TY  - JOUR
AU  - Kafkaletos, Athanasios
AU  - Sachpazidis, Ilias
AU  - Mix, Michael
AU  - Carles, Montserrat
AU  - Stoian, Raluca
AU  - Schäfer, Henning
AU  - Bock, Michael
AU  - Baltas, Dimos
AU  - Grosu, Anca L
TI  - Surrogating tumour cell density in head and neck cancer: [18F]FDG PET- versus ADC (MRI)-based approaches.
JO  - Radiation oncology
VL  - 20
IS  - 1
SN  - 1748-717X
CY  - London
PB  - BioMed Central
M1  - DKFZ-2025-01823
SP  - 137
PY  - 2025
AB  - In this study we examined the correlation between standardized uptake value (SUV) of [18F]fluorodeoxyglucose (FDG) and apparent diffusion coefficient (ADC) within the gross tumor volume (GTV) of patients with head and neck squamous cell carcinoma (HNSCC). In addition, we assessed the comparability of cell density (ρ) estimates obtained from FDG PET and MRI data.Twenty-one HNSCC patients from a prospective FMISO imaging trial underwent pre-treatment PET/CT and MRI. We assessed correlations between FDG SUV (mean, max) and ADC (mean, min) within the GTV using Pearson's correlation coefficient. The tumor cell density within the GTV was calculated from FDG SUV and from ADC maps. For the estimation of ADC-based cell density, we used a published tumor cell volume fraction (vTC). Agreement between FDG- and ADC-derived cell density estimates was assessed. The best-fitting vTC* was computed to achieve equal mean ρADC and ρFDG for each patient and was compared to the literature.The SUV and ADC metrics showed up to moderate negative correlations, but none of them were statistically significant at p < 0.05. The correlation of SUVmean vs. ADCmean with Pearson's correlation coefficient r = -0.426 and p = 0.054 and SUVmax vs. ADCmin with r = -0.414 and p = 0.062 suggested a weak negative trend. The average and standard deviation of mean ρFDG and ρADC across our cohort were (1.8 ± 0.6) × 108 cells/ml and (3.3 ± 0.2) × 108 cells/ml. The difference between the mean ρFDG and ρADC was statistically significant (p < 0.001). To achieve equal mean ρADC and ρFDG for each patient, the mean optimal vTC* with standard deviation was 0.29 ± 0.09. Although significantly lower than the published mean vTC​ (0.54), vTC* lies within the published range of vTC for HNSCCs (0.28 to 0.75).ADC and SUV metrics exhibited moderate but marginally insignificant correlation in this dataset. Although not directly interchangeable, the two methods provide comparable, clinically relevant cell density estimates, offering flexibility to use the most accessible modality for individualized treatment planning.Registered at German Clinical Trials Register on 20/08/2015 (DRKS00003830).
KW  - Humans
KW  - Fluorodeoxyglucose F18
KW  - Head and Neck Neoplasms: pathology
KW  - Head and Neck Neoplasms: diagnostic imaging
KW  - Male
KW  - Middle Aged
KW  - Female
KW  - Radiopharmaceuticals
KW  - Aged
KW  - Prospective Studies
KW  - Squamous Cell Carcinoma of Head and Neck: diagnostic imaging
KW  - Squamous Cell Carcinoma of Head and Neck: pathology
KW  - Magnetic Resonance Imaging: methods
KW  - Positron Emission Tomography Computed Tomography: methods
KW  - Positron-Emission Tomography: methods
KW  - Adult
KW  - Diffusion Magnetic Resonance Imaging: methods
KW  - Tumor Burden
KW  - ADC (Other)
KW  - Cell density (Other)
KW  - FDG (Other)
KW  - HNSCC (Other)
KW  - Fluorodeoxyglucose F18 (NLM Chemicals)
KW  - Radiopharmaceuticals (NLM Chemicals)
LB  - PUB:(DE-HGF)16
C6  - pmid:40890739
DO  - DOI:10.1186/s13014-025-02716-6
UR  - https://inrepo02.dkfz.de/record/304283
ER  -