Conclusions
These results suggest that RNR subunit expression may discriminate cervical cancer phenotype and radiochemotherapy outcome. Future RNR biomarker studies are warranted.
Objective
To evaluate pretherapy ribonucleotide reductase (RNR) expression and its effect on radiochemotherapeutic outcome in women with cervical cancer.
Results
Fifty-one tissue samples were analyzed: 13 from RTOG 0116 and 38 from RTOG 0128. M1, M2, and M2b overexpression (3+) frequencies were 2%, 80%, and 47%, respectively. Low-level (0-1+, n = 44/51) expression of the regulatory subunit M1 did not associate with DFS (P = 0.38). High (3+) M2 expression occurred in most (n = 41/51) but without impact alone on DFS (hazard ratio, 0.54; 95% confidence interval, 0.2-1.4; P = 0.20). After adjusting for M2b status, pelvic node-positive women had increased hazard for relapse or death (hazard ratio, 5.5; 95% confidence interval, 2.2-13.8; P = 0.0003). Conclusions: These results suggest that RNR subunit expression may discriminate cervical cancer phenotype and radiochemotherapy outcome. Future RNR biomarker studies are warranted.