MAUDE Adverse Event Report: HITACHI,LTD. PROBEAT-FR; PROTON BEAM THERAPY SYSTEM

Medical Device Problem Code	Computer Software Problem (1112)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	12/05/2025
Type of Reportable Event	Malfunction
Event or Problem Description
During patient setup for proton therapy, after cbct imaging, the hmi displayed coordinates matched the planned values; however, a positional deviation of approximately 3 cm in the x-axis was confirmed using a laser marker.This discrepancy was resolved after re-performing the setup and verifying with pias 2d-2d matching mode.No patient injury occurred, and treatment proceeded normally after correction.A software anomaly in the patient positioning system (pps) may cause a mismatch between the commanded error correction parameter flag in the command data and the commanded error correction parameter flag in the command data of the couch controller, resulting in unintended positional deviation while the hmi continues to display the planned coordinates.The investigation suggests that the error-correction parameter may fail to be applied as intended at a rate of (b)(4) occurrences out of approximately (b)(4) operations (reproduction probability of about (b)(4)).In case where treatment begins without patient position verification after a software anomaly occurs in the pps, there is a risk of delivering radiation to non-target tissue, potentially causing serious injury.The incident was reported on december 5, 2025, and logs were reviewed immediately.No health injury has been reported.While the events observed do not currently present an unreasonable risk of substantial harm to public health, we determined that this is a 30-day reportable malfunction due to a potential risk that may arise when the operator does not follow the operating manual and skips the required x-ray-based patient position verification, which could allow a positioning mismatch to go undetected.At this time, no service bulletin has been issued and no user training has been conducted; these will be prepared as part of the corrective actions.In addition, we plan a software correction to detect any mismatch between the commanded error correction parameter flag in the command data and the commanded error correction parameter flag in the command data of the couch controller at motion start, output an error to the upper control, and prevent motion completion, and we intend to submit a correction/removal report under 21 cfr part 806 to prevent recurrence.
Additional Manufacturer Narrative
The event was initially known at the site, but issuance of our internal preliminary complaint report ("potential complaint") was delayed, so ra/qa became officially aware later.

• Brand Name: PROBEAT-FR
• Common Device Name: PROTON BEAM THERAPY SYSTEM
• Manufacturer (Section D): HITACHI,LTD.; 226-44-141-1, wakashiba; kashiwa-shi, chiba 277-0 871; JA 277-0871
• Manufacturer Contact: mikimoto takamatsu ; 226-44-141-1, wakashiba; kashiwa-shi, chiba 277-0-871 ; JA 277-0871
• MDR Report Key: 24121790
• Report Number: 1000162206-2026-00001
• Device Sequence Number: 5987842
• Product Code: LHN
• UDI-Device Identifier: 04560333350204
• UDI-Public: (01)04560333350204(11)240112
• Combination Product (Y/N): N
• Initial Reporter State: TX
• Initial Reporter Country: US
• PMA/510(K) Number: K232032
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Non-Healthcare Professional
• Type of Report: Initial
• Report Date (Section B): 01/20/2026

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Operator of Device: Health Professional
• Was Device Available for Evaluation?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 01/04/2026
• Initial Report FDA Received Date: 01/20/2026
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 01/12/2024
• Is the Device Labeled for Single Use? (Y/N): No
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Reuse
• Patient Sequence Number: 1
• Patient Sex: Unknown