Core needle biopsy proves safe for patients taking anticoagulants

Radiologists can breathe easier about the risk of patient bleeding and bruising when performing core needle breast biopsies on women who take daily anticoagulant aspirin or therapeutically-in-range warfarin, according to a new study.

In the past, patients were advised to cease anticoagulation therapy for one week before undergoing core needle breast biopsy. Radiologists found, however, that stopping anticoagulation therapy was not always possible because of underlying medical reasons or time constraints. Scheduling a follow-up appointment to perform the biopsy also proved problematic, as patients were more likely to miss their follow-up appointment.

Dr. Patricia Somerville, a radiologist at the Elizabeth Wende Breast Clinic in Rochester, NY, and colleagues retrospectively evaluated the results of 200 women who took anticoagulants and 855 women who refrained from taking anticoagulants.

Stereotactic guided core biopsies using 9-gauge to 14-gauge needles were performed on 631 women who took anticoagulants and 155 who did not use the drugs. Fourteen-gauge ultrasound-guided biopsy was the choice for 218 women in the anticoagulant group and 45 in the nonanticoagulant group. All of the six women who received MRI-guided biopsy involving a 9-gauge needle were taking either aspirin or warfarin.

The study appeared in the October issue of the American Journal of Roentgenology (2008;191:1194-1197).

The researchers discovered that women who take aspirin or other anticlotting agents were significantly more susceptible to bruising than women in the nonanticoagulant group (p = 0.035). Bruising occurred in 34% of women in the anticoagulated group and in 26.5% of the control group.

The average size of bruises that appeared on women who were taking aspirin before a breast biopsy was 32.2 mm in diameter (range: 5 mm to 150 mm). Five percent experienced a combination bruise and bump.

Bruises appearing on women taking warfarin averaged 17.3 mm in diameter (range: 5 mm to 30 mm). One patient (6.2%) reported a lump and bruise. No lumps or bruises were reported for the four patients who were taking Exedrin.

The rate of hematoma development was essentially the same for both groups.

The routine use of lidocaine with epinephrine and localized compression for at least five minutes appeared to aid in hemostasis, according to the researchers. None of the patients required hospitalization or an operative intervention for bleeding. Subsequent therapy was not affected.

Though slightly more bleeding occurred in malignant cases than benign ones, the results led Somerville to conclude that physicians should not be swayed from performing core needle breast biopsy on patients taking daily aspirin or warfarin.

Dr. Chris Flowers, an associate clinical professor of radiology at the University of California, San Francisco Mount Zion Medical Center, said hospital policy at the facility where he works may change, since this study suggests it is safe to perform biopsy when patients are on aspirin or warfarin,

More research, however, is needed on the effect of anticoagulation and core biopsy. Until safety can be determined, it is important to receive patient consent, according to Flowers.

Somerville's study had limitations. It did not assess complete risk profiles of patients or stratify results by age, other medications, lesion size, lesion location, needle size, or number of passes. The study was retrospective, and thus researchers relied on patient self-reporting without confirmation of the physical findings by a medical professional.

For more information from the Diagnostic Imaging archives:

Preoperative breast imaging guides surgical managementAdvanced pathology techniques challenge notions about breast cancerBreast MR shows promise for population at high risk

- By: Rebekah Moan