An 83 year old woman underwent an ultrasound guided needle localized excisional biopsy. The submitting pathologist questioned the presence of invasion.
Diagnosis: High grade ductal carcinoma in situ, solid type with disruption secondary to previous fine needle aspiration procedure.
Discussion: The abrupt disruption of the encircling duct wall and associated granulation tissue are paramount in recognizing the changes associated with a previous sampling procedure. Also helpful is the presence of degenerating epithelial cells within the granulation tissue. Evidence of previous core biopsy procedure is usually more easily recognized than fine needle aspiration because of the linear path of reactive changes that a core biopsy procedure creates. Immunohistochemical analysis for myoepithelial markers may be helpful if myoepithelial cells are associated with disrupted fibrovascular cores, but ultimately it is the pattern of disruption that holds the key to the correct diagnosis. Occasionally it takes a bit of delving into the medical record, or a few phone calls to confirm that a previous needle biopsy or aspiration has been performed, as occurred in this case.