Marilyn,

Gary is correct. Post chemo and radiation treatment "candidiasis" or thrush can occur without the characteristic white patches I see in "healthy" patients. One of the reasons for this is that the condition can invade between cells and cell layers. This is due to the fact that the normal tight connection is weak and now can be penetrated by the fungus. Get it looked at and diagnosed. If it is thrush get it treated ASAP.
Systemic thrush is not fun...so treat it early.

Cheers,

Mike