The aberrant DNA methylation of tumour suppressor genes, including CADM1, MAL, and PAX1, is implicated in cervical carcinogenesis. Objectives: This pilot study aimed to evaluate the methylation levels of these genes in HPV-positive women and assess their diagnostic performance for detecting histologic high-grade squamous intraepithelial lesions (HSILs) and carcinoma. Methods: Cervical samples from 73 HPV-positive women were analyzed using droplet digital PCR (ddPCR) to quantify methylation levels of CADM1, MAL, and PAX1. The methylation levels were further compared across cytological and histological classifications. A control group of 26 HPV-negative women with negative cytology was also included. The diagnostic performance was assessed through receiver operating characteristic (ROC) analysis, as well as sensitivity and specificity calculations for individual genes and gene panels. Results: MAL methylation was absent in NILM, LSIL, and HSIL samples but was significantly elevated in carcinoma. PAX1 methylation was observed in both high-grade and some low-grade lesions. CADM1 methylation remained low or undetectable in the NILM, LSIL, and HSIL groups, with a significant increase observed in carcinoma cases. The CADM1/MAL panel demonstrated the highest diagnostic accuracy, with an area under the curve (AUC) of 0.912, 70% sensitivity, and 100% specificity. ddPCR exhibited superior analytical sensitivity compared to real-time PCR. Conclusions: The CADM1/MAL methylation panel, assessed by ddPCR, may serve as a specific biomarker for the triage of HPV-positive women at risk of HSIL and carcinoma. However, this study’s limited sample size and single-centre design necessitate cautious interpretation. Further validation in larger, population-based cohorts is necessary to confirm its clinical utility.

Aim. To assess the perinatal outcomes of monochorionic diamniotic (MCDA) pregnancy after fetoscopic laser coagulation of anastomoses (FLCA) performed for twin-to-twin transfusion syndrome (TTTS), accompanied by induced or unintentional septostomy, and to identify the factors leading to septostomy. Materials and methods. The retrospective study included 231 cases of FLCA performed in pregnant women with TTTS: in 19 cases septostomy was performed, and in 212 cases intertwin membrane remained intact. Results. The incidence of septostomy during FLCA for TTTS was 8.2%. In 47.3% the rupture of the intertwin membrane occurred during trocar insertion (unintentional septostomy); in 42.1% septostomy was needed to perform laser coagulation of anastomoses located on the placental surface in the donor's amnion (forced septostomy). The placenta was located on the anterior uterine wall in 78.9% in the septostomy group and in 47.6% with an intact intertwin membrane (p=0.01). Anastomoses were located on the donor half of the placenta significantly more often when septostomy was needed to perform selective coagulation of anastomoses located far from the intertwin membrane and obstructed by the body of the donor fetus (42.1%). In 15.8% of patients with septostomy and 2.4% with intact intertwin membrane, umbilical cords of the donor and the recipient fetus were attached closer than 2 cm to each other (p=0.003). In the septostomy group premature rupture of membranes was more frequent (42.1% vs 18.4%, p=0.03) and a delivery time was shorter [26.3 (18.0, 37.0) vs 34.4 (20.3, 40.0) weeks, respectively, p=0.01] than in patients with an intact intertwin membrane. The survival rate after FLCA was lower after septostomy compared to intact intertwin membrane: at least one of the twins survived in 47.4% vs 80.7%, respectively (p=0.002), both fetuses survived in 36.8% vs 75.0%, respectively (p=0.001). Logistic regression analysis showed increased risk of septostomy in patients with the anastomoses located on the donor half of the placenta and when the donor and the recipient umbilical cords are attached close to each other, regardless of the localization of the placenta, gestational age and the stage of TTTS. Conclusion. Lower incidence of unintentional septostomy during FLCA achieved by using modern equipment and surgical techniques will lead to better perinatal outcomes in patients with MCDA twins with TTTS.