[Roles of immunohistochemistry in prognostic assessment of basal-like breast cancer].
OBJECTIVE
Basal cell-like breast cancer is one of the subtypes using molecular typing, and this subtype attracted a wide spread attention. Currently, no uniform diagnostic criteria are available. Most studies demonstrated poor outcomes, but contradictory conclusions appeared recently. The prognosis of basal cell-like breast cancer using different immunohistochemical criteria were analyzed.


METHODS
Two hundred and eighty-four invasive breast cancers with a follow-up information over 5 years were evaluated for ER, PR, HER2, CK5/6, CK14, EGFR expression on tissue microarray immunohistochemically. Based on the results, these cases using four different diagnostic criteria were categorized, namely: Nielsen (ER-/HER2-, CK5/6+ and/or EGFR+), Kim (ER-/PR-/HER2-, CK5/6+ and/or CK14+ and/or EGFR+), Triple-negative (ER-/PR-/HER2-), and basal-CK (CK5/6+ and/or CK14+). 5-year survival information was compared between groups.


RESULTS
The prevalence of basal cell-like breast cancer by Nielsen, Kim, Triple-negative and basal-CK were 15.5% (44/284), 14.8% (42/284), 43.3% (123/284) and 21.1% (60/284) respectively; the recurrence rates were 18.2% (8/44), 21.4% (9/42), 10.6% (13/123) and 11.7% (7/60) respectively. These were higher than recurrence rates for other subtypes, but only the differences by Nielsen's and Kim's criteria were significant. Using Nielsen's and Triple-negative's criteria, basal-like tumors showed shorter 5-year disease-free survival (both P < 0. 01) and overall survival (P < 0.05 and 0.01) than luminal A subtype, using Kim's criteria, basal-like tumors showed a lower 5-year disease-free but not overall survival than luminal A subtype (P < 0.01); no significant difference was found on 5-year survival between basal-like and non-basal-like tumors when typed by basal-CK.


CONCLUSIONS
Basal cell-like breast cancers are more likely to show more recurrence and worse outcome, but different immunohistochemical diagnostic criteria have an influence on their prognostic analysis, so a uniform diagnostic criteria is essential for the further study of basal-like breast cancers.
Liu
Hui
H
Department of Pathology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China.
Fan
Qin-he
QH
Zhang
Zhi-hong
ZH
Li
Xiao
X
Yu
Hui-ping
HP
Liu
Guang-zhen
GZ
Meng
Fan-qing
FQ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000556:secondary; D001943:Breast Neoplasms / Q000145:classification / Q000378:metabolism / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism / Q000473:pathology* / Q000556:secondary; D018572:Disease-Free Survival; D066246:ErbB Receptors / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D053555:Keratin-5 / Q000378:metabolism; D053553:Keratin-6 / Q000378:metabolism; D008175:Lung Neoplasms / Q000556:secondary; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D018295:Neoplasms, Basal Cell / Q000378:metabolism / Q000473:pathology* / Q000556:secondary; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D015996:Survival Rate; D055815:Young Adult
D066246:ErbB Receptors; D053555:Keratin-5; D053553:Keratin-6; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human