Newly diagnosed and relapsed follicular lymphoma: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up.

Diagnosis should always be based on a surgical specimen/ excisional lymph node biopsy. Core biopsies should only be performed in patients without easily acessable lymph nodes (e.g. retroperitoneal bulk). Fineneedle aspiration is inappropriate for a reliable diagnosis. The histological report should give the diagnosis according to the WHO classification. Grading is performed according to the number of blast per high-power field (grade 1–2: £15 blasts, grade 3: >15 blasts). Follicular lymphoma grade 3B (with sheets of blasts) is considered an aggressive lymphoma and treated alike (see Clinical Practice Guidelines for diffuse large B-cell lymphoma). When possible additional biopsy material should be stored fresh frozen to allow additional molecular (currently still scientific) analyses. staging and risk assessment