What Causes Painful Swelling Under Left Arm?
Recurrent sebaceous cyst
Detailed Answer:
Hi.
Thanks for your query.
To recapitulate: Male 62 - swelling under left arm - 4 inches from armpit - itching > painful > enlarges > oozes foul smelling red liquid > heals > swelling is gone > comes back...
This looks be a classical infected sebaceous cyst as per the description given by you. Since all the material except the secretary membrane goes out it vanishes to reappear as the secretary wall secretes the sebum which gets infected to have the same process.
I would advise you the following:
Consult a General Surgeon so that when it is enlarged a bit, it can be excised in-toto to have a cure. The material should be sent for the histopathological examination which will give you the most definitive diagnosis and you get rid of the disease also.
I hope this answers your query, please feel free to ask for further relevant queries if you feel that there is a gap of communication.
Regards