News

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LUNG CANCER: MEN

Roughly 85 per cent of lung-cancer cases can be linked to one social evil - smoking. Traditionally, more men than women have smoked. In 1965, for instance, 61 per cent of males over the age of 15 smoked, compared with only 38 per cent of women. But in the latter part of the 1960s, it became increasingly fashionable for women to smoke. At the same time, medical studies were showing that smoking caused lung cancer and a host of other health problems. These two facts led to contradictory trends. Older male smokers were starting to quit, while a growing number of younger women were picking up the habit. In fact, smoking among women didn't start to decline significantly until the early 1980s.

Men killed daily by lung cancer: 29.31

LUNG CANCER: WOMEN

Today, about 22 per cent of men and 16 per cent of women smoke. But lung cancer is one of those diseases that takes decades to develop, and that means the current cancer statistics are a reflection of what was happening in society many years ago. Lungcancer rates among women are continuing to rise. But the rates for men are already on the decline, because they were the first to kick the habit. Another significant trend to watch is teenaged smoking. An equal number of males and females 15 to 19 now smoke-ó 18 per cent. In a few decades, if those figures donít change, an equal number of men and women will be stricken with the deadly disease.

Women killed daily by lung cancer: 25.36

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COLORECTAL CANCER: MEN

Colorectal cancer is a lethal killer, but it doesn't have to be. Early detection can nip it in the bud. The problem is that " it involves a part of the body a lot of people don't like to discuss," says Tony Fields of the Alberta Cancer Board in Edmonton. The tests themselves aren't pleasant. The first is called a fecal-occult blood test. The patient collects small samples of his/ her stool over a period of three days. The samples are then sent to a lab and checked for traces of blood. If blood is detected, then the patient is usually booked for the second level of testing - a colonoscopy. During a colonoscopy, a flexible optical scope is inserted up the rectum and the doctor searches for potentially

cancerous growths. In some cases, the tumour ( if limited in size and location) can be cut out right away. The cure rate is above 90 per cent in cases where the cancer is still confined to the bowel. But if it has spread well beyond the bowel, the survival rate is less than 5 per cent. Several provinces are now working on pilot projects to get full-scale colorectal screening under way. But Dr. Fields thinks " it's a scandal" that it has taken the provinces so long to implement these programs.

Men killed daily by colorectal cancer: 12.6

BREAST CANCER: WOMEN

There was a steady but gradual rise in breast-cancer cases from 1977 to 1992. Since then, the rates have levelled off a bit. Researchers arenít quite sure why the rates inched up, but a wide variety of lifestyle changes could be to blame, says Pamela Goodwin of Mount Sinai Hospital in Toronto. " Things like deferring your first baby until you are older, not having babies, or being less physically active ... are all risk factors."

Although there has been a disturbing rise in cases, the percentage of woman dying of breast cancer has actually declined in recent years. " Most of the reduced mortality is due to two factors: diagnosis at an earlier stage and more effective treatments," Dr. Goodwin says. Indeed, the introduction of screening programs has resulted in more women getting mammograms, breast X-rays that reveal a tumour when it is just a tiny lump ó and hopefully easier to treat. At the same time, new and improved drugs have been added to the medical arsenal to fight the disease and prevent it from coming back. Since the late 1970s, " we have gone from about 35 per cent of breast-cancer patients dying to around 20 per cent," Dr. Goodwin says.

Women killed daily by breast cancer: 14.52

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PROSTATE CANCER: MEN

Screening for prostate cancer went through a major revolution in the early 1990s with the introduction of the PSA test. Many men stepped forward for screening - and for good reason. The test held out the hope of catching the cancer in its earliest stage. Unfortunately, it is far from perfect. The test essentially measures blood levels of prostate-specific antigen, a protein produced by the walnut-sized organ. High PSA levels can be a sign that the prostate has become cancerous. But the test can produce misleading results, so a man with an elevated reading must undergo a more invasive procedure a biopsy, in which a tiny piece of the gland is surgically extracted and examined for signs of cancer. The biopsy can be an unpleasant and unnerving experience.

Even if cancer is found, doctors can't be sure immediately if the patient has a fast -or slow-growing tumour, notes Robert Bristow, head of the prostate-research program at Princess Margaret Hospital in Toronto. In fact, some tumours are so slow-growing that the patient will die of something else before the cancer can kill him. That means some men are having unnecessary cancer therapy after a PSA test. ( Others opt for " watchingwaiting" or " active surveillance" ó they get treatment only if the cancer seems to be getting worse.) These additional cases, which previously would have gone undetected, have helped to push up prostate-cancer rates in recent years. Scientists are trying to refine the PSA test.

Men killed daily by prostate cancer: 11.51

COLORECTAL CANCER: WOMEN

In recent years, the percentage of women diagnosed with colorectal cancer has slowly but steadily declined, but the rate among men has remained roughly the same. Why the difference? Researchers are not sure, but some have speculated the answer may be found in the use of hormonereplacement therapy. Until relatively recently, it was common for women to be prescribed HRT for the symptoms of menopause. The therapy may have provided some protection against colorectal cancer, says Tony Fields, at the Alberta Cancer Board in Edmonton. However, the popularity of HRT has taken a nosedive with the release of several major studies suggesting the treatment can increase the risk of breast cancer and heart disease. If HRT did, in fact, protect against colorectal cancer, " we might see a bit of a rebound [ in colorectal-cancer rates] among women in coming years" because fewer of them are now taking these medications, Dr. Fields says. The risk of developing colorectal cancer also seems to increase with a highcaloric diet and a sedentary lifestyle. " The future does not bode well" as more Canadians are becoming overweight, Dr. Fields says. However, colorectal cancer can be caught early with screening programs, and lifestyle changes can reduce the risk of developing the disease.

Women killed by colorectal cancer: 10.68

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PANCREATIC CANCER: MEN & WOMEN

The pancreas, located deep inside the abdominal cavity, does not give up its secrets easily - even when it is cancerous. In the early stages of pancreatic cancer, there are few obvious signs of the disease ó the person might feel some abdominal pain or nausea. So, by the time doctors suspect cancer, it is often too late. The disease has already spread to other organs. To make matter worse, " it is a very aggressive, rapidly growing tumour,"

Malcolm Moore, an oncologist at Princess Margaret Hospital in Toronto. " It seems to be resistant to the traditional treatments such as radiation therapy and chemotherapy." Even the underlying cause of the disease is a mystery. This year, an estimated 1,800 Canadian women will be diagnosed with pancreatic cancer and 1,750 will die of the disease. The numbers for men are almost the same: 1,700 and 1,650.

Men killed daily by pancreatic cancer: 4.52

Women killed daily by pancreatic cancer: 4.79

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NONHODGKINS LYMPHOMA: MEN

Until the early 1990s, cases of non-Hodgkin's lymphoma - an umbrella term covering a large group of cancers of the immune system ó were on a slow, steady rise. Then they levelled off and now appear to be declining. Why the shifting trend? " That's the million-dollar question and one we would all like to know the answer to," says John Spinelli, a researcher at the B. C. Cancer Agency. Canadian scientists are particularly interested in solving the medical mystery because " Canada has among the highest rates in the world," he notes. " It is likely some environmental factor," he says. Many researchers think the cases are linked to herbicides, such as 2,4D, and other chemical compounds. In recent years, there has been an effort to curb the use of certain chemicals, " which might explain why rates have levelled off," Dr. Spinelli speculates.

Men killed daily by non-Hodgkin's lymphoma: 4.52

OVARIAN CANCER

This year, an estimated 2,300 Canadians will be diagnosed with ovarian cancer and 1,600 will die of the disease. It is so lethal mainly because most women aren't diagnosed until it is well advanced. Initially, there are few symptoms, says Micheline Piquette Miller, an associate professor at the University of Toronto. And those symptoms, such as fatigue and abdominal discomfort, are vague and can be easily confused with those of many other conditions. Furthermore, there is not a reliable screening test. The CA125 blood test is wrong half the time in detecting early-stage ovarian cancer. Left unchecked, the cancer can easily spread to nearby organs, which are tightly packed together in the peritoneal cavity. When the cancer is finally diagnosed, the treatments are of limited value. " While women are initially responsive to the chemo therapeutic drugs, they rapidly develop a resistance to them," Dr. Piquette Miller says. If the cancer spreads to other organs, the five-year survival rate is about 29 per cent.

Women killed daily by ovarian cancer: 4.38