Invasive Paget's Disease of the Breast: Rash or Recurrence?

Paget's disease of the breast is rare among breast cancers. Secondary Paget's disease of the breast presenting as local recurrence is even rarer, with limited published information on the overall prevalence. In this report, we present a case of secondary Paget's disease of the breast presenting as a pruritic rash and skin changes with normal imaging. This patient's case was unique as her presentation involved invasive Paget's disease of the breast presenting as a local recurrence, with a diffuse rash covering the entirety of the right breast including the nipple-areolar complex, pathology examination showing dermal invasion, and a 20-year time interval between her initial treatment and presentation at our institution. Furthermore, diagnostic mammogram and breast MRI revealed no underlying suspicious findings within the breast tissue. In this case, the patient benefitted from mastectomy with removal of the affected skin, resulting in a clear margin and clinically favorable outcome. The patient did well postoperatively, did not receive any systemic adjuvant treatment, and is now under surveillance. Currently, there is insufficient data on the incidence of diffuse Paget's disease of the breast with dermal invasion. It is important to recognize this atypical presentation to ensure timely diagnosis and treatment of affected patients.