Background: The aim of this study was to assess the diagnostic performance of radiological imaging in differentiating xanthogranulomatous cholecystitis (XGC) from gallbladder cancer (GBC). Methods: A retrospective analysis of the radiological imaging performed in patients who had pathologically confirmed XGC or GBC between December 2004 to April 2016 was performed. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of each imaging modality, and combined imaging modalities were calculated. Results: A total of 218 patients (XGC =109, GBC =109) were identified; 19 patients received all of abdominal ultrasound (US), contrast-enhanced ultrasound (CEUS), computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET/CT); 21 received four of these imaging examination types; 45 received three examinations; 58 received two examinations; and 75 received only one examination. The sensitivity and specificity of CEUS was 90% and 93%, respectively, higher than abdominal US (80%, 86%), CT (71%, 92%), MRI (75%, 90%), and PET/CT (55%, 90%) (all values respective). The sensitivity, specificity, NPV, and PPV of the US combined with CEUS were 91%, 90%, 94%, and 85%, respectively. Although the specificity of CEUS + CT and CEUS + MRI were 100% and 92%, respectively, the sensitivity of CEUS + CT and CEUS + MRI were both only 67%. Conclusions: The Abdominal US is not sufficiently accurate to confidently guide clinical practice, and CEUS showed better diagnostic performance than the other imaging modalities in differentiating XGC from GBC. The combination of abdominal CEUS and CT is helpful for differential diagnosis, as it indicates GBC with better specificity and PPV.

Tumor‐infiltrating neutrophils (TIN) carry out quite significant but opposite functions in different cancers, and their function in biliary cancer has not been fully characterized. To investigate the prognostic significance of TIN in biliary cancer, a training set (n = 118) and a validation set (n = 127) were involved in this study. TIN were evaluated by immunohistochemical staining of CD66b, and then defined as low (neutrophils <18/high‐power field [HPF]) vs high (neutrophils ≥18/HPF). Kaplan‐Meier curve, Cox proportional hazards models and receiver operating characteristic curve were used to assess the prognostic significance. TIN was identified as an independent prognostic factor for overall survival in the training set (HR: 4.720; 95% CI: 2.623‐8.493; P < .001) which was confirmed in the validation set (HR: 4.993; 95% CI: 2.626‐9.492; P < .001). Notably, among patients with stage III and IV disease, those with low TIN could benefit from adjuvant chemotherapy, with a reduced risk of compromised survival compared with those with high TIN (HR: 0.294; 95% CI: 0.099‐0.873; P = .047 in the training set; and HR: 0.100; 95% CI: 0.022‐0.462; P = .006 in the validation set). In addition, TIN were negatively related to biological pathways as regulation of activated T‐cell proliferation and lymphocyte‐mediated immunity, and showed a negative correlation with CD8 + T cells (r = −.324, P < .001). Taken together, our results implicate TIN as an independent marker of prognosis and indicator of patients who would benefit from adjuvant chemotherapy in biliary cancer.