00:00
The prostate gland is the largest accessory
gland. It secretes a watery slightly
alkaline fluid. It also secretes fibrinolysin which
liquefies the semen. Whereas, the seminal
vesicle secretes a yellowish, whitish solution
that’s rich in fructose. When you look at
the structure of the prostate gland, there
are separate units illustrated on the diagram.
00:37
Look closely at the urethra, and also, at the
ejaculatory duct coming into the prostatic
tissues. Around that area, immediately around
the urethra, is an area or a zone, if you
like, consisting of what’s labelled there
as mucosal glands. Then there is a middle
submucosal gland layer, and then an outer
peripheral or the main prostatic gland layer.
01:11
These three separate zones are quite significant
as I’ll explain to you in a moment.
01:18
The glandular tissue, even though they are restricted
within these three zones, three separate zones,
and the products are delivered via the ducts
into the urethra, the glandular tissue, if
you look at all through these zones,
is very similar. The epithelium is generally
described as being columnar, but there is
variation in the sort of arrangement of the
epithelium that you often see at various parts
of the prostatic gland. And these epithelial
surfaces can often become nodular, and that
creates a problem. If it occurs in the glandular
tissue immediately around the urethra, then
it can impinge on the lumen of the urethra,
and therefore, make urination a long slow
process. This increases as the males age.
02:15
There is another characteristic also of the
prostate, and that is the presence of prostatic
concretions called corpora amylaceas. These
build up again with age. They become calcified.
02:33
And again, if they build up in a zone immediately
around the urethra, then they can impinge
on the urethra, and therefore again, make
urination a long slow process. Now, these
cells also can become cancerous. Prostate
cancer is the most common cancer in males.
02:59
And it tends to occur in the outer peripheral
main prostatic glands. And there, the cancers
can develop and take over a lot of the mass
of that outer peripheral zone. And that can
be digitally palpated through a rectal examination.
But the problem is that when these cancers
grow within the prostate and maybe even start to
impinge on the urethra, and the male experiences
a long slow urination process, then it’s too late
because by that stage, the prostate cancer
has metastasized. It’s spread to other parts
of the body. The prostate gland secretes many
components of the seminal fluid. One is
prostate-specific antigen. It’s secreted
into the seminal fluid or into the secretions
of the prostate, but a bit of it also leaks
across into the blood stream. So it can be
detected in blood. And in normal individuals,
the levels are lessened about four nanograms
per mil. But in prostate cancers, the secretion
of this prostate-specific antigen can increase.
So, a blood test can reveal higher concentrations
of this prostate-specific antigen or PSA in
the blood. And that is an indication that
there are these cancerous cells present in
the prostate. So, males are encouraged over
a certain age to have a regular blood test
to detect the levels of this PSA.
04:57
Same as females, have a regular Pap smear to detect
the presence of cancer cells that may be exfoliated
from the cervix into the vagina. And similarly,
breasts can be scanned. The mammary gland
can be scanned for the presence of cancer
cells in the breast, because both the change
in the hormonal environment throughout the female
menstrual cycle and genetic predisposition
are risk factors for breast cancer. So there
are these different methods of scanning both
female and male reproductive organs to try
and detect these cancerous events.