The DCC protein and prognosis in colorectal cancer.

BACKGROUND  Allelic loss of chromosome 18q predicts a poor outcome in patients with stage II colorectal cancer.
Although the specific gene inactivated by this allelic loss has not been elucidated, the DCC (deleted in colorectal cancer) gene is a candidate.
We investigated whether the expression of the DCC protein in tumor cells is a prognostic marker in colorectal carcinoma.
METHODS  The expression of DCC was evaluated immunohistochemically in 132 paraffin-embedded samples from patients with curatively resected stage II and III colorectal carcinomas.
The Cox proportional-hazards model was used to adjust for covariates including age, sex, tumor site, degree of tumor differentiation, and use of adjuvant therapy.
RESULTS  The expression of DCC was a strong positive predictive factor for survival in both stage II and stage III colorectal carcinomas.
In patients with stage II disease whose tumors expressed DCC, the five-year survival rate was 94. 3 percent, whereas in patients with DCC-negative tumors, the survival rate was 61. 6 percent (P < 0. 001). In patients with stage III disease, the respective survival rates were 59. 3 percent and 33. 2 percent (P = 0. 03). CONCLUSIONS  DCC is a prognostic marker in patients with stage II or stage III colorectal cancer.
In stage II colorectal carcinomas, the absence of DCC identifies a subgroup of patients with lesions that behave like stage III cancers.
These findings may thus have therapeutic implications in this group of patients 
