Thank you Mike, for the information,
Though higher the level of PSA, the higher the risk but high PSA is not always diagnostic of cancer.
Inflammation & infection of prostate can also cause rise of PSA.
Urine infection can also cause a rise.
But you need to follow up with your urologist & if he suggests biopsy, you should have it.
The lymph nodes with pain under the armpits are unlikely to have any relation with prostate cancer.
There can be an infection/ lymph adenitis or inflammation of the lymph nodes. Folliculitis
is also possible.
There is also possibility of nerve impingement where the pain can radiate down the arms & can increase on moving the limbs.
I would suggest to consult your doctor to have an examination.
You can apply warm moist compress there.
This will help to reduce the inflammation.
I hope this information helps.
I will be happy to assist, if you need any clarification.
Please feel free for any follow up query.