Cancer is named based on the types of cells or tissues where it

The naming of cancers depends on both the factors.

Explanation:

Different  type of cancers are named on the basis of location of its origin.

-carcinoma, -sarcoma, -blastoma are the terms used as suffix, with the Latin or Greek word for the organ or tissue from where it had originated.

For example: Breast cancer is known as Ductal carcinoma of Breasts.  

[ because it initiates from the tubes(ducts) that carry milk from breasts to the nipples, and carcinoma as suffix ]