Octamer-binding transcription factor 4-positive circulating tumor cell predicts worse treatment response and survival in advanced cholangiocarcinoma patients who receive immune checkpoint inhibitors treatment

Octamer-binding transcription factor 4-positive circulating tumor cell (OCT4+CTC) exhibits high stemness and invasive potential, which may influence the efficacy of immune checkpoint inhibitors (ICI). This study aimed to assess the prognostic role of OCT4+CTC in advanced cholangiocarcinoma (CCA) patients who received ICI treatment. In total, 40 advanced CCA patients who received ICI treatment were included, and CTC and OCT4 counts were detected via a Canpatrol system and an RNA in situ hybridization method before ICI treatment. Patients were subsequently divided into none CTC, OCT4−CTC, and OCT4+CTC groups. Patients were followed up for a median of 10.4 months. The percentages of patients in none CTC, OCT4−CTC, and OCT4+CTC groups were 25.0