Research

Expression of CD56 isoforms in primary and relapsed adult granulosa cell tumors of the ovary

Hans-Ullrich Völker¹ , Sabine Engert² , Andreas Cramer³ , Melanie Schmidt² , Ulrike Kämmerer² , Hans-Konrad Müller-Hermelink¹ and Stefan Gattenlöhner¹

¹University of Würzburg, Institute of Pathology, Würzburg, Germany

²University of Würzburg, Dept. of Gynaecology, Würzburg, Germany

³Missionsärztliche Klinik, Dept. of Gynaecology, Würzburg, Germany

author email corresponding author email

Diagnostic Pathology 2008, 3:29doi:10.1186/1746-1596-3-29

Published:	9 July 2008

Abstract

Background

Adult granulosa cell tumors of the ovary (GCTs) are sex cord stromal tumors of unpredictable behaviour. Up to now, the prediction of the relapsing/malignant potential remains difficult. CD56 (NCAM) in GCTs was previously described in only two studies. However, the expression of its isoforms was not examined.

Methods

30 GCTs (16 primaries, 14 relapses) were investigated immunohistochemically with antibodies against Pan-CD56 (CD56^Pan) and the isoform with 140/180 kDa length (CD56^{140/180 kDa}). The reaction was assessed with respect to percentage of positive cells and intensity of staining.

Results

In all GCTs, CD56^Pan was expressed, but differences were found between primaries and relapses. The percentage of CD56^Pan positive tumor cells was lower in relapses, whereas CD56^{140/180 kDa} showed a higher staining intensity in the latter.

Conclusion

Expression of CD56 is an additional sensitive and helpful immunohistochemical tool for histopathologists diagnosing a GCT. It does not seem possible to provide a validly individual risk assessement. However, the different expression of CD56 isoforms might indicate important changes in the course to a more malignant behaviour.