How is metabolic tumor volume measured?
MTV is defined as the sum of the volume of voxels with SUV surpassing a threshold value in a tumor . TLG is calculated by multiplying MTV and the mean SUV of the MTV .
What is metabolic volume?
Metabolic volume is defined as the lesion volume within a delineated boundary. Several delineation methods have been used, including. fixed threshold based on certain SUV (Im et al., 2016) relative threshold based on certain voxel SUV per SUVmax or SUVpeak.
What is tumor volume?
Listen to pronunciation. (TOO-mer VOL-yoom) The size of a cancer measured by the amount of space taken up by the tumor. For example, the tumor volume of prostate cancer is the percentage of the prostate taken up by the tumor.
How is TLG calculated?
The TLG of each focal lesion was calculated by multiplying the MTV of that lesion with its corresponding mean SUV. The global TLG of each patient was defined as the sum of the TLGs for all the focal lesions in the analysis.
What is total lesion glycolysis?
Total lesion glycolysis (TLG) is the product of mean SUV and MTV and was first introduced by Larson et al (20) to evaluate therapeutic response. It combines the volumetric and metabolic information of FDG PET. Studies have shown the usefulness of TLG for evaluating treatment response in different tumors (21–27).
How is SUVmax measured?
SUVmax is calculated as SUVmax = tracer uptake in ROI / (injected activity / patient weight). This provides a number (2, 10, 20, etc.) that conveys a sense of the relative extent of FDG uptake in a lesion.
What is a metabolic tumor?
Metabolic tumor volume (MTV) refers to the metabolically active volume of the tumor segmented using FDG PET, and has been shown to be useful in predicting patient outcome and in assessing treatment response. Also, tumor segmentation using FDG PET has useful applications in radiotherapy treatment planning.
Does tumor size determine stage?
Tumor Size and Staging
Tumor size is strongly related to prognosis (chances for survival). In general, the smaller the tumor, the better the prognosis tends to be . Tumor size is part of breast cancer staging. In the TNM staging system, a “T” followed by a number shows the size of the tumor.
Is 10mm a large tumor?
The great majority of subsequent studies have confirmed the influence of tumor size on prognosis. Most of these studies have considered small tumors to be those no larger than 10 mm in largest diameter and 2–3 mm in height.