Your rose appears to have a stem canker. There are several types of cankers which will cause rose canes to discolored and die. Stem canker enters plants through wounds caused by weather injury, pruning issues, or flower cutting. It also infects plants weakened by black spot or powdery mildew. There are several types of stem canker, but it is not necessary to identify the infecting organism since the treatment is the same for all of them. The bumps or patches enlarge until they surround the cane, and they usually spread to other canes. 

Your plant has a vigorous infections. I suggest you prune it to remove the affected stems. Prune properly, cutting 3 to 4 inches below the diseased area. Cut 1/4 inch above an outward-facing bud node at a 45-degree angle. Disinfect cutting tools afterwards in a 10% bleach water or 70% rubbing alcohol. There is no fungicide to treat stem canker, only vigilance.

The following reference may give you additional information.
https://hyg.ipm.illinois.edu/pastpest/200319c.html 

Here is a complete discussion of canker diseases on roses, along with notes on which species are most resistant, good cultural practices to minimize the disease.
https://ipm.illinois.edu/diseases/rpds/626.pdf\

I hope your rose does well in the future.

You are welcome.