In order to correctly diagnose HL, a biopsy of the affected lymph node must be taken and then analyzed by a pathologist. After the biopsy, you may feel soreness and there may be some bruising.

Once a histologic diagnosis has been reached, additional tests will be done to complete your medical history, such as a physical examination, blood test, and a test of liver and kidney function. A CT scan and PET scan will be conducted to determine what areas of the disease is in, and a biopsy will follow.

Stages of HL

Once a histologic study and the above-mentioned additional tests are done, your medical team will set out to classify the disease based on its location and where it is spreading to. Classification helps in planning and deciding on the most appropriate treatment.

• Stage I: The lymphoma is affecting only one area of the lymphatic system or just one lymphoid structure such as the spleen or thymus.
• Stage II: The lymphoma has affected two or more areas of the lymphatic system located on the same side of the diaphragm.
• Stage III: Areas located on both sides of the diaphragm have been affected.
• Stage IV: Several non-lymphatic organs have been affected, or multifocal involvement of one non-lymphatic organ or of the bone marrow.

After the lymphoma has been classified, secondary information is added:

A: no associated symptoms

B: fever ≥38 degrees Celsius, night sweating, unexplained loss of more than 10% of bodyweight over the last few months

X: Tumors are referred to as "bulky tumors" when they are at least one-third as wide as the mediastinum or tumor masses measuring over 10 cm in diameter.

E: Only one extranodal site located beside or next to a nodal site is affected.