Predictive Value of Diffusion, Glucose Metabolism Parameters of PET/MR in Patients With Head and Neck Squamous Cell Carcinoma Treated With Chemoradiotherapy

• Published in: Frontiers in oncology Vol. 10; p. 1484
• Main Authors: Kedves, András, Tóth, Zoltán, Emri, Miklós, Fábián, Krisztián, Sipos, Dávid, Freihat, Omar, Tollár, József, Cselik, Zsolt, Lakosi, Ferenc, Bajzik, Gábor, Repa, Imre, Kovács, Árpád
• Format: Journal Article
• Language: English
• Published: Frontiers Media S.A 02-09-2020
• Subjects: ADC; MTV; Oncology; PET/MR; predictive value; SUV; TLG
• ISSN: 2234-943X; 2234-943X
• DOI: 10.3389/fonc.2020.01484

Purpose:
This study aims to evaluate the predictive value of the pretreatment, metabolic, and diffusion parameters of a primary tumor assessed with PET/MR on patient clinical outcomes.
Methods:
Retrospective evaluation was performed using PET/MR image data sets acquired using the single tracer injection dual imaging of 68 histologically proven head and neck cancer patients 4 weeks before receiving definitive chemoradiotherapy (CRT). PET/MR was performed before the CRT and 12 weeks after the CRT for response evaluation. Image data (PET and MRI diffusion-weighted imaging [DWI]) was used to specify the maximum standard uptake value, the peak lean body mass corrected, SUV
max
, the metabolic tumor volume, the total lesion glycolysis (SUV
max
, SUL
peak
, MTV, and TLG), and the mean apparent diffusion coefficient (ADC
mean
) of the primary tumor. Based on the results of the therapeutic response evaluation, two patient subgroups were created: one with a viable tumor and another without. Metabolic and diffusion data, from the pretreatment PET/MR and the therapeutic response, were correlated using Spearman's correlation coefficient and Wilcoxon's test.
Results:
After completing the CRT, a viable residual tumor was detected in 36/68 (53%) cases, and 32/68 (47%) patients showed complete remission. However, no significant correlation was found between the pretreatment parameter, ADC
mean
(
p
= 0.88), and the therapeutic success. The PET parameters, SUV
max
and SUL
peak
, MTV, and TLG (
p
= 0.032,
p
= 0.01,
p
< 0.0001,
p
= 0.0004) were statistically significantly different between the two patient subgroups.
Conclusion:
This study found that MRI-based (ADC
mean
) data from FDG PET/MR pretreatment could not be used to predict therapeutic response although the PET parameters SUV
max
, SUL
peak
, MTV, and TLG proved to be more useful; thus, their inclusion in risk stratification may also be of additional value.