cyst in axilla

Friend with removal of ?cyst in L axilla. Surprised by results of estrogen + ca. Mammo neg and US shows cysts. So far, MRI of left breast neg.  Rt breast MRI this week. Seeing only surgeon now.  Is this an unusual case.  Hx of prior cyst removal and fibrocystic.  Should she have PET?  Who for 2nd opinion-breast surgeon specialist or onocologist. Biopsy of other cysts?  What are we missing?

[CCF-RN,MSN-rf]

Dear haags:  Based on the information you provide, this is a bit unusual.  Are you certain that it was a cyst that was removed in the L axilla?  Could it have been a lymph node?  At this point, a breast surgeon would be the appropriate specialist for her.  It may be premature to do a PET scan but it could be a part of later staging.