Low power image demonstrates broad bands of compartmentalizing sclerosis noted as the pink areas with nodular structures containing an atypical lymphoid infiltrate.

High power at the periphery of the nodule demonstrates prominent sclerosis with mottled appearance to the nodules due to scattered large atypical cells with somewhat clear cytoplasm present in a background of small lymphocytes.

At higher power, there are scattered large cells with clear cytoplasm and central nuclei present in a background of small lymphocytes. Further examination demonstrates that the large cells are either mononuclear or multinucleated variants of Hodgkin/Reed-Sternberg cells, also called "lacunar cells". Lacunar cells represent an artifact of formalin fixation due to retraction of the cell membrane as a result of formalin fixation.

This image demonstrates two dark mummified cells which are Hodgkin cells that have undergone nuclear condensation.

CD20 immunostain (bottom left) demonstrates scattered small B cells staining positive for CD20 while the Hodgkin cells are negative for CD20, consistent with down regulation of germinal center and B-cell program in the cells.

Likewise, PAX5 (bottom right) demonstrates strong nuclear positivity in the surrounding B cells while the clusters of the Hodgkin cells in the center of the field demonstrate weak PAX5 expression consistent with the down-regulation of germinal center and B-cell program in these cells.

All classical Hodgkin lymphoma cells express uniform CD30 with prominent Golgi accentuation in many cells. Staining is typically cytoplasmic as well as membranous. Targeted therapy again CD30 (brentuximab) is available currently in the relapsed setting for cHL.

CD15 on the other hand, is positive in the Hodgkin cells and expression is often weak and focal with somewhat granular staining. Normally, numerous background neutrophils in the strong CD15 while background monocytes express moderate CD15 and serve as internal controls.