Move on to malignant neoplasia. If you compare this
picture to the picture that i showed you with benign,
much more difficult to really identify architecture.
And the bottom picture is actually showing you
right there in the middle, where it looks like a darkened
T, what that represents is increased mitotic rate.
Bottom line, you think about the differences between benign and
malignant, with malignant you go into absolute proliferation.
So you have a cell within that cell, in the M phase, that is
going through your prophase, metaphase, anaphase, telophase,
in a very rapid rate. That particular cell right there that you
are seing, and one that you are responsible for indentifying,
is a cell in metaphase, where you have all of the
chromosomes that have lined up in the middle.
That is exactly what you are seing there. And that is
important for you to indentify especially in malignancy,
because these cells are proliferating like crazy. Large,rapid
growth. Necrosis and hemorrhage are often times associated.
Whereas in benign, we had well differentiated, well
demarcarted. In malignant it will be poorly demarcated.
If it's in benign, your tumor is most likely well differentiated.
In malignant it will be poorly differentiated.
You will be doing the same thing during your learning.
Compare and contrast benign verus malignant.
Let me give you a couple of examples
of terminology and definition.
There is a term known as pleomorphism.
Pleomorphism means various size and shape.
You know of a very important pleomorphic tumor especially of
the salivary gland. And it's called your pleomorphic adenoma
that you would find of your salivary, most
likely your parotid. The most common.
So, I wish to point out something to you here. Yes,
pleomorphism tends to be more malignant,
but I told you that there is an exception to everything.
The most common benign tumor of the salivary gland
that we will discuss is called pleomorphic adenoma. The
term pleomorphic means different sizes and shapes,
but the term itself, or the characteristics
could also be applied to benign.
I don't want you to think only black and white.
I am giving you good examples here
such as pleomorphic adenoma of the parotid.
The bottom line is this.
Malignant neoplasia. If you are thinking about proliferation
what part of the cell are you referring to? Good. Nucleus.
That is where the DNA is located. That is where you
would expect to find increased proliferation, right?
With increased nuclear activity, the ratio that you are paying
attention to is an increased in nuclear to cytoplasmic ratio.
Don't memorise that. Understand it. Malignancy, growth
incresed. Proliferation, increased. Cell cycle,
cells in the M phase, lots of mitosis. So,
lots of activity in the nucleus.
Thus, the nuclear to cytoplasmic ratio will
be increased. Understood? Now let's move on.
Because of all that nuclear activity you will find
hyperchromasia and prominent nucleoli.
In the picture on the right, as i showed you, that area
that you find that looks like a darkened middle or the T,
represents increased mitotic rate. High mitotic
activity with abnormal mitotic figures.