Since this paper published in The Breast Journal eight years ago that documents the concern, it is well known that there can be a local recurrence of breast cancer in a core needle biopsy site due to tumor seeding of the needle tract:

“Since the core needle biopsy exit site represents a potential area of malignant seeding and subsequent tumor recurrence, we recommend excising the stereotactic core biopsy tract at the time of definitive surgical resection of the primary tumor.”

This issue was addressed more extensively in a more recent study published in the journal Breast Cancer that set out to…

“…assess the risk of needle tract seeding of breast cancer from cytological results derived from core needle wash material.”

The investigators examined the tissue washed off of the outside of the needle to determine if there were malignant cells that would represent positive needle track seeding of breast cancer. Their conclusion:

“…the incidence of positive cases of cytology derived from ultrasonographically guided breast core needles’ wash material was 65%.”

The same investigators then published a follow-up study in the same journal last year to compare the standard core needle biopsy with directional vacuum-assisted biopsy for the risk of needle tract seeding:

“A disadvantage of the image-guided core needle biopsy is that needle tract seeding may occur and affect the local recurrence and overall survival rates of patients after breast-conserving surgery, although the chance is small. The purpose of this study was to compare the potential risk of needle tract seeding of breast cancer from ultrasonographically guided needle biopsies that were performed with a directional vacuum-assisted device and an automated core needle gun.”

What did the data show?

“There were significantly fewer positive cytological findings derived from the needle wash material with the directional vacuum-assisted device (33%) than with the automated core needle gun (69%).

Their clear conclusion:

“The use of the directional vacuum-assisted device significantly decreases the potential risk of needle tract seeding of breast cancer after an ultrasonographically guided needle biopsy.”

Hopefully your doctor is aware of this, but it certainly doesn’t hurt to ask. Although a vacuum-assisted device doesn’t obviate the need to excise the needle tract if a malignancy requires a surgical intervention, the less abnormal cells spread around the better.