Bruno de Oliveira Fonseca

Multiscale Optical Imaging Fusion for Cervical Precancer Diagnosis: Integrating Widefield Colposcopy and High-Resolution Endomicroscopy

Early detection and treatment of cervical precancers can prevent disease progression. However, in low-resource communities with a high incidence of cervical cancer, high equipment costs and a shortage of specialists hinder preventative strategies. This manuscript presents a low-cost multiscale in vivo optical imaging system coupled with a computer-aided diagnostic system that could enable accurate, real-time diagnosis of high-grade cervical precancers. The system combines portable colposcopy and high-resolution endomicroscopy (HRME) to acquire spatially registered widefield and microscopy videos. A multiscale imaging fusion network (MSFN) was developed to identify cervical intraepithelial neoplasia grade 2 or more severe (CIN 2+). The MSFN automatically identifies and segments the ectocervix and lesions from colposcopy images, extracts nuclear morphology features from HRME videos, and integrates the colposcopy and HRME information. With a threshold value set to achieve sensitivity equal to clinical impression (0.98 [p = 1.0]), the MSFN achieved a significantly higher specificity than clinical impression (0.75 vs. 0.43, p = 0.000006). Our findings show that multiscale optical imaging of the cervix allows the highly sensitive and specific detection of high-grade precancers. The multiscale imaging system and MSFN could facilitate the accurate, real-time diagnosis of cervical precancers in low-resource settings.

Evaluation of human papillomavirus self-collection offered by community health workers at home visits among under-screened women in Brazil

Objective To explore the acceptability of high-risk human papillomavirus self-testing, involving community health workers, for never/under-screened Brazilian women. Cervical cancer is the most common cause of cancer-related death among adult women in a large number of low-income and lower-middle-income countries, where it remains a major public health problem. High-risk human papillomavirus persistence is required for the development of cervical neoplasia. Methods The target population was all women aged 30+ from the list of families available in healthcare centre data, who had never been screened or were not screened in the previous 3 years (under-screened women), and who were living in the 17 cities included in this study. Results Of the 377 women included, 16.9% ( n = 64) had never had a pap smear. Of all samples included in the study, 97.1% ( n = 366) were considered adequate for evaluation, as 2.9% ( n = 11) were considered invalid for all high-risk human papillomavirus types. Analysing these 366 samples, 9.6% ( n = 35) of the women were infected by at least one high-risk human papillomavirus type and 90.4% ( n = 331) had no infection with any high-risk type of the virus. Conclusions Vaginal self-sampling is an adequate strategy to improve the effectiveness of the cervical cancer program by increasing screening in a high-risk group.