Toronto Globe and Mail
September 26, 2005


Mesothelioma, a rare cancer, affects a growing number of Canadians,

By Carolyn Abraham

When Marilyn Bertrand was six, her big brother returned from his
summer job at Thetford Mines in Quebec's Eastern Townships and
presented her with a fuzzy, white rock from underground.

Marilyn treated it like a doll and took it with her everywhere, even
to bed.

When she was 41 and doctors in Winnipeg wondered how such a young
woman could develop mesothelioma -- a rare and deadly cancer of the
chest cavity -- Mrs. Bertrand remembered her pet rock and how she'd
slept with it. No one at the time realized the full hazards of
cuddling with a hunk of asbestos.

Mesothelioma is the cancer known to strike 20 to 40 years after
exposure to asbestos, the fibrous mineral once considered the magical
fire-retardant in such things as home insulation, break lines and pipe
wrap. The disease is now like a ghost, visiting Canadians in growing
numbers and bringing back old memories.

For Mrs. Bertrand, who died of the disease in 2002, it was the gift
from her brother. For Conservative MP Chuck Strahl, diagnosed in
August, it was changing asbestos break pads on the tree-dragging
yarder in the 1970s.

The cancer develops in the mesothelial cells that form a wax-paper-
thin lining around body parts, such as the pericardium, which holds
the heart, and the peritoneum, which houses the stomach. Often it
sprouts in the pleura, the tissue layer that covers the lungs and
lines the chest cavity, as it has done in the case of Mr. Strahl.

Experts liken mesothelioma to an orphan disease -- poorly understood
and with few specialized drugs to treat it because it's rare. In 2001,
the most recent year for which numbers are available from the Canadian
Cancer Society, 399 Canadians were diagnosed with mesothelioma and 297
people died of it.

The low numbers contribute to mesothelioma's nearly invisible profile.
A situation made worse, said Joseph Testa of the Fox Chase Cancer
Centre in Philadelphia, because the multisyllabic monster is hard to
pronounce. The public often mistakes it for lung cancer. It also tends
to hit older men who have worked with asbestos in mining, shipping or
construction -- "tough guy" types unlikely to seek an early diagnosis
for their pain or organize a walkathon to raise awareness.

Dr. Testa, director of human genetics at Fox Chase and an expert on
mesothelioma, said it seems certain that co-factors, other than
asbestos exposure, contribute to the development of the disease.

Studies suggest only 5 per cent of asbestos miners, for example,
develop mesothelioma. This, Dr. Testa said, suggests that some people
are genetically vulnerable to the damage asbestos causes or that a
virus might act as a catalyst.

But, he said, with outstanding lawsuits from asbestos exposure
victims, not everyone wants to hear that asbestos many not be solely

In roughly 90 per cent of cases, a prior asbestos exposure is clearly
involved in mesothelioma. In fact, Dr. Testa said, a Massachusetts
study found no cases on record before the 1950s, when asbestos had
already been a fixture in industry for more than 60 years.

It's believed mesothelioma may take years to develop after an exposure
because it slowly effects changes to human DNA. One view, Dr. Testa
said, is that asbestos directly damages mesothelial cells. Photographs
have shown that the needle-like asbestos fibres can literally spear a
cell's nucleus.

Another theory is that macrophages, large, patrolling immune cells,
try to attack asbestos fibres and scatter free radicals, or oxygen
particles, that foul up the genetic machinery of the mesothelial

In both cases, Dr. Testa said, cells lose control of their growth and
divide rampantly, increasing the chances further genetic damage will
accumulate. Many years later, a tumour forms.

In other cancers, tumours tend to form as lumps, or balls of cancerous
cells. But the messy tumours of mesothelioma are barely distinct from
the tissue in which they grow, forming, for example, a fibrous shell
like a peel around the lungs.

"It's a thick, hard, gritty kind of tumour," said Michael Johnston, a
thoracic surgeon at Toronto General and Princess Margaret hospitals.
It can leave patients with a crushing feeling in their chests, a
shortness of breath and cough, as fluid and tumours build around the
lungs and creep further along the lining.

Left untreated, Dr. Testa said, most patients will die within six to
eight months of the onset of the disease. Some can make it to two
years or more. In very rare cases, patients with a slow-growing
mesothelioma can survive even longer.

Mike Bertrand said his wife, Marilyn, was given three months to live
after doctors realized in 1994 that her aching back was caused by
mesothelioma. But with rounds of chemotherapy and radiation, Mrs.
Bertrand lived eight more years.

"She was lucky," Mr. Bertrand said.

Experts agree prognosis has suffered because the disease is usually
only discovered in its latter stages when symptoms turn up. But
efforts are under way to develop early blood tests to screen those
with known asbestos exposures.

Dr. Johnston is running a bus between Toronto and Sarnia, which has
one of the country's highest mesothelioma rates, to give former
workers exposed at a petrochemical plant low-dose CT scans.

Doctors have roughly three options to treat mesothelioma. If the
disease appears to grow slowly and seems contained, they may just
drain the excess fluid from the pleural cavity, watch and wait. They
may recommend chemotherapy drugs, or if the cancer appears not to have
spread, radiation.

In a few cases, if the cancer is not aggressive, and the patient is
young and fit, Dr. Johnston said he will recommend a new surgery
research trial. It's a gruelling regimen that involves chemotherapy, a
full-day operation that can include the removal of an entire lung, the
lining of the chest cavity and part of the diaphragm, and a blast of
radiation six weeks later.

(The 48-year-old, marathon-running Mr. Strahl is not a surgery
candidate because his disease has been found in both lungs.)

Barbara Melosky, a medical oncologist at the BC Cancer Agency, is
optimistic, saying people who were exposed to asbestos are becoming
more aware of their risks and that drugs designed to treat other
cancers are being shown as possible therapies for mesothelioma.

Dr. Melosky said the incidence of the disease is increasing, but case
numbers are expected to peak in 2014. By then, research suggests the
asbestos exposures of the past will have caught up to most North

Copyright 2005 Bell Globemedia Publishing Inc.