Letrozole joint pains | breast cancer joints sore

Has anyone else had joint pains caused by letrozole treatment. My friend takes Arimidex and I have been given Femara or Letrozole.

My joints are sore all the time. No swelling - just aches and pains and stiffness every day.

Is this due to my breast cancer treatment? What should I do? Do I need to stop or change to another kind of medication - my oncologist says I need treatment for five years but these pains are terrible.

Any ideas about what to do ?