Follicular Lymphoma : Grade 1
Follicular lymphomas are subdivided into 3 grades in the WHO classification based on the relative proportion of centrocytes and centroblasts. The prognosis worsens with increasing number of centroblasts. Centroblasts are counted in 10 to 20 high power fields (40x) in randomly selected follicles. Grade 1: zero to 5 centroblasts/hpf; Grade 2: 6-15 centroblasts/hpf; Grade 3: >15 centroblasts/hpf. This case showed only rare (<5) centroblasts/hpf and would be classified as Grade 1. These patients are usually asymptomatic and present with generalized lymphadenopathy, often with extranodal involvement (liver & bone marrow). The prognosis is good and aggressive treatment is not warranted.