Prognostic Significance of Interim PET/CT in the First-Line Treatment of Follicular Lymphoma Patients, a Single-Center Experience.

: Follicular lymphoma (FL) is a heterogeneous disease, and identifying high-risk patients early is crucial for optimal management. This study aimed to evaluate the prognostic significance of interim positron emission tomography/computed tomography (PET/CT) in newly diagnosed FL patients undergoing first-line treatment. : This single-center, retrospective study included 103 patients with newly diagnosed FL who underwent interim PET/CT. The primary endpoint was progression-free survival (PFS). The prognostic value of positive interim PET/CT, Deauville scores, and maximum standardized uptake values (SUVmax) were analyzed among other clinical features. : A total of 30 patients (29.1%) were deemed interim PET/CT-positive. The interim PET/CT-positive group demonstrated a significantly shorter median PFS compared to the interim PET/CT-negative group (17 months vs. not reached, respectively; < 0.0001). Similarly, patients with Deauville scores of 1-3 had better PFS, with median survival not yet reached, while those with higher Deauville scores exhibited poorer progression-free survival and a median survival of 18 months. Notably, patients with an interim PET/CT SUVmax exceeding 3.365 experienced significantly shorter median survival compared to those with lower values. : Our findings support the use of interim PET/CT as a prognostic tool in FL. These results are consistent with other studies, although some debate exists regarding the optimal PET/CT metric. Further research is needed to validate these findings and explore personalized treatment strategies based on interim PET/CT results.