False-positive interpretations in respiratory cytopathology: exemplary cases and literature review

Pulmonary cytology has progressed over the past decades because of advancement in imaging studies and increased confidence of pathologists in cytomorphologic diagnosis. It has an overall sensitivity and specificity ranging from approximately 60 to 96%. However, even with the most conscientious laboratories, false-positive diagnoses of malignancy do occur in respiratory specimens, potentially resulting in unnecessary treatment and morbidity. Selected respiratory cytopathology cases with false-positive diagnoses are presented here, along with a review of pertinent literature and a discussion of possible steps to minimize the problem being considered.