Mammary Paget's Disease Secondary to Infiltrating Ductal Carcinoma

Paget's Disease of the breast is named for Sir James Paget, who was one of the great surgeons of his time.  He first reported the disease, which he initially believed to be benign, on the nipples and areola of fifteen women.  He reported the connection with intraductal carcinoma in 1881, and the disease is now considered to be a manifestation of underlying ductal adenocarcinoma that invades the epithelium of the nipple, leading to eczematous changes and erosion.

The prime clue in this case is the history that this is a unilateral condition.  Can jogger's nipple occur unilaterally?  Yes, but you better be darn sure that's al it is.  Close follow up is imperative in these cases, and the best way to get to the answer is to biopsy the lesion.  Short of that, an extremely short follow up after conservative treatment would be your next best option.  Me?  I say biopsy it.  

Extramammary Paget's is outside the purview of this discussion, but perianal and perigenital or axillary rashes that do not resolve deserve a biopsy.  'Nuff said.