A prospective study of tumor-stroma ratio in resected intrahepatic mass-forming cholangiocarcinoma: prognostic value and correlation with gadoxetic acid-enhanced MRI.

Abstract

To assess the prognostic value of tumor-stroma ratio (TSR) in intrahepatic mass-forming cholangiocarcinoma (IMCC) and its subtypes, and to explore the correlation between gadoxetic acid-enhanced MRI and TSR. This prospective study included participants with suspected IMCC who underwent gadoxetic acid-enhanced MRI and curative resection between March 2022 and December 2024. Participants were divided into stroma-poor and stroma-rich groups. Clinicopathologic and MRI features were assessed. Cox regression analysis and Kaplan-Meier curves were used to compare recurrence-free survival (RFS) rate. Logistic regression analysis was used to identify factors associated with TSR. A total of 86 participants (mean age 65 ± 9 years) were included, with 60 small-duct (SD) and 26 large-duct (LD) IMCC; 54 were classified as stroma-rich and 32 as stroma-poor. Participants with stroma-poor IMCC had a higher risk of recurrence than those with stroma-rich IMCC in the whole cohort (p = 0.002) and in the SD subtype (p < 0.001). TSR was an independent predictor for RFS in the whole cohort (hazard ratio = 2.755; 95% CI: 1.324, 5.735; p = 0.007) and in SD subtype (hazard ratio = 4.053; 95% CI: 1.575, 10.431; p = 0.004). The contrast-enhancement ratio on hepatobiliary phase (CER_HBP) image was associated with TSR in the whole cohort (odds ratio = 0.016; 95% CI: 0.001, 0.259; p = 0.004) and in SD subtype (odds ratio = 0.020; 95% CI: 0.001, 0.544; p = 0.020). Poor tumor-stroma is associated with an unfavorable prognosis in IMCC, especially in the SD subtype. The CER_HBP is a promising tool for the noninvasive assessment of TSR. Question The prognostic implication of the TSR in IMCC and its subtypes, and its correlation with gadoxetic acid-enhanced MRI characteristics, remain inadequately understood. Findings Poor tumor-stroma is identified as a significant risk factor for recurrence, and the CER_HBP is associated with TSR in SD IMCC. Clinical relevance This study introduces a noninvasive approach to evaluate TSR in IMCC, especially in the SD subtype, and underscores the significance of TSR as a prognostic indicator, potentially aiding in the development of new personalized therapeutic strategies.