CD44s expression correlated with the International Neuroblastoma Pathology Classification (Shimada system) for...

CD44 is a cell adhesion molecule that plays an important role in the cascade of metastasis and progression of human malignant tumours. A large family of variants or isoforms, generated by alternative splicing of a single gene, has been reported to be involved in the malignant process by conferring metastatic potential to non-metastatic cells. The objective of this study was to compare the expression of CD44 standard molecule with the International Neuroblastoma Pathology Classification (INPC) for neuroblastic tumours, a histological grading system based on the Shimada system for predicting the clinical outcome in neuroblastic tumours.

Paraffin blocks of primary neuroblastic tumour were graded according to the INPC system into favourable and unfavourable histological types. Tumour tissues were then analysed with immunostaining using monoclonal antibodies against the CD44 epitope.

In this retrospective study, 32 cases of primary neuroblastic tumour were collected. Based on the INPC system, 13 cases (40.6%) had a favourable histology while 19 cases (59.4%) were of unfavourable histology. CD44 standard (CD44s) expression was detected in 69.2% of neuroblastic tumours with favourable histological type while 89.5% of tumours with unfavourable histological type did not express CD44s staining. Statistically, there was significant correlation between morphological grading of neuroblastic tumours based on the INPC and the presence of CD44 staining (Fisher's exact test, P<0.05).

This study shows that there is a significant correlation between CD44s expression and tumour histology based on the INPC in which CD44s non-expression is correlated with an unfavourable histological type and the expression of CD44s with a favourable type. Therefore, the analysis of CD44s expression should be recommended as an additional biological marker in the initial routine staging of the disease.