Gain of chromosome 8q23-24 is a predictive marker for lymph node positivity in colorectal cancer.
OBJECTIVE
The prognosis of patients with colorectal cancer is largely determined by tumor stage. In this respect, colorectal cancers with lymph node metastases indicate a worse prognosis versus lymph node-negative tumors. Accordingly, there is considerable clinical interest in understanding the genetic mechanisms underlying metastasis formation. Furthermore, sensitive and specific biomarkers are needed to predict the metastatic phenotype at the time of diagnosis.


METHODS
Fifty colorectal cancers with or without lymph node metastases were assessed for genomic imbalances by comparative genomic hybridization. Particular interest was focused on whether specific chromosomal alterations exist in primary tumors that might be indicative and specific for the metastatic phenotype.


RESULTS
The analysis revealed that lymph node-positive colorectal cancers show a higher degree of chromosomal instability than lymph node-negative cancers (average number of chromosomal copy alterations, 9.8 versus 7.5). Chromosomal alterations commonly described in colorectal cancers such as gain of 20q or loss of 18q21 were not different. However, the gain of chromosomal region 8q23-24 was seen in the vast majority of lymph node-positive cancers, whereas it was rather rare in lymph node-negative carcinomas (P = 0.0016).


CONCLUSIONS
These data suggest that genes located at 8q23-24 might favor the development of lymphatic metastases in colorectal cancers. Additionally, the gain of this region could be used to predict the metastatic potential of primary colorectal cancers.
Department of General, Visceral, and Transplantation Surgery, University Medical Center Göttingen, Germany. mghadimi@surgery-goettingen.de
B Michael
BM
Ghadimi
Marian
M
Grade
Torsten
T
Liersch
Claus
C
Langer
Alexander
A
Siemer
László
L
Füzesi
Heinz
H
Becker
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis; D002898:Chromosomes, Human, Pair 8 / Q000235:genetics*; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000556:secondary*; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D042822:Genomic Instability; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009693:Nucleic Acid Hybridization / Q000379:methods; D011237:Predictive Value of Tests; D011379:Prognosis
D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm