SEATTLEUltrasound (US)-guided Mammotome biopsy is both effective
and safe for sampling breast lesions, Nathalie Duchesne, MD, a staff
radiologist at the Hôpital du Saint-Sacrement, Quebec, said at the 101st
Annual Meeting of the American Roentgen Ray Society (abstract 19). In fact, for
most small lesions, the Mammotome permits complete excision of the lesion.
The low but persisting false-negative rate of core biopsy for small breast
masses was a key impetus for the development of the Mammotome Breast Biopsy
System (Biopsys Medical, Inc, Irvine, California), Dr. Duchesne said.
She and her colleagues prospectively studied the accuracy, feasibility, and
reproducibility of the 11-gauge handheld Mammotome with ultrasound guidance for
the sampling and removal of breast lesions. The Mammotome is inserted beneath
breast lesions, whenever possible, and removes tissue by vacuum.
The researchers chose eight indications for the use of the Mammotome: small
lesions (less than 1.5 cm); lesions that were close to the pectoralis muscle or
implants; lesions that would have been difficult to sample by core biopsy
because of features such as fibrosis; heterogeneous lesions; intracystic solid
masses; lesions suspected of being recurrent in situ carcinoma; lesions with
discordant core biopsy results; and lesions for which the patient expressed a
preference for Mammotome biopsy.
The Mammotome obtains impressively large tissue specimens that patients may
find distressing, Dr. Duchesne cautioned. "We offer the patients virtual
reality glasses for use during the biopsy," she said. "About half of
the patients choose to watch the ultrasound procedure, and the other half
choose to see a movie showing a panoramic view of Canada."
The 61 ultrasound-guided Mammotome biopsies done in the initial 1-year
study period (August 6, 1999, through August 6, 2000) comprised 34% of all
ultrasound-guided biopsies performed at the institution. The lesions ranged in
size from 4 mm to 50 mm. Complete excision was achieved in 55% of all cases and
in 77% of cases with lesions measuring 10 mm or less. A marker clip was
successfully positioned within 1 cm of the biopsy cavity in 70% of cases.