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Purpose: This study investigated two fixed threshold methods to delineate the target volume using (18)FDG PET/CT before and during a course of radical radiotherapy in locally advanced squamous cell carcinoma of the head and neck.
Materials And Methods: Patients were enrolled into the study between March 2006 and May 2008. (18)FDG PET/CT scans were carried out 72h prior to the start of radiotherapy and then at 10, 44 and 66Gy. Functional volumes were delineated according to the SUV Cut Off (SUVCO) (2.5, 3.0, 3.5, and 4.0bwg/ml) and percentage of the SUVmax (30%, 35%, 40%, 45%, and 50%) thresholds. The background (18)FDG uptake and the SUVmax within the volumes were also assessed.
Results: Primary and lymph node volumes for the eight patients significantly reduced with each increase in the delineation threshold (for example 2.5-3.0bwg/ml SUVCO) compared to the baseline threshold at each imaging point. There was a significant reduction in the volume (p⩽0.0001-0.01) after 36Gy compared to the 0Gy by the SUVCO method. There was a negative correlation between the SUVmax within the primary and lymph node volumes and delivered radiation dose (p⩽0.0001-0.011) but no difference in the SUV within the background reference region. The volumes delineated by the PTSUVmax method increased with the increase in the delivered radiation dose after 36Gy because the SUVmax within the region of interest used to define the edge of the volume was equal or less than the background (18)FDG uptake and the software was unable to effectively differentiate between tumour and background uptake.
Conclusions: The changes in the target volumes delineated by the SUVCO method were less susceptible to background (18)FDG uptake compared to those delineated by the PTSUVmax and may be more helpful in radiotherapy planning. The best method and threshold have still to be determined within institutions, both nationally and internationally.
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http://dx.doi.org/10.1016/j.radonc.2010.04.025 | DOI Listing |
Comput Methods Programs Biomed
August 2025
The Institute of Cancer Research, London, UK. Electronic address:
Background And Objective: Apparent Diffusion Coefficient (ADC) values and Total Diffusion Volume (TDV) from Whole-body diffusion-weighted MRI (WB-DWI) are recognised cancer imaging biomarkers. However, manual disease delineation for ADC and TDV measurements is unfeasible in clinical practice, demanding automation. As a first step, we propose an algorithm to generate fast and reproducible probability maps of the skeleton, adjacent internal organs (liver, spleen, urinary bladder, and kidneys), and spinal canal.
View Article and Find Full Text PDFAnn Surg Oncol
September 2025
HepatoBiliaryPancreatic Surgery, AOU Careggi, Department of Experimental and Clinical Medicine (DMSC), University of Florence, Florence, Italy.
Purpose: To build computed tomography (CT)-based radiomics models, with independent external validation, to predict recurrence and disease-specific mortality in patients with colorectal liver metastases (CRLM) who underwent liver resection.
Methods: 113 patients were included in this retrospective study: the internal training cohort comprised 66 patients, while the external validation cohort comprised 47. All patients underwent a CT study before surgery.
J Appl Clin Med Phys
September 2025
Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Clinical Research Center for Radiation Oncology, Shanghai Key Laboratory of Radiation Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
Purpose: This study aims to assess percentage of automated AIO plans that met clinical treatment standards of radiotherapy plans generated by the fully automated All-in-one (AIO) process.
Methods: The study involved 117 rectal cancer patients who underwent AIO treatment. Fully automated regions of interest (ROI) and treatment plans were developed without manual intervention, comparing them to manually generated plans used in clinical practice.
NMR Biomed
October 2025
Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA.
Understanding gastric physiology in rodents is critical for advancing preclinical neurogastroenterology research. However, existing techniques are often invasive, terminal, or limited in resolution. This study aims to develop a non-invasive, standardized MRI protocol capable of capturing whole-stomach dynamics in anesthetized rats with high spatiotemporal resolution.
View Article and Find Full Text PDFSci Rep
September 2025
Center for Northeast Asian Studies, Tohoku University, 41 Kawauchi, Sendai Aoba-ku, Miyagi, 980-8576, Japan.
Petit-spot volcanism plays a critical role in the metasomatism of oceanic plates prior to subduction and in their recycling into the deep mantle. The extent of metasomatism depends on the number and volume of petit-spot volcanic edifices and intrusions, making precise identification of petit-spot volcanic fields essential. However, conventional methods based on seafloor topography and acoustic backscatter intensity alone have limitations in accurately delineating these features.
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