The sections studied demonstrate mostly intact lymph node architecture with atypical expanded follicular structures on low magnification. The depicted follicles are disproportionately increased in size and have thickened mantle zones which frequently encroach into their germinal center and disrupting it.

Although not shown, examination at high magnification reveals an increased number of immunoblasts as characterized by slightly marginated chromatin and conspicuous centrally located nucleoli, present mostly in the perifollicular region. There are no definite large atypical cells ("L&H" or "popcorn" cells) present.

CD20 highlights the B-cells within the expanded follicular structures including the as well as mantle zone cells. Note the markedly enlarged PTGC follicle on top with reactive normal looking follicles at the bottom.

CD10 highlights germinal center B-cells only with a moth-eaten pattern of staining consistent with the encroachment of CD10-negative mantle zone cells within the follicles.

IgD and BCL2 highlight mantle zone cells and areas of progressive transformation of germinal centers with influx of mantle zone cells into the disrupted follicles. Compare to the reactive small secondary follicles at the bottom with positive staining for IgD and BCL2 restricted to mantle zone of secondary lymphoid follicle.

PD-1 and CD57 highlight increased numbers of T-follicular helper cells within the disrupted follicles.