Effectiveness of cryotherapy delivered by nurses for treatment of cervical preneoplasic lesions

Introduction. Cervical cancer is a relevant public health problem for low- and middleincome countries. Follow-up of positive-screened women and compliance with treatment of precancerous lesions are major challenges for these settings. Objective. To evaluate the efficacy of cryotherapy delivered by nurses for cervical intraepithelial neoplasia (CIN). Materials and methods. Direct visual inspection with acetic acid and lugol iodine (VIAVILI), and colposcopy/biopsy were performed on women 25 to 59 years old, residents of low-income areas in Bogotá, Colombia. Trained nurses offered immediate cryotherapy to every woman with positive visual inspection. Colposcopy/biopsy was performed before treatment and at a 12-month follow-up. The effectiveness was measured as cure (outcome: no-lesion) and regression (outcome: CIN1) rates of CIN2/3 using colposcopic and histological verification. Results. A group of 4.957 women with VIA/VILI was valuated. In total, 499 were screen positive and 472 accepted immediate treatment. A total of 365 women (11 CIN2/3) received cryotherapy by nurses. Cure rate was 72% (95%CI: 39%-94%) and 40% (95%CI: 22%-85%) by colposcopic and histological verification, respectively. Regression rates were 100% and 60%. There were two related non-serious adverse events. Conclusions. Cure and regression rates by colposcopic verification are like those reported for cryotherapy delivered by doctors. The sample size (CIN2/3) hinders comparisons by type of verification. Our findings support the implementation of screen-and-treat algorithms by nurses among populations with limited access to health services.