Identification of risk and prognostic factors for patients with clonorchiasis-associated intrahepatic cholangiocarcinoma.

Background: Intrahepatic cholangiocarcinoma caused by clonorchiasis (CICC) has a poor prognosis, and there have been insufficient studies regarding risk and prognostic factors. We aimed to identify CICC-associated factors.

Methods: A retrospective analysis of 127 eligible patients with CICC was performed with 254 clonorchiasis cases used as matched controls to identify risk factors for CICC. The main outcomes analyzed included overall survival (OS) and disease-free survival (DFS).

Results: Out of 127 surgeries, R0 resection was performed in 61 patients, R1 in 32 patients, and R2 in 22 patients; nonresection surgery was performed in 12 patients. Median OS for the entire cohort was 29.5 months. Median OS and DFS for 61 patients with R0 resection were 52.4 months and 41.5 months, respectively. We found independent risk factors for CICC were duration of raw fish consumption of ≥28 years (p < 0.001) and hepatitis B virus infection (p = 0.040). R0 resection (p < 0.001), well or moderately differentiated tumor (p = 0.019), and stage I to II tumor (p < 0.001) predicted improved OS for CICC. Serum carcinoembryonic antigen level of ≤5 ng/ml (p = 0.029) and stage I to II tumor (p < 0.001) predicted improved DFS.

Conclusions: Duration of raw fish consumption ≥28 years and hepatitis B virus infection were significant risk factors for CICC in patients with clonorchiasis. For patients with CICC, curative resection is an effective treatment. Higher tumor differentiation and earlier American Joint Committee on Cancer stage predicted good prognosis. Serum carcinoembryonic antigen level was found to predict the possibility of recurrence after curative resection.