All patients underwent a CT scan within 2 months before the immunotherapy treatment start date. When available, follow-up CT scans were acquired within 4 months after treatment (up to three temporal time points per patient). All CT images were acquired after contrast injection during a patient inspiratory breath hold, following the contrast-enhanced CT chest protocol. CT scans were reconstructed using a standard kernel. A description of CT parameters is available in Additional file 1 : Table S3.
For each case, the primary tumor was selected as the target lesion. 3D tumors were identified and segmented by an experienced radiologist on the baseline and follow-up CT images using either the syngo.via Siemens Healthineers software or 3D Slicer [23 (link)]. The largest lesion was considered if a patient had an ambiguous primary tumor. Follow-up CT scans were discarded if the tumor found in the baseline CT scan was no longer visible.
For pre-processing, Hounsfield units of all CT images were clipped between -1000 and 3050, and z-score normalization was then applied.
For each case, the primary tumor was selected as the target lesion. 3D tumors were identified and segmented by an experienced radiologist on the baseline and follow-up CT images using either the syngo.via Siemens Healthineers software or 3D Slicer [23 (link)]. The largest lesion was considered if a patient had an ambiguous primary tumor. Follow-up CT scans were discarded if the tumor found in the baseline CT scan was no longer visible.
For pre-processing, Hounsfield units of all CT images were clipped between -1000 and 3050, and z-score normalization was then applied.
Free full text: Click here
