Hippocrates gave cancer its name. He used the words "carcinos" and "carcinoma" to describe tumours – Greek words for crab.
At the time, 400 B.C., cancer was discovered in the end stage, when tumours were a hard mass, like a crab's shell. The sharp pain of end-stage cancer that patients described also reminded Hippocrates of the pinch of a crab's claw.
Hippocrates, the father of Western medicine, also thought cancer was caused by black bile (one of the four bodily fluids believed responsible for all illness), a theory that was accepted into the 17th century, when scientists began to understand the circulatory and lymphatic systems.
It wasn't until the late 19th century that Rudolph Virchow recognized that cancerous cells divide uncontrollably and invade other tissues by spreading through the blood and lymph system.
We know now that cancer is not one disease but many diseases that have their origins in a complex mix of genetics, lifestyle factors and triggers (ranging from smoking to poverty). Still, the No. 1 risk factor remains aging, which is why cancer kills more people today than it ever has, with public health measures such as sanitation having dramatically reduced infectious disease deaths.
There are hundreds of different types of cancer, most of which are named for the organ or type of cell in which they start.
We also know that not all tumours are cancerous – they can be malignant (spreading to other parts of the body) or benign (they do not spread). Some cancers, like leukemia, do not even form tumours at all.
Further, thanks to technological advances, we can now detect tumours at a microscopic level and abnormalities right down to a cellular level – and we can do so in living people. (For the longest time, cancer was studied only in corpses, reinforcing the notion of deadliness.) The paradox is that we can now detect a lot of cancer that is, well, not even cancer yet and likely never will be.
An estimated 75,000 Canadians will die of cancer this year. Approximately 177,800 new cases of cancer will be diagnosed in Canada this year.
For every one of those people, the cancer diagnosis will pack a punch. When you hear the words "you have cancer," the assumption is that you're going to suffer and you're going to die prematurely.
For many, many "cancers," that simply isn't true any more.
So, should we be telling folks with abnormalities or weird-looking cells that they have cancer?
This is a question that health professionals, activists and patients themselves are increasingly struggling with.
Essentially, we need a new cancer lexicon – one in which the language reflects the knowledge of the 21st century, not the fears of 400 B.C.
The Canadian Cancer Society, in its annual tally of cancer diagnoses, excludes the 74,100 non-melanoma skin cancers because they are localized abnormalities.
Given evolving scientific knowledge, it may well be time to start making that distinction for some forms of breast, prostate and thyroid "cancers."
In a recent column, Gina Kolata of The New York Times made the point eloquently with the example of ductal carcinoma in situ (DCIS), also known as stage 0 breast cancer.
DCIS is an accumulation of abnormal-looking cells in the milk ducts of the breast. This condition was unknown before mammography screening because there is no lump that can be felt, but the "weird cells" show up on X-rays.
DCIS now accounts for one in five cases of breast cancer. But is it actually cancer at all? It is true that DCIS is not always benign; it can spread from the milk ducts to elsewhere, but there is no good evidence showing that treating it before it spreads is beneficial.
A panel of experts from the U.S. National Institutes of Health concluded that DCIS is not a carcinoma, so it should be renamed "high-grade dysplasia."
That distinction already exists in the cervical cancer field, where cervical carcinoma in situ(in the body) was renamed cervical intraepithelial neoplasia. Women understand too that an abnormal Pap test does not automatically mean they have cancer; they make the distinction between dysplasia and cancer.
The fastest-growing cancer in Canada is thyroid cancer. But, again, that is misleading. As with DCIS, we now have technology that can detect nodules on the thyroid. But the vast majority are benign – they will have no negative health consequence, unless you start cutting them out.
Is that really cancer?
Language matters because it influences behaviour.
When you use the dreaded C-word the reaction of patients is to want to rid their body of a deadly passenger: They want to cut it out – whether it's in a breast, a prostate or a thyroid.
But cutting and burning and poisoning – surgery, radiation and chemotherapy if you prefer the more technical terms – are not always the best response to weird-looking cells.
Watchful waiting is becoming an increasingly common practice, particularly with prostate cancer, where the screening test (PSA or prostate specific antigen) is notoriously poor and tumour growth often very slow.
The severity of prostate cancer is determined using something called Gleason scoring. The physician who created this system, Donald Gleason, has suggested that the most common tumours (Gleason 3 + 3) actually be renamed adenosis, a term used to describe benign swelling.
Prostate cancer is sometimes described as a cancer you die with, not a cancer you die of. We are learning that this is true of many other "cancers." Increasingly, we have the ability to make those distinctions, and we should do so.
We do ourselves a disservice when conditions as wildly different as a grade 4 glioblastoma multiforme (a brain tumour that is virtually 100-per-cent fatal) and prostatic intraepithelial neoplasia (a condition more likely to make you pee often than kill you) are both described as cancer.
Hippocrates is best known not for his naming of cancer but his admonition to physicians to, above all, do no harm.
Right now, our crude, imprecise use of the term cancer is doing harm. The words we use need to reflect our knowledge, and influence practice.