18F-FDG PET/CT imaging characteristics of Castleman's disease

Objective To evaluate the imaging characteristics of 18F-FDG PET/CT in patients with Castleman's disease (CD). Methods Twelve patients (male 7, female 5, mean age: (51.2±19.3) years) with pathologically confirmed CD and 18F-FDG PET/CT were retrospectively enrolled. A lesion with SUVmax greater than that of normal liver tissue was defined as positive. Lesion size (short diameter) was measured. Correlation between size and SUVmax was analyzed by Pearson correlation analysis. SUVmax of different clinical and pathological types was compared using Mann-Whitney rank sum test. Results Among 12 patients, 7 patients had localized CD (LCD) involving a single group of lymph nodes and 5 patients had multicentric CD (MCD) involving more than one group of lymph nodes with some having lung and spleen infiltration. A total of 129 positive lesions were found (7 of LCD, 122 of MCD) and the average SUVmax was 4.20±1.84 (range: 2.50 to 10.70). There was no significant correlation between SUVmax and lesion size (r=0.189, P>0.05). There was no significant difference in SUVmax between LCD and MCD (4.23±1.77 vs 4.19±1.86; Z=-0.108, P>0.05); but there was significant difference in SUVmax between the patients with and without clinical manifestations (4.56±2.06 vs 3.41±0.87; Z=-2.443, P 0.05). Conclusions CD shows primarily lymph node involvement with increased 18F-FDG uptake. However, the degree of FDG uptake does not correlate with clinical presentation or pathological types. Key words: Giant lymph node hyperplasia; Tomography, emission-computed; Tomography, X-ray computed; Deoxyglucose