End of induction [18F]FDG PET is prognostic for progression-free survival and overall survival in follicular lymphoma patients enrolled in the FOLL12 trial

• Published in: European journal of nuclear medicine and molecular imaging 2024-09, Vol.51 (11), p.3311-3321
• Main Authors: Guerra, Luca, Chauvie, Stephane, Fallanca, Federico, Bergesio, Fabrizio, Marcheselli, Luigi, Durmo, Rexhep, Peano, Simona, Franceschetto, Antonella, Monaco, Lavinia, Barbieri, Emiliano, Ladetto, Marco, Musuraca, Gerardo, Tosi, Patrizia, Bianchi, Benedetta, Bolis, Silvia Anna Maria, Pavone, Vincenzo, Chiarenza, Annalisa, Arcari, Annalisa, Califano, Catello, Bari, Alessia, Massaia, Massimo, Conconi, Annarita, Musto, Pellegrino, Mannina, Donato, Roti, Giovanni, Galimberti, Sara, Gini, Guido, Falcinelli, Flavio, Vitolo, Umberto, Usai, Sara Veronica, Stefani, Piero Maria, Ibatici, Adalberto, Liberati, Anna Marina, Pennese, Elsa, Perrone, Tommasina, Versari, Annibale, Luminari, Stefano
• Format: Article
• Language: English
• Subjects: Cardiology; Evaluation; Fluorine isotopes; Imaging; Lymphoma; Medicine; Medicine & Public Health; Metabolic response; Metabolism; Nuclear Medicine; Oncology; Original Article; Orthopedics; Positron emission; Positron emission tomography; Radiology; Rituximab; Survival
• ISSN: 1619-7070; 1619-7089
• DOI: 10.1007/s00259-024-06765-z

Purpose To evaluate the reliability of the Deauville score (DS) in therapy response assessment and to define the prognostic value of the metabolic response of end of induction (EOI) [ 18 F]FDG PET (PET) in follicular lymphoma patients. Methods Adult patients with untreated grade 1–3a FL/ stage II‐IV enrolled in the multicentre, prospective, phase III FOLL12 trial (NCT02063685) were randomized to receive standard immunochemotherapy followed by rituximab maintenance (standard arm) versus standard immunochemotherapy followed by response-adapted post‐induction management (experimental arm). Baseline and EOI PET were mandatory for the study. All PET scans were centralized on the WIDEN® platform and classified according to DS in a blind independent central review. DS1–3 was considered negative (CMR), whereas DS4‐5 was considered positive (not CMR). The primary endpoint was PFS. The main secondary endpoint was overall survival (OS). Results Overall, 807 follicular lymphoma patients—52% women, 89% stage III-IV disease, 40% with a high-risk FLIPI-2 score (3–5)—were enrolled in the study; 729 (90.4%) baseline and EOI PET were available for the analysis. EOI PET was positive (DS4–5) in 88/729 (12.1%) cases. Overall inter-reviewer agreement on PET pos/neg result was 0.92, while agreement on positive and negative cases was 0.77 and 0.94, respectively. The median follow-up was 69 months; 247 events were registered in the 5-yr follow-up, with a 5-yr PFS of 67% (95%CI: 63%–70%). The 5-yr PFS rate for PET neg (DS1–3) and PET pos (DS4–5) patients was 71% (95%CI: 67%–75%) and 36% (95%CI: 25%–46%), respectively, with HR 3.49 (95%CI: 2.57–4.72). Five-year PFS was worse as DS increased, with 74% (70%–78%), 58% (48%–67%; HR 1.71; p = 0.001)] and 36% (25%–46%; HR 3.88; p