Different Role of PET‐CT Evaluation in Newly Diagnosed Follicular Lymphoma Upon Rituximab‐Based Chemotherapy and Chemo‐Free Immunotherapy

ABSTRACT Newly diagnosed follicular lymphoma (FL) patients usually received first‐line rituximab‐based immunochemotherapy (R‐chemo). Recently, rituximab plus lenalidomide (R2) emerged as an alternative chemo‐free immunotherapy. We performed a comparative analysis of positron emission tomography/computed tomography (PET/CT) in FL undergoing R‐chemo or R2. With data of sequential PET/CT at the baseline, interim, and end‐of‐induction, treatment responses and survival outcomes were analyzed using Deauville scores at the interim and end‐of‐induction. Additionally, correlations between interim Deauville scores and baseline PET/CT parameters were explored. Conclusively, we revealed that Deauville 1–3 at the interim and end‐of‐induction showed lower disease progression within 24 months (POD24) and superior progression‐free survival (PFS) in R‐chemo and R2 cohorts. Also, patients with interim Deauville 1–3 exhibited reduced POD24 and favorable PFS as compared to those with interim Deauville 4–5/end‐of‐induction Deauville 1–3. Furthermore, total lesion glycolysis of baseline PET‐CT surpassed standardized uptake value and total metabolic tumor volume in predicting interim Deauville 1–3, with different optimal cutoffs of 2600 and 600 mL in the R‐chemo and R2 cohort. These findings underscored the potential of PET‐CT‐adapted strategies to achieve durable remission in FL undergoing rituximab‐based immunochemotherapy or immunotherapy.