Immunohistochemical Profile of Hodgkin and Non-Hodgkin Lymphoma.

OBJECTIVE

To analyze the frequencies of histological types of lymphoma, diagnosed with complete immunohistochemical profile in younger and older age group.

STUDY DESIGN

Cross-sectional analytical study.

PLACE AND DURATION OF STUDY

Dow Diagnostic Research and Reference Laboratory, Dow University of Health Sciences, Karachi, from January 2009 to September 2013.

METHODOLOGY

Consecutive cases of lymphomas, which were diagnosed using immunohistochemistry, were analyzed according to WHO classification. Frequency and percentages for different types of lymphomas were calculated. Hodgkin and non-Hodgkin lymphomas characteristics in two age groups of less than and more than 40 years were compared, applying chi-square test.

RESULTS

Out of the 318 cases, 79 (25%) were Hodgkin Lymphomas (HL) and 239 (75%) were Non-Hodgkin Lymphomas (NHL). Mixed Cellularity Hodgkin Lymphoma (MCHL) was the commonest (n=48). Amongst the NHL, 215 (89.95%) were B cell lymphomas and 24 (10.05%) were T-cell lymphomas. Diffuse Large B-Cell Lymphoma (DLBCL) was the commonest lymphoma (n=165, 69.95% of NHL). Anaplastic T-Cell Lymphoma (ALCL, n=10) was the commonest T-cell lymphoma. The frequency of HLwas significantly higher in the younger age group and that of NHLwas higher in the older age group (p < 0.001). Primary lymph node involvement was reported in 175 (55%) and cervical lymph node was the most frequent site. Extra nodal involvement was seen in 93 (29%) of all cases and was reported in 87 (36.4%) of NHLand 6 (7.5%) of HL. The most common extra nodal site was the gastrointestinal tract.

CONCLUSION

Hodgkin lymphoma comprises 25% and non-Hodgkin lymphoma comprises 75% of all lymphomas. Both occur in younger age groups than reported in the West. B-cell NHLis three times more common than T-cell lymphoma. DLBCLis the most frequent lymphoma. ALCLis the most common T-cell, and mixed cellularity is the most common Hodgkin lymphoma.