Another Contender for Breast Tomosynthesis? Finally.

Siemens is looking to enter the U.S. tomosynthesis market with an announcement last week that the company recently submitted a premarket approval application (PMA) to the U.S. Food and Drug Administration (FDA) for the MAMMOMAT Inspiration with breast tomosynthesis option.

While Siemens, and other vendors, already operate tomosynthesis outside of the U.S., Hologic is the only vendor that operates a FDA-approved breast tomosynthesis option in the U.S. A market Hologic has dominated since 2011.

The PMA submission provided clinical study results and manufacturing information, Siemens said in a release. Tomosynthesis is considered a class III device, which means that data from a clinical trial is required to measure safety and effectiveness. According to the FDA, the PMA process includes four steps: determine completeness of the application; in-depth scientific, regulatory and quality system review by the appropriate FDA personnel; review recommendation by appropriate advisory committee (panel review) and final deliberations.

The FDA will not comment on applications currently in process, but Siemens would be notified of whether the application was accepted and will continue the submission process (step 1) within 45 days of submitting the PMA. The entire process is expected to take 180 days, at the end of which, Siemens would be notified whether the system is approved.

The breast tomosynthesis option has been designed as an add-on for the MAMMOMAT Inspiration digital mammography system. The tomosynthesis mode would acquire 25 projection views over an angular range of 50 degrees to produce 3D digital breast tomosynthesis images, which are intended to be suitable for screening and diagnosis of breast cancer, Siemens said in a release.

Here, Laurie Fisher, vice president of X-ray products at Siemens Healthcare, provided Diagnostic Imaging with more information on entering the breast tomosynthesis market.

What is the benefit of breast tomosynthesis?
From a technical perspective, conventional 2D mammography produces a single, flattened breast image, while digital breast tomosynthesis (DBT) acquires breast images from several angles. These multiple-angle breast images are combined to create a 3D rendering of the entire breast.[[{"type":"media","view_mode":"media_crop","fid":"25580","attributes":{"alt":"","class":"media-image media-image-right","id":"media_crop_1149901754688","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"2350","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"line-height: 1.538em; height: 300px; width: 200px; border-width: 0px; border-style: solid; margin: 1px; float: right;","title":" ","typeof":"foaf:Image"}}]]

From a manufacturer standpoint, what happens next? 
We await a response from the Food and Drug Administration.

Hologic had its first FDA-approved breast tomosynthesis system in 2011. Why did it take Siemens so long to compete?
The Siemens Breast Tomosynthesis option has been commercially available and used clinically for diagnosis since 2009 in Europe, Asia and South America. In the U.S., the FDA classifies breast tomosynthesis as Class III, meaning that data from a clinical trial is required to measure safety and effectiveness. Class III devices require a PMA submission to the FDA for approval. 

As a priority, we focused our R&D efforts on delivering low-dose technology for the U.S. market.  As evidence of this investment and focus, Siemens introduced two digital mammography systems: the MAMMOMAT Inspiration and the MAMMOMAT Inspiration Prime Edition, the latter of which allows for up to 30 percent less dose.

What place does breast tomosynthesis have in the future of breast imaging?
There is controversy among radiologists regarding the role breast tomosynthesis will play in the future. A similar controversy ensued when digital mammography was introduced to the market. Therefore, further clinical evidence will be required – but the debate is whether the potential for improved cancer detection exists.

Final thoughts?
With the introduction of our low-dose mammography systems and now with the PMA submission of Siemens Breast Tomosynthesis, Siemens demonstrates its long-standing and ongoing commitment to innovation in women’s health.