Significance of Unamplified Chromosome 17 Monosomy in Breast Carcinoma
U Krishnamurti, FD Atem, JF Silverman. Western Pennsylvania Hospital, Pittsburgh, PA; Allegheny General Hospital, Pittsburgh, PA; University of Pittsburgh, Pittsburgh, PA
Background: HER2 gene amplification is a poor prognostic indicator in breast carcinoma. Some patients show chromosome 17 aneusomy with or without HER2 amplification. We have in an earlier study demonstrated the poor prognostic effect of unamplified polysomy 17 in breast carcinoma (Mod Pathol 22:1044; 2009). The aim of this study was to determine the effect of unamplified 17 monosomy on prognostic factors in invasive breast carcinoma.
Design: Monosomy 17 was defined as the presence of less than 1.5 chromosome 17 centromere copies/cell. Four groups: N (no polysomy or HER2 amplification, 36 cases), M (unamplified 17 monosomy, 23 cases), P (unamplified 17 polysomy, 44 cases) and A (HER2 amplification without 17 polysomy, 35 cases) were compared for the following: Nottingham score, nuclear grade, mitotic score, histologic grade, lymphvascular invasion, nodal metastases, T stage, estrogen receptor (ER) and progesterone receptor (PR) negativity. SAS 9.2 was used for statistical analysis.
Results: The percentage of prognostic factors is the different groups is given in the table.
|Prognostic factors||% N||% M||% P||% A||N vs. M||N vs. P||N vs. A|
|Nottingham score 8||11||27||37||34||-||-||-|
|Nottingham score 9||11||11||14||34||-||-||p=0.05|
|Nuclear grade 3||26||44||61||74||p=0.001||-||p=0.012|
|Mitotic score 2||18||33||54||43||-||-||-|
|Mitotic score 3||18||11||26||40||-||-||p=0.04|
|Histoogic grade 3||20||37||44||69||-||-||p=0.03|
|T stage 2||18||11||31||30||-||p=0.03||p=0.03|
|Lymph vascular invasion present||17||38||19||34||-||-||-|
|Positive lymph nodes||38||40||42||45||-||-||-|