Wednesday, May 1, 2013

The downsides of overdiagnosing


The New York Times recently published two thought-provoking pieces on the downsides of overtesting and overdiagnosing women: in the Sunday magazine, a cover story about breast cancer "overawareness" by Peggy Orenstein; and on Monday, a post on the Well blog about the value of pelvic exams by Jane E. Brody.
Both pieces raise questions about procedures that have become all too familiar to North American women: the mammogram and bimanual exam (if you don't know what a bimanual exam is, Brody describes it thusly: "The doctor inserts a lubricated, gloved finger into her vagina and, with the other hand, presses down on her abdomen to check the shape and size of her uterus and ovaries.")
These procedures save lives -- or so women have been told over and over again. But Orenstein and Brody ask: do they really? And at what cost?
Orenstein's story is interesting because she is a breast cancer survivor herself and once wrote a piece in the New York Times crediting the mammogram with saving her life.
She now regrets writing this article, as she tells the Times' 6th Floor blog, having learned more about the science of breast cancer and how awareness campaigns have overemphasized the mammogram's value without also acknowledging the risks.
Orenstein writes:
"For an individual woman in her 50s, then, annual mammograms may catch breast cancer, but they reduce the risk of dying of the disease over the next 10 years by only .07 percentage points — from .53 percent to .46 percent. Reductions for women in their 40s are even smaller, from .35 percent to .3 percent.
If screening’s benefits have been overstated, its potential harms are little discussed. According to a survey of randomized clinical trials involving 600,000 women around the world, for every 2,000 women screened annually over 10 years, one life is prolonged but 10 healthy women are given diagnoses of breast cancer and unnecessarily treated, often with therapies that themselves have life-threatening side effects."
Yet, women have been bombarded with messaging about the importance of mammograms and regular self-exams, often by breast cancer awareness campaigns that have deluged the world with pink ribbons. As one surgical oncologist said to Orenstein: "There is so much ‘awareness’ about breast cancer in the U.S. I’ve called it breast-cancer overawareness. It’s everywhere. There are pink garbage trucks. Women are petrified.” 
With Brody's piece, she points out the paucity of scientific evidence supporting annual bimanual exams for healthy women -- something even the American College of Obstetricians and Gynecologists acknowledges. Nonetheless, 63.4 million pelvic exams are performed in the United States every year and the routine performance of this invasive procedure "increases costs of medical care and discourages some women, especially adolescents, from seeking needed care."
Moreover, Brody writes, "the exam sometimes reveals benign conditions that lead to follow-up procedures, including surgery, that do not improve a woman’s health but instead cause anxiety, lost time from work, potential complications and unnecessary costs."
One journal article mentioned in Brody's post suggests that routine bimanual exams in the U.S. could partly explain why rates of ovarian cystectomies and hysterectomies are more than double the rates in European countries, where only symptomatic women are given pelvic exams.
In another study she cites, researchers found that ovarian cancers were not detected by pelvic examination alone and is not in itself an effective screening tool -- yet, almost 70 per cent of ob/gyns believed it was.
"Whenever doctors are doing things by rote, we have to rethink whether what they're doing is really helpful," Dr. George F. Sawaya told Brody in an interview.
Jennifer Yang is the Star’s global health reporter. She previously worked as a general assignment reporter and won a NNA in 2011 for her explanatory piece on the Chilean mining disaster. Follow her on Twitter: @jyangstar

No comments:

Post a Comment