Pre-cancerous cells

[Jill]

I am 4 years post op, grade 3, Er/PR negative and HER2 positive ( of course !) Had radiotherapy, chemo and 12 months Herceptin and am generally feeling well. However, this week the nipple on my good breast started to bleed and my surgeon has suggested that it may be pre-cancerous. Just had a mammogram and ultrasound but having a biopsy next week just to check.
Has anyone had this experience? If so what might it mean??
Many thanks
Jill