Characteristics of neuroendocrine neoplasm metastasis in somatostatin receptor PET/CT imaging: a retrospective analysis / 中华核医学与分子影像杂志

ABSTRACT

Objective To investigate the characteristics of NEN metastasis with SSTR PET/CT and to correlate the results with FDG-PET and pathology.Methods From November 2011 to August 2016,a total of 43 patients with NEN (18 males,25 females;age range26-74 years) were recruited into this retrospective study;they underwent 68Ga-DOTA-TATE PET/CT (TATE-PET) imaging 40-60 min after 44.4-229.4 MBq 68Ga-DOTA-TATE administration.Metastases in 31 patients were confirmed by histopathology and in 12 patients by follow-up and other imaging modalities.Twenty-eight of 43 patients finished routine FDG-PET in a week after TATE-PET.PET/CT results were considered positive when the metastatic lesions were tracer-avid.ROI was drawn over each lesion for size and SUV measurement.x2 test and Pearson correlation analysis were used for statistical analysis.Results (1) Of 43 patients,TATE-PET detection rates of metastasis in the liver,lymph nodes,bones.and lungs were 85.7％(30/35),12/13,7/7,2/3,respectively,with their corresponding SUVmax of 18.1(11.3-23.3),10.8(5.4-15.6),7.7(4.2-9.9) and 1.8(1.3-2.3),respectively.Statistical correlation between size and SUVmax was found in metastatic bone lesions(r=0.233,P＜0.05).(2) In 31 patients with histopathologically proven metastasis,TATE-PET detected 23/24 (95.8％) G2,1/2 G1 and 5/5 G3 metastases.G1 metastases were only found in the liver.(3)Among 28 patients underwent both TATE-PET and FDG-PET,there was no significant difference between the detecting rate of metastasis89.2％ (25/28) vs 71.4％ (20/28);x2 =2.389,P＞0.05.Compared with FDG-PET,TATE-PET was superior in demonstrating metastasis in the liver and bones (70.0％ (14/20) vs 65.0％ (13/20),3/3 vs 2/3),equal in detecting lung metastasis (both 2/3) but inferior in demonstrating metastasis in lymph nodes (9/10vs 10/10).Conclusions The capability of TATE-PET in revealing NEN metastasis varies depending on lesion localization and histologic grade.TATE-PET and FDG-PET are complementary to each other in detection of NEN metastasis,but without obvious relationship to histologic grade.