TISSUES: Lymph node
GROSS DESCRIPTION: Specimen submitted in formalin labeled core biopsy of abdominal mass consists of 5 cylindrical cores of pale tan tissue ranging from 1.7 to 3 cm in length and 0.1 cm diameter.
MICROSCOPIC DESCRIPTION: Sections show about a half-dozen needle biopsy fragments with a nodular and diffuse infiltrate of mostly small, cleaved centrocytes within a sclerotic background.
Special Stains Performed:
BCL-6 Positive Strong nuclear staining in areas with follicular architecture with only dim-equivocal staining in the more diffuse areas.
CD20 Positive
CyclinD1 Negative
Ki67MIB1 See comment Low proliferation fraction: <5% in most areas, but up to 20-30% focally.
FINAL DIAGNOSIS:
Follicular lymphoma, grade 1-2.