TY - JOUR
T1 - Low histologic grade follicular lymphoma with high proliferation index
T2 - Morphologic and clinical features
AU - Wang, Sa A.
AU - Wang, Lan
AU - Hochberg, Ephraim P.
AU - Muzikansky, Alona
AU - Harris, Nancy Lee
AU - Hasserjian, Robert P.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2005/11
Y1 - 2005/11
N2 - Histologic grading has been used as a guide for clinical management in follicular lymphoma (FL). Proliferation index (PI) of FL generally correlates with tumor grade; however, in cases of discordance, it is not clear whether histologic grade or PI correlates with clinical aggressiveness. To objectively evaluate these cases, we determined PI by Ki-67 immunostaining in 142 cases of FL (48 grade 1, 71 grade 2, and 23 grade 3). A total of 24 cases FL with low histologic grade but high PI (LG-HPI) were identified, a frequency of 18%. On histologic examination, LG-HPIFL often exhibited blastoid features. Patients with LG-HPI FL had inferior disease-specific survival but a higher 5-year disease-free rate than low-grade FL with concordantly low PI (LG-LPI). However, transformation to diffuse large B-cell lymphoma was uncommon in LG-HPI cases (1 of 19; 5%) as compared with LG-LPI cases (27 of 74; 36%). In conclusion, LG-HPI FL appears to be a subgroup of FL with clinical behavior more akin to grade 3 FL. We propose that these LG-HPI FL cases should be classified separately from cases of low histologic grade FL with concordantly low PI.
AB - Histologic grading has been used as a guide for clinical management in follicular lymphoma (FL). Proliferation index (PI) of FL generally correlates with tumor grade; however, in cases of discordance, it is not clear whether histologic grade or PI correlates with clinical aggressiveness. To objectively evaluate these cases, we determined PI by Ki-67 immunostaining in 142 cases of FL (48 grade 1, 71 grade 2, and 23 grade 3). A total of 24 cases FL with low histologic grade but high PI (LG-HPI) were identified, a frequency of 18%. On histologic examination, LG-HPIFL often exhibited blastoid features. Patients with LG-HPI FL had inferior disease-specific survival but a higher 5-year disease-free rate than low-grade FL with concordantly low PI (LG-LPI). However, transformation to diffuse large B-cell lymphoma was uncommon in LG-HPI cases (1 of 19; 5%) as compared with LG-LPI cases (27 of 74; 36%). In conclusion, LG-HPI FL appears to be a subgroup of FL with clinical behavior more akin to grade 3 FL. We propose that these LG-HPI FL cases should be classified separately from cases of low histologic grade FL with concordantly low PI.
KW - Follicular lymphoma
KW - Grade
KW - Ki-67
KW - Proliferation index
KW - Survival
UR - http://www.scopus.com/inward/record.url?scp=27244440480&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=27244440480&partnerID=8YFLogxK
U2 - 10.1097/01.pas.0000172191.87176.3b
DO - 10.1097/01.pas.0000172191.87176.3b
M3 - Article
C2 - 16224216
AN - SCOPUS:27244440480
SN - 0147-5185
VL - 29
SP - 1490
EP - 1496
JO - American Journal of Surgical Pathology
JF - American Journal of Surgical Pathology
IS - 11
ER -