We compute the NL -method LOD thresholds for spurious hotspot size thresholds ranging from 1 to the N -method threshold.
Past studies have however mainly focused on the task of applying appropriate methods for ranking locations, with few focusing on the issue of how to define selection methods or threshold rules for hotspot identification.
Furthermore, the results of the NSMC test performed before or after removal of the CpG sites did not depend on the threshold used for hotspot identification (Additional file 2).
It is therefor unclear what threshold for automatic hotspot identification and segmentation that is optimal in order to generate hotspots that best reflect true tumor burden.
Based on our results, using SUV 15 as a threshold for automatic hotspot segmentation reflects less tumor burden than BSI, despite the higher sensitivity of NaF PET/CT compared to bone scan.
For this purpose, SVM and multi-threshold techniques are explored for hotspot detection.
The hotspot on chromosome 7 was significant up to size 499, and the hotspot on chromosome 15 (higher peak) was significant for hotspot sizes 2 129 and 132 143.
For each individual patient first, an optimal SUV threshold for detection of hotspots was selected, based on the visual interpretation of a nuclear medicine specialist who was blinded to the patients' bone scans, BSI values, and survival data.
In this example the N-method was unable to detect any hotspots, whereas the Q-method detected false hotspots on chromosomes 3, 6, 8, 9, 12, and 16. Figure 1, B and C, shows the hotspot size null distributions and the 5% significance thresholds for the N- and Q-methods, respectively.
There are different thresholds for different violations".
