Synchronization of Working Formulation and WHO Classification 2008 for Nodal Non-Hodgkin’s Lymphoma

Abstract

Introduction:  In Pakistan, nodal Non Hodgkin s Lymphoma (NHL) cases are being reported according to Working Formu-lation (WF). A new and broader classification of lymphomas has been introduced by WHO classification 2008 which inclu-des immunohistochemical markers and cytogenetics of these tumors. This study was carried out to synchronize WF and 2008 WHO classification of nodal NHL.

Materials and Methods:  This study was done on 50 consecutive diagnosed cases of nodal NHL. The paraffin blocks of these cases were retrieved from laboratory. New sections were cut and immunohistochemical staining was carried out on these sections.

Results:  These results showed that small lymphocytic lymphoma (SLL) according to WF have been recategorised into (WHO) SLL-T cell and SLL-B cell. Diffuse Large cell lymphoma (WF) classified into (WHO) Diffuse large B cell NOS, Peripheral T cell NOS, Anaplastic large cell lymphoma and Angioimmunoblastic lymphoma. Lymphoblastic lymphoma (WF) revealed T lymphoblastic and B lymphoblastic lymphoma types (WHO). The small cleaved, mixed and large subtypes of follicular lymphoma (WF) have been merged as follicular lymphoma(WHO). Diffuse large B cell lymphoma NOS (WHO) includes immunoblastic lymphoma (WF), diffuse mixed (WF), and some cases of diffuse large cell lymphoma (WF) in this study.

Conclusion:  The classification of lymphomas has always been a debatable issue for the pathologists and oncologists. Despite of this disparity, WF classification of lymphomas is still being used in Pakistan. However, a revised unified classi-fication would be a better step towards enhanced understanding in this field.

Key Words:  Non-Hodgkin's, lymphoblastic, immunoblastic, anaplastic.