Impact of 18F-FDG PET/MR on therapeutic management in high risk primary breast cancer patients - A prospective evaluation of staging algorithms

Eur J Radiol. 2020 Jul:128:108975. doi: 10.1016/j.ejrad.2020.108975. Epub 2020 Apr 24.

Abstract

Purpose: To investigate whether potential differences in staging between a traditional staging imaging algorithm and 18F-FDG PET/MR lead to a change in patient management in breast carcinoma and to compare the diagnostic accuracy between the traditional staging algorithm and 18F-FDG PET/MR for the TNM classification.

Method: In this prospective cohort study from two university hospitals 56 women with newly diagnosed, therapy-naive breast cancer and increased pre-test probability for distant metastases were included. All patients were examined by a traditional staging imaging algorithm (X-ray mammography, breast ultrasonography, chest plain radiography, bone scintigraphy, and ultrasonography of the liver and axillary fossa) and whole-body 18F-FDG PET/MR including dedicated 18F-FDG PET/MR breast examinations. Each patient was discussed two times in a separate tumor board session to determine a total of three therapy recommendations based on histopathological data of the primary tumor and (1) traditional algorithm only, (2) traditional algorithm and 18F-FDG PET/MR, and (3) 18F-FDG PET/MR only. Major changes in therapy recommendations and differences between the traditional staging algorithm and 18F-FDG PET/MR for the TNM classification were evaluated.

Results: Staging by 18F-FDG PET/MR led to a difference in treatment compared the traditional staging algorithm in 8/56 cases (14%). Therapy changes included therapy of the breast, locoregional nodes and systemic therapy. A trend to staging superiority was found for 18F-FDG PET/MRI without statistical significance (p = 0.3827).

Conclusion: In conclusion, for breast cancer patients with elevated pre-test probability for distant metastases a change of the therapy regiment occurs in 14 % of patients when staged by 18F-FDG PET/MR and confirmed by histopathology compared to a traditional staging algorithm. In particular with regard to the amendment of the guideline further assessment of 18F-FDG-PET/MR in this setting is necessary to assess the true value of this modality.

Keywords: Breast cancer; Magnetic Resonance Imaging; TNM staging; positron emission tomography.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Algorithms
  • Breast / diagnostic imaging
  • Breast / pathology
  • Breast Neoplasms / diagnostic imaging*
  • Breast Neoplasms / pathology*
  • Breast Neoplasms / therapy
  • Cohort Studies
  • Female
  • Fluorodeoxyglucose F18*
  • Humans
  • Magnetic Resonance Imaging / methods*
  • Middle Aged
  • Multimodal Imaging / methods
  • Neoplasm Staging
  • Positron-Emission Tomography / methods*
  • Prospective Studies
  • Radiopharmaceuticals*
  • Risk

Substances

  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18