9698/3 Malignant lymphoma, large cell, noncleaved, follicular



Definitions

Tumours of haematopoietic and lymphoid tissues
ICD-O-3 topography code: C42 and C77
ICD10: C82.2 grade 3; C82.3 grade 3a; C82.4 grade 3b
           

A follicular lymphoma grade 3 contains more than 15 centroblasts per 40X high-power microscopic field.

This grade is further subdivided into:

> Follicular lymphoma (FL) grade 3a, which contains centrocytes, admixed with centroblasts numbering >15/hpf and
ICD-10 C82.3

> Follicular lymphoma grade 3b, which contains only centroblasts, without identifiable centrocytes.
CD-10 C82.4

Grade 3b FL is often associated with Diffuse large B-cell lymphoma (DLBCL), NOS, and in this setting both diagnoses should be reported. At the biological level FL Grade 3b is closely related to DLBCL, and typically is negative for translocations involving BCL2. Complete long term remissions are more common in FL Grade 3b than in FL Grade 3a.