TITLE:
HER-2/Neu Status in Gastric Carcinomas in a Series of Egyptian Patients and Its Relation to Ki-67 Expression
AUTHORS:
Saba El-Gendi, Iman Talaat, Mona Abdel-Hadi
KEYWORDS:
Egypt, FISH, Gastric Carcinoma, HER-2/Neu, Immunohistochemistry, Ki-67
JOURNAL NAME:
Open Journal of Pathology,
Vol.5 No.4,
August
17,
2015
ABSTRACT: Objective: HER-2/neu status in gastric
carcinomas (GCs) has not been studied before in the Egyptian population.
Materials and Methods: Seventy-three GCs were evaluated for the expression of
HER-2/neu and Ki-67 using immunohistochemistry (IHC). Fluorescence in situ
Hybridization (FISH) was done for HER2/neu IHC score 2+ cases. Results: Out of
the 73 gastric carcinomas, 23 (31.5%) were score 0, 17 (23.3%) were score 1+,
23 (31.5%) were score 2+, and 10 (13.7%) were score 3+. FISH analysis revealed
that the HER-2/neu gene was amplified in 11 out of the 23 cases (47.8%) scored
2+ by IHC. Therefore, the overall HER-2/neu positivity rate was 28.8% and it
was significantly associated with higher T-stage and lymphovascular invasion
(LVI). The Ki-67 expression rate ranged between 10% and 100%, with 84.9% of the
cases (n = 62) featuring high Ki-67 scores. High Ki-67 score was significantly
associated with male sex, tumor grade, and number of positive nodes. HER-2/neu
protein expression correlated significantly with Ki-67 score. Twenty tumors
showed combined HER-2/neu positivity and high Ki-67 score and were
significantly associated with higher T-stage and occurrence of LVI, implying a
more aggressive behavior. Conclusions: The rate of HER-2/neu positive GCs in
our series simulates universal rates, thereby mandating routine evaluation of
HER-2/neu status in all GCs submitted to our laboratory to benefit from
trastuzumab therapy. Further studies on a larger number of GCs are required to
prove that the concurrent HER-2/neu positivity and high Ki-67 score are markers
of worse prognosis.