Molecular Imaging and Biology

, Volume 19, Issue 4, pp 617–625 | Cite as

Clinical Translation of Tumor Acidosis Measurements with AcidoCEST MRI

  • Kyle M. Jones
  • Edward A. Randtke
  • Eriko S. Yoshimaru
  • Christine M. Howison
  • Pavani Chalasani
  • Robert R. Klein
  • Setsuko K. Chambers
  • Phillip H. Kuo
  • Mark D. Pagel
Research Article



We optimized acido-chemical exchange saturation transfer (acidoCEST) magnetic resonance imaging (MRI), a method that measures extracellular pH (pHe), and translated this method to the radiology clinic to evaluate tumor acidosis.


A CEST-FISP MRI protocol was used to image a flank SKOV3 tumor model. Bloch fitting modified to include the direct estimation of pH was developed to generate parametric maps of tumor pHe in the SKOV3 tumor model, a patient with high-grade invasive ductal carcinoma, and a patient with metastatic ovarian cancer. The acidoCEST MRI results of the patient with metastatic ovarian cancer were compared with DCE MRI and histopathology.


The pHe maps of a flank model showed pHe measurements between 6.4 and 7.4, which matched with the expected tumor pHe range from past acidoCEST MRI studies in flank tumors. In the patient with metastatic ovarian cancer, the average pHe value of three adjacent tumors was 6.58, and the most reliable pHe measurements were obtained from the right posterior tumor, which favorably compared with DCE MRI and histopathological results. The average pHe of the kidney showed an average pHe of 6.73 units. The patient with high-grade invasive ductal carcinoma failed to accumulate sufficient agent to generate pHe measurements.


Optimized acidoCEST MRI generated pHe measurements in a flank tumor model and could be translated to the clinic to assess a patient with metastatic ovarian cancer.

Key Words

CEST MRI pH Bloch fitting Respiration gating Cancer 


Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Supplementary material

11307_2016_1029_MOESM1_ESM.pdf (590 kb)
ESM 1 (PDF 589 kb)


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Copyright information

© World Molecular Imaging Society 2016

Authors and Affiliations

  • Kyle M. Jones
    • 1
  • Edward A. Randtke
    • 2
  • Eriko S. Yoshimaru
    • 3
  • Christine M. Howison
    • 2
  • Pavani Chalasani
    • 4
  • Robert R. Klein
    • 5
  • Setsuko K. Chambers
    • 3
    • 6
  • Phillip H. Kuo
    • 1
    • 2
    • 3
  • Mark D. Pagel
    • 1
    • 2
    • 3
  1. 1.Biomedical Engineering Graduate Interdisciplinary ProgramUniversity of ArizonaTucsonUSA
  2. 2.Department of Medical ImagingUniversity of ArizonaTucsonUSA
  3. 3.University of Arizona Cancer CenterTucsonUSA
  4. 4.Division of Hematology-OncologyUniversity of ArizonaTucsonUSA
  5. 5.Department of PathologyUniversity of ArizonaTucsonUSA
  6. 6.Department of Obstetrics and GynecologyUniversity of ArizonaTucsonUSA

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