Expression of iNOS--a favourable prognostic marker for early-stage carcinoma of the uterine cervix.

In former studies, raised urine cGMP levels have been reported to predict adverse outcome in cervical cancer. The main objective of the present study was to investigate the value of nitric oxide synthase (iNOS) and other members of the cGMP pathway as potential biomarkers for prognosis of cervical carcinoma. Tissue samples from 85 patients surgically treated for early-stage cervical carcinoma were immunohistochemically stained for iNOS, soluble guanylyl cyclase subunits α1 (sGC-α1), soluble guanylyl cyclase α2 (sGC-α2), and phosphodiesterase 5, each sample evaluated microscopically by a semi-quantitative score. Results were correlated to recurrence and FIGO stage (depth of tumour cell infiltration). Correlation was found between high expression of iNOS in tumour cells and low risk of recurrence (p=0.019, p=0.05, p=0.022 and p=0.025). High expression of iNOS, sGC-α1 and sGC-α2 also correlated to superficial tumour growth. Our results demonstrate that iNOS expression in cervical tumour tissue is a robust prognostic marker for cervical cancer.