What is the difference between bladder and urethral cancer?

Urethra worse: Though bladder and urethral cancer may sometimes have same cell origin, occasionally urethral cancer can be of a type that is more aggresive and invasive and different from that of bladder cancer. Primary urethral cancer as opposed to invasive extension of cancer have different treatments which are more complex and difficult than the usual bladder cancer treatments.

Different cell type: Bladder cancers are usually of transitional (also called urothelial) cell origin, whereas urethral cancers are typically squamous cell cancers with a significant minority presenting as adenocarcinomas (glandular origin). Urethral cancer is comparatively rare. There are a number of unusual exceptions to the above "rule" for both bladder and urethral cancer but this generally holds true.