Development of malignancy evaluation method for chondrogenic tumor using MRI molecular imaging

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K16462
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Radiation science
• Research Institution: Kagoshima University
• Principal Investigator: Nakajo Masanori 鹿児島大学, 鹿児島大学病院, 特任助教 (60727171)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: GagCEST / グルコサミノグリカン / 軟骨形成腫瘍

Outline of Final Research Achievements

GAG CEST was imaged in about 50 bone tumors during the study period, and the CEST effect of GAG in the tumor was quantitatively evaluated. Of the evaluated cases, 4 were diagnosed as cartilage tumors. Image analysis was performed with consideration of the results of phantom data, but GAG CEST was quantified only in 2 out of 4 cases, but high-grade chondrosarcoma G3 had lower GAG CEST values than enchondroma, which was benign. However, the number of cases was small and statistical analysis could not be performed. In this study, the usefulness of benign and malignant differentiation of cartilage tumors in GAG CEST could not be proved, but it is also considered that it was difficult to collect target cases and calculate optimal GAG CEST value.

Free Research Field

放射線診断学

Academic Significance and Societal Importance of the Research Achievements

良性である内軟骨腫・低悪性度軟骨肉腫と高悪性度軟骨肉腫では治療・予後が異なるため、画像でより正確に両者を鑑別する事は最適な治療法を選択する上で非常に有意義であるが、従来の画像診断では鑑別が困難な事が少なくない。高悪性度軟骨肉腫では内軟骨腫・低悪性度軟骨肉腫と比べ腫瘍内のGAG量は低いと考えられ、軟骨基質に特異的な物質であるGAGは軟骨形成腫瘍の良悪性鑑別のマーカーになり得るがGAGの画像化に基づく良悪性鑑別の画像法は報告されていない。GagCESTのような新たな分子イメージング法の研究ならびに臨床応用の確立は正確な質的診断・悪性度診断を可能とし最適な治療方針の決定・予後評価を可能する。