BACKGROUND: The progression of high-grade cervical intraepithelial neoplasia (CIN) and cervical cancer is accompanied by a reduction in the immune response. The objectives of the study were to determine whether colposcopic lesion area is associated with serum levels of cytokines IL (interleukin) -1, IL-6, IL-8, IL-10, IL-12 and TNF-α in precursor lesions of cervical cancer. METHODS: The study population comprised patients with high-grade squamous intraepithelial lesion who had undergone colposcopy, cervical biopsy, and measurements of serum cytokines by ELISA RESULTS: There were 71 patients with CIN 2/3. ROC curves were calculated to verify a cut-off value for serum cytokine levels that could be used to distinguish between lesion areas <
1 cm2 vs ≥1 cm2. Values with statistical significance were IL-1 >
13.3 pg/mL and IL-12 ≤349.6 pg/mL. In the multivariable analysis, the independent variables associated with colposcopic lesion area greater than 1cm CONCLUSION: Although CIN 2/3 is a local uterine cervix lesion, there is a systemic immunological response. Our results are unprecedented and could be the target of new important studies in public health and cervical cancer prevention.