DALLAS--Fine-needle aspiration (FNA) breast biopsies in women
with mammographically apparent, nonpal-pable breast lesions were
deemed impractical due to the high rate of insufficient samples
in a Radiologic Diagnostic Oncology Group (RDOG) study, and were
stopped 19 months into the trial, Etta D. Pisano, MD, said at
the American College of Radiology (ACR) National Conference on
Breast Cancer.
The multicenter study has to date enrolled 5,000 women with specific
mam-mographic abnormalities who would ordinarily have had an open
biopsy procedure. The researchers expect to continue to enroll
patients in the study for at least one more year.
The women were initially randomized into four biopsy groups, to
undergo either stereotactically or sonographically guided core
needle biopsy with or without FNA. Some institutions were not
equipped to provide ultrasound-guided biopsies, and women at these
centers were randomized to stereotactic FNA plus core or stereotactic
core biopsy only.
Crossover was allowed if the lesion was inaccessible by the assigned
system. "An example might be a cluster of calcifications
that could not be seen by ultrasound or a lesion that was inaccessible
by stereotactic biopsy by virtue of its location far back in the
chest wall or close to the nipple," Dr. Pisano said.
Not a Report of Accuracy
Accuracy was determined by either open surgical biopsy or follow-up
mammography at 6, 12, and 24 months. "This is not a report
of the accuracy of either FNA or core needle biopsy," Dr.
Pisano said, "only the insufficient sample rate seen with
FNA."
A preliminary analysis of 398 women undergoing FNA across all
institutions showed that 138 samples (35%) were insufficient,
said Dr. Pisano, of the University of North Carolina School of
Medicine. Sample insufficiency was determined by two expert cytopathologists
who reviewed all FNA specimens: Dr. William J. Frable of Virginia
Commonwealth University and Dr. Nour Sneige of the University
of Texas M.D. Anderson Cancer Center.