Are all the different cancers really that different or is it all just cancer and we just specify where it formed?
In: Biology
Hi. Med student here, having studied a lot of cancer. I’ll do some simple crash course for you.
Cancer is somewhat of a misnomer, it’s more correct to talk about neoplasm. A neoplasm encompasses benign and malignant processes and gets more of the stuff you think about when it comes to cancer. That being said, neoplasms are fairly intricate and can be broken down into categories.
Neoplasms are usually graded on their histologic/morphologic appearance, that is how they appear on a microscope/with special stains. This is done to gauge how aggressive the tumor is and allows for staging so we can more accurately treat the neoplasm. We also use something called immunohistochemistry stains to understand if there are special markers present on the neoplasm that can clue into whether it’s come from elsewhere in the body or if there are special mutations that allow us to target it with special medications.
Once we have it graded or characterized it’ll put into a variety of categories, such as small cell or adenocarcinoma, each arising from specific tissue (or more accurately are similar to an existing tissue in the body). This will help with understanding if it’s benign and how clinical work up and treatment should proceed. It also lets us know if it’s metastatic, that is it came from another tissue site, such as breast cancer traveling to the lungs.
So with that background, let’s address your question. Yes, all cancers are actually very different. A benign neoplasm like nasal cell carcinoma (skin neoplasm that 1/3 of white people het) will be very different to a glialblastoma (metastatic and invasive brain tumor that kills everyone in less than 2 years). They are very different under microscope, but there are some similar looking cancers that can pop up in different sites (like small cell carcinoma in the esophagus or lungs).
However, there is one guiding principal that you are somewhat right on, that is the origin of the neoplasm. The neoplasms are generally categorizes based on the tissue they look similar to and most likely came from (adenocarcinoma comes from mucous producing cells). That being said this can occur in many different places.
This is also somewhat difficult at times, as the very aggressive (malignant) neoplasms that are the most scary are poorly differentiated, that is the cancer is growing so quickly it no longer resembles any tissue and is just a mass of quickly dividing cells.
That should cover it! There is more in depth stuff like if it’s necrotizing or if it’s infiltrated with immune cells, but that’s more specific for classification and gets away from our general overview.
Hope I helped! Rely if you have questions 😀
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