SQUAMOUS-CELL CARCINOMA IN A PATIENT WITH CHRONIC LYMPHOCYTIC-LEUKEMIA - AN INTRAOPERATIVE DIAGNOSTIC CHALLENGE FOR THE MOHS SURGEON

BACKGROUND. Chronic lymphocytic leukemia (CLL) is the most common form of chronic leukemia in the US. CLL patients have an increased risk of developing other malignant neoplasms, especially skin cancer. Lymphom a-associated squamous cell carcinomas (SCCs) tend to behave more aggre ssively and therefore are often treated with Mohs micrographic surgery (MMS). OBJECTIVE. To elucidate the potential difficulty of distinguis hing perineural infiltrates as leukemic infiltrates versus inflammator y infiltrates associated with SCC on frozen tissue sections during MMS . METHODS. This is a case report illustrating a patient with CLL who d evelops a SCC on the posterior ear. MMS was employed to treat the pati ent. Special immunohistochemical stains were performed to help disting uish the type of perineural infiltrate present. RESULTS. The perineura l infiltrate was shown by immunohistochemistry to be leukemic in origi n. Special stains for keratin revealed no residual SCC hidden in the i nfiltrate. CONCLUSION. CLL is a malignancy that primarily effects the elderly population and markedly increases their risk of developing ski n cancers, especially SCC. An intense infiltrate may be present surrou nding the tumor. This case report demonstrates one of the potential ch allenges the Mohs surgeon may face in interpreting histologic frozen s ection. Immunohistochemistry may be helpful in providing a more defini tive answer to this problem. (C) 1998 by the American Society for Derm atologic Surgery, Inc.