Reoperation Is Necessary in 20 Percent of Breast Conserving Cancer Surgeries in England — the American Rate May Be Similar — on Talking to Patients about Medical Uncertainty

08 August 2012

Citation

R Jeevan, D A Cromwell, M Trivella, G Lawrence, O Kearins, J Pereira, C Sheppard, C M Caddy, and J H P van der Meulen, Reoperation rates after breast conserving surgery for breast cancer among women in England: retrospective study of hospital episode statistics, British Medical Journal, doi: 10.1136/bmj.e4505 (early online publication, 12 July 2012)

Introduction — this breast cancer study received much less media coverage in the United States than it should have

It is pertinent to every American woman considering having breast conserving cancer surgery.

Why is an English National Health Service — usually called the “NHS” — study relevant to Americans?

America’s frequently blind patriotism tends to forget that some European nations collect and use population-based medical data much more thoroughly and cleverly than we do.

For illnesses that have widely accepted methods of treatment (like breast cancer), European data is highly pertinent to American clinical practice.

The English study’s surprising finding — 20 percent of breast conservation cancer surgery patients require at least one reoperation

After reviewing 55,297 breast conservation cancer surgeries performed between April 2005 and March 2008, the authors wrote that:

One in five women who had primary breast conserving surgery in the English NHS [National Health Service] between April 2005 and March 2008 needed a breast reoperation within three months.

Moreover, among women who had breast conserving surgery as a reoperation, one in seven needed further surgery.

Reoperation was more common among women with a carcinoma in situ component recorded at the time of the primary breast conserving surgery than in those without (29.5% v 18.0%). It was also more common among younger women.

Women should be informed of this reoperation risk when deciding on the type of surgical treatment of their breast cancer.

© 2012 R Jeevan, D A Cromwell, M Trivella, G Lawrence, O Kearins, J Pereira, C Sheppard, C M Caddy, and J H P van der Meulen, Reoperation rates after breast conserving surgery for breast cancer among women in England: retrospective study of hospital episode statistics, British Medical Journal, doi: 10.1136/bmj.e4505 (early online publication, 12 July 2012) (at first paragraph under Discussion and concluding line from Abstract) (paragraph split)

I will explain what “carcinoma in situ” is, during the below discussion.

Breast cancer background

The authors describe breast cancer basics:

Each year, 430 000 new cases of breast cancer are diagnosed in Europe and 250 000 in the United States.

In England, around 45 000 women are diagnosed as having breast cancer annually, and in 2008 58% had breast conserving surgery.

Breast conserving surgery involves removing only part of the affected breast and, when combined with postoperative radiotherapy, produces survival rates similar to those achieved with mastectomy alone for women with invasive disease.

The choice of breast conserving surgery or mastectomy depends on the extent of the cancer, the size of the tumour relative to the size of the breast, its location, and the patient’s preference.

Preoperative chemotherapy may reduce the size of a tumour to allow breast conserving surgery, but a slightly higher risk of local recurrence exists compared with mastectomy.

Two complicating breast cancer factors

The authors note that multifocal disease — meaning cancer which pops up in multiple locations in the breast(s) — occurs in up to 35 percent of breast cancer patients.

Additionally, the extent of noninvasive “cancer in situ” is actually harder to pin down than invasive disease.

Note

Part of this diagnostic and treatment variation is simply due to the fact that invasive disease usually results in aggressive measures to treat it. A presumably much higher percentage of women will elect to undergo mastectomies, rather than breast conserving surgeries, in dealing with it.

Why reoperation numbers are important

Undergoing more operations than retrospectively necessary has costs.

The authors observe that breast conserving surgery may miss some of the cancer. And reoperation will be necessary.

But re-surgery, in turn, can delay cancer treatments like radiation and chemotherapy. The delay may mean that the cancer spreads.

Reoperation generally worsens cosmetic outcomes, even if the second surgery is a complete mastectomy.

Subsequent surgeries also contribute to emotional distress and lengthened recoveries. These have obvious negative impacts on recuperation and employment.

Reoperations add to health care costs.

Note

This may or may not be bad, depending on how economists calculate productivity and gross domestic product. Which demonstrates how challenging economics can be.

Not a problem of sloppy surgeons — instead, it is a consequence of uncertainty in medicine

Diagnosing the extent of some breast cancers is difficult. Statistically, some of these cancers and/or their spread will be missed.

An example — diagnostic uncertainty regarding “carcinoma in situ”

“Carcinoma in situ” is a good example of medical jargon that can obscure the uncertainty that accompanies many diagnoses.

The term is supposed to describe a condition in which cancerous cells have not penetrated what anatomists call the “basement membrane” of one of the body’s tissue systems.

Carcinoma in situ is “good” because it means that abnormal cells have not yet escaped the confines of their origination point. Cancer cells have not yet become “invasive.” They do not threaten the health of other bodily tissues.

In breast cancer, this diagnosis often crops up in regard to “ductal” carcinoma in situ. Though cancer cells are located in one of the breast’s many milk ducts, they have not penetrated the duct’s basement membrane to enter surrounding breast tissue.

One would think that carcinoma in situ would be a comparatively happy thing, given how bad some cancer diagnoses can be. But, according to the study’s findings, the in situ diagnosis noticeably boosts the risk for reoperation because of the false diagnostic certainty that the term can mistakenly convey.

Problems with semantics — “carcinoma in situ”

This term is pathologically more definitive than it probably should be, given current diagnostic abilities. Its semantics would be more accurate, if we attached what scientists and statisticians sometimes call “error bars” or “confidence intervals” to it.

By way of a highly pretended and overly quantified example, a biologically knowledgeable person might say (of an imaginary instance of) carcinoma in situ:

There is an 85 percent probability that the cancerous cells are fully contained within the basement membrane in this one place. (Hence, the term “in situ.”)

But there is a 12 percent chance that they have penetrated the basement membrane by at least 1 centimeter, and perhaps by more. (Meaning that the “in situ” diagnosis is wrong.)

There is also a 2 percent chance that the cancerous cells have invaded most of the breast. (Meaning the diagnosis is even more incorrect.)

And there is a 1 percent chance that these cells have either gone farther or cells in distant places have simultaneously created their own similarly acting cancers. (Meaning that the in situ diagnosis is egregiously incorrect.)

Now remember, I made these numbers up.

They do not describe real life instances of carcinoma in situ. It is impossible to quantify what we cannot see or detect.

These pretend numbers merely illustrate the kind of uncertainty that can accompany medical diagnoses that sound more precise than our current detection abilities actually allow us to be.

That is (presumably) what primarily accounts for the twenty percent English Health Services System’s reoperation rate. Initial surgical attempts undershot the cancers’ actual spreads.

“Gee, Pete, is the diagnosis problem really this problematic?”

Sometimes.

Keep in mind that breast cancer detections usually begin with radiology that reveals an abnormality that is often quite difficult to characterize pathologically.

Biopsies, which are intended to pin down the radiological diagnosis by actually looking at the affected cells, take cell samples in and around the apparently abnormal area. But unless one takes a huge chunk out, one cannot be sure that all the abnormal cells have been scooped up.

Similarly, in cases in which the radiological evidence is confined to one place, we might sample that location, but miss another location that also has cancer cells that are radiologically undetectable.

These uncertainties mean that surgeons are faced with the dilemma of how to advise their patients regarding the scope of recommended surgery:

Take the whole breast?

Less?

If less, how much less?

Patients face the same dilemma. And they are in a bad position because most have to depend on the knowledge of pathologists and surgeons, who are sometimes prone to being more definitive than they should be, biologically speaking.

Note

Medically speaking, strong arguments can be made for the healing power of pretended medical certainty.

Many patients do not like confronting the unknowns that practicing physicians and surgeons have to confront each day. Paternalistic medicine is not dead for very good medical reason.

However, if an autonomy-seeking patient is unknowingly confronted with a paternalistic model physician, she may not become aware of the estimated range of uncertainty.

The moral? — Uncertainty in medicine is unavoidable — but pretending that it is not there is avoidable

That is why the study’s authors recommend that doctors inform their breast conservation surgery patients of the 20 percent reoperation risk that their study revealed.

PeteFree.com

Reoperation Is Necessary in 20 Percent of Breast Conserving Cancer Surgeries in England — the American Rate May Be Similar — on Talking to Patients about Medical Uncertainty