Myelomonocytic/monocytic lineage involvement is also a characteristic of polysomy
Determining true HER2 gene status in breast cancers with polysomy
by using alternative chromosome 17 reference genes: implications for anti-HER2 targeted therapy.
Since the current clinical guidelines for amplification and polysomy
are defined by the cut-off values for MP data, the AD cannot be readily used for decision support without proper validation.
Determination of HER-2 status and chromosome 17 polysomy
in breast carcinomas comparing HercepTest and PathVysion FISH assay.
Two of these had polysomy
17 and thus a false positivity by IHC18; whereas, the reasons for the other case could be due to one of the following reasons, viz.
and supernumerary isochromosomes in the grasshopper Omocestus bolivari (Chopard).
Chromosome 17 polysomy
: a unifying hypothesis underlying benefit from adjuvant anthracyclines?
Within this group, the new investigation determined that 25 patients (19%) had polysomy
(defined as 2.2 copies or more per cell) of chromosome 17.
(25-31) Given the evidence that some group 3 cases have true HER2 amplification rather than polysomy
for chromosome 17, particularly when the HER2 copy number is high, the Expert Panel ultimately favored continuing to classify these cases as HER2 positive unless the concurrent IHC result is clearly negative (0 or 1+).
For EGFR, samples were grouped as normal disomy, [less than or equal to] 2 centromere signals in [greater than or equal to] 40% of cells; low polysomy/trisomy, [greater than or equal to] 3 centromere signals in [greater than or equal to] 40% of cells, excluding cases with high polysomy
or gene amplification; high polysomy
, [greater than or equal to] 4 centromere signals in [greater than or equal to] 40% of cells, excluding cases with gene amplification; and gene amplification, ratio of gene/chromosome [greater than or equal to] 2 or clusters of probes (>10 copies per tumour cell) in [greater than or equal to] 40% of cells.
A lung adenocarcinoma without ROS1 fusion showing (C) patchy ROSI IHC staining and (D) FISH exhibiting polysomy
but no evidence of rearrangement (original magnifications X200 [A and C] and X630 [B and D]).
HER2/neu overexpression has been linked with polysomy
of chromosome 17.