Low grade follicular lymphoma with high proliferation index; diagnostic and management issues

Follicular Lymphoma (FL) is the second most common B-Non Hodgkin Lymphoma after diffuse large B cell lymphoma (DLBCL). Low grade FL is known for its indolent behavior; however, one subset of FL behave aggressively and may require intensive therapy. One of the diagnostic issues in FL is to identify this subgroup of cases. Proliferation index can have prognostic importance in this subset of cases. We discuss one case of low grade FL with a paradoxically high proliferative index. A 63 year male presented with generalized lymphadenopathy of one year duration, which was gradually increasing in size. On examination, patient had bilateral cervical, axillary and inguinal nodes. Biopsy of the left cervical lymph node was reported as FL-Grade 2, with high proliferative Index (60%). The patient was put on CHOP regimen targeted for high grade lymphomas, and had complete remission. High proliferative index in FL is a poor prognostic factor irrespective of the histologic grade. So, proliferative index should be assessed in all cases of FL as an adjunct to histologic grading.