@Zander the reason for this is because series 9 is a diffusion-weighted image, and most likely the series is a 4-dimensional trace image, where 4th dimension corresponds to the b-value for a given trace image, and there are apparently 5 b-values in that series.
You can see this by observing how the slice location annotation does not change for 5 slices (red arrow below), which means they correspond to the same spatial location.
For the sake of completeness, the study in question is here: https://viewer.imaging.datacommons.cancer.gov/viewer/1.3.6.1.4.1.14519.5.2.1.1706.4001.145725991542758792340793681239. Going forward, referencing the specific study is helpful for debugging of the issue. The IDC Viewer URL uses StudyInstanceUID
, which is persistent, and can be used to uniquely identify the study in IDC.