What does “differentiation” mean?

Q. I’ve Googled and YouTubed this thing to death, and I still can’t grasp the meaning of “differentiation.” It seems the opposite of its definition. To “differentiate” means to recognize what makes something different. (more…)

Do all leukemias arise from hematopoietic stem cells?

Q. I have a quick question on the cell of origin in leukemia. In our pharmacology class, we went through a section on cancer. There was a slide that said leukemia is a tumor of hematopoietic stem cells. But leukemia involves more than just hematopoietic stem cells, right? (more…)

Tumor invasion and metastasis: are they the same thing?

Here are a couple great questions from one of my lovely students regarding invasiveness and metastasis.

Q. I have a quick question on today’s lecture. There is a slide near the end that has a picture of non-invasive carcinoma. For a tumor to be malignant, should it not be invasive? (more…)

More student questions on heme

questionI get so many really good questions from my students. I post them for our class – and from time to time I post them here, too, so everyone can benefit. (more…)

Student questions about neoplasia

Questions about neoplasiaNeoplasia can be a tough concept at first. You hear people talk about cancer all the time – but when we use the word “neoplasia” in pathology, it has a very specific definition, and it’s not the same thing as cancer. (more…)

What’s necrotic in fibrinoid necrosis?


We’ve talked here before about the 6 types of necrosis. One type, fibrinoid necrosis, is sort of an outlier – it’s added at the end of the list of main types of necrosis as if it doesn’t quite belong in the list (Robbins calls it a “special” type of necrosis). (more…)