Lymphoma: Clinical

Lymphoma is a malignancy of lymphocytes - that is B-cells, T-cells, and natural killer cells - that usually involves the lymph nodes, or other lymphoid structures like the tonsils and the spleen.

Lymphoma is considered the most common hematologic malignancy in adults.

If there’s an enlarged lymph node, so lymphadenopathy, it’s important to see if it’s tender and if it’s mobile.

In reactive lymphadenopathy due to an infection, the lymph node is typically tender and mobile.

If the lymph node is due to lymphoma or from a metastasis from another malignancy, the lymph node is typically non-tender and non-mobile or fixed.

In malignancy, lymphadenopathy can also be accompanied by “B” symptoms, which are caused by cytokine release, and include a fever, drenching sweats, and an unintentional 10% weight loss within six months.

If malignancy is suspected, an excisional lymph node biopsy should be done to assess the tissue architecture of the lymph node, because the hallmark of lymphoma is a disruption of this lymph node architecture. This is done by completely removing the entire lymph node surgically.

A fine needle aspiration, or FNA of the lymph node is inadequate for making the diagnosis, because an FNA is just poking a needle into the lymph node, and aspirating or pulling out lymphocytes. And any individual lymphocyte in lymphoma could look completely normal.

If the excisional biopsy confirms that there’s a lymphoma it’s generally classified as a Hodgkin lymphoma or non-Hodgkin lymphoma based on the presence or absence of Reed-Sternberg cells.

Reed-Sternberg cells have a bilobed nucleus and a surrounding clear space!

Once the diagnosis of Hodgkin lymphoma or non-Hodgkin lymphoma is made, the next step is to do staging using positron emission tomography combined with a computed tomography, or PET/CT scan of the chest, abdomen, and pelvis. This is done by giving the patient an intravenous bolus of radiolabeled glucose, called fluorodeoxyglucose, or FDG.