Lymphoma should not be dichotomised into Hodgkin and non-Hodgkin lymphomas as it’s “no longer conceptually useful, makes little biologic sense and results in a loss of valuable information,”  a group of international clinicians say.

According to haematologist Professor Robert Gale, from the Imperial College London, UK, and colleagues, Hodgkin lymphoma is a sub-type of non-Hodgkin lymphoma and the use of an “exclusionary designator” for a disease “lacks precision and courts confusion”.

“Our proposal is not to abolish the designator Hodgkin lymphoma as a specific lymphoma sub-type but rather the clinical and biologically irrational dichotomisation of lymphomas into Hodgkin and non-Hodgkin lymphomas,” they wrote in a perspective piece published in the British Journal of Haematology,

They noted that 190 years had passed since Sir Thomas Hodgkin first described features of massive lymph node enlargement and other severe symptoms within the autopsy reports of seven patients, which was subsequently named as Hodgkin’s disease by Samuel Wilks in 1865.

Since it was named Hodgkin disease, lymphomas have been classified as Hodgkin and non-Hodgkin lymphomas, but according to the haematologists, it was not known why, as “the clinical features of Hodgkin’s cases were not unique and most were later determined to not have Hodgkin lymphoma”.

Also, we now know that “lymphomas are cancers of B- and T- lymphocytes and that Hodgkin lymphoma arises in a B-lymphocyte like other B-lymphocyte lymphomas such as diffuse large B-cell lymphoma (DLBCL), follicular lymphoma, mantle cell lymphoma (MCL), small cell lymphoma (SCL) and others,” they explained.

And given the significant advance in understanding of the condition since its nomenclature was first established, “it has become clear the distinction between Hodgkin lymphoma and other lymphomas prolongs an artificial clinical and biologic dichotomy” they noted.

They also claimed that the argument for treatment as a justification for the dichotomisation of lymphoma doesn’t hold up. “Can it be reasonably argued that therapy of Hodgkin lymphoma with regimens such as ABVD and BEACOPP justifies distinguishing it from all other lymphomas? We think not,” they wrote.

“For example, the combination of bendamustine and rituximab is widely used to treat mantle cell lymphoma but would be inappropriate as initial therapy for DLBCL. CHOP-R has remained the therapy choice for most DLBCLs, but EPOCH-R is favoured for high-grade B-cell double-hit lymphomas. CHOP-R would be inappropriate for Burkitt lymphoma and classical Hodgkin lymphoma.”

As such, they suggest that lymphomas are no longer be dichotomised into Hodgkin and non-Hodgkin lymphomas, and that “the effect is to make Hodgkin lymphoma, seemingly paradoxically, into a non-Hodgkin lymphoma”.