Thank you for the additional information.
The first thing which comes to mind is that you could have hydrocele which is collection of fluid in the testicles. However a hydrocele would cause significant swelling and not mild swelling in most cases. A hydrocele is a benign condition in which there is collection of fluid due to a number of underlying issues. This can develop after an infection of any sort in the groin region or even after trauma of any sort. In most cases the hydrocele would subside on its own within 6 months however in some cases you may need treatment which can involve surgery to drain the fluid. This is a small procedure which is done by a urologist and you can even be discharged the same day.
But coming to your question, this does NOT sound like testicular cancer at all, testicular cancer would usually cause a palpable lump over the testicles which would be firm to hard in consistency. So from your description it is unlikely to be testicular cancer at all. However it can be hydrocele or even a spermatocele which is a small cyst which can form on the testicles. This again is a benign condition which usually requires no treatment.
Lastly, if you do have frequency then this size difference can be because of a low grade infection which could be causing epididymitis. this can be diagnosed on a clinical examination and also with the help of a testicular Ultrasound. the treatment is with simple antibiotics
But as far as cancer is concerned, this does not sound to be cancer at all
My suggestion would be to have your GP examine the testicles to see if there is a size difference and if so then he can then run an ultrasound which will diagnose the problem. But let me reassure you once again, with your current symptoms cancer is very very unlikely.
Do you have any more questions?
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