painful lump and sore hard nipple

I am a 37 year old male. 3 years ago i had advanced testicular cancer and had the testi removed and was recommended to have chemotherapy instead of radiotherapy i got the all clear but left england before my check ups were completed, now for the last three months my right nipple has become very hard and very sore and it feels solid as though there is a mass underneath. should i worry or is it normal ???

[Kamal S Saini, MD, MRCP (UK), DM]

Hi,
You need to get the mass evaluated. In adolescent boys, these symptoms could have been ascribed to developmental gynecomastia, but given your age and medical history, this needs to be evaluated by your doctor.
All the best, and God Bless!