MammotomeA® and EnCorA®: comparison of two systems for stereotactic vacuum-assisted core biopsy in the characterisation of suspicious mammographic microcalcifications alone

The authors sought to compare the diagnostic performance of the Mammotome(A (R)) and EnCor(A (R)) vacuum-assisted breast biopsy (VABB) systems in the assessment of suspicious mammographic microcalcifications. Between January 2011 and July 2012, a total of 169 VABB were performed by stereotactic guidance on a prone table. The Mammotome(A (R)) 11G (S1) or EnCor(A (R)) 10G (S2) probes were used randomly. Sampling time and the number of frustules collected were considered; sensitivity, specificity, diagnostic accuracy, positive and negative predictive value (PPV, NPV) of both procedures were evaluated, considering the final histological examination as reference (B1, B3, B5 lesions underwent surgical excision; B2 lesion were considered confirmed after a negative follow-up of at least 1 year). There were no statistically significant differences between the two groups of patients according to the number of procedures (S1 82/169; S2 87/169), average age, BIRADS category (4a, b), and average size of the lesions. The two systems did not differ statistically for correlation with the final histology (S1 k = 0.94 +/- A 0.06; S2 k = 0.92 +/- A 0.08) and underestimation of B3 lesions or in situ (S1 4.5 %; S2 4.3 %). Sensitivity, specificity, PPV, NPV, diagnostic accuracy of S1 and S2 were also not statistically different. The systems differed only in sampling time (S1 80; S2 63 s), but not in total procedure time. Our study confirms the effectiveness of VABB in the assessment of microcalcifications and highlights the lack of significant differences between the two systems in terms of diagnostic performance.