Key to cutting cancer rates

Stephen Brincat, chairman of the Radiotherapy and Oncology Department at Sir Paul Boffa Hospital, is rightly concerned about the increasing rate of cancer in Malta (Lifestyle Changes Key To Cutting Cancer Rates, October 12). According to Dr Brincat, addressing lifestyle and environmental factors could have a much bigger impact on the incidence of the disease than screening and new drugs.

About one in three people in Malta will develop cancer at some stage in their lives. One in four will die of cancer. It follows, therefore,that better prevention of cancer, better detection and better treatment and care should be the concern of all. Dr Brincat reckons that about one third of cancer cases are caused by environment or lifestyle factors, including smoking, alcohol consumption, sun exposure, diet and obesity, as well as sexual habits.

Some other factors seen as possible contributors to the development and growth of cancer, which Dr Brincat fails to mention, include unhealthy workplace environments and exposure to air and water pollution, chemicals, pesticides and herbicides. Diesel emissions are a case in point.

As George Debono put it: "It is now general knowledge that diesel emissions are mostly responsible for the cancer risk from air pollutants, but nobody in government seems to care... " (September 25, 2007).

Dr Brincat singles out the incidence of lung cancer among females. According to him, "figures from the National Cancer Registry show that lung cancer among men dropped between 1996 and 2006 but rose in the same decade in the case of females". Dr Brincat opines that the worst in the incidence of lung cancer among females is still to come.

Strangely, A National Cancer Plan For the Maltese Islands - a consultation document published in July 2007 - does not paint such a grim picture of the incidence of lung cancer among females. The document, which covers the same period as that of the NCR, states that lung cancer among Maltese women still has a low profile in both incidence and mortality. Moreover, there has been no statistically significant change in the mortality from lung cancer in females.

Reference is made in the October 12 article to Herceptin, an innovative therapeutic drug that is designed for a minority of women with early-stage breast cancer.

Dr Brincat states that Herceptin "has been found to cut the risk of a relapse by about a half". This comment gives the impression that Herceptin confers a 50 per cent survival advantage. In order to get a clearer picture of the actual benefit of Herceptin, one has to understand the statistical concepts of "relative risk" and "absolute risk".

The quoted figure of 50 per cent is a reduction in relative risk. Relative risk figures are often impressive, yet misleading.

As Ralph Moss, PhD, puts it: "... the benefits of Herceptin in the treatment of breast cancer, while apparently real, are rather small. There was an absolute reduction in the risk of cancer-related events at one year of 5.5 per cent. But through the use of statistical sleight of hand this small benefit has been expressed as a decrease in the relative risk of 50+ per cent or more.

While technically true, this is a highly misleading figure. At the same time, there is a serious problem of cardiac toxicity that undermines any therapeutic advantage of this drug" (Herceptin - Or Deceptin? A paper published in 2005).

Finally, Dr Brincat attributes the year-long waiting list for routine mammograms to the lack of facilities, a shortage of human resources and Malta's size.

Addressing lifestyle and environmental factors that contribute to the cause of cancer is imperative, however, critical to cutting cancer mortality in Malta is the introduction of a Pet (positron emission tomography) scanner as well as new cancer drugs. Additionally, different subspecialty training for consultants should be set up for different types of cancer and space should be allocated for a clinic for integrative medicine at the Department of Oncology of the newly-designated Zammit-Clapp Hospital.

The 2008 budget does not come anywhere near in addressing these key issues in the war against cancer.