Abstract

Purpose
Malignant hepatocellular neoplasm, not otherwise specified (HCN-NOS) is a provisional diagnostic entity, characterised by intermediate or a combination of hepatoblastoma and paediatric hepatocellular carcinoma (p-HCC) features. We compared the characteristics of HCN-NOS with hepatoblastoma and p-HCC.
Materials and Methods
The records of 148 paediatric patients diagnosed with hepatocellular malignancy after resection were retrieved from the institutional database. Clinical parameters and histopathology slides were reviewed to re-establish each patient’s diagnosis. Molecular analyses were conducted in 37 patients.
Results
Patients were profiled as 21 (14.2%) with HCN-NOS, 109 (73.6%) with hepatoblastoma, and 18 (12.2%) with p-HCC. The median age was 8.6 years in HCN-NOS, 1.2 years in hepatoblastoma, and 7.9 years in p-HCC. Background liver disease was frequently observed in p-HCC (11/18, 61%) but infrequent in HCN-NOS (4/21, 19%) and hepatoblastoma (4/109, 3.7%). HCN-NOS presented with a more advanced PRETEXT stage (p=0.012), metastasis (p<0.001), and lymphovascular invasion (p<0.001) than hepatoblastoma and p-HCC. Patients with HCN-NOS received longer cycles of preoperative chemotherapy; however, they reported a lower decrease in serum alpha-fetoprotein and tumour size than hepatoblastoma (p=0.043, 0.004, 0.044, respectively). HCN-NOS was an independent poor prognostic factor for event-free survival (hazard ratio, 4.968; 95% confidence interval, 2.004–12.32; p<0.001).
Conclusion
The possibility of HCN-NOS should be considered in paediatric patients with liver cancer, especially those ≥ 5 years old with no background liver disease. Because HCN-NOS exhibits poor chemo-responsiveness and unfavourable postoperative prognosis, liver transplantation should be strongly considered.

• Keywords: Liver neoplasms, Hepatoblastoma, Carcinoma, Hepatocellular, Histology, Diagnosis, Prognosis