Utility of cell block preparation in diagnosis of paediatric abdominal neoplasms

Paediatric abdominal neoplasms are fairly common. Fine needle aspiration cytology (FNAC) is used for the initial evaluation of paediatric abdominal neoplasms. However, sometimes FNA interpretation can be difficult on limited material, owing to tumour heterogeneity and overlapping features. Therefore, we attempted to obtain additional information using cell block (CB) preparation from residual aspiration material along with immunohistochemistry (IHC) to enhance the diagnostic accuracy.

To evaluate the correlation between CB preparation and FNAC in diagnosis of paediatric abdominal tumours with the help of an extended panel of IHC markers and to highlight some of the diagnostic difficulties.

A total of 113 cases of paediatric abdominal masses were studied. In addition to routine FNA smears, CBs were prepared from the residual material for IHC analysis as considered appropriate.

This study included a total of 113 children with abdominal masses. Histopathology following surgical resection was available in 53 cases. Histology was taken as gold standard to measure the diagnostic accuracy with reference to sensitivity (Sn), specificity (Sp), positive predictive value and negative predictive value. The Sn of FNA alone was 87.5% and Sp was 97.78%. The Sn and Sp increased with use of CB alone and were 100% and 97.78% respectively. The highest Sn and Sp were observed when CB was combined with IHC where both the values were 100%.

CB with IHC is a useful adjunct to the routine FNA smears that further contributes to enhance the accuracy of the cytopathological diagnosis and is useful for choosing pre-operative chemotherapeutic regimen.