Hybrıd F18-FDG PET/MRI in endometrial cancer: staging accuracy, quantitative analysis, and imaging characteristics of histological subtypes
Diğdem Kuru Öz, Ankara / Turkey
Author Block: D. Kuru Öz, M. Araz, S. N. Yılmazer Zorlu, B. Varlı, C. Soydal, S. Taşkın, E. Ozkan, G. A. Erden, O. Kücük; Ankara/TRPurpose: The aim of this study is to evaluate the diagnostic performance of F18-FDG PET/MRI in endometrial cancer (EC) staging, determine the individual contributions of PET and MRI, compare PET/CT and PET/MRI findings, quantitatively assess the primary tumor (PT) and metastatic lymph nodes (LN), and investigate the differences in quantitative measurements among histological subtypes.Methods or Background: Between February 2020 and March 2022, a total of 44 patients who were diagnosed with EC via biopsy were included in the study. Following whole-body PET/CT, pelvic PET/MRI was performed. For quantitative analysis, the apparent diffusion coefficient (ADC) values for PT and LN were measured with MRI, while the maximum standard uptake value(SUVmax), metabolic tumor volume(MTV), and total lesion glycolysis(TLG) values were measured with PET/CT and PET/MRI. For statistical analysis Spearman correlation and Mann-Whitney U tests were performed.Results or Findings: Out of the 44 patients, 39 (- 6%) had concordance between PET/MRI staging and pathological staging, while 5 (11.3%) were discordant.
There were nine patients (- 4%) with pelvic and/or para-aortic LN metastasis. In three patients (6.8%) with suspected LN involvement on MRI, PET accurately predicted LN involvement with pathological activity.
In LN evaluation, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for PET/CT were - 6%, 93.9%, 66.6%, 91.1%, and 88%, respectively. For PET/MRI, the corresponding values were 88.8%, 88.2%, 66.6%, 96.7%, and 88.3%, respectively.
For both PT and pathological LN, no strong correlation was found between ADC and SUVmax values (r> -- 009, p> 0.095,respectively).
Conclusion: PET/MRI, can be used in preoperative staging for the accurate assessment of both the primary tumor and nodal involvement. It offers high negative predictive value and has the potential to prevent unnecessary lymph node dissections while providing a high diagnostic performance as a hybrid imaging method.Limitations: The limitation of this study is the small sample size.Funding for this study: No funding was received for this study.Has your study been approved by an ethics committee? YesEthics committee - additional information: The Institutional Ethics Committee approved this retrospective study protocol and waived informed consent