Implications of the partial volume effect correction on the spatial quantification of hypoxia based on [¹⁸F]FMISO PET/CT data

Autores de IIS La Fe

• Montserrat Carles Fariña

  Autor

Participantes ajenos a IIS La Fe

• Kafkaletos, Athanasios
• Sachpazidis, Ilias
• Mix, Michael
• Schaefer, Henning
• Ruehle, Alexander
• Nicolay, Nils H.
• Lazzeroni, Marta
• Toma-Dasu, Iuliana
• Grosu, Anca L.
• Baltas, Dimos

Grupos

• Investigacion Biomédica en Imagen (GIBI 2-30)

  Investigador Principal

  Leonor Cerdá Alberich

Abstract

Purpose: This study evaluates the impact of partial volume effect (PVE) correction on [F-18]fluoromisonidazole (FMISO) PET images, focusing on the conversion of standardized uptake values (SUV) to partial oxygen pressure (pO(2)) and the subsequent determination of hypoxic tumor volume (HTV). Methods: FMISO PET images from 49 head and neck squamous cell carcinoma cases were retrospectively corrected for PVE and converted to pO(2). A pO(2) threshold of 10 mmHg was used to delineate the HTV (HTVpO2). Comparisons of pO(2) distribution and HTVpO2 between corrected and uncorrected images were made, with pO(2) distributions evaluated against published polarographic data. HTVpO2 was compared to HTV defined by the conventional tumor-to-muscle ratio (TMR) method (HTVTMR) in terms of volume and topography (DICE coefficient, Hausdorff distance, and center-of-gravity distance) across different TMR cutoff levels. The cutoff level where the segmentation results from both methods were most similar was identified (TMRbest). Results: The PVE correction led to decreased minimum pO(2), increased HTVpO2 and the identification of more hypoxic cases (HTV > 0). The pO(2) distribution demonstrated improved alignment with published polarographic data. At TMRbest 1.6, the center-of-gravity distance between HTVTMR and HTVpO2 demonstrated a low median at 1.5 mm, while the wide range (0.0 to 9.6 mm) indicated high interpatient variability. The shape of HTV exhibited considerable variation with DICE 0.74 (0.03 to 1.00) and Hausdorff distance 8.5 mm (2.0 to 42.8 mm). Conclusions: PVE correction is recommended before converting SUV to pO(2) for the spatially resolved quantification of hypoxia

Keywords

• Hypoxia; Partial volume effect; PET; FMISO; HNSCC