As far as I know plants do not get cancers per se.

Cancer in animals is due to a mutation in the programmed cell death of a cell or apoptosis. There are however things in plants that scientist will term "cancer-like tissue". This defect is generally caused by some bacterium, though there are some wasps whose young secrete "cancer inducing" chemicals.

"Cancers" in plants are called galls.

Crown gall disease is probably the most well known. The bacterium Agro bacterium tumefaciens causes the disease.

The microbe carries a plasmid (called Ti. This plasmid enters the infected cell and carries genes which become inserted in the plant's genome. The genes lead to uncontrolled growth of the plant cell, and also cause it to produce and secrete compounds called opines which the bacteria use as a source of food.

In essence, the bacteria create "plant cancers" so they can eat!

A related species, Agro bacterium rhizogenes causes the development of galls consisting of roots (even if present on the stem of the plant).

Now to really get down to your question I am afraid I have a pretty cop-out answer. As far as I know galls are not limited to certain plants though I have only seen galls on woody plants (trees and bushes). There is more to learn from a wonderful site on Wayne Armstrong's Site (Palomar College)

Galls. I hope you find this information useful.