Fig. 4

Emergence of the 13q12 amplicon under bevacizumab treatment in patient C216. a Genome-wide log2 ratio plots of plasma samples from C216 obtained before bevacizumab treatment (upper), after 227 days of bevacizumab treatment (middle), and after 285 days of bevacizumab treatment (bottom). The insets illustrate the respective tumor fraction (TF) for each analysis and enlarged log2 ratio plots of chromosome 13, the bottom 2 samples show gain of chromosome 13, with the highest copy number gain on chr13q12.2, the region that harbors the POLR1D gene. Copy number gains are shown in red, balanced regions in green, and copy number losses in blue. b Plot illustrating all time points of blood collection and relative marker changes. Red line: POLR1D copy number changes identified by digital PCR, showing minimum changes until day 227. Blue line: blood CEA level changes. Black line: blood CA19-9 level changes. Gray bar: tumor content identified in every sample using ichorCNA. c Four CT images obtained in 4 different time points, i.e., day 10, day 152, day 222, and day 276 after bevacizumab treatment. Compared to the first image, no significant changes were identified on day 152, during which the patient had been evaluated to have stable disease in accordance with the RECIST criteria. On day 222, the pre-present liver metastasis lesions enlarged with occurrence of new micrometastasis lesions. On day 276, all livers metastasis lesions had become larger