PET/CTimproves the definition of complete response and allows to detect otherwise unidentifiable skeletal progression in multiple myeloma
Menée sur 282 patients atteints d'un myélome multiple symptomatique traité entre 2002 et 2012 (durée médiane de suivi : 67 mois), cette étude montre qu'une tomographie numérique par émission de positrons permet d'améliorer l'évaluation de la réponse complète au traitement et de mettre en évidence une progression osseuse de la maladie
Purpose : To evaluate the role of 18F-FDG PET/CT in 282 symptomatic MM pts treated up-front between 2002 and 2012.
Experimental design : All pts were studied by PET/CT at baseline, during post-treatment follow-up and at the time of relapse. Their median duration of follow-up was 67 months.
Results : Forty-two percent of the pts at diagnosis had > 3 FLs and in 50% SUVmax was > 4.2; EMD was present in 5%. On multivariate analysis, ISS 3, SUVmax > 4.2 and failure to achieve best CR were the leading factors independently associated with shorter PFS and OS. These 3 variables were used to construct a prognostic scoring system based on the number of risk factors. After treatment, PET/CT negativity (PET-neg) was observed in 70% of pts, while conventionally-defined CR was achieved in 53%. Attainment of PET-neg favourably influenced PFS and OS. PET-neg was an independent predictor of prolonged PFS and OS for patients with conventionally-defined CR. Sixty-three percent of pts experienced relapse or progression; in 12% skeletal progression was exclusively detected by systematic PET/CT performed during follow-up. A multivariate analysis revealed that persistence of SUVmax > 4.2 following first-line treatment was independently associated with exclusive PET/CT progression.
Conclusions : PET/CT combined with ISS stage and achievement or not of CR on first-line therapy sorted pts into different prognostic groups. PET/CT led to a deeper evaluation of CR. Finally, in pts with persistent high glucose metabolism after first-line treatment, PET/CT can be recommended during follow-up, to screen for otherwise unidentifiable progression.
Clinical Cancer Research , résumé, 2015