Calretinin

Calretinin is a calcium-binding protein and a member of the family to EF-hand proteins, to which S-100 also belongs. Its function is unknown.

Immunohistochemical expression

Normal tissues:

• central and peripheral nervous system: neurones and nerve fibres⁹

• retina

• mesothelium⁹

• the keratinising superficial layer of the pilar infundibulum⁹

• eccrine glands⁹

• the convoluted tubules of the kidneys⁹

• Leydig and Sertoli cells of testes and the epithelium of the rete testis⁹

• endometrium, stronger in the secretory phase⁹

• myometrial mast cells⁹

• ovarian surface epithelium, stromal and thecal cells, follicular cysts², corpora lutea² and the rete ovary⁹

• adrenal cortex⁹

• keratinising epithelial cells of the thymus⁹

• adipocytes⁹

Tumours:

• Mesothelioma, but less commonly in carcinoma. The antibody from Zymed, against human recombinant calretinin, appears to give superior discrimination.

	conclusion regarding usefulness	adenocarcinoma	mesothelioma
Doglioni 19969 (Polyclonal, variously Swant and Chemicon)	yes	28/294	44/44 (36 epithelioid, 5 biphasic and 3 sarcomatoid)
Gotzos 199610 (Polyclonal, non-commercial)	yes	0/4 (The only immunoreactivity was the rare weak staining of vacuolated cells.)	22/23 (Immunoreactivity was seen in epithelial mesotheliomas (7/7) and in the epithelial component of mixed mesotheliomas(15/15). The one negative case appears to have been a purely sarcomatoid mesothelioma.)
Riera 199713 (Polyclonal, Chemicon)	no	13/221	24/57
Ordonez 199814 (Polyclonal, Zymed)	yes	14/155 (3/38 pulmonary, 5/38 ovarian, 2/15 endometrial, 2/23 breast, 2/16 colonic, 0/8 renal, 0/8 prostatic, 0/6 thyroid, 0/3 pancreatic)	38/38
Leers 199815 (Polyclonal, Swant)	yes	1/21 (one case showed positivity of less than 10% of cells)	20/20 (17 cases showed positivity of more than 10% of cells, 3 cases showed positivity of less than 10% of cells)
Cury 20008 (Polyclonal, Zymed)	yes	1/59 (One case showed nuclear staining. lung = 19; breast = 21; ovary = 6; colon = 10; kidney = 4; uterus, epididymis, pancreas = 1 case each)	47/51 (all epithelioid mesotheliomas)
Brockstedt 20004 (Polyclonal, Zymed)	yes	16/57	110/119 (Staining is described as "nuclear and cytoplasmic".)
Oates 200024 (Polyclonal, Chemicon)	no	28/40	25/26
Kayser 20015 (Polyclonal, Dako)	yes	20/146 (9/82 lung, 8/47 breast, 0/3 colon, 1/2 kidney, 2/12 site not known)	97/118 (84/99 epithelioid, 9/12 mixed and 4/7 sarcomatoid)
Carella 20017 (Polyclonal, Chemicon)	yes	2/20	40/46 (The staining is stated to be "finely granular and cytoplasmic. and the nuclei always remained unstained.")
Comin 200112 (Polyclonal, Swant)	yes	2/23	42/42
Miettinin 200129 (Polyclonal, Zymed)		not studied	30/30 (123 epithelioid, 7 sarcomatous mesotheliomas)
Foster 200125 (Polyclonal, Chemicon)	no	35/51 (lung adenocarcinomas: greater tahn 50% staining in 23 cases)	35/67 (greater than 50% staining in 30 cases)
Foster 200125 (Polyclonal, Zymed)	?	9/15	3/15
Roberts 200126 (Polyclonal, Chemicon)	no	8/18	44/112
Tot 200127 (Polyclonal, Zymed)	yes	0/37 (various sites of origin)	13/14
Miettinin 200321		31/255 (17/148 acinar type, differentiated, 8/48 acinar type, solid, poorly differentiated , mucin-positive, 0/13 bronchoalveolar, 3/22 acinar type with focal neuroendocrine differentiation, 3/18 adenocarcinoma, neuroendocrine)	27/28 (10 of 10 tubulopapillary, 6 of 6 combined tubulopapillary and poorly differentiated and 11 of 12 poorly differentiated solid epithelial tumours)
Abutaily 20023 (Polyclonal, Zymed)	yes	2/35 (cytoplasmic and nuclear)	33/41 (positivity seen in 11/11 epithelioid, 20/23 mixed and 2/7 sarcomatoid mesotheliomas)
Ordonez 200328 (Polyclonal, Zymed)	yes	4/50 (lung adenocarcinomas, in 2 cases <1% of cells stained, in 2 cases, 1-25% of cells stained)	60/60 (epithelioid mesotheliomas: in 45 cases >75% of cells stained, in 15 cases 50-75% of cells stained)
Overall	YES	14% (204/1486)	80% (751/936)

A systematic review of seventeen studies (consisting of 885 epithelioid mesotheliomas and 912 pulmonary adenocarcinomas) reported sensitivities and specificities of calretinin for epithelioid mesothelioma of 82% and 85%³⁹.

There are some controversy as to whether there is nuclear as well as cytoplasmic staining in mesothelioma, and which component is diagnostically reliable. Staining is reportedly weaker in post mortem specimens that in the corresponding ante mortem specimens from the same patients¹⁹.

Similar studies have been done on cytological material:

	conclusion regarding usefulness	adenocarcinoma	mesothelioma
Barberis 199730 (Polyclonal, Swant)	yes	3/13 (various sites of origin)	8/8
Simsir 199931 (Polyclonal, Chemicon)	no	9/29 (various sites of origin)	15/26
Chhieng 200032 (Polyclonal, Zymed)	yes	0/21 (various sites of origin)	14/16
Wieczorek 200033 (Polyclonal, Zymed)	yes	3/39 (various sites of origin)	26/29
Davidson 200134 (Polyclonal, Swant)	yes	3/98 (various sites of origin)	11/12
Simsir 200135 (Polyclonal, Zymed)	yes	2/15 (sites of origin not stated)	15/17
Overall	YES	9% (20/215)	82% (89/108)

Most studies have been of mesothelioma versus pulmonary adenocarcinoma. Some metastatic carcinomas, such as renal cell carcinoma, pose particular problems.

Calretinin positivity appears to be more common in colonic carcinomas, particularly those that are poorly differentiated. Based on a total of 82 cases:

well-differentiated	5% of cases20
moderately differentiated	20% of cases20
poorly differentiated	67% of cases20
overall	22/5% of cases20

Most studies compare mesothelioma with pulmonary adenocarcinoma. There are relatively few studies breaking down adenocarcinomas by subtype, or of other types of pulmonary tumour. Where positive, staining is typically both nuclear and cytoplasmic.

adenocarcinoma	acinar type, differentiated	17/148 (9 cases showing >10% of tumour cells positive, 8 cases showing less than 10% of tumour cells positive.)21
	acinar type, solid, poorly-differentiated, mucin-positive	8/48 (5 cases showing >10% of tumour cells positive, 3 cases showing less than 10% of tumour cells positive)21
	bronchoalveolar, mucinous	0/6 21
	bronchoalveolar, non-mucinous	0/7 21
	acinar with focal neuroendocrine differentiation	3/22 (1 case showing >10% of tumour cells positive, 2 cases showing less than 10% of tumour cells positive) 21
	neuroendocrine	3/18 (All 3 cases showing less than 10% of tumour cells positive) 21
	clear cell	0/6 21
large cell	NOS	45/120 (36 cases showing more than 10% of tumour cells positive, 9 cases showing less than 10% of tumour cells positive) 21, 0/814
	with focal neuroendocrine differentiation	1/10 (less than 10% of tumour cells positive) 21
	neuroendocrine carcinoma	15/33 (8 cases showing more than 10% of tumour cells positive, 7 cases showing less than 10% of tumour cells positive) 21
small cell carcinoma		20/41 (15 cases showing more than 10% of tumour cells positive, 5 cases showing less than 10% of tumour cells positive.) 21
squamous cell	keratinising	21/62 (4 cases showing more than 10% of tumour cells positive, 17 cases showing less than 10% of tumour cells positive.) 21
	non-keratinising	19/62 (10 cases showing more than 10% of tumour cells positive, 10 cases showing less than 10% of tumour cells positive) 21
	NOS	11/2814
sarcomatoid carcinoma, spindle cell		1/6 (showing less than 10% of tumour cells positive) 21
giant cell carcinoma		4/6 (All 4 cases showing more than 10% of tumour cells positive) 21

• Adenomatoid tumours⁹

• Ameloblastoma

• Papillary carcinoma of the thymus

• Ovarian sex cord stroma tumours are reliably positive, the exception being a fibrothecoma². Other tumours which enter the differential diagnosis may sometimes be positive². Calretinin is more sensitive but less specific than inhibin.

adult granulosa cell tumour	13/13 diffuse strong; 9, diffuse moderate;1, focal strong; 32, 35/35 in 7 cases, only luteinised cells were positive17, 6/14 used protease rather than steam for antigen retrieval18
juvenile granulosa cell tumour	4/4 all diffuse strong2, 4/417
thecoma	9/917
fibrothecoma	10/11 diffuse strong; 6, diffuse moderate;2, diffuse weak; 1, focal moderate; 12, 14/1417, 0/8 used protease rather than steam for antigen retrieval18
Leydig cell tumour	3/3 diffuse strong; 2, diffuse moderate;1, focal strong; 1 !!!2
Sertoli cell tumour	4/417
Sertoli-Leydig cell tumour	1/1 diffuse strong; 12, 13/1317, 10/1018
sex cord-stromal tumour with annular tubules	2/2 diffuse strong; 1, diffuse weak;12
gynandroblastoma	1/1 diffuse strong; 12
sclerosing stromal tumour	1/1 diffuse strong; 12, 2/217
steroid cell	3/317
sex-cord stromal tumour, unclassified	1/1 diffuse strong; 12, 3/317
sex cord-stromal tumours, overall	36/372, 87/8717
fibroma	19/2017
adenofibroma (stromal component)	6/917
fibrosarcoma	8/817
serous carcinoma	3/11 <25% of cells staining17
atypical mucinous neoplasm	6/19 <25% of cells staining17
endometrioid adenocarcinoma	2/6 diffuse strong; 1, moderate focal;12, 3/15 <25% of cells staining. Four with sex-cord-like elements all negative17
clear cell carcinoma	1/7 <25% of cells staining17
endometrial stromal neoplasm	1/7 moderate focal;12
ovarian carcinoid tumour	1/2 diffuse weak;12
Brenner tumour	3/4 focal strong; 1, focal weak; 22, 1/13 epithelial component only, 4+17
malignant mixed Mullerian tumour	0/217
ovarian leiomyomatous tumour	0/12
metastatic lobular carcinoma	1/4 focal weak; 12
lymphoma	1/5 focal weak; 12
testicular seminoma	1/4 focal weak; 12
dysgerminoma	0/717
yolk sac tumour	0/517
choriocarcinoma	0/117
embryonal carcinoma	0/117
immature teratoma	0/417
mixed germ cell tumour	0/417
desmoplastic small round cell tumour	0/22
small cell carcinoma	0/117
clear cell sarcoma	0/117
female adnexal tumour of probable Wolffian origin	91% of 25 cases16

Extra-ovarian tumours which may enter the differential of metastatic granulosa cell tumour:

gastrointestinal stromal tumours	1/3222
leiomyosarcoma	11/28 (7/20 uterine, 1/2 colon, 1/2 skin, 1/2 retroperitoneal, 1/1 urinary bladder)22
endometrial stromal sarcoma	1/15 (positivity only in one case in sex-cord like areas)22
uterine undifferentiated sarcoma	0/422

• Granular cell tumour

• Cardiac myxoma: staining is strong and diffuse, both nuclear and cytoplasmic^1.

	calretinin
primary left atrial myxoma	19/19
primary right atrial myxoma	5/5
myxoma emboli	1/1
mural thrombus	0/10
jaw myxoma	0/6
papillary fibroelastomas	0/2

• Transitional cell carcinomas of bladder are negative (0/9)¹⁴

Other stromal tumours:

	Malignant peripheral nerve sheath tumour arising from neurofibroma	2/15 (focal positivity)29
	Solitary fibrous tumour of the pleura	0/1629
	Epithelioid sarcoma	0/1629
	Leiomyosarcoma	0/2029
	GIST	0/2029
	Angiosarcoma	0/2029

Diagnostic utility

• Differentiation of epithelioid mesothelioma (positive) from adenocarcinoma (negative) . Calretinin appears to be one of the best markers. Although the rate of positivity in pulmonary adenocarcinomas is low (averaging about 10%), it appears to be more common in other primary pulmonary carcinomas, including giant cell, small cell and large cell and squamous carcinoma; when positive, it is usually focal in the latter. The pattern of staining is a combination of cytoplasmic and nuclear, as in mesotheliomas. (vide supra)

• Differentiation of reactive mesothelial cells (positive) from carcinoma (negative) in effusions.

• identification of cardiac myxoma.

• identification of ovarian sex cord stromal tumours²: it is more sensitive than inhibin but less specific, as some endometrioid carcinomas and mesonephric carcinomas are positive for calretinin. See calretinin and inhibin in ovarian tumours.

References

¹ LM Terracciano et a. Calretinin as a marker for cardiac myxoma. Am J Clin Pathol 2000;114:754-759.

² McCluggage, W. G., Maxwell, P. Immunohistochemical staining for calretinin is useful in the diagnosis of ovarian sex cord-stromal tumours. Histopathology 2001;38:403-408.

³ Abutaily, A.S., Addis, B.J. and Roche, W.R. Immunohistochemistry in the distinction between malignant mesothelioma and pulmonary adenocarcinoma: a critical evaluation of new antibodies. J Clin Pathol 2002;55:662-8.

⁴ Brockstedt U, Gulyas M, Debra K. An optimized batter of eight antibodies that can distinguish most cases of epithelial mesothelioma form adenocarcinoma. Am J Clin Pathol 2000;114:203-9.

⁵ K Kayser et al. Glyco- and immunohistochemical refinement of the differential diagnosis between mesothelioma and metastatic carcinoma and survival analysis of patients. J Pathol 2001;193:175-180.

⁷ Carella R et al. Immunohistochemical panels for differentiating epithelial malignant mesothelioma from lung adenocarcinoma. Am J Surg Pathol 2001;25:43-50.

⁸ Cury, P. M.,et al. Value of the mesothelium-associated antibodies thrombomodulin, cytokeratin 5/6, calretinin, and CD44H in distinguishing epithelioid pleural mesothelioma from adenocarcinoma metastatic to the pleura. Mod Pathol 2000;13:107-112.

⁹ Doglioni, C., Tos, A. P., Laurino, L., Iuzzolino, P., Chiarelli, C., Celio, M. R., Viale, G. Calretinin: a novel immunocytochemical marker for mesothelioma. Am J Surg Pathol 1996;20:1037-46.

¹⁰ Gotzos, V., Vogt, P., Celio, M. R. The calcium binding protein calretinin is a selective marker for malignant pleural mesotheliomas of the epithelial type [published erratum appears in Pathol Res Pract 1996 Jun;192(6):646]. Pathol Res Pract 1996;192:137-47.

¹² Comin, C. E., Novelli, L., Boddi, V., Paglierani, M., Dini, S. Calretinin, thrombomodulin, CEA, and CD15: a useful combination of immunohistochemical markers for differentiating pleural epithelial mesothelioma from peripheral pulmonary adenocarcinoma Human Pathol 2001;32:529-536.

¹³ Riera, J. R. Astengo-Osuna, C. Longmate, J. A. Battifora, H. The immunohistochemical diagnostic panel for epithelial mesothelioma: a reevaluation after heat-induced epitope retrieval. Am J Surg Path 1997;21:1409-19.

¹⁴ Ordonez, N. G. Value of calretinin immunostaining in differentiating epithelial mesothelioma from lung adenocarcinoma. Mod Pathol 1998;11:929-933.

¹⁵ Leers, M. P., Aarts, M. M., Theunissen, P. H. E-cadherin and calretinin: a useful combination of immunochemical markers for differentiation between mesothelioma and metastatic adenocarcinoma. Histopathology 1998;32:209-216.

¹⁶ Devouassoux-Shisheboran, M., Silver, S. A., Tavassoli, F. A. Wolffian adnexal tumor, so-called female adnexal tumor of probable Wolffian origin (FATWO): immunohistochemical evidence in support of a Wolffian origin. Hum Pathol 1999;30:856-63.

¹⁷ Movahedi-Lankarani, S. and Kurman, R.J. Calretinin, a more sensitive but less specific marker than alpha- inhibin for ovarian sex cord-stromal neoplasms: an immunohistochemical study of 215 cases. Am J Surg Pathol 2002;26:1477-83.

¹⁸ Cao, Q.J., Jones, J.G. and Li, M. Expression of calretinin in human ovary, testis, and ovarian sex cord- stromal tumors. Int J Gynecol Pathol 2001;20:346-52.

¹⁹ Roberts, F., McCall, A. E., Burnett, R. A. Malignant mesothelioma: a comparison of biopsy and postmortem material by light microscopy and immunohistochemistry. J Clin Pathol 2001;54:766-70.

²⁰ Gotzos, V., Wintergerst, E.S., Musy, J.P., Spichtin, H.P. and Genton, C.Y. Selective distribution of calretinin in adenocarcinomas of the human colon and adjacent tissues. Am J Surg Pathol 1999;23:701-11.

²¹ Miettinen, M. and Sarlomo-Rikala, M. Expression of calretinin, thrombomodulin, keratin 5, and mesothelin in lung carcinomas of different types: an immunohistochemical analysis of 596 tumors in comparison with epithelioid mesotheliomas of the pleura. Am J Surg Pathol 2003;27:150-8.

²² Shah, V.I., Freites, O.N., Maxwell, P. and McCluggage, W.G. Inhibin is more specific than calretinin as an immunohistochemical marker for differentiating sarcomatoid granulosa cell tumour of the ovary from other spindle cell neoplasms. J Clin Pathol 2003;56:221-4.

²⁴ Oates, J. and C. Edwards (2000). "HBME-1, MOC-31, WT1 and calretinin: an assessment of recently described markers for mesothelioma and adenocarcinoma." Histopathology 36(4): 341-7.

²⁵ Foster, M. R., J. E. Johnson, et al. (2001). "Immunohistochemical analysis of nuclear versus cytoplasmic staining of WT1 in malignant mesotheliomas and primary pulmonary adenocarcinomas." Arch Pathol Lab Med 125(10): 1316-20.

²⁶ Roberts, F., C. M. Harper, et al. (2001). "Immunohistochemical analysis still has a limited role in the diagnosis of malignant mesothelioma. A study of thirteen antibodies." Am J Clin Pathol 116(2): 253-62. (Initial publication of data as abstract ⁸Harper CM. Evaluation of a commercially available immunohistochemical diagnostic panel for malignant mesothelioma. J Pathol 2001:193(suppl):39^A.)

²⁷ Tot, T. (2001). "The value of cytokeratins 20 and 7 in discriminating metastatic adenocarcinomas from pleural mesotheliomas." Cancer 92(10): 2727-32.

²⁸ Ordonez, N. G. (2003). "The immunohistochemical diagnosis of mesothelioma: a comparative study of epithelioid mesothelioma and lung adenocarcinoma." Am J Surg Pathol 27(8): 1031-51.

²⁹ Miettinen, M., J. Limon, et al. (2001). "Calretinin and other mesothelioma markers in synovial sarcoma: analysis of antigenic similarities and differences with malignant mesothelioma." Am J Surg Pathol 25(5): 610-7.

³⁰ Barberis, M. C., M. Faleri, et al. (1997). "Calretinin. A selective marker of normal and neoplastic mesothelial cells in serous effusions." Acta Cytol 41(6): 1757-61.

³¹ Simsir, A., P. Fetsch, et al. (1999). "E-cadherin, N-cadherin, and calretinin in pleural effusions: the good, the bad, the worthless." Diagn Cytopathol 20(3): 125-30.

³² Chhieng, D. C., H. Yee, et al. (2000). "Calretinin staining pattern aids in the differentiation of mesothelioma from adenocarcinoma in serous effusions." Cancer 90(3): 194-200.

³³ Wieczorek, T. J. and J. F. Krane (2000). "Diagnostic utility of calretinin immunohistochemistry in cytologic cell block preparations." Cancer 90(5): 312-9.

³⁴ Davidson, B., S. Nielsen, et al. (2001). "The role of desmin and N-cadherin in effusion cytology: a comparative study using established markers of mesothelial and epithelial cells." Am J Surg Pathol 25(11): 1405-12.

³⁵ Simsir, A., P. Fetsch, et al. (2001). "Calretinin immunostaining in benign and malignant pleural effusions." Diagn Cytopathol 24(2): 149-52.

³⁶ Ordonez NG. Role of immunohistochemistry in distinguishing epithelial peritoneal mesotheliomas from peritoneal and ovarian serous carcinomas. Am J Surg Pathol 1998; 22:1203-14

³⁷ Attanoos RL, Webb R, Dojcinov SD, et al. Malignant epithelioid mesothelioma: anti-mesothelial marker expression correlates with histological pattern. Histopathology 2001; 39:584-8

³⁸ Jorda M, De MB,Nadji M. Calretinin and inhibin are useful in separating adrenocortical neoplasms from pheochromocytomas. Appl Immunohistochem Mol Morphol 2002; 10:67-70

³⁹ King JE, Thatcher N, Pickering CA, et al. Sensitivity and specificity of immunohistochemical markers used in the diagnosis of epithelioid mesothelioma: a detailed systematic analysis using published data. Histopathology 2006; 48:223-32

This page last revised 16.2.2006.

©SMUHT/PW Bishop