Paleopathology: do ancient cancers hold lessons for modern cancers?
September 29, 2010 § Leave a comment
Jagesh Shah sent me this intriguing recent review, which gives an overview of the results in a field I never knew existed: paleopathology. [I guess I kind of did know the field existed, from debates about whether Lincoln had Marfan syndrome and questions about whether “the royal disease” was hemophilia. Still, I didn’t know how far back it goes.] It seems that now and then, archeologists find an Egyptian mummy that has clear evidence of a tumor, or even a dinosaur skeleton; these are most often found in bone, not soft tissue, for obvious reasons, but there are occasional soft tissue findings as well. The question then is whether, although the findings are sparse, we can learn something about the prevalence and nature of cancer in ancient human and animal populations.
The only ancient society where a significant sample of preserved human remains is available is Egypt. But for other ancient societies, we can look at the medical texts. These make grim reading, but they give an indication of which cancers early physicians tended to see. Breast “eating” and “eating of the uterus” are prominent, and they were treated with red-hot irons, magic spells, fumigation and excision. The Romans recognized that none of their treatments seemed to work, and that excision sometimes made things worse. Mastectomy was also tried; Rhazes, an Arab physician from the 9th century AD, is on record as warning that inadequate excision may be worse than no treatment at all.
The (fragmentary) evidence both from medical texts and from examination of remains seems to support the idea that cancers were rarer than they are today. Is that because we live longer, or because we expose ourselves to more environmental toxins? The authors appear to take the view that the answer is probably a bit of both. They chronicle fascinating but probably rare cancer types such as scrotal cancer in chimney sweeps (why, I wonder?), and nasal cancer in snuff users (now, that one’s obvious). But since even wealthy Egyptians had an average life expectancy of only 40-50 years, the lack of time for cancer to develop must also have been a factor.
Possibly the coolest part of this review is that one of the authors is employed by a Center for Biomedical Egyptology. Their web page features Anubis (god of physicians and embalmers) bending over a sarcophagus. There’s so little romance in science these days — but even if paleopathology ends up being all about genome sequencing of ancient tumors, the fact that Anubis is involved will add a certain frisson. At least for me.
David AR, Zimmerman MR. (2010). Cancer: an old disease, a new disease or something in between? Nat Rev Cancer., 10 (10), 728-733 : 20814420