Peyronie's disease is certainly a possibility - without seeing the lesion, I cannot be sure. Depending on where the plaque is, the penis does not necessarily have to bend.
Other causes would be infection, however without discharge or pain on urination, this would be less likely.
In terms of treatment, suggestions such as vitamin E and continued sexual activity is normally recommended. If there continues to be symptoms, then treatments such as surgery, injection of various medications or radiation therapy can all be considered.
Another diagnostic option would be an ultrasound to evaluate for any masses or problems with blood flow.
These options can all be discussed with a second opinion.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Thanks,
Kevin, M.D.