BACKGROUND: Patients with an history of carcinoma of the upper aerodigestive tract are at high risk for recurrence or the development of new tumors in this region. In the majority of follow-up protocols, these patients undergo radiologic and endoscopic evaluation as a means of surveillance for the early detection of recurrence. The brush biopsy-capsule technique represents a noninvasive and inexpensive screening device for this patient population. In the current study, the authors retrospectively assessed the sensitivity, specificity, and predictive value of esophageal brush-capsule cytology for the detection of malignant lesions of the upper aerodigestive tract in this high risk patient population. METHODS: Cytologic specimens from 334 patients with previously treated upper aerodigestive malignancies were available for review. The cytologic, endoscopic, and clinical follow-up of each case were studied over a follow-up period of 3 years. Gold standard was the clinical follow-up for the negative cases (who were not submitted to biopsy) and biopsy for the positive cases. Sensitivity, specificity, and predictive value were calculated. RESULTS: Using cytology 33 malignancies were detected in 25 patients during a 3-year follow-up period. The test was found to have a sensitivity of 88.7% and a specificity of 90.7%. In 66% of cases the malignancies were located in the oropharynx; the others were located in the esophagus. In 70% of cases the malignancies were detected at an early stage. CONCLUSIONS: Esophageal brush-capsule cytology is a simple noninvasive technique that has been proven to be useful in the early detection of metachronous and recurrent neoplasms in the follow-up of patients with previously treated carcinomas of the ear, nose, and throat