Value of Early Evaluation with FDG-PET for Follicular Lymphoma.

Objective: evaluate the predictive value of the FDG-PET on the evolution of Follicular lymphomas.

Methods: FDG-PET was performed in 17 consecutive patients treated for follicular lymphoma during the course of their treatment (ttt): 8 were evaluate early (Ea) after the second course of chemotherapy (CT) and 9 later (La) after the third course (5 pts) or the fourth (4 pts). 9 were treated at diagnosis and 8 at relapse. 15 histologic grade 1–2 received 6 courses of Rituximab-VAD-Chlorambucil (n=13) or R-miniCHVP (n=2) and two grade 3 a R-CHOP like regimen. 12 were intensified with haematopoietic stem cell transplantation (10 auto, 2 allo). 6 were Flipi 0–1, 3 Flipi 2 and 8 Flipi 3–4.

Results:

Among the 8 Ea, only 3 negativate their FDG-PET, 4 had a minimal uptake and one remained positive (he relapsed 2 months after the completion of their ttt). 4/4 pts with minimal uptake became negative after the completion of the ttt. 7/7 negative pts remained relapse free (Median Fup 17 months).

Among the 9 La, 8 were negative (5/5 after the third course) and one had a residual uptake after the fifth course (he died disease free from non haematolgical cause). One/8 negative patient have relapsed 5 months after ttt, 7 are alive and disease free. The 2 histologic grades 3 were Ea. Negative. Flipi 0–1(n=6) or Flipi 2 (n=3) were all negative. The Ea. Positive and the La. Residual were Flipi 3.

Conclusion

The best time of evaluation for the follicular lymphoma might be later than for High grade and might be proposed after three courses of chemotherapy when associated with rituximab. The Flipi seems to be correlated to the FDG-Pet response. These preliminary results are encouraging to define the predictive value of FDG-PET for follicular lymphoma survival, especially for the flipi 3.