Telomerase activity is a prognostic factor for recurrence and survival in rectal cancer.

PURPOSE

This study was designed to determine whether telomerase activity measured in samples of tumoral tissue, transitional mucosa, and normal mucosa from patients with sporadic colorectal cancer is a prognostic factor for recurrence and overall survival.

METHODS

Telomerase activity was determined by fluorescence-based telomeric repeat amplification in tissue samples from 108 patients with sporadic colorectal cancer. A telomerase index was determined by using the formula log (telomerase activity of cancer tissue - telomerase activity of normal mucosa).

RESULTS

Mean telomerase activity in tumoral tissue was 11.49 (total product generated), in transitional mucosa it was 1.51, and in normal mucosa it was 1.09 (P < 0.001). Telomerase activity and telomerase index were not correlated with clinicopathologic factors. Rectal cancer patients' recurrence-free survival was related to N classification (P = 0.004) and to tumor-node-metastases stage classification (P = 0.023) and telomerase index 0.85 (P = 0.023). Overall survival was associated with N classification (positive/negative) and telomerase index (</=0.85 or >0.85; P = 0.018 and P = 0.011, respectively).

CONCLUSIONS

Measurement of telomerase activity has a diagnostic value in colorectal patients. In rectal cancer, telomerase index is an independent prognostic factor for disease progression. A telomerase index</=0.85 and negative nodes can be used to predict disease progression.