From the Guidelines
The negative predictive value (NPV) of breast core needle biopsy is approximately 97-99%, meaning that when a core biopsy result is benign, there is a 97-99% chance that no cancer is present, as supported by the NCCN Guidelines 1. This high NPV is attributed to the accuracy of core needle biopsy, particularly when directed by ultrasound or stereotaxis, with a sensitivity of 97% to 99% 1. However, it is essential to consider factors such as radiologic-pathologic concordance, the type of lesion being sampled, and the technical adequacy of the biopsy, as these can impact the NPV. When there is discordance between imaging findings and pathology results, the NPV decreases significantly, and surgical excision is typically recommended. Core needle biopsies have improved in accuracy with vacuum-assisted techniques and larger gauge needles (14-gauge or larger), which obtain more tissue and reduce sampling error. Despite the high NPV, approximately 1-3% of benign core biopsies may still miss cancer, which is why radiologic-pathologic correlation is essential after every breast biopsy 1. For lesions with high pre-test probability of malignancy, even a benign result should be viewed with caution, and follow-up imaging or repeat biopsy may be necessary to ensure no cancer is missed. Some key points to consider when interpreting the NPV of breast core needle biopsy include:
- The importance of radiologic-pathologic correlation to ensure accurate diagnosis
- The potential for sampling error, particularly with smaller gauge needles or inadequate tissue sampling
- The need for follow-up imaging or repeat biopsy in cases with high pre-test probability of malignancy or discordant imaging and pathology results
- The high sensitivity and NPV of core needle biopsy when performed under ultrasound or stereotactic guidance 1.
From the Research
Negative Predictive Value of Breast Core Needle Biopsy
- The negative predictive value of breast core needle biopsy has been studied in various research papers, with results indicating a high negative predictive value for this diagnostic method 2, 3.
- A study published in 2012 found that the negative predictive value of sonographically guided 14-gauge core needle biopsy of breast masses was 99.4%, with a false-negative rate of 0.1% 2.
- Another study published in 2003 found that the overall false-negative rate for core needle biopsies of the breast was 9.1%, with a lower rate of missed cancer for palpable lesions using ultrasound-guided core needle biopsy (3.6%) compared to core needle biopsy without image guidance (13.3%) 4.
- A study published in 2007 found that the overall sensitivity of core needle biopsy was 94.2%, with a specificity of 88.1%, and a negative predictive value of 95.6% 3.
Factors Affecting Negative Predictive Value
- The negative predictive value of breast core needle biopsy can be affected by various factors, including the type of biopsy method used, the presence of image guidance, and the level of clinical suspicion 4, 3.
- A study published in 2007 found that the underestimation of malignancy was significantly higher for automated core biopsy compared to vacuum-assisted biopsy, with an absolute difference in underestimation of 14% 3.
- The use of image guidance, such as ultrasound or stereotactic guidance, can improve the accuracy of core needle biopsy and reduce the risk of false-negative results 4, 3.
Clinical Implications
- The high negative predictive value of breast core needle biopsy makes it a useful diagnostic tool for assessing breast lesions and reducing the need for surgical biopsies 2, 3.
- However, the risk of false-negative results highlights the importance of correlating core needle biopsy results with clinical and radiologic findings, and considering additional diagnostic tests or surgical biopsies if there is discordance between these findings 2, 4, 3.