Abstract:

Objective To investigate the value of ¹⁸F-fluorodeoxyglucose （¹⁸F-FDG） PET/CT in the differential diagnosis of primary intestinal diffuse large B-cell lymphoma （PIDLBCL） and colon cancer in the ileocecal region. Methods A total of 42 patients with ileocecal tumors admitted to Nanjing Drum Tower Hospital， Affiliated Hospital of Nanjing University Medical School from June 2013 to December 2023 were selected as the study objects， including 17 cases of PIDLBCL and 25 cases of colon cancer. General data and ¹⁸F-FDG PET/CT parameters were compared between patients with PIDLBCL and colon cancer in the ileocecal region. Binary logistic regression was used to analyze the independent influencing factors for the differential diagnosis of PIDLBCL and colon cancer in the ileocecal region. The receiver operator characteristic （ROC） curve was used to evaluate the diagnostic efficacy of independent influencing factors. Results There were statistically significant differences in tumor length diameter （Z=-2.63， P=0.009）， maximum thickness （Z=-3.26， P=0.001）， ileal involvement （χ²=6.04， P=0.014）， intestinal dilation （χ²=10.38， P=0.001）， maximum standardized uptake value （SUV_max） （Z=-3.73， P<0.001）， SUV_mean （Z=-3.40， P<0.001）， metabolic tumor volume （Z=-2.37， P=0.018） and total lesion glycolysis （Z=-2.93， P=0.003） between patients with PIDLBCL and colon cancer in the ileocecal region. Multivariate analysis showed that SUV_max （OR=1.16， 95%CI： 1.04-1.31， P=0.011） and intestinal dilation （OR=6.64， 95%CI： 1.13-39.10， P=0.036） were both independent influencing factors for the differential diagnosis of PIDLBCL and colon cancer in the ileocecal region. ROC curve analysis showed that， the areas under the curve of SUV_max and intestinal dilation for the differential diagnosis of PIDLBCL and colon cancer in the ileocecal region were 0.84 （95%CI： 0.70-0.94） and 0.73 （95%CI： 0.58-0.86）， respectively. The optimal cut-off value for SUV_max was determined to be 19.14， with a sensitivity of 70.6% and a specificity of 88.0%， while intestinal dilation exhibited a sensitivity of 58.8% and a specificity of 88.0%. Conclusions ¹⁸F-FDG PET/CT can be used for the differential diagnosis of PIDLBCL and colon cancer in the ileocecal region， and SUV_max and intestinal dilation have high diagnostic efficacy.

Key words: Colonic neoplasms, Lymphoma， large B-cell， diffuse, Positron emission tomography computed tomography, Fluorodeoxyglucose F18, Ileocecal region