by Hilary Thomson
Staff writerGram for gram it’s the most diseased organ in the body, say local investigators.
Yet in 1995/96 only $560,000 was spent in Canada for research into prostate
cancer according to a survey of 22 granting agencies.
Second only to lung cancer as a cause of death from cancer among men, it’s
a disease that has been “shrouded in ignorance” according to molecular biologist
Paul Rennie, director of the Prostate Cancer Research Program at the B.C. Cancer
Agency and one of several UBC scientists researching various aspects of the
disease.
Prostate cancer affects one man in eight, a similar incidence to breast cancer
among women. In B.C. of the 3,500 men expected to be diagnosed with it this
year, 550 will die.
Yet finding resources to investigate it is a huge problem, Rennie says. And
with the number of prostate cancer cases expected to double in the next 19 years
as baby boomers age, it’s a problem of growing proportions.
“It’s a crisis of the magnitude that may bankrupt our health care system,”
Rennie says. “There is an urgent need to fund research into prostate cancer
but so far the disease has almost been ignored.”
The walnut-shaped prostate gland surrounds part of the channel that drains
the bladder. When enlarged or cancerous it may compress the channel, obstructing
the free flow of urine.
While the gland’s exact function is not fully understood it is susceptible
to three common diseases: prostatitis (infection of the prostate), enlargement,
called benign prostatic hyperplasia, and cancer.
Although prostate cancer is often associated with older men, about 20 per
cent of patients with the disease are under 65 years old.
Rennie, cancer endocrinologist Dr. Nick Bruchovsky, urologists Dr. Martin
Gleave and Dr. Larry Goldenberg of the UBC Prostate Clinic, and molecular biologist
Colleen Nelson are working on two clinical trials focusing on suppressing the
male sex hormone androgen.
One of the trials explores the limited suppression of the hormone for patients
with localized prostate cancer.
Called neo-adjuvant therapy, it is used prior to surgery or other therapies
to reduce the volume of the tumour, making subsequent treatment more effective.
In advanced prostate cancer, however, the prostate eventually becomes insensitive
to the hormonal treatment. The tumour grows back and is untreatable.
The second trial addresses that problem by withdrawing or suppressing androgen
only intermittently. Preliminary studies suggest that this off and on application
keeps tumours responsive to therapy.
“Prostate cancer is a `silent disease,'” says Rennie. “Often there are no
symptoms for months or years, or until the disease has spread.”
Consequently, about one-half of the cases are discovered only when the cancer
has spread to other parts of the body. What could have been curable in an early
stage then becomes life-threatening.
Geography is just one of a number of the disease’s risk factors.
B.C.’s rate is 32 per cent higher than the average for the rest of Canada.
Researchers relate this difference to the influx of males over 50 years old
who come here to retire.
Despite the higher incidence, B.C. has 16 per cent fewer prostate cancer deaths
than other parts of the country due to consistent treatment policy and the most
active research program in the country, according to Rennie.
Family history is important too. Men whose father or brother have the disease
are three times more likely to develop it than the general population.
Epidemiologist Richard Gallagher is trying to identify the gene that causes
inherited prostate cancer.
The first study in Canada to recruit whole families, Gallagher’s investigation
works with men from 40 B.C.households and is connected with a study of families
across North America. His project recently became part of an international consortium
to find the prostate cancer gene.
UBC researchers at the Institute of Health Promotion Research, as part of
the nationwide Sociobehavioural Cancer Research Network, are also looking at
the psychological and emotional issues surrounding prostate cancer.
This month the Canadian Cancer Society allocated $1.25 million for researching
the disease.
During Prostate Cancer Health and Awareness Week, which started Sept. 14,
urologists, cancer specialists and researchers from UBC and around the province
will be holding forums in service clubs and community centres. Their intention
is to promote the formation of support groups and to help emphasize the need
for research funding. For more information about forums in the Vancouver area,
call (604) 872-4400.
