Fig. 4: Effect of additional rituximab in patients with a negative interim PET scan.
Overall, patients treated with two additional cycles of rituximab did not show a significantly prolonged TTP (A). An optimized mean-SUVAI threshold (SUV 4.89) was used to classify patients with a negative iPET into those with high versus low FDG uptake (B). In patients with low mean-SUVAI, TTP was not affected by additional rituximab (C). In contrast, patients with high mean-SUVAI receiving additional rituximab had significantly prolonged TTP (D). For comparison, the conventional metrics max-SUVmanual (E) and decline in SUVmax between baseline and interim PET (F) could not identify patients who had a TTP benefit in response to treatment with additional rituximab.
