The notion of pleomorphism is used in the field of biology to refer to the development of various structural forms of an organism within the framework of its life cycle. This characteristic usually appears in certain plants.
It is also interesting that you know the etymological origin of the term that we are now going to address. Specifically, it derives from Greek. It is the result of the union of the word “pleon”, which means “full”; from the noun “morphe”, which can be translated as “form”, and from the suffix “-ism”, which is equivalent to “doctrine” and “activity”.
Bacteria , viruses , and certain types of cells can also exhibit pleomorphism. The concept, in its broadest sense, refers to the diversity of forms . If we take the case of bacteria of the genus Mycoplasma , thanks to their pleomorphism they can adopt filamentous or coccoid forms.
Pleomorphism is important for cytology and oncology . Since different studies have found a correlation between the histological morphology of tumors and their level of malignancy, different grading systems have been established.
For the analysis of breast carcinoma , for example, a system that assigns a score to the characteristics of the tumor is usually used. In this context, nuclear pleomorphism is assessed, studying how the size and shape of neoplastic nuclei vary with respect to normal nuclei .
Pleomorphism, for oncological histology, is linked to the variability in the shape and size of nuclei and cells in general. In malignant neoplasms, the cells and their nuclei of a tumor mass change, a characteristic that allows the histological grade to be determined.
In relation to this nuclear pleomorphism and the histological grade that can be used to assess what neoplastic nuclei are, it is necessary to know the score that is assigned. So, in this sense, we can establish the following:
-A 1 for those that turn out to be regular, small in size and uniform that present a minimum variation in shape or size.
-A 2 for neoplastic nuclei that do have a variation in size and shape, but this turns out to be quite moderate.
-A 3 for the aforementioned nuclei that, unlike the two already mentioned, do present a marked and notable variation in the two aforementioned aspects.
Once the relevant score has been given, it will be determined whether the carcinoma is grade 1, grade 2 or grade 3.
There are those who confuse the term pleomorphism with polymorphism. However, it must be made clear that they are different things. Specifically, the second term refers to the existence of two or more different phenotypes in the same species.
The Mexican Microscopy Association , for its part, defines pleomorphism as the doctrine that supports the biological transformation capacity of cells . Therefore, according to pleomorphism, there are cells that can become something different as they grow.