Grading follicular lymphoma on fine needle aspiration specimens. Comparison with proliferative index by DNA image analysis and Ki-67 labeling index.
OBJECTIVE
To determine whether follicular lymphoma (FL) can be graded on fine needle aspiration (FNA) biopsies by determining the percentage of centroblasts in the neoplastic follicles on the smears.


METHODS
Eighty-nine cases of histologically confirmed cases of FL, including 31 grade 1, 46 grade 2 and 12 grade 3, were evaluated. Proliferative index (PI) by DNA image analysis (DIA) and Ki-67 labeling index (LI) were obtained on all cases. A minimum of 200 cells were counted per case (range, 200-800 cells) at 40x magnification, and the number of large cells (centroblasts) was expressed as a percentage of the total number of cells counted within the follicles.


RESULTS
The percentage of centroblasts in the follicular aggregates was 9.7 +/- 2.9% in grade 1 FLs, 24.7 +/- 5.6% in grade 2 and 48.4 +/- 7.5% in grade 3. These differences were significant (P < .05). DNA image analysis of PI and Ki-67 LI differed significantly between grade 1 FLs and grade 2 and 3 FLs (P < .05), but there were no significant differences between grade 2 and 3 FLs.


CONCLUSIONS
Determining the percentage of centroblasts in the follicular aggregates on FNA specimens is a good method of grading FLs. Using the percentage of centroblasts per follicular structure, FL grades 1, 2 and 3 were adequately distinguished. PI by DIA and Ki-67 LI clearly distinguished FL grade 1 from FL grades 2 and 3; however, it did not clearly distinguish between grades 2 and 3.
Sun
Wei
W
Division of Pathology and Laboratory Medicine, Department of Pathology, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 053, Houston, Texas 77030, USA.
Caraway
Nancy P
NP
Zhang
Hua-Zhong
HZ
Khanna
Abha
A
Payne
Linda G
LG
Katz
Ruth L
RL
D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle / Q000379:methods* / Q000592:standards / Q000639:trends; D002452:Cell Count / Q000592:standards; D002455:Cell Division / Q000235:genetics; D002467:Cell Nucleus / Q000473:pathology; D003584:Cytological Techniques / Q000379:methods* / Q000592:standards / Q000639:trends; D004247:DNA / Q000032:analysis; D005260:Female; D006801:Humans; D019044:Image Cytometry; D007150:Immunohistochemistry / Q000592:standards; D019394:Ki-67 Antigen / Q000032:analysis / Q000096:biosynthesis*; D008213:Lymphocyte Activation / Q000235:genetics; D008224:Lymphoma, Follicular / Q000145:classification / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D008940:Mitotic Index; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D014626:Vaginal Smears / Q000592:standards
D019394:Ki-67 Antigen; D004247:DNA