Abnormal lymph node mantle zone morphology Lymph node with expanded mantle zones 2023-11-10T19:15:33Z Enlargement of the typical outer ring of small lymphocytes (mantle zone) surrounding a germinal center of a lymph node. Secondary follicles (follicles with germinal centers) typically show mantle zones which are a rim or band of mostly B cells surrounding germinal centers that on H&E appears as densely packed small lymphocytes immediately surrounding germinal centers. The mantle zone is usually relatively thin (i.e. only a few rows of lymphocytes extending out from the germinal center), however may be significantly expanded, particularly in mantle cell lymphoma. Germinal centres with expanded mantle zones Germinal centers with expanded mantle zones