How much brushing is enough for the diagnosis of lung tumors?

Bronchoscopic investigations of lung tumors require high diagnostic accuracy. Sometimes the combination of brush biopsy with cytologic and histologic examination of forceps-obtained biopsy specimens fails to diagnose tumors. Techniques with a minimum risk and low cost when repeated several times could increase the efficiency of tumor diagnosis and help to avoid rebronchoscopy.

Repeated brush biopsies were done during one bronchoscopic examination in 270 patients with pulmonary neoplasias using a flexible fiberoptic bronchoscope guided by radiographic video fluoroscopy. The results of up to five brush biopsies were compared for their diagnostic sensitivity.

Singly, 68-77% of the specimens showed malignant findings. With repeated brushing, the sensitivity of the diagnostic accuracy increased to 89.6%. In the periphery of the bronchial tree, the sensitivity of brush biopsy was slightly lower in bronchoscopically invisible tumors. In 222 of 242 (91.7%) patients with positive results of brush biopsy, there was agreement in the final typing of tumor morphology.

For routine bronchoscopy, repeated brush biopsy should be done to obtain the highest diagnostic yield.