No body is perfect

Improved diagnosis of cancer is prompting interventions that may do more harm than good
April 26, 2010

My sister phones me after her latest breast cancer consultation. In four months she has had three lumpectomies on one breast, and more tissue removed from both in a reduction procedure. This time, surely, the lab analysis will show whether she is clear of the disease or will need a mastectomy. “Well,” she sighs, “It’s still not that simple.”

Her experience brought home to me an increasingly troubling aspect of western medicine: that our ability to diagnose diseases at earlier stages can outstrip our knowledge of what best to do about them.

When my sister first found an inflammation in her right breast she went to have it checked. A mammogram revealed it to be harmless, but a scan of her other breast showed suspicious signs. A biopsy confirmed there was a small tumour, surrounded by small patches of ductal carcinoma in situ (DCIS): potentially cancerous cells lining the inside of the milk ducts. The surgeon needed to remove the tumour, the DCIS and a margin of normal tissue around it. But post-operative tissue analysis indicated that, though he had removed the tumour, the margin still contained DCIS. Another lumpectomy was needed. That didn’t solve the problem either.

My sister sought other opinions. Several specialists recommended playing it safe by having a mastectomy of the left breast. But one of them suggested reduction surgery on both breasts, and his view was supported by an expert she consulted privately. She went for the reduction option. Surgery, however, revealed DCIS not only in her left breast but in her right.

Normally, the next move would have been a double mastectomy. But my sister decided to buck the trend, after an in-depth discussion with doctors who were worried that, given the traumatic effects of mastectomy, the “play it safe” instinct of most surgeons was not sufficiently supported by the evidence.

The dilemma is this. DCIS is the most common form of non-invasive breast cancer, yet it remains a mystery. We don’t know how often it turns into invasive cancer. It could be one in five cases, or one in a million. Yet 20 to 50 per cent of detected DCIS cases result in breast removal, even though it’s likely that thousands of women in Britain are living with DCIS and will never get invasive breast cancer.

There is a similar problem with other conditions. Postmortems have shown that around a third of men who die before 60 have cancer in their prostate glands. Most never know and die of something else. Yet blood tests are uncovering more cases of prostate cancer, and one in five men opt to have their prostates removed—even though around a third need to use an incontinence pad for years after surgery, and some two thirds find it difficult to maintain an erection. Meanwhile, MRI whole body scans—a popular means of health screening for the rich—can now detect the tiniest problem. Businesswoman Karren Brady had neurosurgery in 2006 after an MRI scan revealed a brain aneurysm (a ballooning of a blood vessel). Yet one in 20 of us develop brain aneurysms. The chance of one bleeding and causing brain damage is about one in 2,000 annually—and the risks of neurosurgery are greater.

In the US and parts of Europe, sophisticated scans such as MRI are increasingly used as a means of detecting breast cancer. But Monica Morrow, from the Memorial Sloan-Kettering cancer centre in New York, says they result in more biopsies and patient anxiety, with no evidence of improved long-term survival. A 2009 review in the American Cancer Society’s journal concluded that scans before breast surgery tended to change surgeons’ approach from conservation to mastectomy, despite no evidence that breast removal is better for patients. The danger, then, is that we risk potentially dangerous over-treatment because we know something is there—not because treating it makes us live longer or more happily.

This is an understandable problem, born of doctors’ determination to treat, and our reluctance to live with disease. In cancer surgery, surgeons follow national and local guidance on what action to take in specific circumstances. But guidance is lacking where evidence of the risks and benefits of treatment is inconclusive, as in DCIS. In such circumstances, doctors’ natural determination to cure can lead to overtreatment. “We tend to err on the side of caution,” says Michel Douek, consultant breast surgeon at Guy’s and St Thomas’ NHS Trust. “The assumption is you take out the whole thing completely unless there is evidence otherwise. It’s more difficult to tell patients that there’s something there but it’s best not to do anything.”

Yet when there isn’t a “right” answer about treatment, many patients benefit from having that made clear: research by UCL psychologists indicates that if patients share in decision-making with doctors they suffer less from depression and better stick to their treatment. When my sister discovered that mastectomy doesn’t preclude cancer returning, and that many women have regrets after the procedure, she decided against further surgery in favour of radiotherapy and hormone treatment. This has risks too. But 18 months later, despite minor side effects, she is more or less back to normal life, and had the all-clear after her latest check up.

We might be able to cope better with uncertainty if we rid ourselves of the idea that perfection is our normal state. Harvey Eisenberg runs a private scanning service in California. Of the 25,000 people he has scanned, just ten had no abnormalities.

Ironically, it may be cancer itself that helps us come to terms with imperfection. Its incidence is rising because we are living longer, and advances in diagnosis and treatment mean a larger proportion of us will end up living with cancer—often incurable, but controllable with drugs. If living with disease becomes less frightening, we may start to reconsider the surgeon’s default position of “if in doubt, whip it out.”