乌鸦传媒

CHICAGO -- Digital breast tomosynthesis boosted the performance of full-field digital mammography (FFDM) for screening, but the presence of implants reduced its performance, researchers reported here.

The recall rate was 6.3% for tomosynthesis compared with 8% for FFDM among women without implants (P<0.0001), while the recall rate was 5.2% for FFDM for women with implants and 4.1% for women with breast implants who underwent FFDM with tomosynthesis (P=0.040), according to Ethan Cohen, MD, of the MD Anderson Cancer Center in Houston, and colleagues.

Tomosynthesis improved recall rates, cancer detection rates (CDRs), and positive predictive values for recall for all women with and without implants, he reported in a presentation at the Radiological Society of North America annual meeting.

However, statistically significant differences were seen only for recall rates in women without implants, recall rates in women with implants, and PPV1s for women without implants.

The retrospective chart review included all screening exams performed at two community centers from 2011 to 2014. Women with documented breast cancer were excluded.

The examinations included 67,331 FFDM exams and 28,836 FFDM plus tomosynthesis exams in women without breast implants. There were 4,325 FFDM exams in women with implants and 2,579 FFDM plus tomosynthesis studies in women with implants.

Among women without implants, the CDR was 4.1 per 1,000 exams for FFDM and 5.0 per 1,000 exams for FFDM plus tomosynthesis (P=0.045). Among women with implants, the CDR was 1.8 per 1,000 exams compared with 2.7 per 1,000 exam for FFDM plus tomosynthesis (P=0.46). Cohen noted that the study may have been underpowered to detect a statistical significance in the latter group.

For women without and with implants, positive predictive values for recall were 5.1% and 8.0%, respectively (P<0.0001), the authors reported.

"The benefit of tomosynthesis has been incompletely studied in screening mammography patients with implants," they concluded. "This research suggests that tomosynthesis is useful for screening women with implants in addition to those without implants."

Stamatia Destounis, MD, of Elizabeth Wende Breast Care at the University of Rochester in New York, told 乌鸦传媒 that tomosynthesis does offer more views of the breast tissue, "but the same problem that plagues conventional mammography [in women] with implants is also going to affect tomosynthesis because the implants are in the way."

Destounis, who was not involved in the study, added that "if you are having trouble seeing the tissue because the implant is in the way, and you think that tomosynthesis is going to help you see the tissue, that may not be the case. And if the implants have been there for a long time, they may be encapsulated, they may be fibroses, they have scars, they are not mobile, and you cannot move them out of the way."

She pointed out that women with implants who come for screening most likely will have had the implants for some time, and suggested that ultrasound may prove more helpful in these women.

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