Malignant Neoplasms – Neoplasia

00:01 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.

00:22 Bottom line, you think about the differences between benign and malignant, with malignant you go into absolute proliferation.

00:30 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.

00:49 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.

01:03 Whereas in benign, we had well differentiated, well demarcarted. In malignant it will be poorly demarcated.

01:12 If it's in benign, your tumor is most likely well differentiated. In malignant it will be poorly differentiated.

01:18 You will be doing the same thing during your learning. Compare and contrast benign verus malignant.

01:23 Let me give you a couple of examples of terminology and definition.

01:28 There is a term known as pleomorphism. Pleomorphism means various size and shape.

01:35 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.

01:49 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.

02:13 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.

02:24 Malignant neoplasia. If you are thinking about proliferation what part of the cell are you referring to? Good. Nucleus.

02:32 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.

02:46 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.

02:58 Thus, the nuclear to cytoplasmic ratio will be increased. Understood? Now let's move on.

03:06 Because of all that nuclear activity you will find hyperchromasia and prominent nucleoli.

03:12 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.