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  1. News and Events (Radiation-Emitting Products)

Letter to Manufacturers of Linear Accelerators, Radiation Therapy Treatment Planning Systems, and Ancillary Devices

(April 8, 2010)

Dear official contact:

The Food and Drug Administration’s (FDA) records have identified you as the “Official Correspondent” to the medical device manufacturer stated above. Please ensure that the following message is relayed to the most responsible individual at the medical device manufacturer.

In order to reduce the number of under-doses, over-doses, and misaligned exposures from therapeutic radiation the FDA is taking several steps to improve the safety and safe use of certain radiation therapy devices. Analyses of Medical Device Reports (MDRs) revealed device problems that appear to be the result of faulty design or use error that could be mitigated by the incorporation of additional safeguards. Between December 31, 1999, and February 18, 2010, FDA received 1,182 MDRs associated with the use of radiation therapy devices. Of these MDRs, linear accelerators accounted for 74%, radiation therapy treatment planning systems (RTP) accounted for 19%, and ancillary devices (e.g., radiation therapy simulators) accounted for 7%. The most frequently reported device problems were computer software issues, use of device, and incorrect display. In some reports, the manufacturer was unable to determine or identify the problem and reported the problem as “unknown.”

A separate analysis of these MDRs for software problems identified 362 MDRs. Of these MDRs, linear accelerators accounted for 66%, RTP accounted for 29%, and ancillary devices accounted for 5%.

It is important for manufacturers to investigate the cause of nonconforming product and analyze factors in addition to use error as part of Corrective and Preventive Actions (CAPA). Such analysis may include an assessment of the correlation between product user interface, controls, or user information and use error.

FDA plans to hold a public workshop on radiation therapy treatment planning, medical linear accelerators, and ancillary devices. Additional information will be published in a Federal Register notice. Topics will include:

  • New safeguards and other special controls to improve safety;
  • Possible changes in premarket device testing to provide appropriate assurances of safety and effectiveness, particularly for software; and
  • Premarket review of all modifications to software.

FDA encourages manufacturers to attend the public workshop to discuss these issues.

In light of the MDRs concerning these products, and the increasing complexity of these technologies, the submission of a special 510(k) or a third party review (see § 523(a)(3) of the Federal Food, Drug, and Cosmetic Act (21 U.S.C. 360m)) may not be appropriate for your device. Manufacturers who have questions about the appropriate submission type (e.g., special 510(k) or traditional 510(k)) for their device should contact Donald J. St.Pierre, Deputy Director for New Device Evaluation, OIVD, CDRH, (301) 796-5454, don.st.pierre@fda.hhs.gov.

FDA believes these steps and early communication between FDA and manufacturers will help mitigate current risks, including use errors, and reduce future risks associated with linear accelerators, radiation therapy treatment planning systems, and ancillary devices, and thereby result in safer and more effective radiation therapy. We look forward to working with you on this important public health issue.


Jeffrey Shuren, M.D., JD.
Center for Devices and Radiological Health

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