The Prognostic Value of Total Tumor Volume Response Compared With RECIST1.1 in Patients With Initially Unresectable Colorectal Liver Metastases Undergoing Systemic Treatment

Objectives: Compare total tumor volume (TTV) response after systemic treatment to Response Evaluation Criteria in Solid Tumors (RECIST1.1) and assess the prognostic value of TTV change RECIST1.1 for recurrence-free survival (RFS) patients with colorectal liver-only metastases (CRLM). Background: provides unidimensional criteria evaluate therapy. Those are accepted worldwide but limited by interobserver variability ignore potentially valuable information about TTV. Methods: Patients initially unresectable CRLM receiving from randomized, controlled CAIRO5 trial (NCT02162563) were included. was assessed using software specifically developed together SAS analytics. Baseline follow-up computed tomography (CT) scans used calculate Different thresholds (10%, 20%, 40%) define as no standard currently exists. RFS a subgroup secondarily resectable induction treatment. Results: A 420 CT comprising 7820 210 evaluated. In 30% 50% (depending on chosen threshold) patients, discordance observed between change. decrease >40% 47 (22%) who had stable disease according RECIST1.1. 118 CRLM, shorter less than 10% compared more (P = 0.015), while not 0.821). Conclusions: assessment shows potential evaluation therapy CRLM.