Local health workers went house to house to recruit women and get family buy-in for this culturally delicate project. Participants were instructed to use their regular sanitary protection – most commonly a washable cloth – and told to call the health worker on the first day of menstruation. Health workers gave each woman a Ziploc bag for the pad and, for privacy, an outer polythene sac.
In Ahmednagar, all women who provided their pad also got screened with Hybrid Capture 2 (HC2; Qiagen) by a mobile screening unit. In Pune, only the positive cases underwent HC2. Screening was also extended to anyone who requested it, but these people were not included in the final analysis.
Genomic DNA was extracted from three 5 mm–sized punches in the pad using a commercial kit, QIAamp DNA Micro, and the quality and purity of the DNA checked by Implen NanoPhotometer.
The team followed the same protocol for PCR HPV assay as the team from Hong Kong.
The results were published in the European Journal of Cancer Prevention in 2018.
The concordance rate for a positive result between the menstrual pad sample and conventional HPV sampling was 98.8% for Ahmednagar and 95.2% for samples from Pune. The sensitivity for the first study was 83% and the specificity 99% – similar to that for the women in Hong Kong. The second study had lower sensitivity and specificity (67% and 88%), partly because of poor storage as a result of frequent power cuts.
The total cost per woman was $30.78.
“I was very excited when we saw the results,” Dr. Budukh recalled. “That day I couldn’t sleep ... such a wonderful result! I was excited to start the next phase immediately.”
Dr. Budukh has applied to the Indian government for funding for a larger trial involving 3,000 women. If successful, he hopes such evidence would be sufficient to convince the Indian government to make menstrual pad screening standard procedure for the 390 million women who live in India’s countryside.
Testing never-screened women for cervical cancer using menstrual pads appears to be relatively reliable, convenient, private, noninvasive, and incredibly cheap.
So who else has tried it?
The first published account of HPV in menstrual blood was a 2003 study by Tommy Tong and colleagues at the Princess Margaret Hospital in Hong Kong. The authors heralded, with lamentable optimism, “a new paradigm in cervical cancer screening.”
In the following 20 years, just six more studies appeared: two from Dr. Budukh’s field trial in India and four from hospital-based pilot studies in Hong Kong (in 2010 and 2018), South Korea (in 2016), and mainland China (in 2021). All these studies, although small, were published in top-flight journals and demonstrate high concordance between conventional high-risk HPV testing and menstrual-blood tests.
This news organization tried to find a U.S. thought-leader who had heard of the approach.
Elizabeth Fontham, MPH, DrPh, is the founding dean of the school of public health at Louisiana State University Health Center in New Orleans, and president of the American Cancer Society. Dr. Fontham said in an email that she had “no plans to evaluate the impact related to menstrual pads, but perhaps others have looked into that.”
Joy Melnikow, MD, MPH, was first author on the evidence synthesis driving the current cervical cancer screening recommendations from the U.S. Preventive Services Task Force. When asked about menstrual pad testing for HPV, she said she had “not heard of it before.”
The USPSTF guidelines don’t mention sanitary pads but acknowledge that “self-collection may be one strategy for increasing screening rates among populations where they are currently low.”
The USPSTF methodology excludes data from countries that don’t match the United States on the Human Development Index “or [are] not applicable to U.S. clinical settings or populations.” (Presumably, data from Hong Kong and South Korea would qualify; Indian data would not.)
Dr. Sahasrabuddhe of the NCI hadn’t heard of menstrual pad testing either, but he has a different explanation for lack of interest in this approach – or, indeed, any form of self-sampling for cervical cancer screening – in the United States.
“We have not seen movement happen in this space for years. ... If there is one intervention that we can simplify, that still has not been made widely available, it is self-sampling ... [but] we don’t have [Food and Drug Administration] approval for it,” Dr. Sahasrabuddhe said.
“Our system, at least in the U.S., is based on industry manufacturers seeking an approval for a particular way of collection and then clinicians and clinical-guideline bodies signing on. ... For a lot of reasons industry has shied away over the past several years, so far, at least, on seeking approval for self-sampling-based approaches,” he commented.
Dr. Sahasrabuddhe aims to change that. He heads a new NCI-led initiative called “The Last Mile,” a nationwide clinical trial supported by federal agencies, industry partners, and professional societies. The goal is to validate self-sampled HPV testing as non-inferior to specimens collected by providers. The team is currently finalizing the methodology of the study, so Dr. Sahasrabuddhe could not share the self-sampling methods that will be on trial, nor the industry partners who have signed up.
The following tests are approved in the United States for physician-collected HPV screening: Hybrid Capture 2, used in the Indian studies (Qiagen); cobas HPV (Roche); Aptima (Hologic); Cervista (Hologic); and Onclarity (Becton Dickinson).
Dr. Sahasrabuddhe said that, while a sanitary pad in a Ziploc bag is unlikely to make the grade for The Last Mile study, he doesn’t totally dismiss their potential and said the NCI is always open to new ideas.
“We are not supporting anybody specifically for menstrual pad-based collection device development,” Dr. Sahasrabuddhe said, “But if they fulfill other criteria for a small business–based grant application, they absolutely are welcome to apply for NCI funding for this.”
Said Dr. Melnikow: “Pre-COVID, the head of [the World Health Organization] said that we could eliminate cervical cancer from the globe and that we have the tools to do that now. And he’s right.”
Dr. Budukh, Dr. Melnikow, and Dr. Sahasrabuddhe disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.