510(k) · Cleared
ClearedS250-FIT Proton Beam Radiation Therapy Device (S250-FIT)
Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly
Mevion Medical Systems, Inc. · LHN System, Radiation Therapy, Charged-Particle, Medical
Cleared on Sep 12, 2025 as substantially equivalent to K172848 (Mevion Medical Systems, 2017) after a 165-day review. Its family tree reaches back 8 generations to 1988. 1 later device descends from it.
- Decided
- Sep 12, 2025
- Review
- 165 days
- Class
- Class II
- Product code
- LHN
- Recalls
- None
- Predicates
- 1
Its longest line of descent runs back 8 generations to K872369 (1988). 16 ancestors in all. 1 later device descends from it, 1 citing it directly.
- Root · 8 generations backK872369 Loma Linda Univ. Proton Beam Therapy SystemLoma Linda University Medical Center · 1988
- 7 generations backK983024 Proton Therapy SystemIon Beam Applications S.A. · 2001
- 6 generations backK053641 Iba Proton Therapy System-Proteus 235Ion Beam Applications S.A. · 2006
- 5 generations backK060695 Iba Proton Therapy System - Proteus 235Ion Beam Applications S.A. · 2006 · Recalled
- 4 generations backK062891 Proton Therapy SystemIndiana University Cyclotron Facility · 2006
- 3 generations backK120676 S-250 Proton Beam Radiation Therapy SystemMevion Medical Systems · 2012 · Recalled
- 2 generations backK152224 Proton Therapy System - Proteus 235 (Proteus One, Proteus Plus…Ion Beam Application S.A. · 2016 · Recalled
- 1 generation backK172848 MEVION S250i Proton Beam Radiation Therapy DeviceMevion Medical Systems · 2017 · Recalled
- This deviceK250986 S250-FIT Proton Beam Radiation Therapy Device (S250-FIT)Mevion Medical Systems, Inc. · 2025
- Descendant · cites it directly · 0 of its ownK253406 S250-FIT Proton Beam Radiation Therapy Device (S250-FIT)Mevion Medical Systems, Inc. · 2026
Most influential descendants
Showing 1 of 1 · See all- K253406S250-FIT Proton Beam Radiation Therapy Device (S250-FIT)Mevion Medical Systems, Inc. · 2026 · cites it directly0descendants
View FIG. 1 as a table
Line of descent and top descendants
| Generation | Number | Device | Applicant | Decided | Recalls |
|---|---|---|---|---|---|
| −8 | K872369 | Loma Linda Univ. Proton Beam Therapy System | Loma Linda University Medical Center | 1988 | — |
| −7 | K983024 | Proton Therapy System | Ion Beam Applications S.A. | 2001 | — |
| −6 | K053641 | Iba Proton Therapy System-Proteus 235 | Ion Beam Applications S.A. | 2006 | — |
| −5 | K060695 | Iba Proton Therapy System - Proteus 235 | Ion Beam Applications S.A. | 2006 | 2 |
| −4 | K062891 | Proton Therapy System | Indiana University Cyclotron Facility | 2006 | — |
| −3 | K120676 | S-250 Proton Beam Radiation Therapy System | Mevion Medical Systems | 2012 | 12 |
| −2 | K152224 | Proton Therapy System - Proteus 235 (Proteus One, Proteus Plus, Proteus TK2) | Ion Beam Application S.A. | 2016 | 7 |
| −1 | K172848 | MEVION S250i Proton Beam Radiation Therapy Device | Mevion Medical Systems | 2017 | 5 |
| 0 (this device) | K250986 | S250-FIT Proton Beam Radiation Therapy Device (S250-FIT) | Mevion Medical Systems, Inc. | 2025 | — |
| +1 | K253406 | S250-FIT Proton Beam Radiation Therapy Device (S250-FIT) | Mevion Medical Systems, Inc. | 2026 | — |
Other ancestors by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 2000 | 1 | 0 |
| 2001 | 1 | 0 |
| 2006 | 2 | 0 |
| 2008 | 1 | 0 |
| 2010 | 2 | 0 |
| 2014 | 1 | 0 |
Descendants by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 2026 | 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 LHN? 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 LHN device
- #1 K260597 Virtue QAscore 15.4 · 12 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 |
|---|---|---|---|
| * | K172848 | MEVION S250i Proton Beam Radiation Therapy DeviceSummary page 5…-Particle, Medical Regulation Number: 892.5050 Product Code: LHN III. Predicate Device Predicate Device: MEVION S250i Proton Beam Radiation Therapy Device (K172848) Regulation Number: 892.5050 Product Code: LHN… | 2017 |
| † | K221996 | P-Cure Proton Beam Therapy System | 2023 |
What descends from it? (1)
1 later device cites it directly; ranked here by how many devices descend from each in turn.
| Number | Device | Decided | Descendants |
|---|---|---|---|
| K253406 | S250-FIT Proton Beam Radiation Therapy Device (S250-FIT) | 2026 | 0 |
Has anything in its family been recalled? (0 Class I)
No FDA recall names this device.
No ancestor or descendant has a Class I recall.
What does this lineage say?
- The line of descent spans 37 years and passes through 6 companies; a new generation was cleared every 4.5 years on median.
- 8 of the 16 ancestors have a recall of any class.
- Of its descendants, K253406 (Mevion Medical Systems, Inc., 2026) has gone furthest, with 0 descendants of its own.
How does its category compare?
All LHN devicesLHN System, Radiation Therapy, Charged-Particle, Medical: FDA decisions, review times, recalls and adverse event reports over 20 years. 2025, this device’s year, is highlighted.
FDA decisions per year · LHN
3in 2025
2026 to Oct 25, outlined.
Median 510(k) review, days · LHN
190in 2025
Receipt to decision; years with fewer than 3 clearances left blank.
Recalls per year · LHN
1in 2023
Class I (0 since 2007) Class II/III not classified
Adverse event reports per year · LHN
11in 2025
MAUDE reports naming product code LHN, 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 | 2 | — | 2 | 0 |
| 2008 | 3 | 113 | 2 | 1 |
| 2009 | 5 | 69 | 0 | 5 |
| 2010 | 4 | 96 | 0 | 3 |
| 2011 | 1 | — | 0 | 1 |
| 2012 | 3 | 111 | 0 | 1 |
| 2013 | 3 | 70 | 0 | 1 |
| 2014 | 4 | 93 | 2 | 5 |
| 2015 | 3 | 53 | 1 | 2 |
| 2016 | 7 | 120 | 0 | 1 |
| 2017 | 4 | 173 | 5 | 7 |
| 2018 | 3 | 78 | 2 | 8 |
| 2019 | 2 | — | 0 | 3 |
| 2020 | 4 | 74 | 1 | 20 |
| 2021 | 0 | — | 1 | 24 |
| 2022 | 2 | — | 2 | 10 |
| 2023 | 2 | — | 1 | 7 |
| 2024 | 1 | — | 0 | 2 |
| 2025 | 3 | 190 | 0 | 11 |
| 2026 | 4 | 194 | 0 | — |
What is it indicated for?
The MEVION S250-FIT Proton Beam Radiation Therapy Device is intended to deliver proton radiation treatment to patients with localized tumors or any other conditions susceptible to treatment by radiation. When the patient is in the fully seated position, the MEVION S250-FIT is indicated for treatment of patients with localized tumors and other conditions susceptible to treatment by radiation in the sites above the mid-chest or carina.
Indications for use as stated in the FDA summary.
https://510kreport.com/device/K250986 · printed Nov 5, 2026
Cite this page
510(k) Report. “K250986: S250-FIT Proton Beam Radiation Therapy Device (S250-FIT).” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 5, 2026. https://510kreport.com/device/K250986
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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