/CK20- |
CK7-/CK20+ |
CK7-/CK20- |
Head and neck, squamous cell carcinoma |
0/3010 |
8/3010 |
2/3010 |
20/3010 |
Lung,
squamous cell |
0/121, 0/1510 |
0/121, 7/15(this
figure is taken from table 3 but is contradicted by their table
1 and the text of their results. It is possible that this entry
should read "0/15")10,
7/8(using
cell blocks)23 |
1/121, 0/1510 |
11/121, 8/15(this
figure is taken from table 3 but is contradicted by their table
1 and the text of their results. It is possible that this entry
should read "15/15)10,
1/8(using
cell blocks)23 |
Lung,
small cell |
0/111, 0/710 |
2/111, 3/710,
4/5(using
cell blocks)23 |
0/111, 0/710 |
9/111, 4/710,
1/5(using
cell blocks)23 |
Lung,
carcinoid |
0/910, 0/1611 |
2/910, 9/1611 |
0/910, 0/1611 |
7/910, 7/1611 |
Oesophagus, squamous cell carcinoma |
0/1410 |
3/1410 |
0/1410 |
11/1410 |
Gastrointestinal
carcinoid |
0/1510 |
2/1510 |
1/1510 |
12/1510 |
Colonic high grade neuroendocrine
carcinoma |
0/57 |
0/57 |
0/57 |
5/5(2
small cell carcinomas, 2 large cell neuroendocrine carcinomas,
1 mixed small cell / large cell neuroendocrine carcinoma)7 |
Hepatocellular
carcinoma |
2/301, 0/1110 |
5/301, 1/1110 |
0/301, 1/1110 |
23/301, 9/1110 |
Renal
cell carcinoma |
0/171, 0/1910 |
4/171, 2/1910 |
1/171, 0/1910 |
12/171, 17/1910 |
Prostatic
adenocarcinoma |
1/131, 1/599,
0/1810 |
1/131, 5/599,
0/1810 |
3/131, 5/599,
0/1810 |
8/131, 48/599,
18/1810 |
Germ cell tumour |
0/14(six
were embryonal carcinomas, four were seminomas, three were teratomas,
and one was a yolk sac tumor)10 |
1/14(six
were embryonal carcinomas, four were seminomas, three were teratomas,
and one was a yolk sac tumor)10 |
0/14(six
were embryonal carcinomas, four were seminomas, three were teratomas,
and one was a yolk sac tumor)10 |
13/14(six
were embryonal carcinomas, four were seminomas, three were teratomas,
and one was a yolk sac tumor)10 |
Epithelioid
sarcoma |
0/1210 |
0/1210 |
0/1210 |
12/1210 |
Adrenal
cortical tumour |
0/1010 |
0/1010 |
0/1010 |
10/1010 |
Variable |
|
CK7+/CK20+ |
CK7+/CK20- |
CK7-/CK20+ |
CK7-/CK20- |
Gastric adenocarcinoma |
11/291, 5/14(Tumours
were considered positive if at least 50% of cells showed at least
moderate immunoreactivity.)3,
27/38(5
well/moderately differentiated and 22 poorly differentiated)7, 1/810,
75/289(Intestinal
type 26/112, diffuse type 49/177 . Study used tissue arrays.)16, 16/43(Metastases
to ovary . Study used tissue arrays.)16,
4/518 |
5/291,
3/14(Tumours
were considered positive if at least 50% of cells showed at least
moderate immunoreactivity.)3,
8/38(3
well/moderately differentiated and 5 poorly differentiated)7, 2/810,
132/289(Intestinal
type 52/112, diffuse type 80/177 . Study used tissue arrays.)16, 18/43(Metastases
to ovary . Study used tissue arrays.)16,
0/518
|
10/291,
3/14(Tumours
were considered positive if at least 50% of cells showed at least
moderate immunoreactivity.)3,
3/38(all
3 poorly differentiated)7,
3/810, 42/289(Intestinal
type 19/112, diffuse type 23/177 . Study used tissue arrays.)16, 8/43(Metastases
to ovary . Study used tissue arrays.)16,
1/518
|
3/291,
3/14(Tumours were considered
positive if at least 50% of cells showed at least moderate immunoreactivity.)3, 0/387,
2/810, 40/289(Intestinal
type 15/112, diffuse type 25/177 . Study used tissue arrays.)16, 1/43(Metastases
to ovary . Study used tissue arrays.)16,
0/518
|
One must note that the cut-off percentage of staining for a positive
result is varies in different studies from 1%1 to 5%10, which in part may contribute to
differences in the results in some groups of carcinomas between studies.
In addition, the CK 20 monoclonal antibody that was used varied (American
Research Products [APR], Inc., Belmont, MA10, DAKO1).