Background: Review of the literature reveals that malignant spiradenomas are rare and may be fatal, and typically manifest as rapid enlargement in long-standing spiradenomas.
Objective: The present tumor was removed 2 months after it was first noted by the patient. A case of what we believe is the earliest stage of malignant transformation within spiradenoma is reported.
Methods: Case report and literature review.
Results: The region with malignant transformation was characterized by nuclear pleomorphism, loss of two cell types, and increased mitotic activity with atypical mitoses. Small infiltrating duct-like structures were seen. The large aggregates and sheets of malignant cells described in long-standing tumors were not seen.
Conclusion: We ascribe the early detection of this tumor to increased public awareness of the importance in seeking early treatment of skin lesions. Histologic examination of this stage may eventually outnumber the now more commonly described latter stages.