Ultrasonography-guided vacuum-assisted biopsy of microcalcifications: Comparison of the diagnostic yield of calcified cores and non-calcified cores on specimen radiographs.

BACKGROUND

Microcalcifications found on mammography of asymptomatic women can be sampled by ultrasound (US)-guided percutaneous breast biopsy when stereotactic core biopsy is unavailable or unsuccessful. The role of specimen radiograph needs to be reevaluated after US-guided biopsy.

PURPOSE

To compare retrospectively the histological diagnoses of calcified cores and non-calcified cores as depicted on specimen radiographs after a US-guided, 11-gauge, vacuum-assisted biopsy using surgical histology as the reference standard.

MATERIAL AND METHODS

A total of 135 consecutive patients underwent a US-guided vacuum-assisted biopsy for calcifications with malignant histological results from 135 lesions. For each lesion, calcification was identified in at least one core on specimen radiographs. Calcified cores and non-calcified cores depicted on specimen radiographs were separately submitted to the pathology department. The pathological diagnoses of calcified cores and non-calcified cores were compared with final diagnoses at surgical excision.

RESULTS

Of a total of 2049 core specimens that were obtained (mean, 15 per lesion; range, 4-35 per lesion), 794 cores (mean, 5.9 per lesion; range, 1-17 per lesion) contained calcifications and 1255 cores (mean, 9.3 cores per lesion; range, 1-34 cores per lesion) did not contain calcifications. Calcified cores were more likely to enable an accurate diagnosis of cancer as compared to non-calcified cores (67%, 91 of 135 versus 52%, 70 of 135; P = 0.009). A diagnosis of cancer was more likely to be missed with non-calcified cores as compared to calcified cores (16%, 21 of 135 versus 4%, 5 of 135; P = 0.002). There was no difference in the underestimation of malignancy between calcified cores (29%, 39 of 135) and non-calcified cores (33%, 44 of 135) (P = 0.510).

CONCLUSION

Calcified cores depicted on specimen radiographs are more accurate for a diagnosis of cancer as compared to non-calcified cores obtained during US-guided vacuum-assisted biopsy of microcalcifications.