Cancer: A case of over-diagnosis

The most common cancer causing death among women all over the world is breast cancer. It’s true in India, too. There is evidence that the incidence of breast cancer is increasing in India, and inching upwards to match numbers in Western countries. There is no doubt that early diagnosis and timely treatment can save lives.

But how to do it?

There has been a ready answer for the past many years: mammography. Mammography is a type of X-ray of both breasts. Primarily a screening test, it can be used to direct needles for biopsies and for follow ups also.

Screening by mammogram has been routine in most developed countries for decades. The age and frequency varies among countries. For example, in the US, a common recommendation is to start screening at the age of 50, once every year. Most studies indicate thatthe approach increases survival rates by   20 to 30 per cent. This made almost every doctor to endorse mammography.

However, there has been a change in attitude among experts in recent years. In at least some quarters, the question is being asked, has there been an mammography overdrive?

It has been noticed that very small  cancers or cancers that may actually lie dormant and may not have caused any trouble during a woman’s lifetime have been picked up by extensive screening, and subjected to surgery, chemotherapy and radiation.

It is not that patients who don’t have cancer are treated. But patients who have cancer that may not have become clinically apparent during her lifetime may have been diagnosed and treated. This is a novel problem, arising due to advances in medicine. We see this in thyroid cancer, and also in cancers of the prostate gland. The issue is in the limelight because recently the Swiss Medical Board recommended that screening by mammography be stopped. Currently, though, other Western countries continue with the screening policy.

In India, most professional bodies do not recommend routine screening due to several reasons:

*Incidence of the disease is still less than in the West.

*Mammography is an advanced, expensive tool and requires experts to do the test and interpret the data.

*Due to these reasons, it is not cost-effective.

So, right now, screening is not recommended in India as a routine. But if one has a history of close relatives having had breast cancer, it may be required. An expert doctor in the field can advice one regarding this. Breast self examination and clinical examination by a doctor are the other methods of screening. They are cheaper, and can be easily done. But they are not proven to be effective enough, and there are no specific guidelines. The only guide available is to educate women regarding breast cancer. If they notice a lump, ulcer or thickening in the breast, or unusual nipple discharge, they should consult a doctor.

(Dr Jimmy Mathew is a senior consultant surgeon and a member of INFO CLINIC INDIA, an organisation dedicated to public health education)