Causes

It's not clear what causes gallbladder cancer.

Doctors know that gallbladder cancer forms when healthy gallbladder cells develop changes (mutations) in their DNA. A cell's DNA contains the instructions that tell a cell what to do. The changes tell the cells to grow out of control and to continue living when other cells would normally die. The accumulating cells form a tumor that can grow beyond the gallbladder and spread to other areas of the body.

Most gallbladder cancer begins in the glandular cells that line the inner surface of the gallbladder. Gallbladder cancer that begins in this type of cell is called adenocarcinoma. This term refers to the way the cancer cells appear when examined under a microscope.