Ziel/Aim Automatic quantification of the metabolic tumor volume (MTV) from PET data by neural
networks can simplify the clinical implementation of the parameter, whose manual estimation
is a laborious process. It remains unclear how specific a neural network has to be
designed for the investigated disease. The aim of this study was to evaluate the accuracy
of a neural network that was trained on lymphoma and lung cancer FDG PET/CT data in
the evaluation of breast cancer patients.
Methodik/Methods F-18-FDG PET/CT data sets of 50 breast cancer patients were included. The PARS neural
network (Siemens) was used to detect pathological foci and determine their anatomical
location. The PARS network was developed on lymphoma and lung cancer PET data. For
diagnostic reference consensus reads of two nuclear medicine physicians and follow
up data were used. In total 1072 foci were manually segmented. The accuracy was calculated
for lesion detection, MTV quantification, and anatomical position determination.
Ergebnisse/Results For PERCIST measurable foci, the per patient sensitivity and specificity of the neural
network for lesion detection was high (92 %,CI = 79-97 % and 98 %,CI = 94-99 %). Extending
the analysis to all FDG-avid foci, the sensitivity decreased (39 %,CI = 30-50 %).
A high correlation was observed between the AI derived and the manually segmented
MTV (R2=0.91;p < 0.001). The anatomical position determination was accurate on the body part
(98 %;CI = 95-99 %), region (88 %;CI = 84-90 %) and subregion level (79 %;CI = 74-84 %).
Moreover, the AI-derived whole-body MTV was a significant prognosticator for overall
survival (HR = 1.275;CI = 1.208-1.713;p < 0.001). In a multivariate analysis, also
the AI-derived lymph node MTV (HR = 1.190;CI = 1.022-1.384; p = 0.025) and liver MTV
(HR = 1.149; CI = 1.001-1.318; p = 0.048) were predictors for overall survival.
Schlussfolgerungen/Conclusions The neural network that was trained on lymphoma and lung cancer data displayed a
high sensitivity and specificity for the detection of PERCIST measurable lesions and
a high accuracy in anatomical position determination in FDG PET/CT data from breast
cancer patients. Nevertheless, the whole body MTV was a significant predictor for
overall survival.