The diagnostic and prognostic value of SALL 4 in hepatoblastoma

Aims To investigate the expression of spalt‐like transcription factor 4 ( SALL 4), a regulator of embryonal development, in three epithelial components of hepatoblastoma ( HB ) and the relationship between SALL 4 expression levels and patients’ clinicopathological features. Methods and results A total of 115 specimens from 79 patients with HB were selected for immunostaining of SALL 4. Nuclear staining was semi‐quantified using the immunoreactive score ( IS ; range: 0–12). SALL 4 expression was seen in all embryonal components (mean IS = 8.58) and in 41% of fetal components (mean IS = 0.78). No SALL 4 expression was seen in either small cell undifferentiated or mesenchymal components of HB . Neither chemotherapy nor metastasis altered SALL 4 expression significantly. High SALL 4 expression levels were associated significantly with decreased overall survival ( OS ) ( P = 0.004), event‐free survival ( EFS ) ( P = 0.003) and the presence of metastasis ( P = 0.049) on univariate analysis. Multivariate analysis identified SALL 4 as an independent prognostic predictor for OS ( P = 0.029). Conclusions SALL 4 is useful for subtyping HB , and high SALL 4 expression is associated with decreased survival in HB .