IMMUNOPROFILE OF HODGKIN LYMPHOMA AND EXPRESSION OF IMP3 IN CLASSICAL HODGKIN LYMPHOMA, NODULAR LYMPHOCYTE-PREDOMINANT HODGKIN LYMPHOMA AND DIFFUSE LARGE B-CELL LYMPHOMA

Abstract

Background: Accurate distinction among classical Hodgkin lymphoma (cHL), nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), and diffuse large B-cell lymphoma (DLBCL) may be challenging because of overlapping morphologic and immunophenotypic features. This study evaluated the immunoprofile of Hodgkin lymphoma and assessed insulin-like growth factor II mRNA-binding protein 3 (IMP3) expression across cHL, NLPHL, and DLBCL. Methods: A retrospective and prospective study was conducted over a two-year period at Madras Medical College/Rajiv Gandhi Government General Hospital. Fifty specimens were included: 25 cHL, 2 NLPHL, and 23 DLBCL. Histopathological sections were reviewed and immunohistochemistry was performed using CD3, CD20, CD15, CD30, and IMP3. Categorical variables were assessed using chi-square/Fisher exact tests as appropriate, with P<0.05 considered statistically significant. Results: The study included 37 males and 13 females; 41 cases were nodal and 9 were extranodal. Among cHL cases, mixed cellularity was the predominant subtype (22/25, 88%). CD15 and CD30 were positive in 22/25 (88%) and 25/25 (100%) cHL cases, respectively. IMP3 showed cytoplasmic positivity in 20/25 (80%) cHL cases, 2/2 (100%) NLPHL cases, and 18/23 (78.3%) DLBCL cases based on the detailed subgroup counts in the study results. These findings indicate that IMP3 positivity occurs in both Hodgkin and large B-cell lymphomas and therefore does not reliably distinguish cHL/NLPHL from DLBCL. Conclusion: IMP3 may serve as a supplementary immunohistochemical marker because of its cytoplasmic staining in Hodgkin/Reed-Sternberg or lymphocyte-and-histiocyte cells with relatively limited background staining. However, its expression in DLBCL limits its discriminatory value. Larger studies with standardized scoring and validated antibody protocols are required.