Tuesday, September 03, 2013

Indolentomas: What is and is not cancer?

Check out this recent article and accompanying video by George Lundberg on Medscape entitled, "What Is and Is Not Cancer?"  Dr. Lundberg reviews the tendency in medicine to label many types of lesions as cancer, and he notes that this is a form of over-diagnosis that can be harmful.  Here are some excerpts:

Cancer cells -- anaplastic, dedifferentiated, capable of autonomous growth, utterly out of control until destroying their host -- are, however, not just one thing. We are learning more every day that cancer is many different diseases, even thousands or tens of thousands of different diseases.

For a long time, it made sense to try to eradicate all cancers, as early and as completely as possible. Mass efforts were launched to find cancers wherever they were and destroy them. Since the earliest cancers seemed to evolve from some identifiable premalignant conditions, wouldn't it make sense to also nip those in the bud? Sounds logical.

But, as with many exuberant efforts, this one got out of control. Many lesions that were called "cancer" really were not cancers at all in behavior, and this fact began to be recognized in large numbers of patients. These unfortunate victims have experienced massive psychological and physical harm and costs without any clear benefits achieved by finding and treating their "noncancers."

Pathologists never can really predict how any one cancer will behave. But after many decades of matching histologic patterns with the natural history of diseases, we are actually pretty good at predicting which lesions will be really bad actors and which seem likely to lie around indolently.

Cure rates from aggressive therapy on those "indolentomas" are 100%. But, so would the outcomes have been of nondiscovery---100% cure of nondisease.

Ceasing to name lesions that are most likely indolentomas by that fearsome word "cancer" is the first step. Almost any patient who hears the word "cancer" applied to their pathologic findings experiences their hair catching on fire. Even if the word is cushioned by physicians with modifiers like "in situ," "early," "precancer," "on the way towards cancer," "caught it in time," and the like, the patent simply wants to get it out of their body. A surgical sell by a surgeon becomes really easy.

Will there be missteps? Certainly. Will there be resistance to change? You bet. Will there be unintended consequences? Most assuredly. Will some of those trial lawyers jump with glee at the possibility of underdiagnosis and new opportunities at lawsuits for "failure to diagnose"? Yes, but we must use our science and professionalism on behalf of the patient's best interests and collectively tell the lawyers and the hospital risk managers to take a flying leap.

Science marches on. Let's listen to it and lead from the front.

Dr. Lundberg cites a recent JAMA article by Laura Esserman and colleagues on this topic.  Entitled,  "Overdiagnosis and overtreatment in cancer: an opportunity for improvement." it is well worth reading.  Here's the abstract:

Over the past 30 years, awareness and screening have led to an emphasis on early diagnosis of cancer. Although the goals of these efforts were to reduce the rate of late-stage disease and decrease cancer mortality, secular trends and clinical trials suggest that these goals have not been met; national data demonstrate significant increases in early-stage disease, without a proportional decline in later-stage disease. What has emerged has been an appreciation of the complexity of the pathologic condition called cancer. The word “cancer” often invokes the specter of an inexorably lethal process; however, cancers are heterogeneous and can follow multiple paths, not all of which progress to metastases and death, and include indolent disease that causes no harm during the patient’s lifetime. Better biology alone can explain better outcomes. Although this complexity complicates the goal of early diagnosis, its recognition provides an opportunity to adapt cancer screening with a focus on identifying and treating those conditions most likely associated with morbidity and mortality.

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