FOLLICULAR LYMPHOMA.

Neoplastic cells closely resemble NORMAL GERMINAL CENTER B CELLS

Two principal cell types are observed in varying proportions

SMALL CLEAVED CELLS - centrocytes (Majority)

Larger cells called CENTROBLASTS

Nodular growth pattern is observed in involved lymph nodes

Involvement of extranodal sites is RARE

Transformation to diffuse large B cell lymphoma occurs in 30-50% cases

The follicles are numerous and irregularly sized.