510(k) · Cleared
Recalled · Class II · 2020Tomotherapy Treatment System
Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly
Accuray Incorporated · IYE Accelerator, Linear, Medical
Cleared on Aug 29, 2012 as substantially equivalent to K112776 (Tomotherapy Incorporated, 2011) after a 58-day review. Its family tree reaches back 10 generations to 1992. 10 later devices descend from it. It has been recalled 8 times.
- Decided
- Aug 29, 2012
- Review
- 58 days
- Class
- Class II
- Product code
- IYE
- Recalls
- 8
- Predicates
- 1
Its longest line of descent runs back 10 generations to K914698 (1992). 26 ancestors in all, the oldest K882729 (1988). 10 later devices descend from it, 5 citing it directly.
- Root · 10 generations backK914698 Setup Computer with Software V-1261,62 and 63K.S., Inc. · 1992
- 6 generations between
- 3 generations backK060912 Modification to: HI-Art SystemTomotherapy Incorporated · 2006 · Recalled
- 2 generations backK082005 Modification to HI-Art Treatment SystemTomotherapy Incorporated · 2008 · Recalled
- 1 generation backK112776 Tomotherapy Treatment System Fast OptimizerTomotherapy Incorporated · 2011
- This deviceK121934 Tomotherapy Treatment SystemAccuray Incorporated · 2012
- Descendant · cites it directly · 3 of its ownK161146 Radixact Treatment Delivery SystemAccuray Incorporated · 2016 · Recalled
- Descendant · cites it directly · 2 of its ownK161136 Precision Treatment Planning SystemAccuray Incorporated · 2016
- Descendant · 2 generations on · 1 of its ownK202412 ClearRT Helical kVCT for the Radixact Treatment Delivery SystemAccuray Incorporated · 2020
- Descendant · 2 generations on · 1 of its ownK171086 Accuray Precision Treatment Planning SystemAccuray Incorporated · 2017
- Descendant · 3 generations on · 0 of its ownK223159 Radixact Treatment Delivery SystemAccuray Incorporated · 2023
Show all 10 generations
- Root · 10 generations backK914698 Setup Computer with Software V-1261,62 and 63K.S., Inc. · 1992
- 9 generations backK980904 Mucheck Monitor Unit Validation ProgramMedical Dosimetry Services, Inc. · 1998
- 8 generations backK990833 Dose Calc, Model VS. 1.02Integrity Medical Software, Inc. · 1999
- 7 generations backK993923 Adac PINNACLE3TM Radiation Therapy Planning SystemAdac Laboratories · 2000
- 6 generations backK013673 HI-Art SystemTomo Therapy, Inc. · 2002
- 5 generations backK033347 Modification to: HI-Art SystemTomotherapy Incorporated · 2003
- 4 generations backK042739 HI-Art SystemTomotherapy Incorporated · 2004
- 3 generations backK060912 Modification to: HI-Art SystemTomotherapy Incorporated · 2006 · Recalled
- 2 generations backK082005 Modification to HI-Art Treatment SystemTomotherapy Incorporated · 2008 · Recalled
- 1 generation backK112776 Tomotherapy Treatment System Fast OptimizerTomotherapy Incorporated · 2011
- This deviceK121934 Tomotherapy Treatment SystemAccuray Incorporated · 2012
Showing 5 of 10 descendants. See all descendants
Descendants cleared per year
Most influential descendants
Showing 5 of 10 · See all- K161146Radixact Treatment Delivery SystemAccuray Incorporated · 2016 · cites it directly3descendants
- K161136Precision Treatment Planning SystemAccuray Incorporated · 2016 · cites it directly2descendants
- K202412ClearRT Helical kVCT for the Radixact Treatment Delivery SystemAccuray Incorporated · 2020 · 2 generations on1descendant
- K171086Accuray Precision Treatment Planning SystemAccuray Incorporated · 2017 · 2 generations on1descendant
- K223159Radixact Treatment Delivery SystemAccuray Incorporated · 2023 · 3 generations on0descendants
View FIG. 1 as a table
Line of descent and top descendants
| Generation | Number | Device | Applicant | Decided | Recalls |
|---|---|---|---|---|---|
| −10 | K914698 | Setup Computer with Software V-1261,62 and 63 | K.S., Inc. | 1992 | — |
| −9 | K980904 | Mucheck Monitor Unit Validation Program | Medical Dosimetry Services, Inc. | 1998 | — |
| −8 | K990833 | Dose Calc, Model VS. 1.02 | Integrity Medical Software, Inc. | 1999 | — |
| −7 | K993923 | Adac PINNACLE3TM Radiation Therapy Planning System | Adac Laboratories | 2000 | — |
| −6 | K013673 | HI-Art System | Tomo Therapy, Inc. | 2002 | — |
| −5 | K033347 | Modification to: HI-Art System | Tomotherapy Incorporated | 2003 | — |
| −4 | K042739 | HI-Art System | Tomotherapy Incorporated | 2004 | — |
| −3 | K060912 | Modification to: HI-Art System | Tomotherapy Incorporated | 2006 | 4 |
| −2 | K082005 | Modification to HI-Art Treatment System | Tomotherapy Incorporated | 2008 | 7 |
| −1 | K112776 | Tomotherapy Treatment System Fast Optimizer | Tomotherapy Incorporated | 2011 | — |
| 0 (this device) | K121934 | Tomotherapy Treatment System | Accuray Incorporated | 2012 | — |
| +1 | K161146 | Radixact Treatment Delivery System | Accuray Incorporated | 2016 | 1 |
| +1 | K161136 | Precision Treatment Planning System | Accuray Incorporated | 2016 | — |
| +2 | K202412 | ClearRT Helical kVCT for the Radixact Treatment Delivery System | Accuray Incorporated | 2020 | — |
| +2 | K171086 | Accuray Precision Treatment Planning System | Accuray Incorporated | 2017 | — |
| +3 | K223159 | Radixact Treatment Delivery System | Accuray Incorporated | 2023 | — |
Other ancestors by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 1988 | 1 | 0 |
| 1989 | 1 | 0 |
| 1990 | 1 | 0 |
| 1992 | 1 | 0 |
| 1993 | 1 | 0 |
| 1994 | 4 | 0 |
| 1996 | 1 | 0 |
| 1998 | 4 | 0 |
| 2001 | 2 | 0 |
Descendants by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 2015 | 1 | 0 |
| 2016 | 2 | 0 |
| 2017 | 2 | 0 |
| 2018 | 1 | 0 |
| 2020 | 2 | 0 |
| 2021 | 1 | 0 |
| 2023 | 1 | 0 |
Sources: FDA 510(k) database (decision fields), the FDA summary (predicates and indications), FDA recall and enforcement reports, and MAUDE; processed by 510(k) Report. Verify on FDA.gov · Methodology and accuracy.
Planning a device in IYE? A 510(k) Report weighs predicate choices, recall history and review times for a new device like this one.
Top candidate predicates for a new IYE device
- #1 K252977 Halcyon, Ethos Radiotherapy System (5.0)score 18.8 · 18 generations · no Class I recall
- #2 Held for the reportin the report
- #3 Held for the reportin the report
What was it cleared against? (1)
Devices the submitter claimed this one is substantially equivalent to (*), and reference devices cited for a specific test or feature (†), as written in the FDA summary.
| Type | Number | Device | Decided |
|---|---|---|---|
| * | K112776 | Tomotherapy Treatment System Fast Optimizer | 2011 |
What descends from it? (10)
5 later devices cite it directly; ranked here by how many devices descend from each in turn.
Has anything in its family been recalled? (0 Class I)
Recalls of this device
| Date | Class | Recall | Root cause | Reason |
|---|---|---|---|---|
| Dec 10, 2020 | Class II | Z-0784-2021 | Software Design Change | "MLC tickle error" may result in the delivered dose to effectively rotate from the planned dose. |
| Nov 17, 2017 | Class II | Z-0288-2018 | Software design | Uncontrolled couch Z-axis movement (descent) |
| Nov 17, 2017 | Class II | Z-0289-2018 | Software design | Uncontrolled couch Z-axis movement (descent) |
| Nov 17, 2017 | Class II | Z-0286-2018 | Software design | Uncontrolled couch Z-axis movement (descent) |
| Nov 17, 2017 | Class II | Z-0287-2018 | Software design | Uncontrolled couch Z-axis movement (descent) |
| Nov 21, 2014 | Class II | Z-0507-2015 | Software design | Accuray has become aware of a potential safety issue related to the TomoTherapy Treatment System caused by a failure to monitor the jaw position after a jaw error occurs. This may result in an incorrect jaw position during treatment… |
| Jul 17, 2014 | Class II | Z-2239-2014 | Software design | Accuray is voluntarily recalling TomoTherapy H Series software versions 1.2.0, 1.2.1 and 1.2.2 (Hi-Art¿ 4.2.0, 4.2.1 and 4.2.2). Accuray has identified potential safety issues (anomalies) with these software versions. |
| Jul 16, 2014 | Class II | Z-2240-2014 | Software design | Accuray is voluntarily recalling TomoTherapy H Series software versions 2.0.0 and 2.0.1 (Hi-Art¿ 5.0.0 and 5.0.1). Accuray has identified potential safety issues (anomalies) with these software versions. |
The 5 latest of 8 recalls; the web page lists all.
No ancestor or descendant has a Class I recall.
What does this lineage say?
- The line of descent spans 20 years and passes through 7 companies; a new generation was cleared every 1.8 years on median.
- 6 of the 26 ancestors have a recall of any class.
- Of its descendants, K161146 (Accuray Incorporated, 2016) has gone furthest, with 3 descendants of its own.
How does its category compare?
All IYE devicesIYE Accelerator, Linear, Medical: FDA decisions, review times, recalls and adverse event reports over 20 years. 2012, this device’s year, is highlighted.
FDA decisions per year · IYE
12in 2025
2026 to Oct 25, outlined.
Median 510(k) review, days · IYE
170in 2025
Receipt to decision; years with fewer than 3 clearances left blank.
Recalls per year · IYE
1in 2025
Class I (0 since 2007) Class II/III not classified
Adverse event reports per year · IYE
101in 2025
MAUDE reports naming product code IYE, not matched to any one device; reports are not rates.
View these four charts as a table
| Year | Decisions | Median 510(k) review, days | Recalls (Class I) | MAUDE reports |
|---|---|---|---|---|
| 2007 | 23 | 44 | 78 | 155 |
| 2008 | 14 | 69 | 49 | 114 |
| 2009 | 20 | 63 | 22 | 174 |
| 2010 | 23 | 74 | 27 | 246 |
| 2011 | 11 | 94 | 73 | 280 |
| 2012 | 28 | 106 | 20 | 128 |
| 2013 | 18 | 88 | 11 | 96 |
| 2014 | 20 | 100 | 14 | 124 |
| 2015 | 20 | 108 | 8 | 100 |
| 2016 | 21 | 97 | 7 | 97 |
| 2017 | 23 | 94 | 7 | 125 |
| 2018 | 21 | 58 | 7 | 85 |
| 2019 | 19 | 83 | 2 | 91 |
| 2020 | 20 | 67 | 4 | 74 |
| 2021 | 19 | 86 | 5 | 68 |
| 2022 | 12 | 172 | 3 | 66 |
| 2023 | 18 | 129 | 7 | 128 |
| 2024 | 9 | 239 | 1 | 81 |
| 2025 | 12 | 170 | 1 | 101 |
| 2026 | 14 | 120 | 4 | — |
What is it indicated for?
The TomoTherapy Treatment System is intended to be used as an integrated system for the planning and precise delivery of radiation therapy, stereotactic radiotherapy, or stereotactic radiosurgery to tumors or other targeted tissues while minimizing the delivery of radiation to vital healthy tissue. The megavoltage x-ray radiation is delivered in a rotational, non-rotational, modulated (IMRT), or non-modulated (non-IMRT/three dimensional conformal) format in accordance with the physician approved plan.
Indications for use as stated in the FDA summary.
https://510kreport.com/device/K121934 · printed Nov 6, 2026
Cite this page
510(k) Report. “K121934: Tomotherapy Treatment System.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 6, 2026. https://510kreport.com/device/K121934
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Record history
- FDA decision record loaded May 2, 2026
- Summary read Oct 13, 2026 (extraction version 9eaa42aa01ed)
- Lineage and recalls computed Nov 3, 2026
- Page last updated Nov 3, 2026