CD99 (MIC2, p30/32MIC2, HBA-71)

This is a 30-32 kD cell surface glycoprotein encoded by a pseudoautosomal gene located on the X and Y chromosomes. It is expressed by a range of high grade malignancies.

Antibodies are effective on paraffin-embedded tissue5.

Immunohistochemical expression

Positivity takes the form of strong membrane staining.

Diagnostic utility


1 Ordonez NG. Localized (solitary) fibrous tumor of the pleura. Adv Anat Pathol 2000;7:327-340.

2 Nicholson, S. A., McDermott, M. B., DeYoung, B. R., Swanson, P. E. CD31 immunoreactivity in small round cell tumors. Appl Immunohistochem Molecul Morphol 2000;8:19-24.

3 McCluggage, W. G. Uterine tumours resembling ovarian sex cord tumours: immunohistochemical evidence for true sex cord differentiation Histopathology 1999;34:375-6.

4 Krishnamurthy, S., Jungbluth, A. A., Busam, K. J., Rosai, J. Uterine tumors resembling ovarian sex-cord tumors have an immunophenotype consistent with true sex-cord differentiation. Am J Surg Pathol 1998;22:1078-1082.

5 Leong A S-Y, Cooper K and Leong FJ W-M. Manual of diagnostic antibodies for immunohistology. 2nd edition, 2003

6 Ramani, P., D. Rampling, et al. (1993). "Immunocytochemical study of 12E7 in small round-cell tumours of childhood: an assessment of its sensitivity and specificity." Histopathology 23(6): 557-61.

7 Robertson PB, Neiman RS, Worapongpaiboon S, et al. 013 (CD99) positivity in hematologic proliferations correlates with TdT positivity. Mod Pathol 1997; 10:277-82

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