Objective·To analyze the imaging characteristics and diagnostic value of 18F-fluorodeoxyglucose positron emission tomography-computed tomography(18F-FDG PET/CT)in mantle cell lymphoma(MCL)and explore its application to distinguishing between classic and aggressive variants of MCL.Methods·A retrospective analysis was conducted on the 18F-FDG PET/CT images and clinical data of 116 pathologically confirmed,newly diagnosed MCL patients.The imaging features of intra-and extra-nodal lesions were summarized.The accuracy of 18F-FDG PET/CT in diagnosing bone marrow and gastrointestinal involvement in MCL was evaluated.Furthermore,differences in 18F-FDG PET/CT findings and clinical characteristics between the classic and aggressive variants of MCL were analyzed.Results·Among the 116 patients,100.0%showed positive findings on 18F-FDG PET/CT,with 99.1%exhibiting abnormal lymph nodes and 85.3%having extra-nodal involvement.The most common extra-nodal sites were the spleen,Waldeyer's ring,bone marrow,and gastrointestinal tract.Compared with bone marrow aspiration results,the sensitivity,specificity,and accuracy of 18F-FDG PET/CT for detecting bone marrow involvement in MCL were 43.4%,91.5%,and 66.0%,respectively.When compared with endoscopic biopsy results,the sensitivity of 18F-FDG PET/CT for detecting gastric and intestinal involvement was 100.0%and 94.1%,respectively,with specificity of 75.0%and 100.0%,and accuracy of 92.9%and 94.7%,respectively.There were significant differences in the highest maximum standardized uptake value(SUVmax)and Ki-67 index between the classic and aggressive variants of MCL,with SUVmax positively correlated with Ki-67 index.By using SUVmax>10.4 as the diagnostic threshold,the sensitivity and specificity for differentiating between the classic and aggressive variants of MCL were 73.9%and 77.4%,respectively,with an AUC value of 0.797.Conclusion·18F-FDG PET/CT demonstrates a high detection rate for both intra-and extra-nodal lesions in MCL patients.It exhibits high specificity in diagnosing bone marrow involvement and high sensitivity and specificity in diagnosing gastrointestinal involvement,providing reliable non-invasive diagnostic information for MCL bone marrow and gastrointestinal involvement.However,it is not a substitute for pathological examination.Additionally,the positive correlation between SUVmax and Ki-67 index allows SUVmax to effectively differentiate between the classic and aggressive variants of MCL,with a higher SUVmax(>10.4)indicating a higher likelihood of the aggressive variant.These findings have clinical implications for treatment planning and prognosis assessment.

Objective·To analyze the imaging characteristics and diagnostic value of 18F-fluorodeoxyglucose positron emission tomography-computed tomography(18F-FDG PET/CT)in mantle cell lymphoma(MCL)and explore its application to distinguishing between classic and aggressive variants of MCL.Methods·A retrospective analysis was conducted on the 18F-FDG PET/CT images and clinical data of 116 pathologically confirmed,newly diagnosed MCL patients.The imaging features of intra-and extra-nodal lesions were summarized.The accuracy of 18F-FDG PET/CT in diagnosing bone marrow and gastrointestinal involvement in MCL was evaluated.Furthermore,differences in 18F-FDG PET/CT findings and clinical characteristics between the classic and aggressive variants of MCL were analyzed.Results·Among the 116 patients,100.0%showed positive findings on 18F-FDG PET/CT,with 99.1%exhibiting abnormal lymph nodes and 85.3%having extra-nodal involvement.The most common extra-nodal sites were the spleen,Waldeyer's ring,bone marrow,and gastrointestinal tract.Compared with bone marrow aspiration results,the sensitivity,specificity,and accuracy of 18F-FDG PET/CT for detecting bone marrow involvement in MCL were 43.4%,91.5%,and 66.0%,respectively.When compared with endoscopic biopsy results,the sensitivity of 18F-FDG PET/CT for detecting gastric and intestinal involvement was 100.0%and 94.1%,respectively,with specificity of 75.0%and 100.0%,and accuracy of 92.9%and 94.7%,respectively.There were significant differences in the highest maximum standardized uptake value(SUVmax)and Ki-67 index between the classic and aggressive variants of MCL,with SUVmax positively correlated with Ki-67 index.By using SUVmax>10.4 as the diagnostic threshold,the sensitivity and specificity for differentiating between the classic and aggressive variants of MCL were 73.9%and 77.4%,respectively,with an AUC value of 0.797.Conclusion·18F-FDG PET/CT demonstrates a high detection rate for both intra-and extra-nodal lesions in MCL patients.It exhibits high specificity in diagnosing bone marrow involvement and high sensitivity and specificity in diagnosing gastrointestinal involvement,providing reliable non-invasive diagnostic information for MCL bone marrow and gastrointestinal involvement.However,it is not a substitute for pathological examination.Additionally,the positive correlation between SUVmax and Ki-67 index allows SUVmax to effectively differentiate between the classic and aggressive variants of MCL,with a higher SUVmax(>10.4)indicating a higher likelihood of the aggressive variant.These findings have clinical implications for treatment planning and prognosis assessment.