DNA ploidy status and prognosis in colorectal cancer: a meta-analysis of published data.
OBJECTIVE
In colorectal cancer, the negative effect of aneuploidy has been a controversy for more than 20 years. Studies to determine a survival-deoxyribonucleic acid content relationship have conflicting results. A systematic literature search followed by a meta-analysis of published studies addressing prognostic effect of aneuploidy for patients who underwent surgical treatment of colon and rectal cancer was conducted.


METHODS
The main outcome measure was the five-year overall mortality rate after surgical resection. For the selected studies, we estimated this outcome for three subsets of patients through separate meta-analyses: 1) for all patients with colorectal cancer; 2) only between patients with Stage II colon cancer; and 3) only for studies in which follow-up losses were declared. The presence of publication bias was assessed with a funnel plot for asymmetry.


RESULTS
A total of 5,478 patients with colorectal cancer were represented in 32 studies (Group 1), we estimated a reduction in the five-year overall mortality from 43.2 percent for aneuploid tumors to 29.2 percent for diploid tumors (combined relative risk = 1.44; 95 percent confidence interval = 1.34-1.55; P < 0.001). In addition, 357 patients with Stage II colon cancer (Group 2) extracted from three studies had an absolute reduction of 14.3 percent in five-year overall mortality favoring diploid tumors (combined relative risk = 1.93; 95 percent confidence interval = 1.29-2.89; P = 0.001). Lastly, of 14 studies in which follow-up losses were declared (Group 3), 2,221 patients were represented and a 15.7 percent mortality reduction was measured favoring patients with diploid tumors (combined relative risk = 1.44; 95 percent confidence interval = 1.3-1.61; P < 0.001).


CONCLUSIONS
Patients who undergo an aneuploid colorectal cancer surgical resection have a higher risk of death after five years. This finding may ultimately impact survival of patients with node-negative colon cancer through adjuvant therapy.
Araujo
Sergio E A
SE
Department of Gastroenterology, Surgical Division, University of Sao Paulo Medical School, Cristiano Viana 450, ap 62, 05411 - 000, Sao Paulo, Brazil. sergioed@terra.com.br
Bernardo
Wanderley M
WM
Habr-Gama
Angelita
A
Kiss
Desiderio R
DR
Cecconello
Ivan
I
D000782:Aneuploidy; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000401:mortality*; D004273:DNA, Neoplasm / Q000235:genetics*; D006801:Humans; D011379:Prognosis; D017594:Publication Bias; D016019:Survival Analysis
D004273:DNA, Neoplasm