Molecular diagnosis of Hodgkin lymphoma

Hodgkin lymphoma (HL) is a neoplasm derived from B cells, in which the unique cellular microenvironment plays an important role in accurate diagnosis and pathobiology. HL is frequently diagnosed in patients in their ۲۰s and ۳۰s, who typically exhibit lymphadenopathy above the diaphragm and may also experience systemic B symptoms. Since ۲۰۰۴, the World Health Organization has categorized Hodgkin lymphoma into two main types in their Classification of Tumours of Haematopoietic and Lymphoid Tissues. The most common form, classic Hodgkin lymphoma (CHL), makes up about ۹۰% of cases and is further divided into four subtypes: nodular sclerosis (NSCHL), mixed cellularity (MCCHL), lymphocytic rich (LRCHL), and lymphocyte-depleted (LDCHL). In contrast, nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) accounts for approximately ۱۰% of cases. This distinction is based on the specific cellular characteristics of each subtype; CHL is characterized by Hodgkin and Reed-Sternberg (HRS) cells, while NLPHL primarily features lymphocyte-predominant cells (LP). NLPHL is distinguished by its preserved B cell features when compared to CHL. Some researchers suggest that infection with Epstein-Barr virus (EBV) can result in genetic alterations in B lymphocytes, potentially leading to the development of cancer cells and Hodgkin's lymphoma.The association with the Epstein–Barr virus (EBV) varies across the subtypesand is stronger in MCCHL and LDCHL and weaker in NSCHL and LRCHL. In making correct diagnoses and searches for possibilities of targeted therapy, the importance of the immunophenotype is difficult to overestimate. Current molecular research has shown the role of the PD-۱/PD-L۱, NF-κB and JAK/STAT pathways in the development of CHL. In classic subtypes of Hodgkin's lymphoma, malignant cells have a shared phenotype, and morphological characteristics contribute to the molecular diagnosis. This review aims to highlight the unusual diagnostic features of Hodgkin lymphoma as well as to explain some terms that can cause diagnostic ambiguity and should be viewed in relation to Hodgkin’s lymphoma.

کلیدواژه ها:

Hodgkin lymphoma ، molecular diagnosis ، classical Hodgkin lymphoma ، nodular lymphocyte predominant Hodgkin lymphoma