Schneiderian papillomas: a clinicopathologic study of 30 cases.

Schneiderian papillomas are tumors involving the nasal cavity and paranasal sinuses that tend to recur. A long-term clinical follow-up of 30 patients revealed histologically confirmed recurrences in 20 of the 30 patients (67%) and probable recurrences in two additional patients (combined recurrence percentage 73%). Recurrences were most frequent within 1-2 years following primary thrapy and were generally more frequent in patients with more extensive disease and involvement of paranasal sinuses. Histologic features were not helpful in predicting recurrence. One patient in the study (1/30 = 3%) developed a carcinoma at the site of a histologically confirmed benign Schneiderian papilloma after four recurrences over a period of 9 years. No patients died from the tumor. Twenty patients were alive and free of disease at last follow-up; four patients died of unrelated causes and without evidence of disease; four patients are alive with evidence of disease; and two patients died with disease but of unrelated causes. These tumors often pursue a relentless local course requiring multiple surgical excisions but are rarely responsible for death of the patient and seldon undergo a malignant "transformation" (less than 5%).