Thanks for visiting HCM.
FNAC or fine needle aspiration cytology is a safe procedure using the smallest possible calibre of needle (24 or 26 G), going into tissue, aspirating whatever comes out, preparing the slide and getting it examined by a pathologist. And with in a matter of one day, the nature of the lesion is detected.
In your wife's case it appears to be a simple benign cyst
(non cancerous). But to know the exact nature of the lesion, it requires the histopathological examination of the FNAC slided.
The cysts are usually asymptomatic, but occasionally get infected and then there will be pus formation. The treatment is complete removal of the cyst surgically if the patient has got symptoms.
I advise you to go for FNAC. The report will further guide the treatment...