Dr. Mehreen Aftab, Ph.D
Urine self-sampling for HPV-based cervical cancer screening program in India.
Urine self-sampling for human papillomavirus (HPV)-based cervical cancer screening is a non-invasive method that offers several logistical advantages and high acceptability, reducing barriers related to low screening coverage. The development of a low-cost urine self-sampling method for HPV-testing and exploring the acceptability and feasibility of potential implementation of this alternative in routine screening remains an important and exciting challenge.
Urine is one of the interesting and useful biofluid for routine testing. Discovery of novel biomarkers can be done with the help of urine as it serves as an excellent resource for the same. It has an advantage over tissue biopsy samples due to the ease and non-invasive nature for collection of Urine. Noninvasive urine-based tests are particularly attractive for large-scale screening protocols, and biomarker discovery for detecting and predicting aggressiveness of cervical cancer.
A number of studies have analyzed the detection of HPV in urine and suggested that it can serve as noninvasive diagnostic and prognostic markers in cancer, and research in this area has increased. However, methodological and analytical difficulties exist and require addressing to enable future interpretation of the laboratory findings regarding HPV into clinical practice in cervical cancer.
Urine HPV-testing, employing this low-cost sampling procedure, offers good agreement with paired clinician-collected cervical samples. Furthermore, urine self-sampling seems to be highly acceptable and is an affordable method with good potential for implementation within the cervical cancer screening program in India.
HPV detection in urine samples has been reported with acceptable agreement compared to clinician-directed cervical samples in the study by Das et al. (1992). However, as previously documented by other studies, urine samples detected a larger proportion of HPV infections than cervical samples. This difference could be due to the fact that urine contains shed cells and mucus from many parts of the genito-urinary tract that contaminate the urine, whereas cervical samples are largely cervical cells. Urine self-samples could generate an increase in false positives, and therefore triage alternatives should be used to improve screening effectiveness.
HPV testing of urine appears feasible and reproducible but its analytic sensitivity comparisons with cervical HPV detection is less and it needs improvement. This could become a relevant method for providing screening to women in rural areas and to women who refuse the more invasive sampling required for cervical cytology testing. This would lead to an increase in coverage and timely treatment of high-grade lesions, potentially diminishing mortality rates and associated treatment costs of cervical cancer. Urine-self sampling is less expensive than cervical samples. Various studies support proposing urine as promising alternative for increasing coverage of cervical cancer screening programs worth further evaluation.
Urine contains cancer-derived subcellular components, such as DNAs, miRNAs, tumor cells, and exosome contain encapsulated DNA and miRNAs. These targets circulate throughout the patient’s body and have a number of clinical applications: cancer diagnose at early stages through detection and quantification of these targets; identify high-risk patients who necessitate intensive treatment; monitor drug efficacy to improve therapy for each patient; and monitor in real time the treatment’s effectiveness by correlating these targets with tumor size and stage. Urine or other liquid biopsy–based monitoring is potentially more sensitive at following treatment progress than imaging-based strategies or can be used together to improve the current monitoring protocols.
The study by Kate Simms et al. (2019) inspires hope for global elimination of cervical cancer, the burden of which is now largely in countries with low and middle Human Development Index (HDI). Given a future mathematical model to predict the elimination of global incidence and burden of cervical cancer will be possible by the end of this century, if two major primary prevention strategies 1) cervical screening and 2) HPV vaccination programmes are scaled-up to 80–100% coverage over the next 50 years. It is concerning that elimination at a national level might not include high-risk subgroups, such as indigenous women, who have higher cervical cancer incidence than their non-indigenous counterparts in countries with high-quality data.
Our main objective was to provide early evidence about whether urine sample using a new low-cost method could be successful in subsequent diagnostic trials.
Urine sampling strategy is worth further evaluation as it is also seen as feasible by healthcare professionals and accepted by patients for implementation as part of the cervical cancer screening program in India.
Further studies are however needed to address the procedural or methodological differences. Conceptual and methodological advances in the field will help to drive the development of novel urinary tests that in turn may lead to a shift in the clinical paradigm for early screening, diagnosis and management of cervical cancer.
So, there is a need to be given the call for global elimination of cervical cancer and widespread availability of Gene expert, optimizing expert HPV testing of urine may be warranted.
Author:
Dr. Mehreen Aftab, Ph.D
Ph.D. from Amity Institute of Molecular Medicine & Stem Cell Research (AIMMSCR), Amity University, Uttar Pradesh, India.
October 3, 2021
References:
1. Das BC, Krishna VG, Sharma JK, Roy M, Luthra UK. Human Papillomavirus DNA in urine of women with pre-neoplastic and neoplastic cervical lesions. The Lancet 1992; 340 1417-1418
2. Aftab, Mehreen et al. “Urine miRNA signature as a potential non-invasive diagnostic and prognostic biomarker in cervical cancer.” Scientific reports vol. 11,1 10323. 14 May. 2021, doi:10.1038/s41598-021-89388-w
3. Aftab, Mehreen, and B C Das. “Letter to the Editor/Comments on “First Void Urine: A potential biomarker source for triage of high risk human papillomavirus infected women” by Van Keer et al. Eur J Obstet Gynecol Reprod Biol 2017;Sep;216:1-11.” European journal of obstetrics, gynecology, and reproductive biology vol. 226 (2018): 71. doi:10.1016/j.ejogrb.2018.05.015
4. Hernández-López R, Hermosillo L, León-Maldonado L, Velázquez-Cruz R, Torres-Ibarra L, et al. “Performance of an affordable urine self-sampling method for human papillomavirus detection in Mexican women”. PLOS ONE vol. 16(2021):7:https://doi.org/10.1371/journal.pone.0254946