Anal/Rectal probs

[paupet]

Had endometrial cancer 13yrs ago..had 28 radiotherapy & 2 brachytherapy treatments. Have since been diagnosed with prd & bam. Last couple of years had thrombin burning itch in rectal area which doc thought was haemorrhoids but coloniscopy found none, had a polyp removed. Am now awaiting colorectal appt & am currently using gnt ointment which isn't really helping. Anyone else had similar? Doctor thinks it may be anal fissures or fistula.