72317 - Improved survival but early recurrence, resection of intrahepatic cholangiocarcinoma with high tumour burden – a rationale for neoadjuvant therapy?

Abstract Introduction Neoadjuvant therapy has not been established as standard of care in intrahepatic cholangiocarcinoma (iCCA). The role of resection surgery in patients with large or multifocal iCCA remains debated. The aim of this study was to examine oncological outcomes in a regional all-comer cohort. Method All patients diagnosed with iCCA at the Stockholm regional tumour board (Karolinska University Hospital, 2010-2020) were assessed. Patients without distant lymph node metastasis or metastasis to other organs were included. The primary outcome was overall survival (OS), calculated from date of diagnosis. The secondary outcome was disease-free survival (DFS), calculated from date of surgery. Result One-hundred and twenty-eight patients were diagnosed with liver-only iCCA. Approximately half of patients (n=62, 48%) underwent curative intent surgery, while the other half underwent either palliative chemotherapy (n=33, 26%) or best supportive care (n=33, 26%). A majority of patients (n=75, 59%) had an iCCA larger than 5 cm or more than 5 tumours (high tumour burden group). For patients with high tumour burden, OS was significantly better after resection (Figure 1A, P0.001). After resection, median DFS was shorter in patients with high tumour burden (Figure 1B, 5.5 months vs. 23.5 months, P=0.002). Discussion In this regional all-comer cohort, surgical resection of iCCA was associated with improved OS even in patients with high tumour burden. However, median DFS was less than six months in the high tumour burden group. The better survival but high risk of early recurrence indicates that large or multifocal iCCA should be further investigated as possible indications for neoadjuvant therapy.