We determined the failure rate of stereotactic core needle biopsy (SCNB) and its causes and final outcome in women recalled for calcifications at screening mammography.
We included a consecutive series of 624,039 screens obtained in a Dutch screening region between January 2009 and July 2019. Radiology reports and pathology results were obtained of all recalled women during two-year follow-up.
A total of 3,495 women (19.6% of 17,809 recalls) were recalled for suspicious calcifications. SCNB was indicated in 2,818 women, of whom 12 had incomplete follow-up and another 12 women refused biopsy. DCIS or invasive cancer was diagnosed in 880 of the remaining 2,794 women (31.5%). SCNB failed in 62 women (2.2%, 36/2,794). These failures were mainly due to a too posterior (n=30) or too superficial location (n=17) of the calcifications or calcifications too faint for biopsy (n=13). Of these 62 women, 10 underwent surgical biopsy, yielding one DCIS (intermediate grade) and two invasive cancers (one intermediate grade and one high grade) and another two women were diagnosed with DCIS (both high grade) at follow-up. Thus, the malignancy rate after SCNB failure was 8.1% (5/62). Calcifications were neither depicted at SCNB specimen radiography nor at pathology in 16 women after (repeated) SCNB (0.6%, 31/2,732). None of them proved to have breast cancer at 2 year follow-up.
The failure rate of SCNB for suspicious calcifications is low but close surveillance is warranted, as breast cancer may be present in up to 8% of these women.