Page 39 - Wondergem

18F-FDG or 18F-FLT to detect transformation
of a previously stable lymph node). The remaining 11 FL patients reached CR on CT scan
after chemo-immunotherapy, with a median response duration of 30 months (range
14-43). All FL patients were alive at last follow-up.
Eight out of nine TF patients reached CR on PET-CT after induction therapy, seven of 2 whom were eligible for consolidation with autologous stem cell transplantation. Of
these seven patients only one patient relapsed after 30 months. The patient without consolidation died of secondary acute myeloid leukemia 34 months after her treatment. In the single patient who obtained a partial remission (PR) only on PET-CT after induction therapy, the autologous stem cell transplantation did not result in an improvement of response, and progression occurred 3 months after transplant eventually leading to death. Median PFS and OS for TF patients were both 29 months. (table 1).
For either tracer, the mean uptake interval between injection and image acquisition was 61 minutes (SD 7.9 min). During 18F-FDG PET examination, serum glucose levels ranged from 5.4 to 7.2 mmol/l, except in one diabetic TF patient who had a plasma glucose level of 16 mmol/l.
The number of visually positive lymph nodes was similar for 18F-FDG and 18F-FLT PET. We measured SUV of 259 lymph nodes in the 26 patients (median 9 per patient, range 2-23). Since results of the various SUV metrics were highly concordant for either tracer: r=0.99, p<0.01, we only report the SUVmax based data. SUV A50% can be inferred by multiplying SUVmax by 0.68.
In individual patients, the most avid lymph node was the same for 18F-FDG and 18F-FLT in only 42% (11 out of 26 patients; 5 FL and 6 TF) .
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