Bizarre epithelial atypia of the sinonasal tract after chemotherapy

Certain chemotherapeutic agents can induce bizarre epithelial atypia. The l ower respiratory tract is a frequently targeted site, but similar changes h ave not been described adequately in the sinonasal tract. Unfamiliarity wit h these changes could potentially cause confusion with an infectious or neo plastic process. All biopsies of the sinonasal tract at The Johns Hopkins H ospital were reviewed prospectively over a 54-month period. Eleven cases wi th bizarre atypia of the respiratory epithelium formed the basis of this st udy. The medical records of these patients were reviewed. The specimens wer e from ii patients who had previously undergone chemotherapy and bone marro w transplantation for acute myelocytic leukemia(n = 5), multiple myeloma (n = 3), acute lymphocytic leukemia (n = 2), and chronic myelocytic leukemia (n = 1). Although the chemotherapy regimens were highly variable, all inclu ded one or more of the alkylating agents (cyclophosphamide, n = 11; busulfa n, n = 5; melphalan, n = 1). In all 11 patients, biopsies were acquired to rule out invasive fungal sinusitis. The atypical epithelial changes include d striking nuclear enlargement, hyperchromasia, and pleomorphism, Sometimes these changes were full thickness and were associated with squamous metapl asia. Two of eight cases evaluated by frozen section were misinterpreted in itially as high-grade epithelial dysplasia. Certain chemotherapeutic agents can induce striking epithelial atypia in the sinonasal tract. These change s should not be interpreted as neoplastic in nature, a potential pitfall in the frozen section evaluation of a destructive nasal process in oncology p atients.