If it's true that knowing history can unlock mysteries of the future, then new research from a group of University of Cambridge archeologists may be very telling.
In a first-of-its-kind study, the researchers analyzed 143 skeletons from six cemeteries in the Cambridge area in the United Kingdom from the 6th through the 16th centuries to estimate cancer incidence rates in medieval Britain. The researchers used visual inspection coupled with screening-using both plain radiographs and computed tomography scans-to detect malignant lesions.
The data revealed that, even though cancer rates at time of death in medieval Britain (9-14%) are estimated to be much lower than cancer rates at time of death now in modern times (40-50%), cancer incidence in medieval Britain may have been much higher than previously thought, the researcher concluded. The data was published in September in the journal Cancer (2021; https://doi.org/10.1002/cncr.33615).
"Our comparison of the medieval data with the prevalence of cancer during the 20th century indicates that cancer prevalence increased during the intervening period," the researchers noted in their paper. "This raises the question as to whether it will continue to increase in prevalence in the future. Only time will tell."
In an interview with Oncology Times, the study's lead author Piers Mitchell, MD, Director of the Ancient Parasites Laboratory in the Department of Archeology at University of Cambridge, shared details about the research, including why studying medieval cancer rates is important today.
1 Why is it important to study cancer rates in medieval populations and how is it even possible to do it?
"If we are to understand how trends in cancer prevalence may change over the next century, we need evidence for how prevalence has been changing over time. Then we can start to understand the degree to which particular triggers might be responsible for changing cancer risk.
"Understanding medieval cancer rates is important as they represent cancer risk prior to the introduction of smoking and those pollutants that became common during the Industrial Revolution in the 18th century.
"We studied the excavated human skeletal remains of people who lived in the medieval period to look for lesions of cancer metastases, and also screened their bones using X-rays and CT scans to look for metastases within the bones that could not be seen from the surface. We then went on to estimate the overall prevalence of cancer in the medieval population by factoring in information such as the proportion of people who die with cancer today who have metastases at the time of their death."
2 Were you surprised by what you found after completing this work?
"Before this study, estimates for the prevalence of cancer prior to the Industrial Revolution were based upon the visual appearance of metastases in excavated skeletons. This gave an estimated prevalence of around 1 percent.
"However, our screening the bones using X-rays and CT scans picked up extra cases in skeletons where the metastases were not visible on the surface. When we also factored in data for the proportion of people today with cancer who have metastases, we could then estimate that around 9-14 percent of adults in medieval Britain would have had cancer at the time of their death.
"It would be great to use our CT scan screening method to estimate the prevalence of cancers in other time periods (such as using Neolithic/Stone Age skeletons), and other regions of the world where a different set of infectious diseases would have been present."
3 What are the implications of your work for cancer researchers and cancer care providers today?
"We now know that cancer was much more common in the past than was previously thought. However, it was only about a third as common in medieval Britain as it is in modern Britain. The difference is likely to be due to the difference in life expectancy between medieval and modern people, the presence of modern industrial carcinogens, smoking, and infectious diseases (especially viruses) that trigger cancer.
"Contrary to what scientists used to think, cancer is not just a disease of modern civilization. Our ancestors have always suffered with it. It is gradually becoming more common over time, so targeting the factors that are causing this change can help us reduce cancer prevalence to lower levels. However, one of the key risk factors for cancer is our long life expectancy in modern societies, and we cannot do anything to mitigate that element of cancer risk."