lundi, septembre 07, 2009

toxic exposures and the secret history of the war on cancer

***Update: My test results came back negative. The good scientists at John's Hopkins are 97% certain that I do not have genetic abnormalities consistent with VHL.

Six years ago last Friday, surgeons carved my right kidney out of my body, removing malignant cells that, left untreated, would have led to certain death. The tumors that my doctors later biopsied indicated that I had the most common form of kidney cancer - clear cell. My medical record was updated to read "T1N0M0".

After absorbing the shock of my diagnosis and proceeding to my straightforward and relatively easy treatment (I say that because I have many friends who endured much worse in their battles with cancer), I was left with two key questions:
  1. Why did this happen?
  2. And how do I keep it from happening again?
To answer these questions, I had to learn a great deal more about my cancer. The American Cancer Society's Cancer Facts & Figures 2009 will tell you that kidney cancer is the seventh most common cancer in the US; the five-year survival rate is about 67%. It will also provide trend data for who the "typical" kidney cancer patient is.

The American Society for Clinical Oncology explains how cells mutate and the role that genes play:
Genes control how a cell functions, including how quickly it grows, how often it divides, and how long it lives. To control these functions, genes produce proteins that perform specific tasks and act as messengers for the cell. Therefore, it is essential that each gene have the correct instructions or "code" for making its protein so that the protein can perform the proper function for the cell.

Cancer begins when one or more genes in a cell are mutated (changed), creating an abnormal protein or no protein at all. The information provided by an abnormal protein is different from that of a normal protein, which can cause cells to multiply uncontrollably and become cancerous.

A person may either be born with a genetic mutation in all of their cells (germline mutation) or acquire a genetic mutation in a single cell during his or her lifetime. An acquired mutation is passed on to all cells that develop from that single cell (called a somatic mutation). Most kidney cancers (about 95%) are considered sporadic, meaning that the damage to the genes occurs by chance after a person is born. Inherited kidney cancers are less common (about 5%) and occur when gene mutations are passed within a family, from one generation to the next.
The Massachusetts Department of Public Health has correlated environmental factors (smoking, obesity, and occupational hazards such as asbestos, cadmium, organic solvents, and petroleum) with kidney cancer, yet stops short of proclaiming causality. (Agent Orange is another suspect substance.) You'll notice that although researchers can characterize the abnormal growth and correlate the incidence of cancer with genetics and some substances, they can't tell us with certainty what causes it. Part of that is because more research needs to occur, but can't because industry and government make it difficult for that research to take place (see the article below).

Barbara Ehrenrich's amazing essay, Welcome to Cancerland, forever changed how I think about the role of the environment in my health. It also set me down a path to try and answer the Why and How questions I grappled with immediately after diagnosis. But like most cancer patients, I'll probably never know exactly what caused my body to turn on itself when I was 28. However, unlike most cancer patients, I've gotten a step closer to knowing if my genes are the reason for my illness.

A few months ago, I saw a genetic counselor. I chose to do so because Leo and I hope to start a family soon. I wanted to know the risk factors for certain hereditary conditions. Most of all, I wanted to know if my cancer was something that I could pass on to our children. Over the years, I've casually researched the topic and given up the hope of ever finding out if there was a genetic basis for my cancer, in short because every time I broached the topic with medical professionals, they would immediately tell me that I'd already had kidney cancer, so they already knew I was at a higher risk for having it. With this context, you can only imagine how dumbfounded I was when, after asking me a series of questions, the genetic counselor asked if I had heard of Von Hippel-Lindau Syndrome (VHL) and suggested that I be tested for it.

Last week, the counselor called me back to let me know that my HMO had agreed for me to be tested for VHL because it is the most common cause of clear cell kidney cancer (and a host of other life-threatening issues). Setting aside the interesting Hatfield-McCoy connection, it's some seriously scary stuff. If I do have it, those same skeptical medical professionals will now need to routinely screen me for a whole host of other medical issues that have nothing to do with my cancer history. Also, if I do have the VHL genetic mutation, there's a 50% chance that I'll pass it along to my children.

Setting VHL aside, I'm still unsure if the mutation that caused my cancer (whether it occurred in me or started in my parents or grandparents) happened because of something I ate, drank, breathed, or absorbed. All of this puts me back at square one in this maddening, dizzying recursive loop of what triggered the chain of events that led to my current health.

So ... I'm back to casually researching the connections between cancer and our environment and disgusted to see how, for the past century, our government and industry have failed to act on existing knowledge about the environmental causes of cancer. Read on to learn more about the ugly toxic exposures and the secret history of the war on cancer ...
Theories of cancer: How paradigms shift and culprits change in the fight against the disease, and what concerned citizens can do about it
Sandra Steingraber -- From The Times Literary Supplement
January 30, 2008

Devra Davis
SECRET HISTORY OF THE WAR ON CANCER
505pp. Basic Books. £16.99.
978 0 465 01566 5

Phil Brown
TOXIC EXPOSURES
Contested illnesses and the environmental health movement
356pp. New York: Columbia University Press. £19 (US $29.50).
978 0 231 12948 0

One advantage of being a long-time cancer survivor – besides the obvious – is that it provides a front-row seat in the auditorium of ideas about the disease’s causation. Theories go in and out of fashion over the years, paradigms shift this way and that, and the patient is viewed differently by the medical community depending on which idea is currently on top.

I was diagnosed with bladder cancer in 1979, when I was twenty years old and just at the beginning of my career as a biologist. At that time, US newspaper headlines featured Love Canal, the upstate New York community whose residents had been evacuated a year earlier when 20,000 tons of industrial chemicals were discovered buried under their basements. Toxic-waste activism in the United States was in the ascendant, the newly formed US Environmental Protection Agency was committed and passionate, and major environmental legislation had been recently enacted by Congress to defend clean air and clean water in the name of human health.

After breaking the bad news from the pathology lab, my urologist asked me about tyres: automobile tyres. Had I ever vulcanized tyres? His second question was about textile dyes. Any exposure to the colour yellow? And had I ever worked in the aluminium industry?

Back at the university, I began to research the causes of bladder cancer. Indeed, there were data on dyes and bladder cancer going back to the nineteenth century. In fact, there was absolute proof that certain textile dyes caused bladder cancer in humans. And yet, mysteriously, this evidence had not resulted in the abolition of these chemicals from the economy. Other suspected bladder carcinogens, for which the evidence was highly troubling, if not outright damning, were produced and used by the industries in my home town. The National Cancer Institute was generating maps of cancer mortality in an attempt to unveil other possible environmental carcinogens that could explain rising rates of cancer.

And then Ronald Reagan was elected President, and everything changed. No one asked me any more about my possible environmental exposures. In fact, by the mid-1980s, I was hard-pressed to find the word “carcinogen” in any pamphlet on cancer that I collected from my doctors’ various offices. Meanwhile, in the medical literature, the search for cancer clusters that might point towards environmental contributors became a disparaged practice. The new focus of the National Cancer Institute was on “lifestyle” explanations for cancer.

As a young adult I hadn’t really had enough time to develop bad habits. In fact, I was a vegetarian who ran four miles a day. Thus there was no explanation for my situation. “Some kind of fluke”, said one of my doctors. Wherever I lived, I dutifully submitted to cancer check-ups. By the 1990s, the new explanation for cancer was genetic, and I started receiving lots of questions from young intake doctors about my family history. I had fun with this. I would describe in detail my mother, diagnosed with breast cancer, my various uncles with prostate and colon cancers, and – the crowning point – my aunt who died of the same kind of bladder cancer that I had. The young doctors took furious notes. I would always pause a few beats before adding, “Oh yeah. And I’m adopted”. (There is no evidence for a hereditary link to bladder cancer. And there never has been.)

Today, I’m a forty-eight-year-old professor in Ithaca, New York, and during my last renal ultrasound, the technician asked me casually if I’d ever worked with textile dyes. I suppose Al Gore should get the credit: the environment is once again on the collective radar screen.

Two new books expose and explicate the ongoing social contest that is at the heart of our shifting understanding about cancer. They are both important and deserve to be read together. Devra Davis’s book examines the historical forces at work when doubt is cast on the environmental evidence. Phil Brown’s book explores the opposing social movements that are struggling to rescue this evidence and to bring about public health policy change based on it.

Devra Davis’s Secret History of the War on Cancer is a big, sprawling book whose argument is more implicit than it should be. Her autobiographical style – which served her so well in her earlier treatise on public health, When Smoke Ran Like Water – often gets in the way of her analysis here. Nevertheless, Davis, who directs the Center for Environmental Oncology at the University of Pittsburgh Cancer Institute, is an epidemiologist and public-health scientist at the top of her game. In her new book, she reveals what she knows about the interlocking structures of government and corporate interests, and how these relationships have affected the social construction of knowledge about cancer. Davis deserves to be taken seriously as a former adviser to the World Health Organization, a public-health servant in both the Carter and the Clinton Administrations, and the founding director of the Board on Environmental Studies and Toxicology in the National Academy of Sciences.

The basic thesis of this book is that 1.5 million lives have been lost, because Americans failed to act on existing knowledge about the environmental causes of cancer. This failure has been created by at least eight different factors, both acting together and independently of each other. The first is the cowardice of research scientists, who publish thoroughly referenced reports but pull their punches at the end, by claiming that more research needs to be done before action can be taken. Statements like these are then exploited by those who profit from the status quo. Like the cigarette industry during the 1960s, the chemical industry has learned how to buy time and create wholesale public doubt from small data gaps and remaining scientific uncertainties.

Meanwhile, Davis argues, regulatory agencies have become unresponsive to new scientific evidence altogether. Hamstrung by small-government-is-better reforms of the Reagan Administration, environmental and public agencies shrank even as the science began pointing to the need for more regulation. As for the government agencies and charities whose mission it is to eradicate cancer, these institutions, too, have had meaningful work on cancer prevention compromised by corporate interests. Throughout the 1980s, for example, the chief executive officer of Occidental Petroleum served as the chair of the National Cancer Institute’s advisory board. Ultimately, the so-called War on Cancer is not really a war at all, argues Davis, but a cunning re-enactment.

The evolutionary history of epidemiology itself has also played a role in muffling the evidence for environmental harm. With its necessary focus on workers – who are exposed to the highest amounts of suspected carcinogens – epidemiologists require access to industry. The price for access, too often, is the promise of secrecy. Having struck a Faustian bargain, occupational epidemiologists can have – and have had – their funds withdrawn if they go public with their results.

A further factor involves the court system. Davis shows brilliantly the ways in which various kinds of scientific evidence – such as animal research – have been gradually declared inadmissible in legal cases, thanks to clever lawyering. “Basically”, says Davis, “before you can collect damages, you must get cancer or some other awful disease, show that someone else already got it from the same things you did, prove that you had specific exposures to a particular agent, find the firm that caused your harm and can now pay for it, and prove that they knew the exposure was harmful.”

The last two factors involve outright harassment of researchers, including Davis herself, and plain old terrible timing, which has occurred at least twice in the last century, as when major treatises on the environmental contributors to cancer were released, first on the brink of the First World War, and then again right before the Second World War. Indeed, Davis’s crowning achievement with this book is her resuscitation of old publications, along with secret memos and various other original manuscripts, which show how much we used to know about the role that chemical exposures play in the burden of cancer. Some of these were subsequently doctored to serve particular purposes.

The Secret History of the War on Cancer is a remarkable piece of sleuthing from one of our most brave and knowledgeable scientists, on a topic that affects millions. Having closed Davis’s book, one should immediately open Phil Brown’s Toxic Exposures, which focuses on the ways in which environmental- health activists and their advocates in science are challenging the carcinogen-deniers that Davis writes about. Like Devra Davis, Brown, a medical sociologist at Brown University, has been a researcher in the field of environmental health for several decades, beginning with his groundbreaking work on the Woburn cancer cluster, made famous in the Hollywood movie A Civil Action. His new book represents many years of work. Toxic Exposures can be read as a guidebook for those wishing to understand the environmental-health movement, which, according to Brown, is the Civil Rights movement of our times. As he demonstrates, almost all cases of cancer clusters and contaminated communities, from Love Canal onwards, have been discovered by citizen activists – not by scientists, nor government agencies. This is because no governmental agency or scientific body engages in routine surveillance that would uncover sentinel health events. It is also because cancer registries, which could function as early-warning systems, publish their results in obscure almanacs and do not actively investigate communities where cancer rates are elevated. Often, as Brown notes, these communities are never even informed that their cancer rates are statistically excessive.

But, in the cases where citizens have engaged in their own lay epidemiology and have become environmental detectives in their own communities, new avenues of scientific research have been made possible, which, in turn, have spurred on better environmental decisions. When sympathetic scientists work hand in hand with these activists, new forms of knowledge are created that challenge the lifestyle and hereditary foci of conventional epidemiology.

In one my favourite examples from the book, Brown describes how science alone failed to produce regulations sufficient to reduce lead poisoning among children. It was only the efforts of black and Latino rights groups – most notably the Black Panthers and the Young Lords – in the 1960s that finally led to the social changes necessary to get lead away from children’s brains. Once that happened, science had the human experiment it needed to prove that exposures to an environmental toxicant at levels once considered acceptable and unavoidable were not safe or necessary after all.

Brown’s book systematically examines citizen-science alliances in three disease areas: breast cancer, asthma and Gulf War Syndrome as reported by US veterans of the first Iraq war. While individual readers who are not sociologists will no doubt be drawn, by personal experience, to one of the three, all offer important lessons about the construction of scientific knowledge. It was fascinating to learn, for example, how environmental -justice activists working on asthma clusters in urban areas are now forcing scientists to investigate the health effects of very fine particles, which are not yet regulated by the Environmental Protection Agency.

In the end, Phil Brown’s analysis of contested illnesses makes a strong case for better health tracking to monitor diseases, and better chemicals tracking to monitor the flow of hazardous substances in consumer goods, in the jet stream, in our groundwater, and in our tuna-fish sandwiches. Toxic Exposures also makes clear that neither will happen without citizen participation in the scientific process.

Sandra Steingraber is the author of Living Downstream: An ecologist looks at cancer and the environment, 1997, and Having Faith: An ecologist's journey to motherhood, 2001.

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