Reagents and Conditions Used for Immunohistochemistry.

<p>Reagents and Conditions Used for Immunohistochemistry.</p

Summary of Immunohistologic Findings.

<p>Summary of Immunohistologic Findings.</p

Morphology of isolated atypical follicles.

<p>An axillary lymph node dissection in a 61 year-old woman with breast carcinoma (case 1) shows one lymph node with scattered follicles containing sheets of centroblasts (A). The involved follicles exhibit sheets of large atypical cells with highly pleomorphic nuclear outlines and atypical mitoses (B). An axillary lymph node from a 53-year old woman (case 2) shows highly atypical large cells occupying an involved follicle (C). Sections of tonsil in a 6-year old boy (case 5) demonstrate a background of reactive follicular hyperplasia within which isolated follicles (upper left) show sheets of centroblasts (E and F).</p

Atypical expression of HGAL in isolated atypical follicles.

<p>An axillary lymph node in a 53-year old woman (case 2) shows a single atypical follicle with pleomorphic large cells overexpressing HGAL (A and B). Sections of the tonsil in a 6-year old boy stained with HGAL, show preservation of overall architecture with numerous normal reactive follicles and a gradient of HGAL staining with higher intensity in the dark zone. In the atypical follicle (indicated by arrow in panel D), HGAL staining is abnormal and shows overexpression throughout the affected follicle (C and D).</p