Correlation between NEN Bone Metastasis Performance and Tumor Proliferation: 112 Cases of [68Ga]Ga-DOTA-TATE Result Analysis.

PURPOSE: This study aimed to analyze neuroendocrine neoplasm (NEN) bone metastasis (BM) and gallium-68 (68Ga)-DOTA-TATE performance and to explore their correlation with the immunohistochemical proliferation index (Ki-67).

PROCEDURES: A total of 112 patients with BMs were screened from 1082 NEN patients who underwent [68Ga]Ga-DOTA-TATE imaging. All patients had pathological results, and BMs were affirmed by clinical/imaging follow-up and/or histopathology. The maximum standard uptake value (SUVmax) ratio of BM to normal bone determined for each patient was used in the final analysis.

RESULTS

The incidence rate of BMs in NENs was 10.35%. BMs occurred in the spine (75%), pelvis (72.3%), ribs (58%), clavicles and scapulae (41.1%), limbs (37.5%), and skull (28.6%). Most cases were associated with liver metastases (70.5%) and lymph node metastases (65.2%) simultaneously. The SUVmax ratio of G3b (median ratio = 3.77, Ki-67 >55%) was significantly lower than that of G1 (11.43, Ki-67 ≤2%) and G2a (11.15, 3% ≤ Ki-67 ≤10%) separately (p < 0.05), while no differences were found for G2b (8.5, 11% ≤ Ki-67 ≤55%) and G3a (6.64, Ki-67 >55%) groups. In the total patients, there was a significant negative correlation between the SUVmax ratio of BMs to normal bone and Ki-67 (r = -0.267, p < 0.01). According to the changes in bone density on CT scans, the cases were divided into 4 groups: osteogenesis, osteolysis, no change, and a mixed group (median Ki-67: 6.5%, 15%, 12%, and 22.5%). The Ki-67 values were significantly different between the osteogenesis group and the other groups (p < 0.05).

CONCLUSION

BM is present in 10.35% of NEN patients and most have simultaneous liver and/or lymph node metastases. The occurrence of osteogenesis indicates relatively good differentiation, and there is a negative correlation between SUVmax ratio of BMs and NEN proliferation.