In relatively poor countries where a lack of infrastructure prevents widespread implementation of effective screening programs, collecting a small sample of cells only from women at high risk of cervical cancer could be a cost-effective approach for early diagnosis.
Cervical cancer is now the second leading type of cancer among women in developing countries. Every year, about 250,000 women die of the disease, most of them from low- and middle-income countries.
The problem is that wealthier countries generally offer nationwide cervical screening to all women. Doctors collect only a small sample of cells (cytology) to diagnose pre-cancerous lesions before they progress to cancer. In less developed nations, poor infrastructures and management make such programs difficult, meaning more women are diagnosed in later stages of the disease.
But researchers at QMUL have now found that cytology could still improve rates of early cervical cancer diagnosis, if given only to women experiencing symptoms of cervical lesions, and referring only those with substantial lesions for follow-up. Their study, which was funded by Cancer Research UK, recently appeared in the Journal of Global Oncology.
“Cytology has long been established as an excellent screening tool to prevent cervical cancer by detecting pre-cancerous lesions, QMUL’s Alejandra Castanon, MD, said in a news release. “However, little research has been carried out regarding its sensitivity to cancer.”
The team investigated cytology results from 717 cervical cancers. They analyzed 23 studies conducted in low- and middle-income countries including Argentina, Bangladesh, Brazil, China, Costa Rica, Egypt, El Salvador, India, Kenya, Peru, South Africa, Thailand and Uganda. Even in countries with fewer resources, they concluded, cytology was very sensitive and consistent for detecting invasive cervical cancer. In high-risk women showing symptoms, the method was 95.9 percent accurate.
“We’ve found that this is an excellent tool for targeted screening of populations at high risk of cervical cancer, leading to early diagnosis,” Castanon said. “In resource-poor settings with limited facilities to treat advanced cancers, this could have a big impact on cervical cancer mortality.”
Performing a cytology only in high-risk women with symptoms and referring only those with severe lesions for further investigation could, therefore, reduce the costs of cervical cancer screening and still result in early cervical cancer diagnosis.
“The implications are that, even when a country lacks infrastructure to implement a quality-assured cervical screening program nationally, it might be able to facilitate early diagnosis of cervical cancer by using cervical cytology, and only referring women with severely abnormal smears,” said Peter Sasieni, who co-authored the study.