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Oral malignancies associated with negative transepithelial brush biopsy.

PURPOSE
This study was performed to assess the incidence of negative brush biopsy for oral lesions later demonstrated histologically to be squamous cell carcinoma.


METHODS
All diagnoses of oral squamous cell carcinoma from a university oral pathology service for the period June 2000 through March 2002 were reviewed to determine if any had previously undergone brush biopsy reported to be "negative for epithelial abnormality." Those cases identified were further investigated to determine the time lapse between brush biopsy and definitive tissue diagnosis.


RESULTS
Four cases of brush biopsy negative squamous cell carcinoma were identified from 115 total cases of malignancy (3.5%). The average time from brush biopsy to tissue diagnosis was 117.25 days (range, 5 to 292 days).


CONCLUSION
False negative reports are possible with the oral brush biopsy technique. Persistent lesions should undergo tissue biopsy for definitive diagnosis.