Does Chemotherapy Have an Effect on the Treatment Success of Children and Adolescents with Unresectable Hepatocellular Carcinoma? Findings from the German Liver Tumour Registry.

: Paediatric hepatocellular carcinoma (HCC), including its fibrolamellar variant (FLC), is a rare malignancy with distinct biological behaviour and limited therapeutic options. While complete surgical resection is a key determinant of survival, many patients present with unresectable tumours at diagnosis. The role of neoadjuvant chemotherapy in improving resectability, particularly in histologically distinct subtypes, remains inconclusive. : We retrospectively analysed 43 patients (<18 years) with histologically confirmed conventional HCC (cHCC, = 27) or FLC ( = 16) enrolled in the German Pediatric Liver Tumour Registry. We assessed clinical characteristics, treatment response, surgical outcomes, and survival. Special focus was placed on the impact of neoadjuvant chemotherapy in initially unresectable tumours. : FLC and cHCC exhibited significant differences in clinical presentation, such as age of presentation, AFP elevation, or presence of underlying liver disease. Although overall survival did not significantly differ between groups, cHCC tumours showed a markedly higher response to chemotherapy (62.5% partial remission vs. 0% in FLC). Complete resection (R0) was achieved in 77% of all patients and was the strongest predictor of survival. Importantly, a subset of cHCC patients who initially had unresectable tumours became eligible for curative surgery following neoadjuvant chemotherapy. Notably, delayed resection after chemotherapy led to outcomes comparable to those with upfront surgery, whereas progression during chemotherapy was associated with a universally poor prognosis. : This study supports upfront resection as the preferred strategy in paediatric HCC and FLC whenever feasible. In cHCC, neoadjuvant chemotherapy demonstrated a favourable response profile and contributed to secondary resectability in a subset of initially unresectable cases, supporting a potential role within a multimodal treatment approach. In contrast, FLC showed limited responsiveness to current systemic therapies. These findings emphasise the importance of histology-specific strategies and highlight the ongoing need for more effective systemic options, particularly for unresectable FLC.