Cancer: lessons to learn from the past

Introduction

Today cancer-related deaths approach nearly 10 million people worldwide, predilecting for a growth in low- and middle-income countries, with death rates influenced by aging and lifestyle factors risks [ ]. Although cancer-related mortality is ubiquitous, human populations experience the burden of oncological disorders differently. Dissimilarities in hereditary, environmental, and sociocultural factors explain the disparity in mortality experienced in diverse regions of the world [ ]. Relationships between these variables in elevating or decreasing cancer risk are complex and yet to be entirely understood and would benefit from a long-term, diachronic perspective.

Today's perspective on cancers will therefore be usefully informed by knowledge of cancers in the past, a field of study presenting a number of challenges. In the following essay, we discuss the current state of knowledge of the study of these ancient cancers, focusing on the long-term trajectory of malignant neoplasms based on the most direct sources of its evidence, the human skeletal remains and mummified bodies. We begin by identifying the scientists who study ancient cancers, followed by discussing the manner in which such cancers are studied and the current state of our knowledge including theoretical debates. A closing statement is made on the theoretical advances and the probable course that future studies will take.

Who studies cancer(s) in ancient people(s)?

Anthropological specialists who focus upon cancers in the past are most commonly identified as either paleo-oncologists, paleopathologists, or bioarchaeologists, depending upon their training and their focus. Historians of disease also contribute to this field, but since our focus here extends beyond the written record, we will emphasize the anthropological disciplines.

The field of paleo-oncology, a term first coined by physicians at the 13th International Congress of Chemotherapy in Vienna in 1983 [ ], has the potential to illustrate how oncological diseases impacted past societies. Paleo-oncology seeks to answer diverse and pressing questions, regarding the history and development of neoplasms, such as: Do we encounter evidence of malignant and benign neoplasms in the past? How far back in time does the first evidence of cancer appear within our species? Did cancer reach a global scale before recent times? Is cancer a phenomenon of modern societies and extremely rare in antiquity? Are the biological, pathological, or genetic expressions of malignant neoplasm different from what is known clinically today? How was the evolution and natural history of cancer modulated by variability in sociocultural practices, diet, lifestyle, ecological, and environmental shifts in past societies [ ]?

Paleo-oncology is a subfield within the discipline of paleopathology, defined as the study of diseases in past populations based on a retrospective pathological diagnosis, i.e., the recognition of pathological changes on human remains (skeletons, mummified bodies, and other biological elements), complemented with a plethora of secondary sources (historical, iconographic, or documentary) [ ]. Since “disease is always generated, experienced, defined, and ameliorated within a [bio]social world” [ ] (p.2333), scholars engaged in the research of past communities' health and the history of disease must necessary do so under a biocultural lens, i.e., with the integration of archaeological, ecological, historical, sociocultural, ethnographic, demographic, and biological parameters [ , , ]. As such, paleopathology is exceptionally positioned to unveil the history and biology of diseases, the longitudinal and evolutionary impact of diseases in our species, and the dynamics between humans and the ecological and sociocultural spheres [ ]. On a smaller scale, paleopathology also provides stimulating insights on which kind of diseases affected a group of people in a particular temporal and spatial frame, or even how an individual's impairment carried a meaning within their social life experiences (e.g., stigma and disability) [ , ].

At a broader level, paleopathology is also a key contributor to the field of bioarchaeology, i.e., the study of human remains retrieved from archaeological sites, that precisely integrates a biocultural approach while reconstructing past peoples' lived experiences [ , , ]. Bioarchaeology is wide in scope, embracing not only human health but topics such as “human growth, demography, human ecology, sociopolitical and subsistence transitions, epigenetics and developmental biology, and social theoretical approaches to understanding the conceptualization of mortuary landscapes, spatial organization of cemeteries, embodiment of social identity, and more” [ ] (p.4).