Reassessing specimen number and diagnostic yield of ultrasound guided breast core biopsy

Kirshenbaum K et al. – Of these lesions, seven were benign and two were malignant. A diagnostic yield of 95% was obtained based on operator estimate of the minimum number of required core biopsies. A high diagnostic yield of 98% was achieved after three biopsy passes and 100% after five passes.

Methods

• A total of 190 consecutive breast mass biopsies were performed using a 14–gauge core biopsy needle under ultrasound guidance.
• Two to six specimens were obtained from each mass and placed in sequential containers.
• Each specimen was evaluated by a pathologist in the order it was obtained and was labeled as “diagnostic’ or ‘non–diagnostic’.
• During the biopsy procedure, the radiologist indicated after which number biopsy he was confident that an adequate diagnostic specimen had been obtained.
• This was based upon real–time visualization of the needle passing through the lesion and whether the specimen sank or floated in formalin.
• These observations were compared with the pathologic diagnostic yield according to specimen number.

Results

• Fifty–eight lesions (30.5%) were malignant, four (2.1%) were atypical, and 128 (67.4%) were benign.
• Histologic diagnosis was obtained after the first specimen in 157 (82.6%) lesions, the second specimen in 172 (90.5%) lesions, the third specimen in 186 (97.9%) lesions, the fourth specimen in 188 (98.9%) lesions, and the fifth specimen in 190 (100%) lesions.
• A histologic diagnosis was made in 90% of the malignant lesions after the first biopsy pass, 95% after the second pass, 98% after the third pass, and 100% after the fourth and fifth passes.
• Nine (4.7%) lesions showed discrepancy between the radiologist’s confidence of diagnosis and pathologic diagnostic yield.

[more...]