The section from a lymph node shows preserved architecture but the mantle zones are markedly thickened. The lymphocytes are monotonous in the mantle zone and are small to medium sized. There are reactive germinal centers present.

The cells in the mantle zone were positive for CD20, CD5, SOX 11 and Cyclin D1. Most mantle cell lymphomas are cyclinD1 positive but a percentage can be cyclinD1 negative as well. SOX-11 is a neural transcription factor, the nuclear expression of which is found in most mantle cell lymphomas. It can be a very helpful marker in identifying CyclinD1 positive and negative mantle cell lymphomas from other B-cell lymphomas. It is thought that Sox11 in MCL is expressed independently of cyclin D11 2. It is critical to take into account that though most nodal mantle cell lymphomas are SOX-11 positive and it can be a prognostic factor as well, there are SOX11-negativity mantle cell lymphomas. The SOX-11 negative MCL are mostly non-nodal and have an indolent clinical outcome3.

1.         Ek S, Dictor M, Jerkeman M, Jirström K, Borrebaeck CAK. Nuclear expression of the non–B-cell lineage Sox11 transcription factor identifies mantle cell lymphoma. Blood. 2008;111(2):800-805. doi:10.1182/blood-2007-06-093401

2.         Mozos A, Royo C, Hartmann E, et al. SOX11 expression is highly specific for mantle cell lymphoma and identifies the cyclin D1-negative subtype. Haematologica. 2009;94(11):1555-1562. doi:10.3324/haematol.2009.010264

3.         Ondrejka SL, Lai R, Smith SD, Hsi ED. Indolent mantle cell leukemia: a clinicopathological variant characterized by isolated lymphocytosis, interstitial bone marrow involvement, kappa light chain restriction, and good prognosis. Haematologica. 2011;96(8):1121-1127. doi:10.3324/haematol.2010.036277