Cytokeratin 14

This is an acidic cytokeratin. It is expressed by myoepithelium and by the basal cells of keratinised squamous epithelium.

Immunohistochemical expression

Normal tissues:

• myoepithelial cells of breast glands and ducts

• myoepithelial cells of salivary gland ducts and acini

• basal layer of epidermis and squamous mucosa

Carcinomas:

The frequency of immunoreactivity of squamous cell carcinomas appears to be independent of the degree of differentiation. Considering the squamous cell carcinomas listed above:

There is evidence that oncocytic tumours are immunoreactive, including Hurtle cell adenomas of the thyroid, Warthin tumours of the salivary glands and oxyphil adenomas of the parathyroid4. Another study has confirmed the positivity of oncocytic tumours from a variety of anatomic sites and shown its value in the differentiation of renal oncocytoma from its mimics.

Diagnostic utility

• Identification of squamous cell carcinomas, particularly those which are poorly differentiated. It may be used in combination with p63 and CK5/68.

• Differentiation of oxyphil adenomas from carcinomas of the parathyroid4.

• Differentiation of intraduct from invasive salivary duct carcinoma by the positive staining of basal cells surrounding the in-situ neoplasm5.

• Differentiation of benign from malignant prostatic glands. Staining is often very intermittent, and is absent from some benign glands, while background staining is stronger than for either LP34 or CK5/6. The latter are probably therefore superior for this usage7.

• Differentiation of oncocytomas from their mimics9.

References

1 Chu, P. G., Lyda, M. H., Weiss, L. M. Cytokeratin 14 expression in epithelial neoplasms: a survey of 435 cases with emphasis on its value in differentiating squamous cell carcinomas from other epithelial tumours. Histopathology 2001;39:9-16.

2 Lyda, M. H., Weiss, L. M.. Immunoreactivity for epithelial and neuroendocrine antibodies are useful in the differential diagnosis of lung carcinomas. Human Pathol 2000;31:890-897.

3 Harnden, P., Southgate, J. Cytokeratin 14 as a marker of squamous differentiation in transitional cell carcinomas. J Clin Pathol 1997;50:1032-3.

4 Erickson, L. A., Jin, L., Papotti, M., Lloyd, R. V. Oxyphil parathyroid carcinomas: a clinicopathologic and immunohistochemical study of 10 cases. Am J Surg Pathol 2002;26:344-349.

5 de Araujo, V.C., Kowalski, L.P., Soares, F., de Araujo, N.S., Loducca, S.V. and Sobral, A.P. Salivary duct carcinoma: cytokeratin 14 as a marker of in-situ intraductal growth. Histopathology 2002;41:244-9.

6 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.

7 Freeman, A., K. Treurnicht, et al. (2002). "A comparison of basal cell markers used in the prostate." Histopathology 40(5): 492-4.

8 Reis-Filho JS, Simpson PT, Martins A, Preto A, Gartner F,Schmitt FC Distribution of p63, cytokeratins 5/6 and cytokeratin 14 in 51 normal and 400 neoplastic human tissue samples using TARP-4 multi-tumor tissue microarray. Virchows Arch 2003; 443:122-32 This study used tissue microarrays.

9 Chu PG,Weiss LM Cytokeratin 14 immunoreactivity distinguishes oncocytic tumour from its renal mimics: an immunohistochemical study of 63 cases. Histopathology 2001; 39:455-62

This page last revised 21.1.2007.

©SMUHT/PW Bishop