The correlation between interim imaging results and disease prognosis of patients with Hodgkin and diffuse large B cell lymphoma: single center experience

Objective: This study aims to explore the relationship between interim imaging outcomes and disease prognosis in patients diagnosed with Hodgkin lymphoma (HL) and diffuse large B-cell lymphoma (DLBCL).Method: A total of 157 patients were retrospectively analyzed, comprising 90 with DLBCL and 67 with HL, who received follow-up at our institution. Interim and baseline PET/CT scans (I-PET/CT) from 121 patients were independently interpreted by two nuclear medicine specialists, blinded to clinical data. Additionally, 53 patients underwent both initial and interim contrast-enhanced computed tomography (I-CT), which was independently reviewed by two radiologists under blinded conditions. Results: Interim PET/CT findings were analyzed in relation to post-treatment outcomes to determine the predictive performance of the imaging modality. The positive predictive value (PPV) and negative predictive value (NPV) were calculated separately for HL and DLBCL. In HL cases, I-PET/CT demonstrated a PPV of 36% and an NPV of 95.4%, while in DLBCL, the respective values were 61.9% and 93.1%. Notably, among patients assessed with both PET/CT and I-CT, 2 individuals in the DLBCL group exhibited negative I-CT results despite positive I-PET/CT findings. Conversely, 3 HL patients showed positive I-CT findings despite negative I-PET/CT.Conclusion: PET/CT provided a substantial advantage in evaluating therapeutic response over conventional CT, reducing the risk of overtreatment in early-stage disease and undertreatment in more advanced stages. Interim PET/CT negativity was found to be a strong indicator of favorable progression-free survival outcomes, potentially guiding clinicians toward more individualized and less intensive treatment strategies. Nevertheless, confirmation of these findings through prospective randomized trials remains essential.