Introduction: The diagnosis of nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) and T

cell/histiocyte-rich large B-cell lymphoma (THRLBCL) can be diffificult due to their overlapping histological features. Recently, insulin-like growth factor II mRNA-binding protein 3 (IMP3) has been proposed as a diagnostic marker for Hodgkin’s lymphoma. The objective of this study was to evaluate the effectiveness of IMP3 in differentiating between NLPHL and THRLBCL.

Methods: This was a retrospective study that included formalin-fifixed paraffifin-embedded blocks from 56 patients. Of these, 28 were diagnosed with NLPHL and 28 with large B cell lymphoma (LBCL), including 16 THRLBCL and 12 DLBCL, NOS, based on immunohistochemistry (IHC). Samples were stained for IMP3 using IHC, and positive expression was defifined as moderate to strong staining in at least 10% of tumor cells.

Results: The mean age of the patients was 41.25 ± 16.08 years, and the majority were male. There was a signifificant age difference between NLPHL (34.61 ± 16.44 years) and LBCL (47.89 ± 12.85 years) groups (p = 0.001). No signifificant difference was observed in gender or site between NLPHL and LBCL groups. The expression of IMP3 was mainly strong in the LBCL group, while it was heterogeneously distributed among NLPHL samples, ranging from weak to strong (p < 0.001). It was determined that strong IMP3 expression at 55.00% can differentiate LBCL from NLPHL with 71.4% sensitivity and 71.4% specifificity.

Conclusion: Our fifindings showed that IMP3 may be a good complement in differentiating NLPHL cases from THRLBCL.